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Sample records for cassini inca instrument

  1. A three-coordinate system (ecliptic, galactic, ISMF) spectral analysis of heliospheric ENA emissions using CASSINI/INCA measurements

    Energy Technology Data Exchange (ETDEWEB)

    Dialynas, K.; Krimigis, S. M. [Office for Space Research and Technology, Academy of Athens, 106 79 Athens (Greece); Mitchell, D. G.; Roelof, E. C.; Decker, R. B, E-mail: kdialynas@phys.uoa.gr [Applied Physics Laboratory, Johns Hopkins University, Laurel, MD (United States)

    2013-11-20

    In the present study, we use all-sky energy-resolved energetic neutral atom (ENA) maps obtained by the Ion and Neutral CAmera (INCA) instrument on board Cassini that correspond to the time period from 2003 to 2009, in four discrete energy passbands (∼5.4 to ∼55 keV), to investigate the geometrical characteristics of the belt (a broad band of emission in the sky). The heliospheric ENA emissions are mapped in three different coordinate systems (ecliptic, Galactic, and interstellar magnetic field (ISMF)), and spectral analyses are performed to further examine the belt's possible energy dependence. Our conclusions are summarized as follows: (1) the high flux ENA belt identified in the energy range of 8-42 keV is moderately well organized in Galactic coordinates, as the ENA minima appear in the vicinity of the north and south Galactic poles; (2) using minimization criteria ( B · R ∼ 0), the deviation of the ENA emissions from the equator is effectively minimized in a rotated frame, which we interpret as ISMF, where its north pole points toward 190° ecliptic longitude and 15° ecliptic latitude; (3) ENA spectra show a power-law form in energy that can be fitted with a single function presenting higher spectral slopes in the belt region and lower outside (3.4 < γ < 4.4); (4) the spectra are almost indistinguishable between the tail and the nose regions, i.e., no noticeable asymmetry is observed; (5) the consistency of the ENA distributions as a function of latitude among the different INCA channels indicates that the morphology of the belt (peak, width, and structure) is nearly energy independent from 8 keV to 30 keV (minor deviations start to appear at >35 keV); and (6) in the low count rate regions, the long-term ENA count rate profiles do not match the measured cosmic ray profiles, indicating that even the minimum ENA emissions detected by INCA are foreground ENAs.

  2. Heliosheath ENA images by Cassini/INCA and in-situ hot plasma ion measurements by Voyagers

    Science.gov (United States)

    Krimigis, Stamatios; Roelof, Edmond; Mitchell, Donald; Decker, Robert; Dialynas, Konstantinos

    2016-07-01

    The advent of Energetic Neutral Atom (ENA) imaging, (the result of charge-exchange with energetic ions), has revealed the global nature of the heliosheath (HS) at both high ( > 5 keV, Cassini from 10 AU) and low (INCA (Ion and Neutral CAmera) since 2003 with a full image available since 2009, when IBEX global imaging observations also became available. The presence of the two Voyagers measuring ions locally in the HS contemporaneously with INCA global imaging through ENA in overlapping energy bands provides a powerful tool for examining the spatial, temporal, and spectral evolution of the source hot plasma ions and the global variability of the neutral component. Some of the key findings from the Voyagers and INCA measurements are as follows: (a) The HS contains a hot plasma population that carries a substantial part (30-50%) of the total pressure at E > 5 keV, the rest residing below that range, resulting in a beta (particle/magnetic pressure) always > 1, typically > 10. (b) The width of the HS in the direction of V1 is ˜~ 30 AU, but is thought to be larger (40-70 AU) in the southern ecliptic where V2 currently travels. (c) The ENA intensities at E > 5 keV exhibit a correlation with the solar cycle (SC) over the period 2003 to 2014, with minimum intensities in the anti-nose direction observed ˜~ 1.5 yrs after solar minimum followed by a recovery thereafter, and (d) The in situ ion measurements at V2 within the HS also show a similar SC dependence. The totality of the observations, together with the near-contemporaneous variability in intensities of ions in situ in the HS and ENA in the inner heliosphere suggests that the source of such emissions at E > 5 keV must reside in the HS. These observations constrain the shape of the HS and suggest configurations that are at some variance with current models.

  3. On the source of the 5-55 keV Heliosphere ENAs measured with Cassini/INCA

    Science.gov (United States)

    Dialynas, Konstantinos; Roelof, Edmond; Mitchell, Donald; Krimigis, Stamatios; Decker, Robert

    2016-07-01

    The Low Energy Charged Particle (LECP) in situ measurements from V1 and V2 have revealed a reservoir of ions and electrons that constitute the heliosheath (HS) after crossing the termination shock (TS) 35deg north and 32deg south of the ecliptic plane at 94 and 84 astronomical units (1 AU= 1.5 x10 ^{8} km), respectively. The outer Heliosphere boundary, the Heliopause (HP), has now been determined in the direction of V1 to be at ˜122 AU. The in situ measurements by each Voyager were placed in a global context by remote sensing images using ENA obtained with the Ion and Neutral Camera (INCA) onboard Cassini orbiting Saturn. The ENA images have revealed a 5.2-55 keV hydrogen (H) ENA region (Belt) that loops through the celestial sphere and contributes to balancing the pressure of the interstellar magnetic field (ISMF). Here we address one of the remaining and most important questions: Where do the 5-55 keV ENAs that INCA measures come from? We analyzed INCA all-sky maps from 2003 to 2015 and compare the solar cycle (SC) variation of the ENAs in both the nose (upstream) and anti-nose (downstream) directions with the intensities of > 30 keV ions (source of ENA through charge exchange-CE with H) measured in-situ by V1 and V2, in overlapping energy bands ˜30-55 keV. ENA intensities decrease during the declining phase of SC23 by ˜x3 from 2003 to 2011 but recover through 2014 (SC24); similarly, V1 and V2 ion intensities also decrease and then recover through 2014. The similarity of time profiles of remotely sensed ENA and locally measured ions are consistent with (a) ENA originating in the HS, and (b) the global HS responding promptly (within ˜1-1.5 years) to outward-propagating solar wind changes throughout the SC. Further, recovery of the Belt during SC24 precedes asymmetrically from south to north in the general direction of the nose. This may be related to the non-symmetric evolution of solar coronal holes during SC recovery.

  4. Probing the Boundaries of the Heliosphere Using Observations of the Polar ENA Flux from IBEX and Cassini/INCA

    Science.gov (United States)

    Reisenfeld, D. B.; Janzen, P. H.; Bzowski, M.; Dialynas, K.; Funsten, H. O.; Fuselier, S. A.; Galli, A.; Kubiak, M. A.; McComas, D. J.; Schwadron, N.; Sokol, J. M.

    2016-12-01

    The IBEX Mission has been collecting ENAs from the outer heliosphere for nearly eight years, or three-quarters of a solar cycle. In that time, we have observed clear evidence of the imprint of the solar cycle in the time variation in the ENA flux. The most detailed of such studies has focused on the polar ENA flux observed by IBEX-Hi, as the IBEX spacecraft attitude allows for continuous coverage of the ENA flux incident from the ecliptic poles (Reisenfeld et al. 2012, 2016). By time correlating the ENA-derived heliosheath pressure to the observed 1 AU dynamic pressure, we can estimate the distance to the ENA source region. We can further derive the thickness of the ENA-producing region (presumably the inner heliosheath) by assuming pressure balance at the termination shock (TS). This requires using the 1 AU observations to derive the dynamic pressure at the TS shock by use of a mass-loaded solar wind propagation model (Schwadron et al. 2011), and by integrating ENA observations across all energies that significantly contribute to the heliosheath pressure. This means including polar ENA observations from not only IBEX-Hi, but from IBEX-Lo and Cassini/INCA, spanning an energy range of 15 eV to 40 keV. We will present our latest polar ENA observations and estimates for the distance to the TS and the thickness of the heliosheath.

  5. Energetic Neutral Atom (ENA) intensity gradients in the heliotail during year 2003, using Cassini/INCA measurements

    Science.gov (United States)

    Dialynas, K.; Krimigis, S. M.; Mitchell, D. G.; Roelof, E. C.

    2015-01-01

    In the present study we use all-sky energy-resolved (5-55 keV) energetic neutral atom (ENA) maps obtained by the Ion and Neutral CAmera (INCA) on board Cassini during the time period DOY 265/2003 to 268/2003, to investigate the properties of the peak-to-basin ENA emissions in the direction of the heliotail. Our conclusions can be summarized as follows: (1) a relatively smooth boundary (called "transition region") between the very low (basin) and high (tail) ENA emissions from the heliosheath, with a spatial width of ~30° deg in ecl. longitude, that no theory had predicted to date, is identified in the energy range of 5-55 keV; (2) the ENA intensity gradient in this transition region is almost invariant as a function of both ecl. Latitude and energy, with an average value of ~2.4% per degree; (3) the deduced partial plasma pressure distributions in the 5-55 keV energy range are consistent with the ENA intensity distributions in the same energy range, while the ENA intensity gradient translates to a corresponding partial pressure gradient that occurs in the transition region; and (4) this partial pressure gradient is possibly not consistent with a tail magnetic field configuration that is similar to the measured magnetic fields by the Voyagers in the nose hemisphere.

  6. Energetic Neutral Atom (ENA) Movies and Other Cool Data from Cassini's Magnetosphere Imaging Instrument (MIMI)

    Science.gov (United States)

    Kusterer, M. B.; Mitchell, D. G.; Krimigis, S. M.; Vandegriff, J. D.

    2014-12-01

    Having been at Saturn for over a decade, the MIMI instrument on Cassini has created a rich dataset containing many details about Saturn's magnetosphere. In particular, the images of energetic neutral atoms (ENAs) taken by the Ion and Neutral Camera (INCA) offer a global perspective on Saturn's plasma environment. The MIMI team is now regularly making movies (in MP4 format) consisting of consecutive ENA images. The movies correct for spacecraft attitude changes by projecting the images (whose viewing angles can substantially vary from one image to the next) into a fixed inertial frame that makes it easy to view spatial features evolving in time. These movies are now being delivered to the PDS and are also available at the MIMI team web site. Several other higher order products are now also available, including 20-day energy-time spectrograms for the Charge-Energy-Mass Spectrometer (CHEMS) sensor, and daily energy-time spectrograms for the Low Energy Magnetospheric Measurements system (LEMMS) sensor. All spectrograms are available as plots or digital data in ASCII format. For all MIMI sensors, a Data User Guide is also available. This paper presents details and examples covering the specifics of MIMI higher order data products. URL: http://cassini-mimi.jhuapl.edu/

  7. iPhone App for Cassini's Magnetospheric Imaging Instrument (MIMI) Browse Products

    Science.gov (United States)

    Myers, H. Y.; Kusterer, M. B.; Mitchell, D. G.; Steele, R. J.; Vandegriff, J. D.

    2016-12-01

    We have created a mobile app on the iOS platform to view the years of browse plots from data collected by the MIMI instruments on Cassini. The focus of the app is to bring the browsing capabilities of the MIMI database to the touchscreen technologies that exist on mobile devices such as smartphones and tablets. Among the data products within the MIMI suite that are viewable through the app include the Energetic Neutral Atom (ENA) images and movies of Saturn taken with the Ion and Neutral Camera (INCA), and spectrograms and line plots from the LEMMS and CHEMS particle detectors. The release of this app also coincides with access to a number of MIMI data products previously not available to the public. We will unveil the features of the app and provide a working demo. The CassiniMIMI app will be available for free from Apple's iTunes Store. A sneak preview of some selection screens and a representative plot are shown in the separate image file.

  8. Response times of Cassini/INCA > 5.2 keV ENAs and Voyager ions in the heliosheath over the solar cycle

    Science.gov (United States)

    Dialynas, K.; Krimigis, S. M.; Mitchell, D. G.; Decker, R. B.; Roelof, E. C.

    2017-09-01

    Both a magnetosphere-like tail and a bubble model of the heliosphere were posited by E. N. Parker in 1961. Recently, we showed that heliosheath ions are the source of > 5.2 keV Energetic Neutral Atoms (ENA), whose images of the heliosphere exhibit a rough nose to anti-nose (tail) global symmetry that resembles a diamagnetic bubble. The comparison between energetic neutral atom (ENA) global images of the helioshphere obtained with the Ion and Neutral Camera (INCA) on board Cassini and ions measured in-situ by the Low Energy Charged Particle experiment (LECP) on board Voyager 1 and 2 (V1/V2) in overlapping energy bands over an 11-year period shows that the heliosphere responds promptly, within ∼2-3 years, to outward propagating solar wind changes in both the nose and tail directions. Here we focus on the recovery of solar cycle 24 and the response times of > 5.2 keV ENAs to show that this ∼2-3-year time delay is consistent with a “tail” of ∼80-120 AU. This preliminary rough calculation is generally consistent with lower energy ENA data (E < 6 keV, from the IBEX-Lo and IBEX-Hi) and is supported by recent modelling of the heliosphere.

  9. On the shape and properties of the global heliosphere over the Solar Cycle with Voyager/LECP ions and Cassini/INCA ENAs

    Science.gov (United States)

    Dialynas, Konstantinos; Krimigis, Stamatios; Mitchell, Donald; Decker, Robert; Roelof, Edmond

    2017-04-01

    Voyager 1 (V1) and Voyager 2 (V2) have crossed the termination shock in 2004 (V1) and 2007(V2) and traversing the Heliosheath (HS) in the upstream (nose) hemisphere, while the Ion and Neutral Camera (INCA) on Cassini enables Energetic Neutral Atom (ENA) images of the celestial sphere that place the local ion measurements by each Voyager in a global context. We present an analysis of 5.2-55 keV ENA global images of the HS and 28-53 keV in-situ ions over an 11-year period (2003-2014) that corresponds to the declining phase of solar cycle 23 (SC23) and onset of SC24. The measurements reveal a coherent decrease and recovery between ENA in the global heliosphere and in-situ ions at V1/V2 during this time period, in overlapping energy bands, establishing that the HS ions are the source of >28 keV ENA. The similarity in the overall appearance of the images throughout the INCA energy range (5.2-55 keV), reveals that the source of ENAs at 5.2 keV ENA and ion variations with the Solar Sunspot Numbers (SSN) and solar wind parameters indicates that the Heliosphere responds promptly, within 2-3 years, to outward propagating solar wind changes in both the nose and anti-nose (tail) directions following the Solar Cycle (SC) phases. A detailed latitudinal examination of the global ENA emissions, verifies that the peak intensities between the nose and anti-nose directions are nearly similar, the power law ENA spectral index (γ) is largely the same near the equator in both the nose and anti-nose directions and displays similar spatial dependence with latitude. The totality of the ENA and in situ ion observations, together with the V1 measurement of a 0.5 nT interstellar magnetic field (ISMF) and recent modeling, suggest a "bubble-shape" heliosphere, i.e with little substantial tail-like feature. These observations are essential in determining the context for the measurements anticipated by the forthcoming IMAP mission.

  10. Coherent dust cloud observed by three Cassini instruments

    CERN Document Server

    Khalisi, Emil

    2015-01-01

    We revisit the evidence for a "dust cloud" observed by the Cassini spacecraft at Saturn in 2006. The simultaneous data of 3 instruments are compared to interpret the signatures of a coherent swarm of dust that could have remained floating near the equatorial plane. The conspicuous pattern, as seen in the dust counters of the Cosmic Dust Analyser (CDA) and in the magnetic field (MAG), clearly repeats on three consecutive revolutions of the spacecraft. The data of the Radio Plasma and Wave Science (RPWS) appear less decisive but do back our conclusions. The results support the idea of a "magnetic bubble" as reported from both Voyager flybys in the early 1980ies. That particular cloud, which we firstly discovered in the CDA data, is estimated to about 1.36 Saturnian radii in size, and probably broadening. Both the bulk of dust particles and the peak of the magnetic depression seem to drift apart, but this can also be an effect of hitting the cloud at different parts during the traverse.

  11. Inca Calendar

    Science.gov (United States)

    Ziółkowski, Mariusz

    The ritual, central Inca calendar, adapted to the ecological, cultural, and ethnic realities of the Cuzco valley, was the basis of the imperial calendar, used for the administration of the Inca Empire. According to the main historical sources, it was composed of 12 synodic months calculated from new moon to new moon. The correlation of this cycle with the tropical year was achieved by the intercalation of an additional 13th month, every 2 or 3 years. Tom Zuidema's thesis about the existence of the "stellar lunar calendar" or "quipu-calendar" is also analyzed.

  12. New multivariable capabilities of the INCA program

    Science.gov (United States)

    Bauer, Frank H.; Downing, John P.; Thorpe, Christopher J.

    1989-01-01

    The INteractive Controls Analysis (INCA) program was developed at NASA's Goddard Space Flight Center to provide a user friendly, efficient environment for the design and analysis of control systems, specifically spacecraft control systems. Since its inception, INCA has found extensive use in the design, development, and analysis of control systems for spacecraft, instruments, robotics, and pointing systems. The (INCA) program was initially developed as a comprehensive classical design analysis tool for small and large order control systems. The latest version of INCA, expected to be released in February of 1990, was expanded to include the capability to perform multivariable controls analysis and design.

  13. The Context for IMAP: Voyager and INCA Observations of the Heliosheath at E > 5 keV

    Science.gov (United States)

    Krimigis, Stamatios M.

    2016-04-01

    The basic premise of the proposed Interstellar Mapping and Acceleration Probe (IMAP) is detailed scientific understanding of the Heliosheath (HS) and beyond, a region of space explored in situ by Voyager 1 (V1) since 2004, Voyager 2 (V2) since 2007, and remotely via energetic neutral atoms (ENA) by the Cassini/INCA (Ion and Neutral CAmera) since 2003 and IBEX since 2009. The IMAP instrumentation proposed for this purpose combines and extends the IBEX and INCA ENA energy ranges (0.3- 20 keV and 3-200 keV, for low and high energy, respectively). All three missions-Voyagers, Cassini/INCA, and IBEX- have made discovery-class measurements in the HS, the Voyagers providing in situ ion intensities at E > 30 keV, while INCA images ENA in the range 5 INCA ENA allows for the possibility of observing the intensity and time evolution of ions in the HS, thought to give rise to the ENAs via charge-exchange, and the resultant ENA images in the inner heliosphere and their spatial and/or temporal variability. Unfortunately, no such "ground truth" ion measurements are possible at Voyager in the ENA energy range imaged by IBEX. Some of the key findings from the Voyager and Cassini/INCA measurements are as follows: (1) The HS contains a hot plasma population that carries a substantial part (30-50 %) of the total pressure at E > 5 keV, the rest residing below that range, resulting in a beta (particle/magnetic pressure) always > 1, typically >10. (2) The width of the HS in the direction of V1 is ~ 30 AU, but is thought to be larger (40-70 AU) in the southern ecliptic where V2 currently travels.. (3) The ENA intensities at E > 5 keV exhibit a correlation with the solar cycle (SC) over the period 2003 to 2015, with minimum intensities in the anti-nose direction observed ~ 1.5 yrs after solar minimum followed by a recovery thereafter. (4) The in situ ion measurements at V2 within the HS also show a similar SC dependence. The totality of the observations, together with the near

  14. Interactive Controls Analysis (INCA)

    Science.gov (United States)

    Bauer, Frank H.

    1989-01-01

    Version 3.12 of INCA provides user-friendly environment for design and analysis of linear control systems. System configuration and parameters easily adjusted, enabling INCA user to create compensation networks and perform sensitivity analysis in convenient manner. Full complement of graphical routines makes output easy to understand. Written in Pascal and FORTRAN.

  15. Interactive Controls Analysis (INCA)

    Science.gov (United States)

    Bauer, Frank H.

    1989-01-01

    Version 3.12 of INCA provides user-friendly environment for design and analysis of linear control systems. System configuration and parameters easily adjusted, enabling INCA user to create compensation networks and perform sensitivity analysis in convenient manner. Full complement of graphical routines makes output easy to understand. Written in Pascal and FORTRAN.

  16. Inca Astronomy and Calendrics

    Science.gov (United States)

    Dearborn, David S. P.; Bauer, Brian S.

    Half a millennium ago in the central Andes of Peru, the movements of the sun, moon, and stars were watched and interpreted by the Inca. The astronomical observations made in and near the former capital, Cuzco, formed the nuclei of the most important public rituals of the empire. As the regulator of time, the ruling Inca scheduled the rituals that bound this society together. In this article, we review the major astronomical observations that were made by the Inca and discuss their importance in defining the ritual calendar.

  17. Exploration of the Saturn System by the Cassini Mission: Observations with the Cassini Infrared Spectrometer

    Science.gov (United States)

    Abbas, Mian M.

    2014-01-01

    Outline: Introduction to the Cassini mission, and Cassini mission Objectives; Cassini spacecraft, instruments, launch, and orbit insertion; Saturn, Rings, and Satellite, Titan; Composite Infrared Spectrometer (CIRS); and Infrared observations of Saturn and titan.

  18. INCA- INTERACTIVE CONTROLS ANALYSIS

    Science.gov (United States)

    Bauer, F. H.

    1994-01-01

    The Interactive Controls Analysis (INCA) program was developed to provide a user friendly environment for the design and analysis of linear control systems, primarily feedback control systems. INCA is designed for use with both small and large order systems. Using the interactive graphics capability, the INCA user can quickly plot a root locus, frequency response, or time response of either a continuous time system or a sampled data system. The system configuration and parameters can be easily changed, allowing the INCA user to design compensation networks and perform sensitivity analysis in a very convenient manner. A journal file capability is included. This stores an entire sequence of commands, generated during an INCA session into a file which can be accessed later. Also included in INCA are a context-sensitive help library, a screen editor, and plot windows. INCA is robust to VAX-specific overflow problems. The transfer function is the basic unit of INCA. Transfer functions are automatically saved and are available to the INCA user at any time. A powerful, user friendly transfer function manipulation and editing capability is built into the INCA program. The user can do all transfer function manipulations and plotting without leaving INCA, although provisions are made to input transfer functions from data files. By using a small set of commands, the user may compute and edit transfer functions, and then examine these functions by using the ROOT_LOCUS, FREQUENCY_RESPONSE, and TIME_RESPONSE capabilities. Basic input data, including gains, are handled as single-input single-output transfer functions. These functions can be developed using the function editor or by using FORTRAN- like arithmetic expressions. In addition to the arithmetic functions, special functions are available to 1) compute step, ramp, and sinusoid functions, 2) compute closed loop transfer functions, 3) convert from S plane to Z plane with optional advanced Z transform, and 4) convert from Z

  19. INCA- INTERACTIVE CONTROLS ANALYSIS

    Science.gov (United States)

    Bauer, F. H.

    1994-01-01

    The Interactive Controls Analysis (INCA) program was developed to provide a user friendly environment for the design and analysis of linear control systems, primarily feedback control systems. INCA is designed for use with both small and large order systems. Using the interactive graphics capability, the INCA user can quickly plot a root locus, frequency response, or time response of either a continuous time system or a sampled data system. The system configuration and parameters can be easily changed, allowing the INCA user to design compensation networks and perform sensitivity analysis in a very convenient manner. A journal file capability is included. This stores an entire sequence of commands, generated during an INCA session into a file which can be accessed later. Also included in INCA are a context-sensitive help library, a screen editor, and plot windows. INCA is robust to VAX-specific overflow problems. The transfer function is the basic unit of INCA. Transfer functions are automatically saved and are available to the INCA user at any time. A powerful, user friendly transfer function manipulation and editing capability is built into the INCA program. The user can do all transfer function manipulations and plotting without leaving INCA, although provisions are made to input transfer functions from data files. By using a small set of commands, the user may compute and edit transfer functions, and then examine these functions by using the ROOT_LOCUS, FREQUENCY_RESPONSE, and TIME_RESPONSE capabilities. Basic input data, including gains, are handled as single-input single-output transfer functions. These functions can be developed using the function editor or by using FORTRAN- like arithmetic expressions. In addition to the arithmetic functions, special functions are available to 1) compute step, ramp, and sinusoid functions, 2) compute closed loop transfer functions, 3) convert from S plane to Z plane with optional advanced Z transform, and 4) convert from Z

  20. Solar Cycle dependence of 5-55 keV Cassini/INCA energetic neutral atom (ENA) images of the Heliosheath and in situ Voyager/LECP ion measurements

    Science.gov (United States)

    Krimigis, S. M.; Dialynas, K.; Mitchell, D. G.; Decker, R. B.; Roelof, E. C.

    2015-12-01

    The heliosheath has been identified as the most probable source of ENAs that INCA detects but its variability due to solar activity throughout the solar cycle (SC) has not been resolved to date. We show all-sky, 5-55 keV ENA H maps from the year 2003 to 2014 and compare the solar cycle variation of the ENAs in both the heliospheric nose (upstream) and anti-nose (downstream) directions with the > 30 keV ions measured within the heliosheath by the Low Energy Charged Particle (LECP) detector on Voyagers 1, 2 (V1, V2) where we measure protons in overlapping energy bands ~30-55 keV. We find that a) Toward the anti-nose direction the ENA-H intensities decline during SC23, i.e. after 2003 ENA intensities decreased by ~ x2 at all energies by the end of year 2011, ~1 year after the observed minimum in solar activity; b) This ENA decrease (5.2-55 keV) during 2009-2011 is consistent with the concurrent intensity decrease of the > 30 keV ions (by a factor of 2-3) observed in situ by V1 and V2 in the heliosheath; c) Toward the nose direction, minimum intensities in both INCA ENAs and the V2 ions at E > 28 keV occur during the year 2013, with a subsequent recovery from 2014 to date (by a factor of ~2 in the > 35 keV ENA data). These quantitative correlations between the decreases of INCA ENAs (in both the heliospheric nose and anti-nose directions) and the in situ V1 and V2 ion measurements (separated by > 130 AU) during the declining phase of SC23, along with their concurrent jointly shared recoveries at the onset of SC24, imply that: 1) the 5-55 keV ENAs are produced in the heliosheath (because their transit times over 100 AU are less than a few months at energies > 40 keV), thus proving that our ENA observations can provide the ground truth for constructing comprehensive global heliosphere models; 2) the global heliosheath responds promptly (within ~1-1.5 yrs) to outward-propagating solar wind changes throughout the solar cycle.

  1. Inca Digital推出Inca Onset

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Inca数码印刷公司推出了Inca Onset平台型UV喷墨数字印刷机,此举在大幅面UV喷墨数字印刷领域具有突破性意义。该设备具有惊人的输出能力.100张全开幅面每小时.打印尺寸可达3.2×1.5米.速度可达每小时500平方米。

  2. Cassini/MIMI Measurements in Saturn's Magnetosphere and their Implications for Magnetospheric Dynamics

    Science.gov (United States)

    Mitchell, D. G.

    2016-12-01

    The Cassini spacecraft has been in orbit about Saturn since early July, 2004. In less than a year, on September 15, 2017, Cassini will plunge into Saturn's atmosphere, ending what has been a highly successful and interesting mission. As befitting a Planetary Division Flagship Mission, Cassini's science payload included instrumentation designed for a multitude of science objectives, from surfaces of moons to rings to atmospheres to Saturn's vast, fast-rotating magnetosphere. Saturn's magnetosphere exhibits considerable variability, both from inner magnetosphere to outer, and over time. Characterizing the dynamics of the magnetosphere has required the full range of energetic particles (measured by the magnetospheric imaging instrument, MIMI - https://saturn.jpl.nasa.gov/magnetospheric-imaging-instrument/), plasma (provided by the Cassini plasma spectrometer, CAPS), gas (ion and neutral mass spectrometer, INMS), magnetic fields (Cassini magnetometer, MAG), radio and plasma waves (radio and plasma wave science, RPWS), dust (Cassini Dust Analyzer, CDA), as well as ultraviolet, visible and infrared imaging (ultraviolet imaging spectrograph, UVIS; Cassini imaging subsystem ISS; visible and infrared mapping spectrometer, VIMS; Cassini composite infrared spectrometer, CIRS) and ionospheric sounding by the Cassini radio science subsystem (RSS). It has also required the full range of orbital geometries from equatorial to high inclination and all local times, as well as the full range of solar wind conditions, seasonal sun-Saturn configurations. In this talk we focus on the contributions of the MIMI instrument suite (CHEMS, LEMMS, and INCA) to our understanding of the dynamics of Saturn's magnetosphere. We will both review past work, and present recent observations from the high inclination orbits that precede the final stages of the Cassini mission, the sets of high inclination orbits that cross the equator just beyond the edge of the main ring system, and later cross between

  3. Cassini ENA Observations of an Asymmetric Europa Torus and Implications for JUICE

    Science.gov (United States)

    Brandt, Pontus; Westlake, Joseph H.; Smith, Howard T.; mauk, Barry; Mitchell, Don

    2016-10-01

    From about December 2000 to January 2001 the Ion Neutral Camera (INCA) on board the Cassini spacecraft imaged Jupiter in Energetic Neutral Atoms (ENA) that are created when singly charged ions charge exchange with neutral gas atoms or molecules. The INCA observations were obtained from a distance of about 137-250 Jovian planetary radii (RJ) over an energy range from about 10 to 300 keV. Here, we present an analysis of the ENA images implying an asymmetric Europa neutral gas torus with indications of magnetospheric dynamics. The analysis uses images with a minimum integration time and background. A forward model using a parametric energetic ion model and a neutral gas model simulates ENA images through the instrument response function of INCA in order to determine the spatial distribution of the neutral gas. Implications for the ENA observations from the ESA JUICE Mission obtained by the Jovian Energetic Neutrals and Ions (JENI) Camera on the Particle Environment Package (PEP) suite will be discussed.

  4. Control system design and analysis using the INteractive Controls Analysis (INCA) program

    Science.gov (United States)

    Bauer, Frank H.; Downing, John P.

    1987-01-01

    The INteractive Controls Analysis (INCA) program was developed at the Goddard Space Flight Center to provide a user friendly efficient environment for the design and analysis of linear control systems. Since its inception, INCA has found extensive use in the design, development, and analysis of control systems for spacecraft, instruments, robotics, and pointing systems. Moreover, the results of the analytic tools imbedded in INCA have been flight proven with at least three currently orbiting spacecraft. This paper describes the INCA program and illustrates, using a flight proven example, how the package can perform complex design analyses with relative ease.

  5. Control system design and analysis using the INteractive Controls Analysis (INCA) program

    Science.gov (United States)

    Bauer, Frank H.; Downing, John P.

    1987-01-01

    The INteractive Controls Analysis (INCA) program was developed at the Goddard Space Flight Center to provide a user friendly efficient environment for the design and analysis of linear control systems. Since its inception, INCA has found extensive use in the design, development, and analysis of control systems for spacecraft, instruments, robotics, and pointing systems. Moreover, the results of the analytic tools imbedded in INCA have been flight proven with at least three currently orbiting spacecraft. This paper describes the INCA program and illustrates, using a flight proven example, how the package can perform complex design analyses with relative ease.

  6. Camino Inca Cajamarca – Baños del Inca

    OpenAIRE

    Camargo Mareovich, Cecilia; León Ascurra, Wilder Javier

    2014-01-01

    En 1532 los capitanes Hernando de Soto y Hernando Pizarro recorrieron un antiguo camino desde la actual Plaza de Armas de Cajamarca hasta los Baños del Inca para entrevistarse con el Inca Atahualpa, quien recorrió por última vez este camino para su encuentro con Francisco Pizarro y sus huestes un 16 de noviembre de 1532. Esta información fue tomada de las descripciones del asentamiento inca que hicieran Hernando Pizarro (1537), Francisco de Xerez (1534), Miguel de Estete (1534), entre otros, ...

  7. Inca bones at asterion

    Directory of Open Access Journals (Sweden)

    Prashant E Natekar

    2014-01-01

    Full Text Available Background: Surgical approach towards asterion has to be done with caution as many surgeons are unfamiliar with the anatomical variations. The asterion corresponds to the site of the posterolateral (mastoid fontanelle of the neonatal skull which closes at the end of the first year. Inca bones provide information as markers for various diseases, and can mislead in the diagnosis of fractures. Observation and Results: 150 dry skull bones from the Department of Anatomy at Goa Medical College, India and other neighboring medical colleges by examining the asterion, and its sutural articulations with parietal, temporal and occipital bones and also anatomical variations if any in adults. Discussion: The anatomical landmarks selected must be reliable and above all easy to identify. Bony structures are more suitable than soft tissue or cartilaginous landmarks because of their rigid and reliable location. Presence of these bones provides false impressions of fractures or the fractures may be interpreted for inca bones especially in the region of asterion either radiologically or clinically which may lead to complications during burr hole surgeries.

  8. INCAS TRISONIC WIND TUNNEL

    Directory of Open Access Journals (Sweden)

    Florin MUNTEANU

    2009-09-01

    Full Text Available The 1.2 m x 1.2 m Trisonic Blowdown Wind Tunnel is the largest of the experimental facilities at the National Institute for Aerospace Research - I.N.C.A.S. "Elie Carafoli", Bucharest, Romania. The tunnel has been designed by the Canadian company DSMA (now AIOLOS and since its commissioning in 1978 has performed high speed aerodynamic tests for more than 120 projects of aircraft, missiles and other objects among which the twin jet fighter IAR-93, the jet trainer IAR-99, the MIG-21 Lancer, the Polish jet fighter YRYDA and others. In the last years the wind tunnel has been used mostly for experimental research in European projects such as UFAST. The high flow quality parameters and the wide range of testing capabilities ensure the competitivity of the tunnel at an international level.

  9. INCAS SUBSONIC WIND TUNNEL

    Directory of Open Access Journals (Sweden)

    Corneliu STOICA

    2009-09-01

    Full Text Available The INCAS Subsonic Wind Tunnel is a closed circuit, continuous, atmospheric pressure facility with a maximum speed of 110 m/s. The test section is octagonal ,of 2.5 m wide, 2.0 m high and 4 m long. The tunnel is powered by a 1200 kW, air cooled variable speed DC motor which drives a 12 blade, 3.5 m diameter fan and is equipped with a six component pyramidal type external mechanical balance with a 700 Kgf maximum lift capacity.The angle of attack range is between -45º and +45º while the yaw angle range is between -140º and +216º .The data acquisition system has been modified recently to allow the recording of all test data on a PC - type computer using LABVIEW and a PXI – type chassis containing specialized data acquisition modules.The tunnel is equipped with a variable frequency electrical supply system for powered models and a 10 bar compressed air supply for pneumatic flow control applications.In the recent years the subsonic wind tunnel has been intensively used for tests within several European projects (AVERT, CESAR and others.

  10. Ten Years of ENA Imaging from Cassini

    Science.gov (United States)

    Brandt, Pontus; Mitchell, Donald; Westlake, Joseph; Carbary, James; Paranicas, Christopher; Mauk, Barry; Krimigis, Stamatios

    2014-05-01

    In this presentation we will provide a detailed review of the science highlights of the ENA observations obtained by The Ion Neutral Camera (INCA) on board Cassini. Since the launch of Cassini, INCA has unveiled an invisible world of hot plasma and neutral gas of the two biggest objects of our solar system: the giant magnetosphere of Jupiter and Saturn. Although more than ten years ago, INCA captured the first ENA images of the Jovian system revealing magnetospheric dynamics and an asymmetric Europa neutral gas torus. Approaching Saturn, INCA observed variability of Saturn's magnetospheric activity in response to changes in solar wind dynamic pressure, which was contrary to expectations and current theories. In orbit around Saturn, INCA continued the surprises including the first imaging and global characterization of Titan's exosphere extended out to its gravitational Hill sphere; recurring injections correlating with periodic Saturn Kilometric Radiation (SKR) bursts and magnetic field perturbations; and the discovery of energetic ionospheric outflow. Perhaps most significant, and the focal point of this presentation, is INCA's contribution to the understanding of global magnetospheric particle acceleration and transport, where the combination between ENA imaging and in-situ measurements have demonstrated that transport and acceleration of plasma is likely to occur in a two-step process. First, large-scale injections in the post-midnight sector accelerate and transport plasma in to about 12 RS up to energies of several hundreds of keV. Second, centrifugal interchange acts on the plasma inside of this region and provides further heating and transport in to about 6RS. We discuss this finding in the context of the two fundamental types of injections (or ENA intensifications) that INCA has revealed during its ten years of imaging. The first type is large-scale injections appearing beyond 12 RS in the post-midnight sector that have in many cases had an inward component

  11. Protocol and data INCA trial

    NARCIS (Netherlands)

    Pelser, L.M.; Frankena, K.; Toorman, J.; Savelkoul, H.F.J.; Dubios, R.; Rodrigues Pereira, R.; Haagen, T.A.; Rommelse, N.N.; Buitelaar, J.K.

    2009-01-01

    The file INCAdata.csv contains the data collected during the INCA study (100 records with 152 variables). The data have been analysed and outcomes were published by Pelsser et al (2011): "Effects of a restricted elimination diet on the behaviour of children with attention-deficit hyperactivity

  12. Protocol and data INCA trial

    NARCIS (Netherlands)

    Pelser, L.M.; Frankena, K.; Toorman, J.; Savelkoul, H.F.J.; Dubios, R.; Rodrigues Pereira, R.; Haagen, T.A.; Rommelse, N.N.; Buitelaar, J.K.

    2009-01-01

    The file INCAdata.csv contains the data collected during the INCA study (100 records with 152 variables). The data have been analysed and outcomes were published by Pelsser et al (2011): "Effects of a restricted elimination diet on the behaviour of children with attention-deficit hyperactivity disor

  13. Protocol and data INCA trial

    NARCIS (Netherlands)

    Pelser, L.M.; Frankena, K.; Toorman, J.; Savelkoul, H.F.J.; Dubios, R.; Rodrigues Pereira, R.; Haagen, T.A.; Rommelse, N.N.; Buitelaar, J.K.

    2009-01-01

    The file INCAdata.csv contains the data collected during the INCA study (100 records with 152 variables). The data have been analysed and outcomes were published by Pelsser et al (2011): "Effects of a restricted elimination diet on the behaviour of children with attention-deficit hyperactivity disor

  14. Cassini science planning process

    Science.gov (United States)

    Paczkowski, Brian G.; Ray, Trina L.

    2004-01-01

    The mission design for Cassini-Huygens calls for a four-year orbital survey of the Saturnian system and the descent into the Titan atmosphere and eventual soft-landing of the Huygens probe. The Cassini orbiter tour consists of 76 orbits around Saturn with 44 close Titan flybys and 8 targeted icy satellite flybys. The Cassini orbiter spacecraft carries twelve scientific instruments that will perform a wide range of observations on a multitude of designated targets. The science opportunities, frequency of encounters, the length of the Tour, and the use of distributed operations pose significant challenges for developing the science plan for the orbiter mission. The Cassini Science Planning Process is the process used to develop and integrate the science and engineering plan that incorporates an acceptable level of science required to meet the primary mission objectives far the orbiter. The bulk of the integrated science and engineering plan will be developed prior to Saturn Orbit Insertion (Sol). The Science Planning Process consists of three elements: 1) the creation of the Tour Atlas, which identifies the science opportunities in the tour, 2) the development of the Science Operations Plan (SOP), which is the conflict-free timeline of all science observations and engineering activities, a constraint-checked spacecraft pointing profile, and data volume allocations to the science instruments, and 3) an Aftermarket and SOP Update process, which is used to update the SOP while in tour with the latest information on spacecraft performance, science opportunities, and ephemerides. This paper will discuss the various elements of the Science Planning Process used on the Cassini Mission to integrate, implement, and adapt the science and engineering activity plans for Tour.

  15. Interparietal (Inca bone: a case report

    Directory of Open Access Journals (Sweden)

    Udupi S

    2011-05-01

    Full Text Available The squamous part of occipital bone consists of two parts, supraoccipital and interparietal. The interparietal portion ossifies intramembranously and in rare cases may be separated from the supraoccipital part by a suture. It is then called as the interparietal or Inca bone. The occurrence of Inca variable is rare in humans. The authors here report a case of true interparietal or Inca bone in adult human skull. Knowledge of Inca ossicles in human skulls may be useful to neurosurgeons orthopedic surgeons, anthropologists, radiologists and forensic experts.

  16. The modern conception of the INCA project

    Energy Technology Data Exchange (ETDEWEB)

    Aleksandrov, K.V.; Ammosov, V.V.; Chechin, V.A.; Chubenko, A.P.; Erlykin, A.D.; Ladygin, E.A.; Merzon, G.I.; Mukhamedshin, R.A.; Murashev, V.N.; Pavlyuchenko, V.P.; Ryabov, V.A.; Ryazhskaya, O.G.; Saito, T.; Sobolevskii, N.M.; Shchepetov, A.L.; Starkov, N.I.; Trostin, I.S.; Tsarev, V.A.; Zatsepin, G.T.; Zhdanov, G.B.; Zhukov, A.P

    2003-07-01

    The goals and status of the INCA Project are presented. New technique based on the ionization-neutron calorimeter (INCA) and designed to study the energy spectrum and composition of the primary cosmic radiation in the 'knee' region as well as the spectrum of primary electrons in the range 0.1-10 TeV is discussed.

  17. OPUS: A Comprehensive Search Tool for Remote Sensing Observations of the Outer Planets. Now with Enhanced Geometric Metadata for Cassini and New Horizons Optical Remote Sensing Instruments.

    Science.gov (United States)

    Gordon, M. K.; Showalter, M. R.; Ballard, L.; Tiscareno, M.; French, R. S.; Olson, D.

    2017-06-01

    The PDS RMS Node hosts OPUS - an accurate, comprehensive search tool for spacecraft remote sensing observations. OPUS supports Cassini: CIRS, ISS, UVIS, VIMS; New Horizons: LORRI, MVIC; Galileo SSI; Voyager ISS; and Hubble: ACS, STIS, WFC3, WFPC2.

  18. The INCA project: present status and outlook

    Energy Technology Data Exchange (ETDEWEB)

    Aleksandrov, K.V.; Ammosov, V.V.; Chechin, V.A.; Chubenko, A.P.; Erlykin, A.D.; Ladygin, E.A.; Merzon, G.I.; Mukhamedshin, R.A.; Murashov, V.N.; Pavlyuchenko, V.P.; Ryabov, V.A.; Ryazhskaya, O.G.; Saito, T.; Sobolevskii, N.M.; Shchepetov, A.L.; Starkov, N.I.; Trostin, I.S.; Tsarev, V.A.; Wolfendale, A.; Zatsepin, G.T.; Zhdanov, G.B.; Zhukov, A.P

    2002-12-01

    Scientific objectives, foundations, status, and outlook of the INCA Project are presented. Fundamentally new technique based on the ionization-neutron calorimeter (INCA) and designed to study local nearby sources of high-energy cosmic rays by direct measuring the spectrum and composition of the nuclear component in the 'knee' region and the spectrum of primary electrons in the energy range 0.1-10 TeV with the proton-background suppression factor up to 10{sup 7} is discussed. Experimental data on exposition of the INCA prototypes to electron, pion, and proton beams at various energies and corresponding simulation results are presented. Prospects are considered.

  19. La imagen del Inca como benefactor

    Directory of Open Access Journals (Sweden)

    Juan Miguel Espinoza Portocarrero

    2010-07-01

    Full Text Available A partir de tres crónicas coloniales y de tres visiones historiográficas sobre los incas producidas en el siglo XX, y apelando a las herramientas metodológicas de la historia de las categorías, se pretende rastrear los discursos sobre la imagen del Inca como benefactor de la sociedad andina. El objetivo es dar luces sobre los discursos históricos que entienden al Inca como un modelo ideal de autoridad política y su carácter de construcción social afianzada por la historiografía.

  20. Identidad y ética en los Comentarios reales de los incas del Inca Garcilaso de la Vega

    DEFF Research Database (Denmark)

    Jensen, Hans Julio Casado

    2003-01-01

    Inca Garcilaso de la Vega. Historiografi. Renæssance. Spaniens erobring af Amerika. Etik. Paul Ricoeur......Inca Garcilaso de la Vega. Historiografi. Renæssance. Spaniens erobring af Amerika. Etik. Paul Ricoeur...

  1. Fatal Ichthyocotylurus erraticus infestation in Inca terns (Larosterna inca) in a zoological collection.

    Science.gov (United States)

    Pieters, Wouter; Hoyer, Mark; Verstappen, Frank; Wolters, Marno; Ijzer, Jooske; de Jong, Sara; Cremers, Herman; Kik, Marja

    2014-06-01

    In a breeding group of Inca terns (Larosterna inca), 14 birds died without antemortem signs of illness. Other than a poor body condition and a bloody cloaca, no symptoms were observed. Gross necropsy revealed severe segmental hemorrhagic enteritis with intralesional trematodes in most birds. Histopathologic examination revealed infiltration of lymphocytes, plasma cells, and granulocytes in the lamina propria of the duodenum and cross-sections of trematodes in the lumen. The parasites were identified as Ichthyocotylurus erraticus, a trematode of fish-eating birds. The cause of the infestation most likely was the feeding of unfrozen fresh fish. We describe the first case of a lethal I. erraticus infestation in Inca terns.

  2. Powers of nostalgia: Ollanta and the neo-Inca movement

    Directory of Open Access Journals (Sweden)

    Alfredo Cordiviola

    2010-07-01

    Full Text Available This essay analyzes the indigenous rebellions and its evolution in Perú during the XVIII century as well as the functions and impact that nostalgia and utopia had against the mastery of Spanish, keeping in mind that both, nostalgia and utopia, were used like instruments against this movement. The uprising increases due to the abuse of power and the constant inequalities of imperial economy in and around the viceroyalty based on specific unions between social actors. By the year 1780, they conformed a group called broad Inca nationalist movement whose clear expression was showed in the insurrection promoted by Tupac Amaru. We are going to present the possible interpretations to study the evolution of this movement through this project which is related to the history context OLLANTAY. Simultaneously we are going to take advantage of it in order to analyze other texts and arts.

  3. Inca Royal Estates in the Sacred Valley

    Science.gov (United States)

    McKim Malville, J.

    The royal estates lying between Cusco and Machu Picchu illustrate the remarkable variety by which the sun was honored and worshipped in the Inca Empire. The terraced basins of Moray combine the sun at both solstices and, perhaps, the zenith sun, with flowing water and offerings to Pachamama. The complex astronomy at Urubamba involves the palace of Quespiwanka, horizon pillars, solstices, and mountain worship. Ollantaytambo contains horizontal shadow-casting gnomons with a major water shrine.

  4. "Apu Ollantay": Inca Theatre as an example of the modes of interaction between the Incas and Western Amazonian societies

    Directory of Open Access Journals (Sweden)

    Cristiana Bertazoni

    Full Text Available The article looks closely at the Quechua play "Apu Ollantay" in order to better understand the relationships of power that the Incas established with the Amazonian corner of their empire, known in Inca terms as Antisuyu. It is argued that the drama "Apu Ollantay" functioned as a social and political device in order to enhance Inca imperial magnitude and project an image of a magnanimous ruler.

  5. What does Cassini ENA observations tell us about gas around Europa?

    Science.gov (United States)

    Brandt, Pontus; Mauk, Barry; Westlake, Joseph; Smith, Todd; Mitchell, Donald

    2015-04-01

    From about December 2000 to January 2001 the Ion and Neutral Camera (INCA) imaged Jupiter in Energetic Neutral Atoms (ENA) from a distance of about 137-250 Jovian planetary radii (RJ) over an energy range from about 10 to 300 keV. A forward model is employed to derive column densities and assumes a neutral gas-plasma model and an energetic ion distribution based on Galileo in-situ measurements. We demonstrate that Jupiter observations by INCA are consistent with a column density peaking around Europa's orbit in the range from 2x1012 cm-2 to 7x1012 cm-2, assuming H2, and are consistent with the upper limits reported from the Cassini/UVIS observations. Most of the INCA observations are consistent with a roughly azimuthally symmetric gas distribution, but some appear consistent with an asymmetric gas distribution centred on Europa, which would directly imply that Europa is the source of the gas. Although our neutral gas model assumes a Europa source, we explore other explanations of the INCA observations including: (1) ENAs are produced by charge exchange between energetic ions and neutral hydrogen originating from charge-exchanged protons in the Io plasma torus. However, estimated densities by Cheng (1986) are about one order of magnitude too low to explain the INCA observations; (2) ENAs are produced by charge exchange between energetic ions and plasma ions such as O+ and S+ originating from Io. However, that would require O+ plasma densities higher than expected to compensate for the low charge-exchange cross section between protons and O+; (3) We re-examine the INCA Point-Spread Function (PSF) to determine if the ENA emissions in the vicinity of Europa's orbit could be explained by internal scattering of ENAs originating from Jupiter's high-latitude upper atmosphere. However, the PSF was well constrained by using Jupiter from distances where it could be considered a point source.

  6. INCA-CE project: status and results

    Science.gov (United States)

    Strauss, Franziska; Meirold-Mautner, Ingo; Bica, Benedikt; Kann, Alexander; Wang, Yong

    2013-04-01

    Every year, Central Europe (CE) is affected by weather extremes challenging civil protection authorities, hydrologists and road maintenance services to timely warnings. Within the INCA-CE project (Integrated Nowcasting through Comprehensive Analysis in Central Europe; http://www.inca-ce.eu) which is supported by the European Regional Development Fund a deepened transnational cooperation between meteorological/hydrological services and three application areas is established. This guarantees for both enhancements of meteorological products in the sense of end-user friendliness, and standardized information exchange across borders. At present, INCA-CE is the only project throughout the world which connects cooperation to such an extent with respect to its transnational and multidisciplinary framework (in the meanwhile it has been chosen as World Weather Research Programme/Forecast Demonstration Project by the World Meteorological Organization). Key partners from eight countries (from national meteorological/hydrological services and the three different application areas) accept the challenge to work on standardization and harmonization tools. Therefore, the INCA nowcasting system - developed at the Austrian weather service (ZAMG) in the 1990ies - has been implemented at all CE meteorological/hydrological services and is advanced and refined to the specific user needs to (i) provide high quality nowcasting products which are standardized and harmonized across borders, (ii) improve information chains from models to warnings and protection measures in case of disaster, and (iii) make the public and stakeholders more familiar with meteorological products. However, the potential to achieve these listed improvements is only possible through the intense transnational and multidisciplinary cooperation, because for one institution and one country alone it would be impossible to cope with all the necessary tasks. In this presentation the status and results of the INCA

  7. Evaluating the quantity of native H2 in Enceladus' plumes with the Cassini-INMS closed source data: constraints from modeling of ice grains impact in the instrument

    Science.gov (United States)

    Bouquet, A.; Brockwell, T.; Waite, J. H., Jr.; Chocron, S.; Teolis, B. D.; Perryman, R.; Walker, J. D.

    2016-12-01

    The data from the closed source of the Cassini Ion and Neutral Mass Spectrometer (INMS) at Enceladus' plumes shows a signal of H2 in significant quantities (15% mole fraction for low speed flybys). H2 would be considered a "smoking gun" for the suspected hydrothermal activity in Enceladus' ocean. However the H2 quantity varies with the speed of the flyby, which is attributed to the presence of ice grains in the plumes hitting the walls of the titanium antechamber of INMS and exposing fresh titanium that may react with water to form hydrogen. The large number of small ice grains arriving during a single INMS integration period creates a back-ground signal in addition to large grains causing punctual spikes. We have developed a surface chemistry model of the INMS, taking into account adsorption and chemisorption of species of interest to determine how much H2 is produced from the expected ice grains distribution for each flyby (given by Cassini CAPS data ). CTH simulations have been used to assess the contribution of grains of different size in terms of titanium produced. We show that the spikes in the mass 2 channel can be explained by microns-sized grains, and that smaller grains (below 500 nm) are the major contributors to reactions with titanium, accounting for most of the non-spike signal. We find that the mass 2 background signal due to titanium is strongly driven by the water available, and therefore its shape versus time can't follow the sharp rises in the data (see Figure). This makes the structures seen in flyby E18 either the product of several big grains or the observation of locally high density of H2 (jets). We will analyze the effect of grains on other mass channels and comparison to CDA data to de-termine whether the peaks can be attributed to multiple ice grains or to native H2. The work will be extended to the E17 and E14 flybys to reach a definitive assessment of the native H2 abundance in the Enceladus plume.

  8. Cassini's Grand Finale

    Science.gov (United States)

    Spilker, L. J.; Edgington, S. G.; Altobelli, N.

    2016-12-01

    After more than 12 years in Saturn orbit, the Cassini-Huygens mission has entered its final year of data collection. Cassini will return its final bits of unique data on 15 September 2017 as it plunges into Saturn's atmosphere, vaporizing and satisfying planetary protection requirements. Since early 2016 Cassini's orbital inclination was slowly increased towards its final inclination. In November Cassini transitioned to a series of 20 orbits with peripases just outside Saturn's F ring that include some of the closest flybys of the tiny ring moons and excellent views of the F ring and outer A ring. Cassini's final close flyby of Titan will propel it across Saturn's main rings and into its final orbits. Cassini's Grand Finale begins in April 2017 and is comprised of 22 orbits at an inclination of 63 degrees. Cassini will repeatedly dive between the innermost ring and Saturn's upper atmosphere providing insights into fundamental questions unattainable during the rest of the mission. It will be the first spacecraft to explore this region. These close orbits provide the highest resolution observations of both the rings and Saturn, and direct in situ sampling of the ring particles' composition, plasma, Saturn's exosphere and the innermost radiation belts. Saturn's gravitational field will be measured to unprecedented accuracy, providing information on Saturn's interior structure and mass distribution in the rings. Probing the magnetic field will give insight into the nature of the magnetic dynamo and the true rotation rate of Saturn's interior. The ion and neutral mass spectrometer will sniff the exosphere and upper atmosphere and examine water-based molecules originating from the rings. The cosmic dust analyzer will sample particle composition from different parts of the main rings. Recent science highlights and science objectives from Cassini's final orbits will be discussed. This work was carried out in part at the Jet Propulsion Laboratory, California Institute of

  9. Inca Volcanic Stone Provenance in the Cuzco Province, Peru

    Directory of Open Access Journals (Sweden)

    Patrick N. Hunt

    1990-11-01

    Full Text Available The use of andesite and basalt as architectual ashlars by Inca stonemasons has been widely discussed throughout the literature. Most of these archaeological or architectural studies are in agreement that that primary Inca quarrying centers in the Cuzco area are in the Rio Huatanay valley at Rumiqolqa and Huaccoto, both to the southeast of Cuzco.

  10. An Ancient Inca Tax and Metallurgy in Peru

    Science.gov (United States)

    Journal of Chemical Education, 2007

    2007-01-01

    The discovery of ancient Inca tax rulers and other metallurgical objects in Peru show that the ancient civilizations of the country smelted metals. The analysis shows that the smelters in Peru switched from the production of copper to silver after a tax was imposed on them by the Inca rulers.

  11. An Ancient Inca Tax and Metallurgy in Peru

    Science.gov (United States)

    Journal of Chemical Education, 2007

    2007-01-01

    The discovery of ancient Inca tax rulers and other metallurgical objects in Peru show that the ancient civilizations of the country smelted metals. The analysis shows that the smelters in Peru switched from the production of copper to silver after a tax was imposed on them by the Inca rulers.

  12. Guaman Poma's Yupana and Inca Astronomy

    CERN Document Server

    Kak, Subhash

    2014-01-01

    An explanation is provided for the Inca counting board described by Guaman Poma in 1615. Although the board could have been used in more than one way, we show that based on certain reasonable assumptions regarding non-uniform representation of numbers its most likely use was counting in multiples of 6, 24, and 72. The independent numbers represented on its five rows are 92, 31, 29, 79, and 56 that appear to be astronomically connected to sub-periods within the year and planet periods in a manner similar to Mayan astronomy. Based on these and other considerations we propose that the board fulfilled an astronomical counting function.

  13. Cassini's remote sensing pallet is installed in the PHSF

    Science.gov (United States)

    1997-01-01

    Technicians from the Jet Propulsion Laboratory (JPL) of the California Institute of Technology lift the remote sensing pallet in the Payload Hazardous Servicing Facility at KSC in July prior to installation on the Cassini spacecraft. A four- year, close-up study of the Saturnian system, the Cassini mission is scheduled for launch from Cape Canaveral Air Station in October 1997. It will take seven years for the spacecraft to reach Saturn. Scientific instruments carried aboard the spacecraft will study Saturn's atmosphere, magnetic field, rings, and several moons. JPL is managing the Cassini project for NASA.

  14. Counting and Arithmetic of the Inca

    Directory of Open Access Journals (Sweden)

    Ximena Catepillán

    2012-01-01

    Full Text Available El Imperio Inca ¿ el imperio pre-Colombino más grande del continente Americano ¿ se extendió desde Ecuador hasta Chile central por más de cinco mil millas. La capital fue Cuzco, la que fue establecida en las Alturas de los Andes Peruanos. Esta civilización altamente avanzada desarrolló un sistema contable para organizar el imperio ¿ en particular, para construir una red de caminos de 14.000 millas y una arquitectura monumental. Algunos de los algoritmos que se creen haber sido usados por los Inca para hacer cálculos fue la "yupana". Este antiguo artefacto de cálculo será presentado, entre otras actividades del curso "Matemáticas en Culturas No-Europeas" para estudiantes de todas las áreas de concentración, excepto Matemáticas y Ciencia, ofrecido en la Universidad de Millersville en Pennsylvania.

  15. Pre-Inca Astronomy in Peru

    Science.gov (United States)

    McKim Malville, J.

    Huacas (shrines) and ushnus (ceremonial platforms) are ever-present elements of millennia-old Andean cosmology extending backward to 3100 BCE. Major themes of Pan-Andean cosmology include sacred mountains, the power of water, the solstice sun, as well as shamanic-like movement across the three worlds of the cosmos. Common features of many pre-Inca sites are monumental platforms and sunken circular plazas, and stairways with axes established by bi-lateral symmetries oriented along solstice lines. This style of ritual architecture first appeared in Chupacigarro/Caral, other sites in the Norte Chico area, and Sechin Bajo in the Casma Valley. Ceremonial plazas provided opportunities for public viewing of ritual ceremonies on the tops of platforms, which may have been understood as sacred mountains. Mounds and temples of the Casma Valley, such as Sechin Alto, Sechin Bajo, and Chankillo, developed an explicit astronomy associated with June and December solstices. The ritualistic use of water, which is typically associated with visual astronomy at Inca sites, appeared at Chavin de Huantar and later in Tiwanaku.

  16. En-INCA: Towards an integrated probabilistic nowcasting system

    Science.gov (United States)

    Suklitsch, Martin; Stuhl, Barbora; Kann, Alexander; Bica, Benedikt

    2014-05-01

    INCA (Integrated Nowcasting through Comprehensive Analysis), the analysis and nowcasting system operated by ZAMG, is based on blending observations and NWP data. Its performance is extremely high in the nowcasting range. However, uncertainties can be large even in the very short term and limit its practical use. Severe weather conditions are particularly demanding, which is why the quantification of uncertainties and determining probabilities of event occurrences are adding value for various applications. The Nowcasting Ensemble System En-INCA achieves this by coupling the INCA nowcast with ALADIN-LAEF, the EPS of the local area model ALADIN operated at ZAMG successfully for years already. In En-INCA, the Nowcasting approach of INCA is blended with different EPS members in order to derive an ensemble of forecasts in the nowcasting range. In addition to NWP based uncertainties also specific perturbations with respect to observations, the analysis and nowcasting techniques are discussed, and the influence of learning from errors in previous nowcasts is shown. En-INCA is a link between INCA and ALADIN-LAEF by merging the advantages of both systems: observation based nowcasting at very high resolution on the one hand and the uncertainty estimation of a state-of-the-art LAM-EPS on the other hand. Probabilistic nowcasting products can support various end users, e.g. civil protection agencies and power industry, to optimize their decision making process.

  17. Normal IncA Expression and Fusogenicity of Inclusions in Chlamydia trachomatis Isolates with the incA I47T Mutation

    OpenAIRE

    Pannekoek, Yvonne; van der Ende, Arie; Eijk, Paul P.; van Marle, Jan; de Witte, Moniek A.; Ossewaarde, Jacobus M.; Van Den Brule, Adriaan J. C.; Morré, Servaas A.; Dankert, Jacob

    2001-01-01

    To investigate the correlation between the incA I47T mutation in Chlamydia trachomatis and the nonfusogenic phenotype, the incA genes of 25 isolates were sequenced. Four major sequence types were identified. Seven isolates (28%) had the I47T mutation. Isolates representing the four sequence types expressed IncA in the membrane of one large single inclusion. In conclusion, the incA I47T mutation is not associated with the nonfusogenic phenotype.

  18. Composite Infrared Spectrometer (CIRS) on Cassini

    Science.gov (United States)

    Jennings, Donald E.; Flasar, F. M.; Kunde, V. G.; Nixon, C. A.; Segura, M. E.; Romani, P. N.; Gorius, N.; Albright, S.; Brasunas, J. C.; Carlson, R. C.; hide

    2017-01-01

    The Cassini spacecraft orbiting Saturn carries the composite infrared spectrometer (CIRS) designed to study thermal emission from Saturn and its rings and moons. CIRS, a Fourier transform spectrometer, is an indispensable part of the payload providing unique measurements and important synergies with the other instruments. It takes full advantage of Cassini's 13-year-long mission and surpasses the capabilities of previous spectrometers on Voyager 1 and 2. The instrument, consisting of two interferometers sharing a telescope and a scan mechanism, covers over a factor of 100 in wavelength in the mid and far infrared. It is used to study temperature, composition, structure, and dynamics of the atmospheres of Jupiter, Saturn, and Titan, the rings of Saturn, and surfaces of the icy moons. CIRS has returned a large volume of scientific results, the culmination of over 30 years of instrument development, operation, data calibration, and analysis. As Cassini and CIRS reach the end of their mission in 2017, we expect that archived spectra will be used by scientists for many years to come.

  19. El kero : vaso ritual de los incas

    Directory of Open Access Journals (Sweden)

    Alicia Alonso Sagaseta

    1990-01-01

    Full Text Available Cuando en los museos de todo el mundo encontramos colecciones de arqueología americana, es bastante habitual que nos llame la atención, la presencia de un tipo de recipiente de madera, de forma troncocónica y decoración en laca que relata de manera ingenua acontecimientos de distinta índole; nos referimos a los llamados «Keros« de la cultura Inca. Nuestros trabajos en los fondos del Museo de América de Madrid, del Museo del Hombre en París y del Museo Arqueológico de Lima, nos dieron la oportunidad de conocer estos recipientes mucho más de cerca, y a partir de este momento plantearnos una serie de interrogantes respecto a ellos.

  20. Cassini Information Management System in Distributed Operations Collaboration and Cassini Science Planning

    Science.gov (United States)

    Equils, Douglas J.

    2008-01-01

    Launched on October 15, 1997, the Cassini-Huygens spacecraft began its ambitious journey to the Saturnian system with a complex suite of 12 scientific instruments, and another 6 instruments aboard the European Space Agencies Huygens Probe. Over the next 6 1/2 years, Cassini would continue its relatively simplistic cruise phase operations, flying past Venus, Earth, and Jupiter. However, following Saturn Orbit Insertion (SOI), Cassini would become involved in a complex series of tasks that required detailed resource management, distributed operations collaboration, and a data base for capturing science objectives. Collectively, these needs were met through a web-based software tool designed to help with the Cassini uplink process and ultimately used to generate more robust sequences for spacecraft operations. In 2001, in conjunction with the Southwest Research Institute (SwRI) and later Venustar Software and Engineering Inc., the Cassini Information Management System (CIMS) was released which enabled the Cassini spacecraft and science planning teams to perform complex information management and team collaboration between scientists and engineers in 17 countries. Originally tailored to help manage the science planning uplink process, CIMS has been actively evolving since its inception to meet the changing and growing needs of the Cassini uplink team and effectively reduce mission risk through a series of resource management validation algorithms. These algorithms have been implemented in the web-based software tool to identify potential sequence conflicts early in the science planning process. CIMS mitigates these sequence conflicts through identification of timing incongruities, pointing inconsistencies, flight rule violations, data volume issues, and by assisting in Deep Space Network (DSN) coverage analysis. In preparation for extended mission operations, CIMS has also evolved further to assist in the planning and coordination of the dual playback redundancy of

  1. Exploration of the Saturn System by the Cassini Mission: Observations with the Cassini Infrared Spectrometer

    Science.gov (United States)

    Abbas, Mian M.

    2014-01-01

    The Cassini mission is a joint NASA-ESA international mission, launched on October 17, 1997 with 12 instruments on board, for exploration of the Saturn system. A composite Infrared Spectrometers is one of the major instruments. Successful insertion of the spacecraft in Saturn's orbit for an extended orbital tour occurred on July 1, 2004. The French Huygens-Probe on board, with six instruments was programmed for a soft landing on Titan's surface occurred in January 2005. The broad range scientific objectives of the mission are: Exploration of the Saturn system for investigations of the origin, formation, & evolution of the solar system, with an extensive range of measurements and the analysis of the data for scientific interpretations. The focus of research dealing with the Cassini mission at NASA/MSFC in collaboration with the NASA/Goddard Space Flight Center, JPL, as well as the research teams at Oxford/UK and Meudon Observatory/France, involves the Infrared observations of Saturn and its satellites, for measurements of the thermal structure and global distributions of the atmospheric constituents. A brief description of the Cassini spacecraft, the instruments, the objectives, in particular with the infrared observations of the Saturn system will be given. The analytical techniques for infrared radiative transfer and spectral inversion programs, with some selected results for gas constituent distributions will be presented.

  2. The INCA Project II. Measurements of the neutron yield from a lead absorber for pion and proton projectiles

    Science.gov (United States)

    INCA Collaboration

    1999-08-01

    As a part of the program of development of a new instrument called Ionization- Neutron Calorimeter (INCA) aimed at studying primary cosmic radiation, exp erimental data on average values and fluctuations of the neutron yield from a 60-cm-thick lead target are obtained. The target was exposed to pion and proton accelerator b eams with energies of 4 and 70 GeV, resp ectively, and to an electron beam with an energy of 200 to 550 MeV. The exp erimental data obtained well agree with the results of a simulation by the SHIELD code used for development of INCA elements. It is shown that the same particle energy, the average neutron yield for electron pro jectiles is by the factor of approximately 50 lower than for hadrons.

  3. Instrumentation

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Journal Scope:Instrumentation is a high quality open access peer reviewed research journal.Authors are solicited to contribute to these journals by submitting articles that illustrate most up-to-date research results,projects,surveying works and industrial experiences that describe significant advances in the instrumental science.The mission of the Instrumentation is

  4. Cassini launch contingency effort

    Science.gov (United States)

    Chang, Yale; O'Neil, John M.; McGrath, Brian E.; Heyler, Gene A.; Brenza, Pete T.

    2002-01-01

    On 15 October 1997 at 4:43 AM EDT, the Cassini spacecraft was successfully launched on a Titan IVB/Centaur on a mission to explore the Saturnian system. It carried three Radioisotope Thermoelectric Generators (RTGs) and 117 Light Weight Radioisotope Heater Units (LWRHUs). As part of the joint National Aeronautics and Space Administration (NASA)/U.S. Department of Energy (DoE) safety effort, a contingency plan was prepared to address the unlikely events of an accidental suborbital reentry or out-of-orbital reentry. The objective of the plan was to develop procedures to predict, within hours, the Earth impact footprints (EIFs) for the nuclear heat sources released during the atmospheric reentry. The footprint predictions would be used in subsequent notification and recovery efforts. As part of a multi-agency team, The Johns Hopkins University Applied Physics Laboratory (JHU/APL) had the responsibility to predict the EIFs of the heat sources after a reentry, given the heat sources' release conditions from the main spacecraft. (No ablation burn-through of the heat sources' aeroshells was expected, as a result of earlier testing.) JHU/APL's other role was to predict the time of reentry from a potential orbital decay. The tools used were a three degree-of-freedom trajectory code, a database of aerodynamic coefficients for the heat sources, secure links to obtain tracking data, and a high fidelity special perturbation orbit integrator code to predict time of spacecraft reentry from orbital decay. In the weeks and days prior to launch, all the codes and procedures were exercised. Notional EIFs were derived from hypothetical reentry conditions. EIFs predicted by JHU/APL were compared to those by JPL and US SPACECOM, and were found to be in good agreement. The reentry time from orbital decay for a booster rocket for the Russian Progress M-36 freighter, a cargo ship for the Mir space station, was predicted to within 5 minutes more than two hours before reentry. For the

  5. Cassini at Saturn Huygens results

    CERN Document Server

    Harland, David M

    2007-01-01

    "Cassini At Saturn - Huygens Results" will bring the story of the Cassini-Huygens mission and their joint exploration of the Saturnian system right up to date. Cassini is due to enter orbit around Saturn on the 1 July 2004 and the author will have 8 months of scientific data available for review, including the most spectacular images of Saturn, its rings and satellites ever obtained by a space mission. As the Cassini spacecraft approached its destination in spring 2004, the quality of the images already being returned by the spacecraft clearly demonstrate the spectacular nature of the close-range views that will be obtained. The book will contain a 16-page colour section, comprising a carefully chosen selection of the most stunning images to be released during the spacecraft's initial period of operation. The Huygens craft will be released by Cassini in December 2004 and is due to parachute through the clouds of Saturn's largest moon, Titan, in January 2005.

  6. Cassini Mission. (Latest citations from the EI Compendex*Plus database)

    Science.gov (United States)

    1996-01-01

    The bibliography contains citations concerning the Cassini mission to the Saturnian system. Topics include radar instrumentation, altimetry, and model testing, and reference the Voyager and Galileo missions. The interplanetary trajectory design process is discussed.

  7. Inca expansion and parasitism in the Lluta Valley: preliminary data

    Directory of Open Access Journals (Sweden)

    Santoro Calogero

    2003-01-01

    Full Text Available Assessing the impact of cultural change on parasitism has been a central goal in archaeoparasitology. The influence of civilization and the development of empires on parasitism has not been evaluated. Presented here is a preliminary analysis of the change in human parasitism associated with the Inca conquest of the Lluta Valley in Northern Chile. Changes in parasite prevalence are described. It can be seen that the change in life imposed on the inhabitants of the Lluta Valley by the Incas caused an increase in parasitism.

  8. Inca Moon: Some Evidence of Lunar Observations in Tahuantinsuyu

    Science.gov (United States)

    Ziółkowski, Mariusz; Kościuk, Jacek; Astete, Fernando

    So far, scientists have not investigated thoroughly if and for what purpose the Incas observed the Moon. As far as the orientation of architectural structures is concerned, the researchers focus their attention almost entirely on the position of the Sun. However, a more accurate analysis of two well-known sites - the caves of Intimachay and Cusilluchayoc - may provide evidence of their function as observatories of the lunar 18.6-year cycle. Those results may confirm the hypothesis, presented some years ago, that the Incas had elaborated a rudimentary method of predicting lunar eclipses.

  9. Instrumentation

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    Journal Scope:Instrumentation is a high quality open access peer reviewed research journal.Authors are solicited to contribute to these journals by submitting articles that illustrate most up-to-date research results,projects,surveying works and industrial experiences that describe significant advances in the instrumental science.The mission of the Instrumentation is to provide a platform for the researchers,academicians,

  10. Instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    Decreton, M

    2001-04-01

    SCK-CEN's research and development programme on instrumentation involves the assessment and the development of sensitive measurement systems used within a radiation environment. Particular emphasis is on the assessment of optical fibre components and their adaptability to radiation environments. The evaluation of ageing processes of instrumentation in fission plants, the development of specific data evaluation strategies to compensate for ageing induced degradation of sensors and cable performance form part of these activities. In 2000, particular emphasis was on in-core reactor instrumentation applied to fusion, accelerator driven and water-cooled fission reactors. This involved the development of high performance instrumentation for irradiation experiments in the BR2 reactor in support of new instrumentation needs for MYRRHA, and for diagnostic systems for the ITER reactor.

  11. The Saturn System's Icy Satellites: New Results from Cassini

    Science.gov (United States)

    Lopes-Gautier, Rosaly M.; Buratti, Bonnie; Hendrix, A. R.

    2008-01-01

    Cassini-Huygens is a multidisciplinary, international planetary mission consisting of an orbiting spacecraft and a probe. The Huygens probe successfully landed on Titan's surface on January 14, 2005, while the orbiter has performed observations of Saturn, its rings, satellites, and magnetosphere since it entered orbit around Saturn on July 1, 2004. The Cassini mission has been prolific in its scientific discoveries about the Saturn system. In this special section, we present new mission results with a focus on the 'icy satellites,' which we define as all Saturn's moons with the exception of Titan. The results included in this section have come out of the Cassini SOST--Satellites Orbiter Science Team--a multi-instrument and multidiscipline group that works together to better understand the icy satellites and their interactions with Saturn and its rings. Other papers included in this issue present ground-based observations and interior modeling of these icy moons.

  12. Automation of Cassini Support Imaging Uplink Command Development

    Science.gov (United States)

    Ly-Hollins, Lisa; Breneman, Herbert H.; Brooks, Robert

    2010-01-01

    "Support imaging" is imagery requested by other Cassini science teams to aid in the interpretation of their data. The generation of the spacecraft command sequences for these images is performed by the Cassini Instrument Operations Team. The process initially established for doing this was very labor-intensive, tedious and prone to human error. Team management recognized this process as one that could easily benefit from automation. Team members were tasked to document the existing manual process, develop a plan and strategy to automate the process, implement the plan and strategy, test and validate the new automated process, and deliver the new software tools and documentation to Flight Operations for use during the Cassini extended mission. In addition to the goals of higher efficiency and lower risk in the processing of support imaging requests, an effort was made to maximize adaptability of the process to accommodate uplink procedure changes and the potential addition of new capabilities outside the scope of the initial effort.

  13. El Camino Inca de la Costa en Tumbes

    OpenAIRE

    Vílchez Carrasco, Carolina; Ministerio de Cultura

    2015-01-01

    Artículo descriptivo sobre el camino inca de la costa de Tumbes y sus tres subtramos: en la cordillera de Amotapes, en las colinas miocénicas y en la planicie litoral. Abarca temas como el medio geográfico, los antecedentes del estudio y la historia del tramo.

  14. Instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    Decreton, M

    2002-04-01

    SCK-CEN's R and D programme on instrumentation involves the development of advanced instrumentation systems for nuclear applications as well as the assessment of the performance of these instruments in a radiation environment. Particular emphasis is on the use of optical fibres as umbilincal links of a remote handling unit for use during maintanance of a fusion reacor, studies on the radiation hardening of plasma diagnostic systems; investigations on new instrumentation for the future MYRRHA accelerator driven system; space applications related to radiation-hardened lenses; the development of new approaches for dose, temperature and strain measurements; the assessment of radiation-hardened sensors and motors for remote handling tasks and studies of dose measurement systems including the use of optical fibres. Progress and achievements in these areas for 2001 are described.

  15. Instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    Decreton, M

    2000-07-01

    SCK-CEN's research and development programme on instrumentation aims at evaluating the potentials of new instrumentation technologies under the severe constraints of a nuclear application. It focuses on the tolerance of sensors to high radiation doses, including optical fibre sensors, and on the related intelligent data processing needed to cope with the nuclear constraints. Main achievements in these domains in 1999 are summarised.

  16. historia en el Inca Garcilaso de la Vega

    Directory of Open Access Journals (Sweden)

    Jorge Majfud

    2007-01-01

    Full Text Available Existen varios elementos ideológicos en la narración histórica del Inca Garcilaso de la Vega y una concepción de progreso de la historia que se opone a la más antigua de Hesíodo y de la Iglesia. En sus Comentarios Reales de los Incas procura una reivindicación de su pueblo original, en un contexto español; para ser aceptado, se propone no reescribir directamente la historia oficial, pero trastoca los significados de aquellos “hechos” narrados con anterioridad por los españoles en su Perú natal. Al mismo tiempo, realiza un mestizaje cosmológico que servirá como herramienta para confirmar su concepción de la historia y reivindicar, al mismo tiempo, sus orígenes étnicos y culturales. Pero, en gran medida, su perspectiva religiosa e intelectual ya pertenece a España. El Inca Garcilaso de la Vega no reconoce el panteísmo de los preincaicos y lo rechaza desde una perspectiva cristiana que separa al hombre de la naturaleza, lo que demuestra su concepción europea de la divinidad. Desprecia las culturas preincaicas porque adoraban lo inferior a ellos, mientras que los Incas –como los cristianos– adoraban lo superior y la unidad: el Sol. Más aún, Garcilaso de la Vega identifica, sin nombrarlo, al Sol con Dios y a Pachacámac con el Espíritu Santo. Jesu Christo será la culminación del progreso hacia la perfección de la Trinidad. La consecuencia es una concepción progresista de la historia que incluye a los incas y todos los pueblos (imperfectos que los precedieron. Pasa por encima del rito, del dogma y de las formas para encontrar en el pueblo inca un destino común a la civilización cristiana. Con ello también revela un componente humanista de una historia que se desarrolla con un objetivo universal y mestizo. No por casualidad, se nombra “Inca” con un apellido español, de la Vega, y lucha por conciliar ambas tradiciones: es un proyecto histórico, una voluntad de síntesis y una reivindicación personal.

  17. Cassini Mission Sequence Subsystem (MSS)

    Science.gov (United States)

    Alland, Robert

    2011-01-01

    This paper describes my work with the Cassini Mission Sequence Subsystem (MSS) team during the summer of 2011. It gives some background on the motivation for this project and describes the expected benefit to the Cassini program. It then introduces the two tasks that I worked on - an automatic system auditing tool and a series of corrections to the Cassini Sequence Generator (SEQ_GEN) - and the specific objectives these tasks were to accomplish. Next, it details the approach I took to meet these objectives and the results of this approach, followed by a discussion of how the outcome of the project compares with my initial expectations. The paper concludes with a summary of my experience working on this project, lists what the next steps are, and acknowledges the help of my Cassini colleagues.

  18. NASA 3D Models: Cassini

    Data.gov (United States)

    National Aeronautics and Space Administration — Cassini spacecraft from SPACE rendering package, built by Michael Oberle under NASA contract at JPL. Includes orbiter only, Huygens probe detached. Accurate except...

  19. Titan from Cassini-Huygens

    CERN Document Server

    Brown, Robert H; Waite, J. Hunter

    2010-01-01

    This book reviews our current knowledge of Saturn's largest moon Titan featuring the latest results obtained by the Cassini-Huygens mission. A global author team addresses Titan’s origin and evolution, internal structure, surface geology, the atmosphere and ionosphere as well as magnetospheric interactions. The book closes with an outlook beyond the Cassini-Huygens mission. Colorfully illustrated, this book will serve as a reference to researchers as well as an introduction for students.

  20. Cassini Tour Atlas Automated Generation

    Science.gov (United States)

    Grazier, Kevin R.; Roumeliotis, Chris; Lange, Robert D.

    2011-01-01

    During the Cassini spacecraft s cruise phase and nominal mission, the Cassini Science Planning Team developed and maintained an online database of geometric and timing information called the Cassini Tour Atlas. The Tour Atlas consisted of several hundreds of megabytes of EVENTS mission planning software outputs, tables, plots, and images used by mission scientists for observation planning. Each time the nominal mission trajectory was altered or tweaked, a new Tour Atlas had to be regenerated manually. In the early phases of Cassini s Equinox Mission planning, an a priori estimate suggested that mission tour designers would develop approximately 30 candidate tours within a short period of time. So that Cassini scientists could properly analyze the science opportunities in each candidate tour quickly and thoroughly so that the optimal series of orbits for science return could be selected, a separate Tour Atlas was required for each trajectory. The task of manually generating the number of trajectory analyses in the allotted time would have been impossible, so the entire task was automated using code written in five different programming languages. This software automates the generation of the Cassini Tour Atlas database. It performs with one UNIX command what previously took a day or two of human labor.

  1. Instruments

    Energy Technology Data Exchange (ETDEWEB)

    Buehrer, W. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1996-12-31

    The present paper mediates a basic knowledge of the most commonly used experimental techniques. We discuss the principles and concepts necessary to understand what one is doing if one performs an experiment on a certain instrument. (author) 29 figs., 1 tab., refs.

  2. Instrumentation

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Journal Scope:Instrumentation is a high quality open access peer reviewed research journal,Authors are solicited to contribute to these journals by submitting articles that illustrate most up-to-date research results,projects,surveying works and industrial

  3. A Traveling Exhibit of Cassini Image Science

    Science.gov (United States)

    Burns, Joseph A.; Hedman, M. M.; Tiscareno, M. S.; Ebel, D.; Mac Low, M.; Lovett, L. E.; Burns, J. K.; Schaff, N.; Bilson, E. M.

    2007-10-01

    An exhibit of Cassini's images will open at NYC's American Museum of Natural History in March 2008 and then visit the Johnson Art Museum (Cornell) throughout fall 2008, including during next year's DPS. It is under consideration by several other venues in the States and overseas. The exhibit will feature 40-50 images, ranging from letter size to large posters, taken by remote-sensing instruments aboard Cassini and Huygens. Photos will be organized into a half-dozen thematic clusters (e.g., organized by celestial target or by physical process); a panel will introduce each grouping with individual images identified briefly. The Saturn system is a perfect vehicle to educate citizens about planetary science and origins. The images’ beauty should capture the public's attention, allowing us to then engage their curiosity about the relevant science. Among the Saturn system's broad suite of objects are Enceladus and Titan, two satellites of astrobiological interest; moreover, the rings display many processes active in other astrophysical disks. Several auxiliary ideas will be implemented. In Ithaca, we will project images at night against the museum's sand-colored exterior walls. A 10-12 minute musical composition has been commissioned from Roberto Sierra to open the show. We will encourage school children to participate in a human orrery circling the museum and will seek volunteers to participate in several Saturnalia. At Cornell we will involve the university and local communities, by taping their reactions to the images’ exquisite beauty as well as to their scientific content. Cassini will be the E/PO focus of next year's DPS meeting; those materials will be employed throughout the fall at New York schools and be available to travel with the show. We intend to work with NYC partners to offer teacher credits for associated weekend courses. We will produce classroom materials, including a DVD, for teacher use.

  4. Conservation of the biochemical properties of IncA from Chlamydia trachomatis and Chlamydia caviae: oligomerization of IncA mediates interaction between facing membranes.

    Science.gov (United States)

    Delevoye, Cédric; Nilges, Michael; Dautry-Varsat, Alice; Subtil, Agathe

    2004-11-05

    The developmental cycle of Chlamydiaceae occurs in a membrane compartment called an inclusion. IncA is a member of a family of proteins synthesized and secreted onto the inclusion membrane by bacteria. IncA proteins from different species of Chlamydiaceae show little sequence similarity. We report that the biochemical properties of Chlamydia trachomatis and Chlamydia caviae are conserved. Both proteins self-associate to form multimers. When artificially expressed by the host cell, they localize to the endoplasmic reticulum. Strikingly, heterologous expression of IncA in the endoplasmic reticulum completely inhibits concomitant inclusion development. Using truncated forms of IncA from C. caviae, we show that expression of the C-terminal cytoplasmic domain of the protein at the surface of the endoplasmic reticulum is sufficient to disrupt the bacterial developmental cycle. On the other hand, development of a C. trachomatis strain that does not express IncA is not inhibited by artificial IncA expression, showing that the disruptive effect observed with the wild-type strain requires direct interactions between IncA molecules at the inclusion and on the endoplasmic reticulum. Finally, we modeled IncA tetramers in parallel four helix bundles based on the structure of the SNARE complex, a conserved structure involved in membrane fusion in eukaryotic cells. Both C. trachomatis and C. caviae IncA tetramers were highly stable in this model. In conclusion, we show that the property of IncA proteins to assemble into multimeric structures is conserved between chlamydial species, and we propose that these proteins may have co-evolved with the SNARE machinery for a role in membrane fusion.

  5. Cassini's remote sensing pallet is mated to the spacecraft in the PHSF

    Science.gov (United States)

    1997-01-01

    The complete remote sensing pallet is lowered by technicians from the Jet Propulsion Laboratory (JPL) of the California Institute of Technology and mated at the interface with the Cassini spacecraft in the Payload Hazardous Servicing Facility at KSC in July. A four-year, close-up study of the Saturnian system, the Cassini mission is scheduled for launch from Cape Canaveral Air Station in October 1997. It will take seven years for the spacecraft to reach Saturn. Scientific instruments carried aboard the spacecraft will study Saturn's atmosphere, magnetic field, rings, and several moons. JPL is managing the Cassini project for NASA.

  6. Cassini's remote sensing pallet is prepared for installation in the PHSF

    Science.gov (United States)

    1997-01-01

    The complete remote sensing pallet is lowered by technicians from the Jet Propulsion Laboratory (JPL) of the California Institute of Technology to mate with the Cassini spacecraft in the Payload Hazardous Servicing Facility at KSC in July. A four-year, close- up study of the Saturnian system, the Cassini mission is scheduled for launch from Cape Canaveral Air Station in October 1997. It will take seven years for the spacecraft to reach Saturn. Scientific instruments carried aboard the spacecraft will study Saturn's atmosphere, magnetic field, rings, and several moons. JPL is managing the Cassini project for NASA.

  7. The Cassini-Huygens mission

    CERN Document Server

    The joint NASA-ESA Cassini-Huygens mission promises to return four (and possibly more) years of unparalleled scientific data from the solar system’s most exotic planet, the ringed, gas giant, Saturn. Larger than Galileo with a much greater communication bandwidth, Cassini can accomplish in a single flyby what Galileo returned in a series of passes. Cassini explores the Saturn environment in three dimensions, using gravity assists to climb out of the equatorial plane to look down on the rings from above, to image the aurora and to study polar magnetospheric processes such as field-aligned currents. Since the radiation belt particle fluxes are much more benign than those at Jupiter, Cassini can more safely explore the inner regions of the magnetosphere. The spacecraft approaches the planet closer than Galileo could, and explores the inner moons and the rings much more thoroughly than was possible at Jupiter. This book is the second volume, in a three volume set, that describes the Cassini/Huygens mission. Thi...

  8. Interrelationship between polymorphisms of incA, fusogenic properties of Chlamydia trachomatis strains, and clinical manifestations in patients in The Netherlands.

    Science.gov (United States)

    Pannekoek, Yvonne; Spaargaren, Joke; Langerak, Ankie A J; Merks, Judith; Morré, Servaas A; van der Ende, Arie

    2005-05-01

    IncA variation among Dutch Chlamydia trachomatis isolates was investigated. Of 98 strains, two carried an incA with a premature stop codon, lacked IncA, and were nonfusogenic, while 96 contained an intact incA, expressed IncA, and were fusogenic. Among these 96 strains, nine IncA sequence types were found, of which the three most frequently encountered (88% of the strains) were randomly distributed among symptomatic and asymptomatic patients.

  9. An Overview of Cassini Radio Science

    Science.gov (United States)

    Kliore, A.; Rappaport, N.; Anabtawi, A.; Asmar, S.; Armstrong, J.; Barbinis, E.; Goltz, G.; Johnston, D.; Fleischman, D.; Rochblatt, D.; Anderson, J.; Marouf, E.; Wong, K.; Thomson, F.; Flasar, F. M.; Schinder, P.; French, R.; McGhee, C.; Mohammed, P.; Steffes, P.; Nagy, A.; Iess, L.; Tortora, P.; Ambrosini, R.; Flamini, E.

    2005-08-01

    The Cassini spacecraft, which has been in orbit about Saturn for over a year, is the first Radio Science platform to provide three downlink frequencies. In addition to the X-band telemetry link (3,56 cm w.l.), two other frequencies, S-band (13.04 cm), and Ka-band (0.94 cm) are available. This, plus the high SNR (>50 dBHz at X-band) afforded by the 4 m diameter s/c high gain antenna in combination with the excellent low noise receivers of the DSN, as well as overall system stabilities of 1 x 10-13 when referenced to the on-board ultra-stable oscillator (USO) in one-way operation, and 1 x 10-15 for a two-way link, make Cassini an unprecedented instrument of radio science. In addition to Gravitational Wave Search and Solar Conjunction experiments conducted during the cruise phase, the orbital tour phase of the mission has as its main radio science objectives: a) determination of the masses and gravity fields of Saturn's icy satellites, Titan, and Saturn through two-way tracking during fly-bys. To date, the masses of Phoebe, Iapetus, Dione and Enceladus have been measured, and will be reported here. b) Measurement of the structure and other properties of Saturn's rings through three-band occultation. Several near-diametric occultations at a high ring opening angle have been completed, and the results will be presented here. c) Measurement of the vertical structure of the atmosphere and ionosphere of Saturn. The same series of occultations have provided nearly equatorial occultations, and the results on the atmosphere structure, the ionosphere, and the abundances of microwave-absorbing gases in Saturn's atmosphere will be described here. In the remaining years of the Cassini mission, these results will be expanded to include the atmosphere, ionosphere, surface, and gravity field of Titan, the gravity field and masses of Saturn and the remaining icy satellites, and the completion of the Saturn objectives described above. The Cassini Radio Science Team wishes to express

  10. Towards an integrated probabilistic nowcasting system (En-INCA)

    Science.gov (United States)

    Suklitsch, M.; Kann, A.; Bica, B.

    2015-04-01

    Ensemble prediction systems are becoming of more and more interest for various applications. Especially ensemble nowcasting systems are increasingly requested by different end users. In this study we introduce such an integrated probabilistic nowcasting system, En-INCA. In a case study we show the added value and increased skill of the new system and demonstrate the improved performance in comparison with a state-of-the-art LAM-EPS.

  11. 'Inca City' is Part of a Circular Feature

    Science.gov (United States)

    2002-01-01

    MGS MOC Release No. MOC2-319, 8 August 2002 [figure removed for brevity, see original site] 'Inca City' is the informal name given by Mariner 9 scientists in 1972 to a set of intersecting, rectilinear ridges that are located among the layered materials of the south polar region of Mars. Their origin has never been understood; most investigators thought they might be sand dunes, either modern dunes or, more likely, dunes that were buried, hardened, then exhumed. Others considered them to be dikes formed by injection of molten rock (magma) or soft sediment into subsurface cracks that subsequently hardened and then were exposed at the surface by wind erosion. The Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) has provided new information about the 'Inca City' ridges, though the camera's images still do not solve the mystery. The new information comes in the form of a MOC red wide angle context frame taken in mid-southern spring, shown above left and above right. The original Mariner 9 view of the ridges is seen at the center. The MOC image shows that the 'Inca City' ridges, located at 82oS, 67oW, are part of a larger circular structure that is about 86 km (53 mi) across. It is possible that this pattern reflects an origin related to an ancient, eroded meteor impact crater that was filled-in, buried, then partially exhumed. In this case, the ridges might be the remains of filled-in fractures in the bedrock into which the crater formed, or filled-in cracks within the material that filled the crater. Or both explanations could be wrong. While the new MOC image shows that 'Inca City' has a larger context as part of a circular form, it does not reveal the exact origin of these striking and unusual martian landforms.

  12. 'Inca City' is Part of a Circular Feature

    Science.gov (United States)

    2002-01-01

    MGS MOC Release No. MOC2-319, 8 August 2002 [figure removed for brevity, see original site] 'Inca City' is the informal name given by Mariner 9 scientists in 1972 to a set of intersecting, rectilinear ridges that are located among the layered materials of the south polar region of Mars. Their origin has never been understood; most investigators thought they might be sand dunes, either modern dunes or, more likely, dunes that were buried, hardened, then exhumed. Others considered them to be dikes formed by injection of molten rock (magma) or soft sediment into subsurface cracks that subsequently hardened and then were exposed at the surface by wind erosion. The Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) has provided new information about the 'Inca City' ridges, though the camera's images still do not solve the mystery. The new information comes in the form of a MOC red wide angle context frame taken in mid-southern spring, shown above left and above right. The original Mariner 9 view of the ridges is seen at the center. The MOC image shows that the 'Inca City' ridges, located at 82oS, 67oW, are part of a larger circular structure that is about 86 km (53 mi) across. It is possible that this pattern reflects an origin related to an ancient, eroded meteor impact crater that was filled-in, buried, then partially exhumed. In this case, the ridges might be the remains of filled-in fractures in the bedrock into which the crater formed, or filled-in cracks within the material that filled the crater. Or both explanations could be wrong. While the new MOC image shows that 'Inca City' has a larger context as part of a circular form, it does not reveal the exact origin of these striking and unusual martian landforms.

  13. Inca - interparietal bones in neurocranium of human skulls in central India.

    Science.gov (United States)

    Marathe, Rr; Yogesh, As; Pandit, Sv; Joshi, M; Trivedi, Gn

    2010-01-01

    Inca bones are accessory bones found in neurocranium of human skulls. Occurrence of Inca bones is rare as compared to other inter sutural bones such as wormian bones. These Inca ossicles are regarded as variants of the normal. The reporting of such occurrences is inadequate from Central India. To find the incidence of Inca variants in Central India. In the present study, 380 dried adult human skulls were examined. All specimen samples were procured from various Medical colleges of Central India. They were analyzed for gross incidence, sexual dimorphism and number of fragments of Inca bones. Gross incidence of Inca bones was found to be 1.315 %. Incidence rate was higher in male skulls than female skulls (male: 1.428%; female: 1.176%). The Inca bones frequently occurred signally. Out of the five observed Inca ossicles, two were fragmented. This data gives idea regarding gross incidence, sexual dimorphism and number of fragments of Inca bones in neurocranium of human skulls from Central India. The knowledge of this variable is useful for neurosurgeons, anthropologists and radiologists.

  14. PERIPHERY/CORE RELATIONS IN THE INCA EMPIRE CARROTS AND STICKS IN AN ANDEAN WORLD SYSTEM

    Directory of Open Access Journals (Sweden)

    Lawrence A. Kuznar

    2015-08-01

    Full Text Available The Inca Empire exhibited labor exploitation and the rational extraction of resources from peripheral polities by a core polity. These characteristics fit the general definition of a world empire, although core/periphery relations were diverse. The nature of core/periphery relations depended on several attributes of the conquered polity including population size, political power, natural resources, and distance from the Inca core at Cuzco. A dynamic picture of core/periphery relations emerges as the outcome of Inca demands for labor and raw materials, and peripheral peoples' desire for control over their autonomy while seeking benefits from the Inca state.

  15. Cassini data assessment report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-08-01

    On October 15, 1997, the Cassini spacecraft was launched from Cape Canaveral Air Station (CCAS) and is now on its way to the planet Saturn. The functional support provided to NASA by DOE included the Advance Launch Support Group (ALSG). If there had been a launch anomaly, the ALSG would have provided a level of radiological emergency response support adequate to transition into a Federal Radiological Monitoring and Assessment Center (FRMAC). Additional functional radiological emergency response support, as part of the ALSG, included the: (1) Aerial Measurement System (AMS); (2) Atmospheric Release Advisory Capability (ARAC); (3) Geographic Information System (GIS); (4) Emergency Response Data System (ERDS); (5) Radiation Emergency Assistance Center and Training Site (REAC/TS); (6) Field monitoring and sampling; (7) Radioanalysis via RASCAL; (8) Source recovery; and (9) Neutron dosimetry and communications support. This functional support provided the capability to rapidly measure and assess radiological impacts from a launch anomaly. The Radiological Control Officer (RCO) on KSC established a Radiological Control Center (RADCC) as the focal point for all on-site and off-site radiological data and information flow. Scientists and radiological response personnel located at the RADCC managed the field monitoring team on the KSC/CCAS federal properties. Off-site radiological emergency response activities for all public lands surrounding the KSC/CCAS complex were coordinated through the Off-site ALSG located at the National Guard Armory in Cocoa, Florida. All of the in situ measurement data of good quality gathered during the dry run, the first launch attempt and the launch day are listed in this document. The RASCAL analysis results of the air filters and impactor planchets are listed.

  16. Saturn from Cassini-Huygens

    CERN Document Server

    Dougherty, Michele K; Krimigis, Stamatios M

    2009-01-01

    This book reviews our current knowledge of Saturn featuring the latest results obtained by the Cassini-Huygens mission. A global author team addresses the planet’s origin and evolution, internal structure, composition and chemistry, the atmosphere and ionosphere, the magnetosphere, as well as its ring system. Furthermore, Saturn's icy satellites are discussed. The book closes with an outlook beyond the Cassini-Huygens mission. Colorfully illustrated, this book will serve as a reference to researchers as well as an introduction for students.

  17. Imaging the interaction of the heliosphere with the interstellar medium from Saturn with Cassini.

    Science.gov (United States)

    Krimigis, S M; Mitchell, D G; Roelof, E C; Hsieh, K C; McComas, D J

    2009-11-13

    We report an all-sky image of energetic neutral atoms (ENAs) >6 kilo-electron volts produced by energetic protons occupying the region (heliosheath) between the boundary of the extended solar atmosphere and the local interstellar medium (LISM). The map obtained by the Ion and Neutral Camera (INCA) onboard Cassini reveals a broad belt of energetic protons whose nonthermal pressure is comparable to that of the local interstellar magnetic field. The belt, centered at approximately 260 degrees ecliptic longitude extending from north to south and looping back through approximately 80 degrees, appears to be ordered by the local interstellar magnetic field. The shape revealed by the ENA image does not conform to current models, wherein the heliosphere resembles a cometlike figure aligned in the direction of Sun's travel through the LISM.

  18. Enceladus Plume Density Modeling and Reconstruction for Cassini Attitude Control System

    Science.gov (United States)

    Sarani, Siamak

    2010-01-01

    In 2005, Cassini detected jets composed mostly of water, spouting from a set of nearly parallel rifts in the crust of Enceladus, an icy moon of Saturn. During an Enceladus flyby, either reaction wheels or attitude control thrusters on the Cassini spacecraft are used to overcome the external torque imparted on Cassini due to Enceladus plume or jets, as well as to slew the spacecraft in order to meet the pointing needs of the on-board science instruments. If the estimated imparted torque is larger than it can be controlled by the reaction wheel control system, thrusters are used to control the spacecraft. Having an engineering model that can predict and simulate the external torque imparted on Cassini spacecraft due to the plume density during all projected low-altitude Enceladus flybys is important. Equally important is being able to reconstruct the plume density after each flyby in order to calibrate the model. This paper describes an engineering model of the Enceladus plume density, as a function of the flyby altitude, developed for the Cassini Attitude and Articulation Control Subsystem, and novel methodologies that use guidance, navigation, and control data to estimate the external torque imparted on the spacecraft due to the Enceladus plume and jets. The plume density is determined accordingly. The methodologies described have already been used to reconstruct the plume density for three low-altitude Enceladus flybys of Cassini in 2008 and will continue to be used on all remaining low-altitude Enceladus flybys in Cassini's extended missions.

  19. Enceladus Plume Density Modeling and Reconstruction for Cassini Attitude Control System

    Science.gov (United States)

    Sarani, Siamak

    2010-01-01

    In 2005, Cassini detected jets composed mostly of water, spouting from a set of nearly parallel rifts in the crust of Enceladus, an icy moon of Saturn. During an Enceladus flyby, either reaction wheels or attitude control thrusters on the Cassini spacecraft are used to overcome the external torque imparted on Cassini due to Enceladus plume or jets, as well as to slew the spacecraft in order to meet the pointing needs of the on-board science instruments. If the estimated imparted torque is larger than it can be controlled by the reaction wheel control system, thrusters are used to control the spacecraft. Having an engineering model that can predict and simulate the external torque imparted on Cassini spacecraft due to the plume density during all projected low-altitude Enceladus flybys is important. Equally important is being able to reconstruct the plume density after each flyby in order to calibrate the model. This paper describes an engineering model of the Enceladus plume density, as a function of the flyby altitude, developed for the Cassini Attitude and Articulation Control Subsystem, and novel methodologies that use guidance, navigation, and control data to estimate the external torque imparted on the spacecraft due to the Enceladus plume and jets. The plume density is determined accordingly. The methodologies described have already been used to reconstruct the plume density for three low-altitude Enceladus flybys of Cassini in 2008 and will continue to be used on all remaining low-altitude Enceladus flybys in Cassini's extended missions.

  20. Inca: a novel p21-activated kinase-associated protein required for cranial neural crest development.

    Science.gov (United States)

    Luo, Ting; Xu, Yanhua; Hoffman, Trevor L; Zhang, Tailin; Schilling, Thomas; Sargent, Thomas D

    2007-04-01

    Inca (induced in neural crest by AP2) is a novel protein discovered in a microarray screen for genes that are upregulated in Xenopus embryos by the transcriptional activator protein Tfap2a. It has no significant similarity to any known protein, but is conserved among vertebrates. In Xenopus, zebrafish and mouse embryos, Inca is expressed predominantly in the premigratory and migrating neural crest (NC). Knockdown experiments in frog and fish using antisense morpholinos reveal essential functions for Inca in a subset of NC cells that form craniofacial cartilage. Cells lacking Inca migrate successfully but fail to condense into skeletal primordia. Overexpression of Inca disrupts cortical actin and prevents formation of actin "purse strings", which are required for wound healing in Xenopus embryos. We show that Inca physically interacts with p21-activated kinase 5 (PAK5), a known regulator of the actin cytoskeleton that is co-expressed with Inca in embryonic ectoderm, including in the NC. These results suggest that Inca and PAK5 cooperate in restructuring cytoskeletal organization and in the regulation of cell adhesion in the early embryo and in NC cells during craniofacial development.

  1. Properties of the Plasma Surrounding the Global Heliosphere Determined with Voyager 1&2 ions and ENA/INCA Observations at E > 5 keV

    Science.gov (United States)

    Krimigis, S. M.; Dialynas, K.; Mitchell, D. G.; Decker, R. B.; Roelof, E. C.

    2016-12-01

    The basic goal of the proposed Interstellar Mapping and Acceleration Probe (IMAP) is detailed scientific understanding of the Heliosheath (HS) and beyond, a region of space explored in situ by Voyager 1 (V1) since 2004, Voyager 2 (V2) since 2007, and remotely via energetic neutral atoms (ENA) by the Cassini/INCA (5.2-55 keV) since 2003 and IBEX (0.3-6 keV) since 2009. The partial overlap in energies (28 5 keV, the rest residing below that range, resulting in a beta (particle/magnetic pressure) always > 1, typically >10. (2) Based on the ENA-derived hot ion pressures, the interstellar magnetic field (ISMF) was predicted to be more than twice that expected in the literature i.e. similar to what was measured by V1 after crossing the heliopause (B 0.5 nT). (3) The width of the HS in the direction of V1 is 30 AU (predicted by INCA before the V1 HP crossing), but is thought to be larger (40-70 AU) in the southern ecliptic where V2, now 30 AU into the HS, currently travels. We address here the key question of the source of 5-55 keV ENAs that INCA measures. The analysis of INCA all-sky maps from 2003 to 2014 show that the decrease and recovery of ENA in the global heliosphere during this period (declining phase of SC23 and rise of SC24) is similar to that of the ions at V1/V2, consistent with the HS ions being the source of ENA. The close correspondence between ENA and ion spectra (despite the 140 AU distance between V1 and V2) as well as the similarity of ENA spectra over the nose and anti-nose directions, together with the recent V1 measurement of a BISMF 0.5nT, suggest that the global distributions of >5 keV ions in the heliosheath resembles a diamagnetic bubble with no significant tail-like feature (the alternative Parker 1961 model), also consistent with some recent MHD simulations and models.

  2. Political-Philosophical Perspectives about the Notions of Indian, Inca, and Mestizo on the «Comentarios reales de los Incas»

    Directory of Open Access Journals (Sweden)

    Alejandro Javier Viveros Espinosa

    2016-11-01

    Full Text Available This essay posits certain political-philosophical perspectives on the Inca Garcilaso de la Vega’s Primera parte de los Comentarios reales de los Incas (1609. To this purpose we will develop two hermeneutical movements. The first refers to a theoretical and methodological questioning related to the notion of Indian as a discursive construction during colonial times in the Andes area. The second deploys a critical exercise grounded on the interaction between the notions of Indian, Inca, and Mestizo, which is focused on how they build alternative subjectivities. Both movements consolidate an interpretation about the Inca Garcilaso’s political-philosophical reflections, remarking his proposals of a bifurcated modern civilizational project in the New World.

  3. Human antibody and antigen response to IncA antibody of Chlamydia trachomatis.

    Science.gov (United States)

    Tsai, P Y; Hsu, M C; Huang, C T; Li, S Y

    2007-01-01

    The high prevalence of C. trachomatis worldwide has underscored the importance of identifying specific immunogenic antigens in facilitating diagnosis as well as vaccine development. The aim of this study is to evaluate IncA antibody and antigen production in natural human infections. Our temporal expression study showed that IncA transcription and protein expression could be detected as early as 4 hours after the start of infection. Antibody responses could be detected in urine and genital swab samples from C. trachomatis-positive patients. It is especially interesting to note that the IncA antigen could be detected in urine. In conclusion, we have identified IncA as an important antigen in human. The potential applicability of the IncA antibody or antigen in the diagnosis as well as to vaccine development for C. trachomatis is also discussed.

  4. Watch Cassini-Huygens setting off for Saturn and Titan

    Science.gov (United States)

    1997-10-01

    NASA's Cassini spacecraft, to which the Italian Space Agency ASI has made an important contribution, is crammed with instruments prepared by American and European scientists. It will spend four busy years in orbit around Saturn, and explore its famous rings and eighteen known moons. On its arrival at Saturn in 2004, the Cassini orbiter will release the European Space Agency's probe Huygens towards the largest moon, Titan.Also equipped by multinational scientific teams, Huygens will parachute through Titan's atmosphere to accomplish the most distant landing ever made, on the surface of another world. Television coverage of the launch for viewers in Europe On Monday 13 October the launch window for Cassini-Huygens opens at 4.55 a.m. Florida time (EDT). Starting at 4.00 a.m. Florida time (10.00 a.m. in most of western Europe and 9.00 a.m. in Great Britain and Ireland) ESA will provide a live TV transmission via satellite for European news organizations and other organizations wishing to receive it. Views of the launch will be accompanied by interviews with scientists and engineers of the Cassini-Huygens joint mission. A short news package will be transmitted near the end of transmission, and details will be announced on air. If the launch occurs promptly, ESA's TV operation will last until about 60 minutes after launch (i.e. about noon, European time). Technical details for TV reception Two satellites links are available, both carrying English on audio channel 1 and French on audio channel 2. Broadcasters and others with digital receivers will favour Intelsat K, while those with analogue receivers can use Eutelsat 2. Full information on transponders etc. is contained in an appendix to this press release. Paris press centre At ESA Headquarters in Paris, journalists will be able to view the TV transmission and to obtain news and background information about the Cassini-Huygens mission. The press centre will open at 10.00 a.m. on 13 October. If you wish to attend, please

  5. Skeletal evidence for Inca warfare from the Cuzco region of Peru.

    Science.gov (United States)

    Andrushko, Valerie A; Torres, Elva C

    2011-11-01

    This article addresses the bioarchaeological evidence for Inca warfare through an analysis of 454 adult skeletons from 11 sites in the Inca capital region of Cuzco, Peru. These 11 sites span almost 1000 years (AD 600-1532), which allows for a comparison of the evidence for warfare before the Inca came to power (Middle Horizon AD 600-1000), during the time of Inca ascendency in the Late Intermediate Period (AD 1000-1400), and after the Inca came to power and expanded throughout the Cuzco region and beyond (Inca Imperial Period, AD 1400-1532). The results indicate that 100 of 454 adults (22.0%) showed evidence of cranial trauma. Of these, 23 individuals had major cranial injuries suggestive of warfare, consisting of large, complete, and/or perimortem fractures. There was scant evidence for major injuries during the Middle Horizon (2.8%, 1/36) and Late Intermediate Period (2.5%, 5/199), suggesting that warfare was not prevalent in the Cuzco region before and during the Inca rise to power. Only in the Inca Imperial Period was there a significant rise in major injuries suggestive of warfare (7.8%, 17/219). Despite the significant increase in Inca times, the evidence for major cranial injuries was only sporadically distributed at Cuzco periphery sites and was entirely absent at Cuzco core sites. These findings suggest that while the Inca used warfare as a mechanism for expansion in the Cuzco region, it was only one part of a complex expansion strategy that included economic, political, and ideological means to gain and maintain control. Copyright © 2011 Wiley-Liss, Inc.

  6. Structural mode significance using INCA. [Interactive Controls Analysis computer program

    Science.gov (United States)

    Bauer, Frank H.; Downing, John P.; Thorpe, Christopher J.

    1990-01-01

    Structural finite element models are often too large to be used in the design and analysis of control systems. Model reduction techniques must be applied to reduce the structural model to manageable size. In the past, engineers either performed the model order reduction by hand or used distinct computer programs to retrieve the data, to perform the significance analysis and to reduce the order of the model. To expedite this process, the latest version of INCA has been expanded to include an interactive graphical structural mode significance and model order reduction capability.

  7. Structural mode significance using INCA. [Interactive Controls Analysis computer program

    Science.gov (United States)

    Bauer, Frank H.; Downing, John P.; Thorpe, Christopher J.

    1990-01-01

    Structural finite element models are often too large to be used in the design and analysis of control systems. Model reduction techniques must be applied to reduce the structural model to manageable size. In the past, engineers either performed the model order reduction by hand or used distinct computer programs to retrieve the data, to perform the significance analysis and to reduce the order of the model. To expedite this process, the latest version of INCA has been expanded to include an interactive graphical structural mode significance and model order reduction capability.

  8. Cusco - La traza urbana de la Ciudad Inca

    OpenAIRE

    Agurto Calvo, Santiago

    1980-01-01

    La intención fundamental de esta publicación es dar a conocer, aunque sea en forma somera, los resultados de la investigación realizada para registrar los restos arqueológicos de superficie de la Ciudad del Cusco, por encargo del Proyecto PER-71/539, de UNESCO y el Gobierno Peruano. Dicha información se ha complementado con una hipótesis de reconstrucción del trazado urbano del Cusco Inca Imperial, la misma que se publica a manera de interpretación de los datos aportados por la investigaci...

  9. Reconstruyendo el itinerario del camino Inca Cajatambo: Pumpu a través del registro arqueológico

    OpenAIRE

    Casaverde Ríos, Guido

    2013-01-01

    El camino Inca investigado pertenece al Sistema Vial Inca de la sierra central, el cual era parte del ramal que se desprendía muy cerca del sitio Inca de Huamachuco por el norte y recorría por todo el Callejón de Huaylas, se dirigía a las localidades de Mangas, Copa, Puquián, Cajatambo, Oyón hasta Pumpu por el sur. Aquel tramo iba de forma paralela al tramo de camino Inca que unía los asentamientos Inca de Huamachuco, Callejón de Conchucos, Huánuco Pampa y Pumpu.

  10. CASSIUS: The Cassini Uplink Scheduler

    Science.gov (United States)

    Bellinger, Earl

    2012-01-01

    The Cassini Uplink Scheduler (CASSIUS) is cross-platform software used to generate a radiation sequence plan for commands being sent to the Cassini spacecraft. Because signals must travel through varying amounts of Earth's atmosphere, several different modes of constant telemetry rates have been devised. These modes guarantee that the spacecraft and the Deep Space Network agree with respect to the data transmission rate. However, the memory readout of a command will be lost if it occurs on a telemetry mode boundary. Given a list of spacecraft message files as well as the available telemetry modes, CASSIUS can find an uplink sequence that ensures safe transmission of each file. In addition, it can predict when the two on-board solid state recorders will swap. CASSIUS prevents data corruption by making sure that commands are not planned for memory readout during telemetry rate changes or a solid state recorder swap.

  11. Ongoing Analysis of Jupiter's Equatorial Hotspots and Plumes from Cassini

    Science.gov (United States)

    Choi, D. S.; Showmwn, A. P.; Vasavada, A. R.; Simon-Miller, A. A.

    2012-01-01

    We present updated results from our ongoing analysis of Cassini observations of Jupiter's equatorial meteorology. For two months preceding the spacecraft's closest approach of the planet, the ISS instrument onboard Cassini regularly imaged the atmosphere of Jupiter. We created time-lapse movies from this period that show the complex activity and interactions of the equatorial atmosphere. During this period, hot spots exhibited significant variations in size and shape over timescales of days and weeks. Some of these changes appear to be a result of interactions with passing vortex systems in adjacent latitudes. Strong anticyclonic gyres to the southeast of the dark areas converge with flow from the west and appear to circulate into a hot spot at its southwestern corner.

  12. The rotational dynamics of Titan from Cassini RADAR images

    Science.gov (United States)

    Meriggiola, Rachele; Iess, Luciano; Stiles, Bryan. W.; Lunine, Jonathan. I.; Mitri, Giuseppe

    2016-09-01

    Between 2004 and 2009 the RADAR instrument of the Cassini mission provided 31 SAR images of Titan. We tracked the position of 160 surface landmarks as a function of time in order to monitor the rotational dynamics of Titan. We generated and processed RADAR observables using a least squares fit to determine the updated values of the rotational parameters. We provide a new rotational model of Titan, which includes updated values for spin pole location, spin rate, precession and nutation terms. The estimated pole location is compatible with the occupancy of a Cassini state 1. We found a synchronous value of the spin rate (22.57693 deg/day), compatible at a 3-σ level with IAU predictions. The estimated obliquity is equal to 0.31°, incompatible with the assumption of a rigid body with fully-damped pole and a moment of inertia factor of 0.34, as determined by gravity measurements.

  13. Inhibitor of CDK interacting with cyclin A1 (INCA1) regulates proliferation and is repressed by oncogenic signaling

    DEFF Research Database (Denmark)

    Baumer, Nicole; Tickenbrock, Lara; Tschanter, Petra

    2011-01-01

    The cell cycle is driven by the kinase activity of cyclin/CDK complexes which is negatively regulated by CDK inhibitor proteins. Recently, we identified INCA1 as interaction partner and substrate of cyclin A1 in complex with CDK2. On a functional level, we identified a novel cyclin binding site...... in the INCA1 protein. INCA1 inhibited CDK2 activity and cell proliferation. The inihibitory effects depended on the cyclin-interacting domain. Mitogenic and oncogenic signals suppressed INCA1 expression, while it was induced by cell cycle arrest. We established a deletional mouse model that showed increased...... CDK2 activity in spleen with altered spleen architecture in Inca1-/- mice. Inca1-/- embryonic fibroblasts showed an increase in the fraction of S-phase cells. Furthermore, blasts from ALL and AML patients expressed significantly reduced INCA1 levels highlighting its relevance for growth control...

  14. INCA, a novel human caspase recruitment domain protein that inhibits interleukin-1beta generation.

    Science.gov (United States)

    Lamkanfi, Mohamed; Denecker, Geertrui; Kalai, Michael; D'hondt, Kathleen; Meeus, Ann; Declercq, Wim; Saelens, Xavier; Vandenabeele, Peter

    2004-12-10

    Using in silico methods for screening the human genome for new caspase recruitment domain (CARD) proteins, we have identified INCA (Inhibitory CARD) as a protein that shares 81% identity with the prodomain of caspase-1. The INCA gene is located on chromosome 11q22 between the genes of COP/Pseudo-ICE and ICEBERG, two other CARD proteins that arose from caspase-1 gene duplications. We show that INCA mRNA is expressed in many tissues. INCA is specifically upregulated by interferon-gamma in the monocytic cell lines THP-1 and U937. INCA physically interacts with procaspase-1 and blocks the release of mature IL-1beta from LPS-stimulated macrophages. Unlike COP/Pseudo-ICE and procaspase-1, INCA does not interact with RIP2 and does not induce NF-kappaB activation. Our data show that INCA is a novel intracellular regulator of procaspase-1 activation, involved in the regulation of pro-IL-1beta processing and its release during inflammation.

  15. Maintenance of leukemia-initiating cells is regulated by the CDK inhibitor Inca1.

    Directory of Open Access Journals (Sweden)

    Nicole Bäumer

    Full Text Available Functional differences between healthy progenitor and cancer initiating cells may provide unique opportunities for targeted therapy approaches. Hematopoietic stem cells are tightly controlled by a network of CDK inhibitors that govern proliferation and prevent stem cell exhaustion. Loss of Inca1 led to an increased number of short-term hematopoietic stem cells in older mice, but Inca1 seems largely dispensable for normal hematopoiesis. On the other hand, Inca1-deficiency enhanced cell cycling upon cytotoxic stress and accelerated bone marrow exhaustion. Moreover, AML1-ETO9a-induced proliferation was not sustained in Inca1-deficient cells in vivo. As a consequence, leukemia induction and leukemia maintenance were severely impaired in Inca1-/- bone marrow cells. The re-initiation of leukemia was also significantly inhibited in absence of Inca1-/- in MLL-AF9- and c-myc/BCL2-positive leukemia mouse models. These findings indicate distinct functional properties of Inca1 in normal hematopoietic cells compared to leukemia initiating cells. Such functional differences might be used to design specific therapy approaches in leukemia.

  16. Adding "Missed" Science to Cassini's Ops Plan

    Science.gov (United States)

    Roy, Mou; Burton, Marcia E.; Edgington, Scott; Pitesky, Jo E.; Steadman, Kimberly B.; Ray, Trina L.; Evans, Mike

    2014-01-01

    The phenomenal success of the Cassini Mission at Saturn is largely due to flagship instruments, in a target rich environment, for a long period of time, executing almost error free complex mission operations. A smooth transition from cruise operations through the prime science mission and extended science (Equinox) mission culminating in the currently executing Solstice mission has folded in necessary procedural alterations due to improved understanding of the spacecraft, instruments, uplink and planning systems as well as additional science objectives. These have come with the maturation of the mission along with management of workforce reductions. One important set of operational changes has been initiated due to scientific findings highlighting "missed" science opportunities. This is the case for the Titan Meteorology Campaigns and Saturn Storm Watch Campaigns. These observations involve long term monitoring of the atmospheres of Titan and Saturn while the spacecraft and science teams are focused on other high priority targets of opportunity (like Enceladus). Our objective in this paper is to emphasize how a non-invasive strategy to get additional remarkable science was conceived and implemented in a mission with an already well defined operational plan. To illustrate this we will detail Titan Meteorology Campaign and Saturn Storm Watch Campaign integration and implementation strategies as well as the scientific goals and achievements of both.

  17. A Change Of Seasons On Titan Observed By Cassini

    Science.gov (United States)

    Teanby, Nicholas; Irwin, P.; Nixon, C.; de Kok, R.; Vinatier, S.; Coustenis, A.; Sefton-Nash, E.; Calcutt, S.; Flasar, M.

    2012-10-01

    Cassini's tour of the Saturn system now spans over eight years, equivalent to more than a quarter of a Titan year. This provides us with an excellent opportunity to study atmospheric seasonal behaviour. Here we use infrared spectra measured by Cassini's CIRS instrument to determine variations in temperature and composition throughout the mission - covering northern fall to northern spring - and use these quantities as tracers to probe changes in atmospheric circulation. Our results focus on the middle atmosphere (stratosphere-mesosphere at 100-500km altitude), where the majority of atmospheric super-rotation occurs and where high altitude photochemical production is linked to the lower atmosphere and surface. Our observations show significant changes in the distribution of trace chemical species with season - indicating changes in large-scale circulation patterns around the 2009 equinox. The timing and behaviour of the transition between different seasonal regimes will be discussed, in addition to implications for atmospheric general circulation models. Cassini has allowed us to study these phenomenon for the first time and is providing fresh insight into planetary atmospheric processes.

  18. Abundances of Jupiter's Trace Hydrocarbons from Voyager and Cassini

    Science.gov (United States)

    Nixon, C. A.; Achterberg, R. K.; Romani, P. N.; Allen, M.; Zhang, X.; Teanby, N. A.; Irwin, P. G. J.; Flasar, F. M.

    2010-01-01

    The flybys of Jupiter by the Voyager spacecraft in 1979, and over two decades later by Cassini in 2000, have provided us with unique datasets from two different epochs, allowing the investigation of seasonal change in the atmosphere. In this paper we model zonal averages of thermal infrared spectra from the two instruments, Voyager 1 IRIS and Cassini CIRS, to retrieve the vertical and meridional profiles of temperature, and the abundances of the two minor hydrocarbons, acetylene (C2H2) and ethane (C2H6). The spatial variation of these gases is controlled by both chemistry and dynamics, and therefore their observed distribution gives us an insight into both processes, We find that the two gases paint quite different pictures of seasonal change. Whilst the 2-D cross-section of C2H6 abundance is slightly increased and more symmetric in 2000 (northern summer solstice) compared to 1979 (northern fall equinox), the major trend of equator to pole increase remains. For C2H2 on tile other hand, the Voyager epoch exhibits almost no latitudinal variation, whilst the Cassini era shows a marked decrease polewards in both hemispheres. At the present time, these experimental findings are in advance of interpretation, as there are no published models of 2-D Jovian seasonal chemical variation available for comparison.

  19. Abundances of Jupiter's Trace Hydrocarbons from Voyager and Cassini

    Science.gov (United States)

    Nixon, C. A.; Achterberg, R. K.; Romani, P. N.; Allen, M.; Zhang, X.; Teanby, N. A.; Irwin, P. G. J.; Flasar, F. M.

    2010-01-01

    The flybys of Jupiter by the Voyager spacecraft in 1979, and over two decades later by Cassini in 2000, have provided us with unique datasets from two different epochs, allowing the investigation of seasonal change in the atmosphere. In this paper we model zonal averages of thermal infrared spectra from the two instruments, Voyager 1 IRIS and Cassini CIRS, to retrieve the vertical and meridional profiles of temperature, and the abundances of the two minor hydrocarbons, acetylene (C2H2) and ethane (C2H6). The spatial variation of these gases is controlled by both chemistry and dynamics, and therefore their observed distribution gives us an insight into both processes, We find that the two gases paint quite different pictures of seasonal change. Whilst the 2-D cross-section of C2H6 abundance is slightly increased and more symmetric in 2000 (northern summer solstice) compared to 1979 (northern fall equinox), the major trend of equator to pole increase remains. For C2H2 on tile other hand, the Voyager epoch exhibits almost no latitudinal variation, whilst the Cassini era shows a marked decrease polewards in both hemispheres. At the present time, these experimental findings are in advance of interpretation, as there are no published models of 2-D Jovian seasonal chemical variation available for comparison.

  20. Rpws Science Today and in Cassini's Final Three Year

    Science.gov (United States)

    Kurth, W. S.; Lamy, L.

    2014-12-01

    Ten years of Cassini/RPWS remote and in situ observations of Saturn and its environment have provided a rich return feeding numerous studies of the various types of kronian radio emissions (such as Saturn's kilometric radiation [SKR], auroral hiss, narrowband [NB] and drifting burst emissions, and Saturn's electrostatic discharges [SED]), local plasma waves (such as chorus, upper hybrid bands and electron cyclotron harmonic emissions) and dusty plasmas. Nonetheless, several major objectives for RPWS science remain for the last three years of the Cassini mission, and will culminate with the detailed study of Saturn's auroral regions, where SKR and possibly other types of radio waves are produced and large-scale plasma acceleration is suspected to take place. During the F-ring and proximal orbital sequences, Cassini is expected to pass through northern and southern auroral regions tens of times around noon local time. These passes can be accurately predicted through the modeling of SKR sources and in turn help to trigger combined observations with other Cassini instruments and Earth-based observatories such as Hubble. Altogether, these observations will provide crucial complementary insights to understand kronian auroral processes. RPWS will also continue to measure the rotational modulation of various radio emissions (SKR, NB and hiss), pushing forward the study of magnetospheric periodicities long after equinox, pursue the monitoring of SEDs and lightning whistlers, whose occurrence probes the activity of atmospheric storms, or probe in detail the dusty environment of the D ring and wave-particle interactions taking place in the very inner magnetosphere where the magnetic field links the planet to the rings.

  1. O inca pano: mito, história e modelos etnológicos

    Directory of Open Access Journals (Sweden)

    Oscar Calavia Sáez

    2000-10-01

    Full Text Available Os mitos relativos ao Inca recolhidos na Amazônia entre vários grupos de língua pano têm sido entendidos como memórias de um passado remoto regido por uma aristocracia quechua ou como expressão de uma estrutura identitária ou cosmológica em que o Inca significaria o Branco ou uma alteridade celestial. Tais interpretações, apesar de seu valor heurístico, limitam nossa compreensão dos aspectos estruturais e históricos do Inca Pano. Propõe-se aqui entender o Inca também como um símbolo eficiente, vinculado a modelos sociológicos e/ou artísticos de alto valor distintivo: povos como os Shipibo-Conibo e os Kaxinawá cristalizam em torno dessa figura uma tradição que os destaca do conjunto dos grupos nawa vizinhos.The Amazonian myths collected among certain Panoan-speaking peoples which make reference to the Inca figure have generally been subject to one of two interpretations. They are either seen to recall a remote past in which these peoples may have been ruled by Quechua aristocrats or they are seen to be structural aspects of identity or cosmology, in which the Inca would be representative of the White man or of some celestial alterity. These interpretations, in spite of their heuristic value, serve to limit our understanding of structural and historical aspects of the Pano Inca. This article proposes that we also try to understand the Pano Inca as an effective symbol, related to social and/or artistic models with their own distinctive values: people such as the Shipibo-Conibo and the Kaxinawa have shaped around this figure a tradition which sets them apart from the neighbouring Nawa groups.

  2. The Inca healer: empirical medical knowledge and magic in pre-Columbian Peru

    OpenAIRE

    Elferink, Jan G R

    2015-01-01

    The role of medical practitioners among the Incas is addressed, based on archeological findings and especially the writings of the Spanish chroniclers. In Inca medicine a large role was reserved for religion and magic but at the same time an extensive knowledge of medicinal plants was available. As a consequence there were several types of healers who cured with a mixture of medicinal plants and religious-magic ceremonies. The hampicamayoc or ‘official in charge of medicines’ was the one who ...

  3. Chlamydial development is blocked in host cells transfected with Chlamydophila caviae incA.

    Science.gov (United States)

    Alzhanov, Damir; Barnes, Jennifer; Hruby, Dennis E; Rockey, Daniel D

    2004-07-01

    Chlamydiae produce a set of proteins, termed Inc proteins, that are localized to the inclusion membrane and exposed to the host cell cytosol. Little information exists regarding the interaction of Inc proteins with the eukaryotic cell. To examine these interactions, Vaccinia virus vectors and mammalian plasmid-based systems were used to express inc genes in mammalian cells. Cells transfected with plasmids expressing Chlamydophila caviae incA were not productively infected by C. caviae. Expression of C. caviae incA also reduced inclusion formation by Chlamydia trachomatis, but not to the degree seen for C. caviae. Chlamydia trachomatis incA did not block development of either C. trachomatis or C. caviae. Deletion mutagenesis was used to demonstrate that plasmids encoding either the amino or carboxy-terminal regions of the protein, as well as the changing of a single amino acid within IncA (serine 17) could not block C. caviae infection. Immunoblot analysis of truncated IncA in a Vaccinia virus system provided evidence that serine 17 of C. caviae IncA is a target for phosphorylation. These experiments provide insight into the interaction of Inc proteins with the host cell and introduce a model system where these interactions can be explored further.

  4. Chlamydial development is blocked in host cells transfected with Chlamydophila caviae incA

    Directory of Open Access Journals (Sweden)

    Barnes Jennifer

    2004-07-01

    Full Text Available Abstract Background Chlamydiae produce a set of proteins, termed Inc proteins, that are localized to the inclusion membrane and exposed to the host cell cytosol. Little information exists regarding the interaction of Inc proteins with the eukaryotic cell. To examine these interactions, Vaccinia virus vectors and mammalian plasmid-based systems were used to express inc genes in mammalian cells. Results Cells transfected with plasmids expressing Chlamydophila caviae incA were not productively infected by C. caviae. Expression of C. caviae incA also reduced inclusion formation by Chlamydia trachomatis, but not to the degree seen for C. caviae. Chlamydia trachomatis incA did not block development of either C. trachomatis or C. caviae. Deletion mutagenesis was used to demonstrate that plasmids encoding either the amino or carboxy-terminal regions of the protein, as well as the changing of a single amino acid within IncA (serine 17 could not block C. caviae infection. Immunoblot analysis of truncated IncA in a Vaccinia virus system provided evidence that serine 17 of C. caviae IncA is a target for phosphorylation. Conclusions These experiments provide insight into the interaction of Inc proteins with the host cell and introduce a model system where these interactions can be explored further.

  5. Cassini observation of Jovian anomalous continuum radiation

    Science.gov (United States)

    Ye, Sheng-Yi; Gurnett, D. A.; Menietti, J. D.; Kurth, W. S.; Fischer, G.; Schippers, P.; Hospodarsky, G. B.

    2012-04-01

    Jovian anomalous continuum is a narrowband electromagnetic radiation near 10 kHz that can escape from Jupiter's magnetosphere to interplanetary space. One possible source mechanism is the magnetosheath re-radiation of the Jovian low frequency radio emissions such as the quasiperiodic (QP) radio emissions, broadband kilometric radiation (bKOM) and non-thermal continuum. Jovian anomalous continuum was consistently observed by the Cassini Radio and Plasma Wave Science instrument from 2000 to 2004, right before the Saturn orbit insertion, which means the radiation can be detected as far as 8 AU away from Jupiter. An analysis of intensity versus radial distance shows that the Jovian anomalous continuum has a line source rather than a point source, consistent with the theory that the emission is radiated by the whole length of the magnetotail. The emissions are modulated at the system III period of Jupiter and are unpolarized. Since the lower cutoff frequency of the anomalous continuum is related to the plasma frequency in the magnetosheath of Jupiter, which is a function of solar wind density, the recurrent variations of the lower cutoff frequency can be used as a remote diagnostic of the solar wind condition at Jupiter. We propose that the frequency dispersion, a unique characteristic of the anomalous continuum, is likely a comprehensive effect of both the slow group velocity near the local plasma frequency and the refraction/scattering of the waves by density structures as they propagate in the magnetosheath.

  6. The Italian involvement in Cassini radar

    Science.gov (United States)

    Nirchio, F.; Pernice, B.; Borgarelli, L.; Dionisio, C.

    1991-12-01

    The Radio Frequency Electronic Subsystem (RFES) of the Cassini radar is described. The requirements of the Cassini radar are summarized. The design parameters taken into consideration in developing the RFES are described. The RFES interfaces with the High Gain Antenna (HGA) for signal transmission and reception. The operational parameters of the Cassini radar are presented. The front end electronics (FEE), microwave receiver (MR), high power amplifier (HPA), frequency generator (FG), digital chip generator (DCG), Chirp Up Converter and Amplifier (CUCA) and power supply of the RFES are described.

  7. Tras las huella del silencio: Potosí, los incas y Toledo Por traz das pegadas do silencio: Potosí, os Incas e o Toledo Behind the Footprints of Silence: Potosí, the Incas and Toledo

    Directory of Open Access Journals (Sweden)

    Tristan Platt

    2010-12-01

    Full Text Available ¿Por qué los señores aymaras de Charcas y el Inca Paullo, después de entregar las minas de plata de Porco a Hernando Pizarro en 1538, guardaron silencio sobre Potosí (distante a unas pocas leguas, que no se descubrió hasta abril de 1545? Reuniendo un mosaico de datos aparentemente inconexos, este artículo revisa las versiones corrientes del descubrimiento del cerro e interroga un curioso silencio presente en las fuentes. Reconstruyendo una red previamente desconocida de incas y españoles, se propone que, más que el hallazgo providencial de un yanacona aislado (la versión recibida, Potosí se manifestó como continuación de la política de "obediencia" subyacente en la entrega de Porco, ahora dirigida por el rival del Inca Paullo: el Inca Manco refugiado en Vilcabamba. Esta política de Manco buscaba apoyar al Rey y las Nuevas Leyes (1542 en contra de la amenaza mayor representada por Gonzalo Pizarro y los encomenderos. El artículo comenta, asimismo, la promoción toledana de la "leyenda providencial", retomando en cambio la interpretación de Guaman Poma de la entrega de Potosí como una iniciativa de los incas, quienes lo habrían fundado bajo Inca Túpac Yupanqui. Esta versión concuerda con las últimas investigaciones geológicas y arqueológicas.Por que os senhores aymaras de Charcas e o Inca Paullo, depois de entregar as minas de prata de Porco a Hernando Pizarro em 1538, ficaram em silencio em relação ao Potosí (distante a umas poucas léguas que não foi descoberta até abril de 1545? Resumindo um mosaico de dados aparentemente sem conexão, este artigo revisa as versões correntes em relação à descoberta do morro e se questiona em relação ao curioso silêncio presente nas fontes. Reconstruindo uma rede antes desconhecida de incas e espanhóis, a proposta é que, mais que a descoberta providencial de um yanacona isolado (a versão recebida, Potosí manifestou-se como a continuação da política de "obedi

  8. El testimonio inca de la conquista del Perú

    Directory of Open Access Journals (Sweden)

    1978-01-01

    Full Text Available Ce témoignage de Cayo Inga est un document important qui retrace les succès des premières années de la pénétration espagnole au Pérou, de la côte de Tumbes à la ville de Cuzco. Sa valeur exceptionnelle tient à la qualité de l'informateur-membre du lignage inca et au fait qu'il ait été un témoin personnel des faits qu'il décrit. Par ce manuscrit, nous savons que Waskar Inga connut opportunément l'invasion étrangère à partir de la côte de Tumbes et que les Espagnols exigèrent une rançon au captif Atao Wallpa lui promettant de relâcher après. Nous sommes également renseignés sur le fameux pillage du temple de Pachacamac, sur la dramatique demande d'Atao Wallpa suppliant d'être exilé en Espagne et sur l'emprisonnement de Mango Inga Yupangui. Enfin, ce manuscrit éclaircit quelques faits quant aux sièges de la ville de Cuzco et de celle de Lima en 1536. El testimonio de Cayo Inga, es un documento excepcional para rehacer los sucesos de los primeros años de la penetración española en el Perú, de la costa tumbesina a la ciudad del Cuzco primero por la calidad del informante miembro del linaje Inca y segundo por su presencialidad en el lugar de los hechos. Este manuscrito, aclara que Waskar Inga conoció oportunamente la invasión de la costa tumbesina por los extranjeros y refiere que los españoles exigieron al cautivo Atao Wallpa un rescate, prometiéndole soltarlo después. Reseña a la vez el famoso saqueo del adoratorio de Pachacamac, el dramático pedido de Atao Wallpa para que lo exiliaran a España y el prendimiento de Mango Inga Yupangui, finalmente aporta datos sobre los asedios de la ciudad del Cuzco y de Lima en 1536. Cayo Inga's testimony is a document of exceptional value in the retracing of the events of the first years of the Spanish invasion and occupation of the country from Tumbes to Cuzco. It is remarkable for the quality of the source of information, since the reporter was both a member of the Inca

  9. CDA in-situ measurements during Cassini's F-ring plane crossings in 2017

    Science.gov (United States)

    Srama, Ralf; Moragas-Klostermeyer, Georg; Albin, Thomas; Economou, Thanasis; Hsu, Sean; Horanyi, Mihaly; Kempf, Sascha; Li, Yanwei; Postberg, Frank; Simolka, Jonas; Soja, Rachel; Strack, Heiko; Altobelli, Nicolas

    2017-04-01

    The Cosmic Dust Analyzer (CDA) onboard Cassini characterized successfully the dust environment at Saturn since 2004. The instrument measures the primary charge, speed, mass and composition of individual submicron and micron sized dust grains. Starting in December 2016 Cassini performed ring plane crossings at radial distances of 2.48 Saturn radii. For the first time, an in-situ dust detector explored this F-ring region of Saturn. CDA performed density, mass and compositional measurements. Furthermore, the High Rate Detector was activated using a high time and spatial resolution. The spatial resolution on January 2nd (2017) was as low as 2000 meters. Here, we do report preliminary results of the in-situ measurements of three F-ring orbit crossings. The relative encounter speed between Cassini and F-ring particles was approximately 20 km per second.

  10. INCA-CE: a Central European initiative in nowcasting severe weather and its applications

    Science.gov (United States)

    Kann, A.; Pistotnik, G.; Bica, B.

    2012-04-01

    The INCA-CE (Integrated Nowcasting through Comprehensive Analysis - Central Europe) project aims at implementing a transnational weather information system as well as applications for different socio-economic sectors to reduce risks of major economic damage and loss of life caused by severe weather. Civil protection and also stakeholders from economic sectors are in a growing need of accurate and reliable short-term weather forecasts. Within INCA-CE, a state-of-the art nowcasting system (INCA) is implemented at weather services throughout the European Union's CE (Central Europe) Programme Area, providing analyses and short term forecasts to the aforementioned end-users. In a coherent approach, the INCA (Integrated Nowcasting through Comprehensive Analysis) system will be adapted for implementation and use in a number of partner countries. Within transregional working groups, the gap between short-term weather information and its downstream activities in hydrological disaster management, civil protection and road management will be bridged and best practice management and measure plans will be produced. A web-based platform for outreach to related socio-economic sectors will initiate and foster a dialogue between weather services and further stakeholders like tourism or the insurance sector, flood authorities for disaster management, and the construction industry for cost-efficient scheduling and planning. Furthermore, the project will produce a compact guideline for policy makers on how to combine structural development aspects with these new features. In the present paper, an outline of the project implementation, a short overview about the INCA system and two case studies on precipitation nowcasts will be given. Moreover, directions for further developments both within the INCA system and the INCA-CE project will be pointed out.

  11. Cassini UVIS Auroral Observations in 2016

    Science.gov (United States)

    Pryor, Wayne R.; Jouchoux, Alain; Esposito, Larry W.; Radioti, Aikaterini; Grodent, Denis; Gustin, Jacques; Gerard, Jean-Claude; Lamy, Laurent; Badman, Sarah; Bunce, Emma; Cecconi, Baptiste; Clarke, John T.; Crary, Frank; Dougherty, Michele; Dyudina, Ulyana A.; Kurth, William; Mitchell, Don; Nichols, Jonathan; Prange, Renee; Schippers, Patricia; Zarka, Philippe; Cassini UVIS Team

    2016-10-01

    In June of 2016, the Cassini Saturn orbiter began a series of high inclination orbits that will continue until September 2017 when the mission ends as Cassini enters the Saturn atmosphere. These orbits present excellent views of Saturn's polar regions suitable for auroral imaging at the closest distances to date, with the additional prospect of simultaneous particle and fields measurements within the sources of Saturn Kilometric Radiation (SKR) associated with ultraviolet auroral emissions and/or acceleration regions likely coinciding with them. We will present new Cassini Ultraviolet Imaging Spectrograph (UVIS) auroral images, spectra and movies obtained during the summer and fall of 2016 and put them in the context of auroral data collected since Cassini orbit insertion in 2004. Included in the new data will be UVIS south polar observations obtained simultaneously with Hubble Space Telescope observations of the north polar region on June 29, 2016 and August 19, 2016.

  12. Cassini: Mission to Saturn and Titan

    Science.gov (United States)

    Kerridge, Stuart J.; Flury, Walter; Horn, Linda J.; Lebreton, Jean-Pierre; Stetson, Douglas S.; Stoller, Richard L.; Tan, Grace H.

    1992-01-01

    The Cassini Mission to Saturn and Titan represents an important step into the exploration of the outerplanets. It will expand on the flyby encounters of Pioneer and Voyager and parallel the detailed exploration of the Jupiter system to be accomplished by the Galileo Mission. By continuing the study of the two giant planets and enabling detailed comparisons of their structure and behavior, Cassini will provide a tremendous insight into the formation and evolution of the solar system. In addition, by virtue of its focus on the Saturnian satellite Titan, Cassini will return detailed data on an environment whose atmospheric chemistry may resemble that of the primitive Earth. The scientific objectives can be divided into five categories: Titan, Saturn, rings, icy satellites, and magnetospheres. The key area of interest to exobiologists is Titan; the other four scientific categories will be discussed briefly to provide a comprehensive overview of the Cassini Mission.

  13. Cassini's Scientist for a Day program

    Science.gov (United States)

    Seal, David

    2009-11-01

    NASA's Cassini project has conducted a series of innovative "Scientist for a Day" outreach sessions with great success. Individual students and classrooms are presented, via the Cassini web site, with a selection of images that could be taken by the Cassini spacecraft in orbit around Saturn. Student essays are submitted indicating their preferred image, along with a detailed description of why that image was selected, often drawing heavily from material found elsewhere in the Cassini web resources. Winners from different age categories are chosen, and the selected images are sequenced. Very soon after the images reach the ground, winning classrooms are invited to participate via tele- and video-con with key Cassini scientists and engineers, where interactive discussions take place. This program has been very successful and is considered a key outreach highlight of Cassini and JPL in general. It reaches a significant number of students, involves them directly in image planning, and engages them in a highly interactive and inspirational environment requiring detailed study and creative thought.

  14. EL INTÉRPRETE FELIPILLO ENTRE INCAS Y CONQUISTADORES

    Directory of Open Access Journals (Sweden)

    Jochen Plötz

    2016-01-01

    Full Text Available El artículo busca contribuir a la investigación de los papeles atribuidos al mediador lingüístico y, por extensión, transcultural, como son los de traidor, el que no dice todo lo que sabe persiguiendo intereses propios, y otros más. Se establecen unas pautas que caracterizan las situaciones comunicativas conflictivas a lo largo de la historia. Asimismo, se propone una línea de investigación traductológica, interesada en la realización de la mediación lingüística misma y sus circunstancias, como aporte a la historia de la traducción. El caso al que se aplica este programa en el presente artículo es el enfrentamiento entre los incas y los conquistadores europeos en el Perú, en el cual actuaron unos intérpretes indígenas sobre los que se ha producido y se sigue produciendo toda una gama de proyecciones y atribuciones.

  15. INCAS QUICK THERMAL TEST SHOCK INSTALLATION - QTS1

    Directory of Open Access Journals (Sweden)

    Constantin VILCU

    2009-12-01

    Full Text Available From the assembly of the wear factors which act on the “hot parts” of the turbo engines,respectively on the protective coatings, the thermal shock acts the most perturbing.The behavior of the materials at thermal shock is evaluated at present on unique installations,constructive and methodical different, in the specialized laboratories of the materialsmanufacturer, protective coatings included as well as of those specialized in testing.The thermal test shock installation conceived by INCAS and achieved in collaboration with INCDTCOMOTI for testing of the materials at thermal shock, especially those from the aerospatialdomain, represents a versatile construction, in progress in comparison with those known.The QTS1 - quick thermal test shock installation assures with reproducible results the materialevaluation in the heating and cooling speed conditions up to 100°C/s at heating and 60ºC/s atcooling, situations which correspond to the extreme functional conditions of the turbo engines,space shuttle, cogenerative systems, etc.

  16. incaRNAfbinv: a web server for the fragment-based design of RNA sequences.

    Science.gov (United States)

    Drory Retwitzer, Matan; Reinharz, Vladimir; Ponty, Yann; Waldispühl, Jérôme; Barash, Danny

    2016-07-08

    In recent years, new methods for computational RNA design have been developed and applied to various problems in synthetic biology and nanotechnology. Lately, there is considerable interest in incorporating essential biological information when solving the inverse RNA folding problem. Correspondingly, RNAfbinv aims at including biologically meaningful constraints and is the only program to-date that performs a fragment-based design of RNA sequences. In doing so it allows the design of sequences that do not necessarily exactly fold into the target, as long as the overall coarse-grained tree graph shape is preserved. Augmented by the weighted sampling algorithm of incaRNAtion, our web server called incaRNAfbinv implements the method devised in RNAfbinv and offers an interactive environment for the inverse folding of RNA using a fragment-based design approach. It takes as input: a target RNA secondary structure; optional sequence and motif constraints; optional target minimum free energy, neutrality and GC content. In addition to the design of synthetic regulatory sequences, it can be used as a pre-processing step for the detection of novel natural occurring RNAs. The two complementary methodologies RNAfbinv and incaRNAtion are merged together and fully implemented in our web server incaRNAfbinv, available at http://www.cs.bgu.ac.il/incaRNAfbinv.

  17. Establishing homology between mitochondrial calcium uniporters, prokaryotic magnesium channels and chlamydial IncA proteins.

    Science.gov (United States)

    Lee, Andre; Vastermark, Ake; Saier, Milton H

    2014-08-01

    Mitochondrial calcium uniporters (MCUs) (TC no. 1.A.77) are oligomeric channel proteins found in the mitochondrial inner membrane. MCUs have two well-conserved transmembrane segments (TMSs), connected by a linker, similar to bacterial MCU homologues. These proteins and chlamydial IncA proteins (of unknown function; TC no. 9.B.159) are homologous to prokaryotic Mg(2+) transporters, AtpI and AtpZ, based on comparison scores of up to 14.5 sds. A phylogenetic tree containing all of these proteins showed that the AtpZ proteins cluster coherently as a subset within the large and diverse AtpI cluster, which branches separately from the MCUs and IncAs, both of which cluster coherently. The MCUs and AtpZs share the same two TMS topology, but the AtpIs have four TMSs, and IncAs can have either two (most frequent) or four (less frequent) TMSs. Binary alignments, comparison scores and motif analyses showed that TMSs 1 and 2 align with TMSs 3 and 4 of the AtpIs, suggesting that the four TMS AtpI proteins arose via an intragenic duplication event. These findings establish an evolutionary link interconnecting eukaryotic and prokaryotic Ca(2+) and Mg(2+) transporters with chlamydial IncAs, and lead us to suggest that all members of the MCU superfamily, including IncAs, function as divalent cation channels. © 2014 The Authors.

  18. Preconquest Peruvian neurosurgeons: a study of Inca and pre-Columbian trephination and the art of medicine in ancient Peru.

    Science.gov (United States)

    Marino, R; Gonzales-Portillo, M

    2000-10-01

    Trephination and craniotomy performed by abrasion, scraping, crosscut sawing, and drilling are the oldest known surgical techniques used by primitive peoples. As a result of archaeological findings, the human skull is the most frequently studied part of the excavated body, leading to the creation of a new aspect of anthropology known as "cultural osteology." Found in ancient tombs, the human remains, mummies, skeletons, and their belongings, including war instruments, pottery, clothing, jewels, and surgical instruments, constitute the richest source of insight into the lives and pragmatic activities of ancient cultures. This study summarizes thousands of years of pre-Columbian history and medical evolution, specifically in the early and primitive practice of trephination, as precursors of neurosurgery. Comparative osteology studies have demonstrated that using primitive stone or metal instruments, the sirkaks (Inca surgeons) achieved an average survival rate of 50 to 70% of their craniectomy patients, with little incidence of infection or other complications. Despite their rudimentary knowledge of disease and pathology, a considerable knowledge of anatomy and natural medicine provided them with hemostatic agents, antiseptics, and other medical drugs, such as quinine for fever and malaria, as well as gold, silver, and other products to perform cranioplasties. Living in a world of continuous hand-to-hand combat, they also developed aggressive and defensive weapons that necessitated refinement of surgical techniques to save soldiers from battle wounds to their poorly protected crania.

  19. The bubble-like shape of the heliosphere observed by Voyager and Cassini

    Science.gov (United States)

    Dialynas, K.; Krimigis, S. M.; Mitchell, D. G.; Decker, R. B.; Roelof, E. C.

    2017-04-01

    For more than five decades, the shape and interactions of the heliosphere with the local interstellar medium have been discussed in the context of two competing models, posited in 1961 1 : a magnetosphere-like heliotail and a more symmetric bubble shape. Although past models broadly assumed the magnetosphere-like concept, the accurate heliospheric configuration remained largely undetermined due to lack of measurements. In recent years, however, Voyagers 1 and 2 (V1 and V2) crossed the termination shock — the boundary where the solar wind drops — north and south of the ecliptic plane at 94 au 2,3 and 84 au 4 in 2004 and 2007, respectively, and discovered the reservoir of ions and electrons that constitute the heliosheath, while Cassini remotely imaged the heliosphere 5 for the first time in 2003. Here we report 5.2-55 keV energetic neutral atom (ENA) global images of the heliosphere obtained with the Cassini/Ion and Neutral Camera (INCA). We compare them with 28-53 keV ions measured within the heliosheath by the low-energy charged particle (LECP) experiment onboard V1 and V2 over an 11-year period (2003-2014). We show that the heliosheath ions are the source of ENA. These observations also demonstrate that the heliosphere responds promptly, within ~2-3 years, to outward propagating solar wind changes in both the nose and tail directions. These results, together with the V1 measurement of a ~0.5 nT interstellar magnetic field 6 and the enhanced ratio between particle pressure and magnetic pressure in the heliosheath 7 , strongly suggest a diamagnetic bubble-like heliosphere with few substantial tail-like features. Our results are consistent with recent modelling 8-11 .

  20. The Cassini Solstice Mission: Streamlining Operations by Sequencing with PIEs

    Science.gov (United States)

    Vandermey, Nancy; Alonge, Eleanor K.; Magee, Kari; Heventhal, William

    2014-01-01

    The Cassini Solstice Mission (CSM) is the second extended mission phase of the highly successful Cassini/Huygens mission to Saturn. Conducted at a much-reduced funding level, operations for the CSM have been streamlined and simplified significantly. Integration of the science timeline, which involves allocating observation time in a balanced manner to each of the five different science disciplines (with representatives from the twelve different science instruments), has long been a labor-intensive endeavor. Lessons learned from the prime mission (2004-2008) and first extended mission (Equinox mission, 2008-2010) were utilized to design a new process involving PIEs (Pre-Integrated Events) to ensure the highest priority observations for each discipline could be accomplished despite reduced work force and overall simplification of processes. Discipline-level PIE lists were managed by the Science Planning team and graphically mapped to aid timeline deconfliction meetings prior to assigning discrete segments of time to the various disciplines. Periapse segments are generally discipline-focused, with the exception of a handful of PIEs. In addition to all PIEs being documented in a spreadsheet, allocated out-of-discipline PIEs were entered into the Cassini Information Management System (CIMS) well in advance of timeline integration. The disciplines were then free to work the rest of the timeline internally, without the need for frequent interaction, debate, and negotiation with representatives from other disciplines. As a result, the number of integration meetings has been cut back extensively, freeing up workforce. The sequence implementation process was streamlined as well, combining two previous processes (and teams) into one. The new Sequence Implementation Process (SIP) schedules 22 weeks to build each 10-week-long sequence, and only 3 sequence processes overlap. This differs significantly from prime mission during which 5-week-long sequences were built in 24 weeks

  1. The Cassini Solstice Mission: Streamlining Operations by Sequencing with PIEs

    Science.gov (United States)

    Vandermey, Nancy; Alonge, Eleanor K.; Magee, Kari; Heventhal, William

    2014-01-01

    The Cassini Solstice Mission (CSM) is the second extended mission phase of the highly successful Cassini/Huygens mission to Saturn. Conducted at a much-reduced funding level, operations for the CSM have been streamlined and simplified significantly. Integration of the science timeline, which involves allocating observation time in a balanced manner to each of the five different science disciplines (with representatives from the twelve different science instruments), has long been a labor-intensive endeavor. Lessons learned from the prime mission (2004-2008) and first extended mission (Equinox mission, 2008-2010) were utilized to design a new process involving PIEs (Pre-Integrated Events) to ensure the highest priority observations for each discipline could be accomplished despite reduced work force and overall simplification of processes. Discipline-level PIE lists were managed by the Science Planning team and graphically mapped to aid timeline deconfliction meetings prior to assigning discrete segments of time to the various disciplines. Periapse segments are generally discipline-focused, with the exception of a handful of PIEs. In addition to all PIEs being documented in a spreadsheet, allocated out-of-discipline PIEs were entered into the Cassini Information Management System (CIMS) well in advance of timeline integration. The disciplines were then free to work the rest of the timeline internally, without the need for frequent interaction, debate, and negotiation with representatives from other disciplines. As a result, the number of integration meetings has been cut back extensively, freeing up workforce. The sequence implementation process was streamlined as well, combining two previous processes (and teams) into one. The new Sequence Implementation Process (SIP) schedules 22 weeks to build each 10-week-long sequence, and only 3 sequence processes overlap. This differs significantly from prime mission during which 5-week-long sequences were built in 24 weeks

  2. Tras las huella del silencio: Potosí, los incas y Toledo

    Directory of Open Access Journals (Sweden)

    Tristan Platt

    2010-12-01

    Full Text Available ¿Por qué los señores aymaras de Charcas y el Inca Paullo, después de entregar las minas de plata de Porco a Hernando Pizarro en 1538, guardaron silencio sobre Potosí (distante a unas pocas leguas, que no se descubrió hasta abril de 1545? Reuniendo un mosaico de datos aparentemente inconexos, este artículo revisa las versiones corrientes del descubrimiento del cerro e interroga un curioso silencio presente en las fuentes. Reconstruyendo una red previamente desconocida de incas y españoles, se propone que, más que el hallazgo providencial de un yanacona aislado (la versión recibida, Potosí se manifestó como continuación de la política de “obediencia” subyacente en la entrega de Porco, ahora dirigida por el rival del Inca Paullo: el Inca Manco refugiado en Vilcabamba. Esta política de Manco buscaba apoyar al Rey y las Nuevas Leyes (1542 en contra de la amenaza mayor representada por Gonzalo Pizarro y los encomenderos. El artículo comenta, asimismo, la promoción toledana de la “leyenda providencial”, retomando en cambio la interpretación de Guaman Poma de la entrega de Potosí como una iniciativa de los incas, quienes lo habrían fundado bajo Inca Túpac Yupanqui. Esta versión concuerda con las últimas investigaciones geológicas y arqueológicas.

  3. Cassini's Grand Finale: The Final Orbits

    Science.gov (United States)

    Spilker, Linda; Edgington, Scott

    2016-04-01

    The Cassini-Huygens mission, a joint collaboration between NASA, ESA and the Italian Space Agency, is approaching its last year of operations after nearly 12 years in orbit around Saturn. Cassini will send back its final bits of unique data on September 15th, 2017 as it plunges into Saturn's atmosphere, vaporizing and satisfying planetary protection requirements. Before that time Cassini will continue its legacy of exploration and discovery with 12 close flybys of Titan in 2016 and 2017 that will return new science data as well as sculpt the inclinations and periods of the final orbits. Even though all of our close icy satellite flybys, including those of Enceladus, are now completed, numerous Voyager-class flybys (summer solstice approaches. In November 2016 Cassini will transition to a series of orbits with peripases just outside Saturn's F ring. These 20 orbits will include close flybys of some tiny ring moons and excellent views of the F ring and outer A ring. The 126th and final close flyby of Titan will propel Cassini across Saturn's main rings and into its final orbits. Cassini's Grand Finale, starting in April 2017, is comprised of 22 orbits at an inclination of 63 degrees. Cassini will repeatedly dive between the innermost rings and the upper atmosphere of the planet providing insights into fundamental questions unattainable during the rest of the mission. Cassini will be the first spacecraft to explore this region. These close orbits provide the highest resolution observations of both the rings and Saturn, and direct in situ sampling of the ring particles, composition, plasma, Saturn's exosphere and the innermost radiation belts. Saturn's gravitational field will be measured to unprecedented accuracy, providing information on the interior structure of the planet, winds in the outer layers of Saturn's atmosphere, and the mass distribution in the rings. Probing the magnetic field will give insight into the nature of the magnetic dynamo, telling us: why the

  4. Chlamydia trachomatis IncA Is Localized to the Inclusion Membrane and Is Recognized by Antisera from Infected Humans and Primates†

    OpenAIRE

    Bannantine, John P.; Walter E. Stamm; Suchland, Robert J.; Rockey, Daniel D.

    1998-01-01

    Chlamydia psittaci produces a collection of proteins, termed IncA, IncB, and IncC, that are localized to the chlamydial inclusion membrane. In this report we demonstrate that IncA is also produced by Chlamydia trachomatis. C. trachomatis IncA is structurally similar to C. psittaci IncA and is also localized to the inclusion membrane. Immunoblot analysis demonstrated that sera from C. trachomatis-infected patients and from experimentally infected monkeys both recognized C. trachomatis IncA.

  5. Equatorial distributions of energetic ion moments in Saturn's magnetosphere using Cassini/MIMI measurements

    Science.gov (United States)

    Dialynas, K.; Roussos, E.; Regoli, L.; Paranicas, C.; Krimigis, S. M.; Kane, M.; Mitchell, D. G.; Hamilton, D. C.

    2016-12-01

    We use kappa distribution fits to combined Charge Energy Mass Spectrometer (CHEMS, 3 to 236 keV/e), Low Energy Magnetosphere Measurements System (LEMMS, 0.024 INCA, 5.2 to >220 keV for H+) proton and singly ionized energetic ion spectra to calculate the >20 keV energetic ion moments inside Saturn's magnetosphere. Using a realistic magnetic field model (Khurana et al. 2007) and data from the entire Cassini mission to date (2004-2016), we map the ion measurements to the equatorial plane and via the modeled kappa distribution spectra we produce the equatorial distributions of all ion integral moments, focusing on partial density, integral intensity, partial pressure, integral energy intensity; as well as the characteristic energy (EC=IE/In), Temperature and κ-index of these ions as a function of Local Time (00:00 to 24:00 hrs) and L-Shell (5-20). A modified version of the semi-empirical Roelof and Skinner [2000] model is then utilized to retrieve the equatorial H+ and O+ pressure, density and temperature in Saturn's magnetosphere in both local time and L-shell. We find that a) although the H+ and O+ partial pressures and densities are nearly comparable, the >20 keV protons have higher number and energy intensities at all radial distances (L>5) and local times; b) the 12

  6. The Cassini Imaging Science Subsystem: Science Today and in Cassini's Final Three Years

    Science.gov (United States)

    West, R. A.

    2014-12-01

    The Cassini Imaging Science Subsystem (ISS) instrument was designed for long-range, high resolution imaging of Saturn and its system of rings and moons. It consists of two cameras, a Narrow Angle Camera (NAC, 2000 mm focal length) and a Wide Angle Camera (WAC, 200 mm focal length). The NAC has sensitivity from 200 nm to 1100 nm. The WAC is sensitive from 350 nm to 1100 nm. Among the mission highlights thus far for ISS have been discoveries of particulate plumes from Enceladus, details of surface topography along the 'tiger stripes', the discovery of an equatorial ridge on Iapetus, detailed images of small inner moons and distant moons Phoebe and Hyperion, features in Saturn's rings including perturbed edges near embedded moons, 'propellers', ephemeral clumps, and evidence for impacts in the rings and free-oscillation modes in Saturn's interior. The camera documented the aftermath of a methane/ethane 'rain' storm on Titan as well as seasonal behavior in the detached haze and visible airglow generated by magnetospheric plasma. The cameras documented the formation and evolution of a giant storm on Saturn, lightning from storms on Saturn, and determined that eddies are powering Saturn's zonal jets. In the F-ring and Proximal orbits ISS will obtain even better resolution on the rings, planet and inner moons.

  7. Estimation of Enceladus Plume Density Using Cassini Flight Data

    Science.gov (United States)

    Wang, Eric K.; Lee, Allan Y.

    2011-01-01

    The Cassini spacecraft was launched on October 15, 1997 by a Titan 4B launch vehicle. After an interplanetary cruise of almost seven years, it arrived at Saturn on June 30, 2004. In 2005, Cassini completed three flybys of Enceladus, a small, icy satellite of Saturn. Observations made during these flybys confirmed the existence of water vapor plumes in the south polar region of Enceladus. Five additional low-altitude flybys of Enceladus were successfully executed in 2008-9 to better characterize these watery plumes. During some of these Enceladus flybys, the spacecraft attitude was controlled by a set of three reaction wheels. When the disturbance torque imparted on the spacecraft was predicted to exceed the control authority of the reaction wheels, thrusters were used to control the spacecraft attitude. Using telemetry data of reaction wheel rates or thruster on-times collected from four low-altitude Enceladus flybys (in 2008-10), one can reconstruct the time histories of the Enceladus plume jet density. The 1 sigma uncertainty of the estimated density is 5.9-6.7% (depending on the density estimation methodology employed). These plume density estimates could be used to confirm measurements made by other onboard science instruments and to support the modeling of Enceladus plume jets.

  8. Dust occultation at Titan measured by CDA onboard Cassini

    Science.gov (United States)

    Srama, Ralf; CDA science Team

    2016-10-01

    The Cosmic Dust Analyzer (CDA) onboard Cassini characterized successfully the dust environment at Saturn since 2004. The instrument measures the primary charge, speed, mass and composition of individual submicron and micron sized dust grains. The detection threshold scales with speed^3.5 such that the detection of fast nanograins (~100 km/s) is possible. Saturn's nanodust environment (streams) is studied many years. However, a special geometric condition of Saturn, Cassini and Titan during a Titan flyby in 2014 (DOY 65) provided a special dust occultation opportunity. Titan and its atmosphere blocked the stream of fast nanoparticles such that CDA registered a clear drop in impact rate around closest approach. An analysis of the data allows to constrain the source region of the nanograins, which is compatible with a source region in the ring plane at distances from Saturn between 4 and 8 Saturn radii. Backward and forward modeling was performed leading to dust grain sizes between 3 and 9 nm and speeds between 80 and 150 km/s. The new modeling results also show that Enceladus acts a direct source for nanodust streams leading to the observation of periodic impact rates in the outer Saturn system. Such periodicities were observed recently by CDA and showed a clear signature of the Enceladus orbital period. A second dust occultation opportunity using Titan is planned august 2016.

  9. Cassini observations of carbon-based anions in Titan's ionosphere

    Science.gov (United States)

    Desai, Ravindra; Lewis, Gethyn; Waite, J. Hunter; Kataria, Dhiren; Wellbrock, Anne; Jones, Geraint; Coates, Andrew

    2016-07-01

    Cassini observations of Titan's ionosphere revealed an atmosphere rich in positively and negatively charged ions and organic molecules. The detection of large quantities of negatively charged ions was particularly surprising and adds Titan to the growing list of locations where anion chemistry has been observed to play an important role. In this study we present updated analysis on these negatively charged ions through an enhanced understanding of the Cassini CAPS Electron Spectrometer (CAPS-ELS) instrument response. The ionisation of Titan's dominant atmospheric constituent, N2, by the HeII Solar line, results in an observable photoelectron population at 24.1eV which we use to correct for differential spacecraft charging. Correcting for further energy-angle signatures within this dataset, we use an updated fitting procedure to show how the ELS mass spectrum, previously grouped into broad mass ranges, can be resolved into specific peaks at multiples of carbon-based anion species up to over 100amu/q. These peaks are shown to be ubiquitous within Titan's upper atmosphere and reminiscent of carbon-based anions identified in dense molecular clouds beyond our Solar System. It is thus shown how the moon Titan in the Outer Solar System can be used as an analogue to study these even more remote and exotic astrophysical environments.

  10. Planetary turbulence: survey of Cassini data in the Saturn's magnetosheath

    Science.gov (United States)

    Hadid, Lina; Sahraoui, Fouad; Kiyani, Khurom; Modolo, Ronan; Retino, Alessandro; Canu, Patrick; Masters, Adam; Dougherty, Michele K.; Gurnett, Donald A.

    2015-04-01

    Turbulence is one of the most important yet not fully understood topics of modern physics. Understanding turbulence is collisionless plasmas, where kinetic effects mediate interactions between fields and charged particles play, is crucial to apprehend many dynamical processes such as particle heating and acceleration. Among others, one key open issue of plasma turbulence is how the energy associated to magnetic and electric fields is converted, and eventually dissipated, into kinetic and internal energy of the plasma. The planets' magnetosheath present a high level of turbulence that involves both nonlinear stochastic processes and a rich variety of wave phenomena. In comparison with turbulence in the solar wind and in the terrestrial magnetosheath, turbulence around other planets is far less explored. Here, we expand our knowledge in plasma turbulence by exploring the properties of turbulence in the Kronian magnetosheath using the Cassini spacecraft data. These properties include the magnetic field energy spectra, the magnetic compressibility and intermittency at both MHD and kinetic scales. The analysis is based on in-situ data provided by the Fluxgate Magnetometer of the MAG instrument, which measures the magnetic field data with 32ms time resolution and the plasma data from the CAPS/IMS (Cassini Plasma Spectrometer) and the Electron Spectrometer (ELS), during 39 shock-crossings between 2004 and 2005. Similarities and differences with the solar wind were found, in particular about the nature of the turbulence and its scaling laws, as well as the dependence of those properties on the topology of the bow shock.

  11. Exploring Plasma Turbulence in the Kronian Magnetosheath Using Cassini Data

    Science.gov (United States)

    Hadid, L.; Sahraoui, F.; Kiyani, K. H.; Modolo, R.; Retino, A.; Canu, P.; Masters, A.; Dougherty, M. K.

    2014-12-01

    The shocked solar wind plasma upstream of the bowshock forms the magnetosheath. Through this region energy, mass and momentum are transported from the solar wind into the planet's magnetosphere, playing a crucial role in the solar-planet interactions. Hence, the planets' magnetosheath present a high level of turbulence, with a rich variety of wave and stochastic phenomena. While the magnetic turbulence of the terrestrial magnetosheath has been extensively studied, not so much work has been done regarding the planets magnetosheaths. Therefore, and in order to expand our knowledge on plasma turbulence, we investigate here the main properties of the plasma turbulence in the magnetosheath of Saturn using the Cassini spacecraft data and compare it with the well-explored terrestrial solar wind turbulence. These properties include the magnetic field energy spectra, the magnetic compressibility and intermittency, at both MHD and kinetic scales. The analysis is based on in-situ data provided by the Fluxgate Magnetometer of the MAG instrument, which measures the magnetic field data with 32ms time resolution and the plasma data from the CAPS/IMS (Cassini Plasma Spectrometer) and the Electron Spectrometer (ELS), during 39 shock-crossings between 2004 and 2005. Similarities and differences were found between the different media, in particular about the nature of the turbulence and its scaling laws. These finding will be discussed along with theoretical implications on the modeling of space plasma.

  12. Abundances of Jupiter's Trace Hydrocarbons From Voyager and Cassini

    CERN Document Server

    Nixon, Conor A; Romani, Paul N; Allen, Mark; Zhang, Xi; Teanby, Nicholas A; Irwin, Patrick G J; Flasar, F Michael; 10.1016/j.pss2010.05.08

    2010-01-01

    The flybys of Jupiter by the Voyager spacecraft in 1979, and over two decades later by Cassini in 2000, have provided us with unique datasets from two different epochs, allowing the investigation of seasonal change in the atmosphere. In this paper we model zonal averages of thermal infrared spectra from the two instruments, Voyager 1 IRIS and Cassini CIRS, to retrieve the vertical and meridional profiles of temperature, and the abundances of the two minor hydrocarbons, acetylene (C2H2) and ethane (C2H6). The spatial variation of these gases is controlled by both chemistry and dynamics, and therefore their observed distribution gives us an insight into both processes. We find that the two gases paint quite different pictures of seasonal change. Whilst the 2-D cross-section of C2H6 abundance is slightly increased and more symmetric in 2000 (northern summer solstice) compared to 1979 (northern fall equinox), the major trend of equator to pole increase remains. For C2H2 on the other hand, the Voyager epoch exhibi...

  13. Cassini State Transitions with a Fossil Figure

    Science.gov (United States)

    Matsuyama, Isamu; Tuttle Keane, James

    2016-10-01

    The Moon has experienced large obliquity variations during Cassini state transitions which greatly impact tidal heating, and the long-term stability of polar volatiles. It has been known for centuries that the lunar rotational and tidal bulges are much larger than expected. The South Pole-Aitken basin can explain a large fraction of the excess deformation. Accounting for the contribution of this basin (and other large basins), the remaining excess deformation arises due to a fossil figure established when the Moon orbited much closer to Earth than it does today. Previous studies assume that the present, excess deformation is entirely preserved throughout Cassini state transitions. This ignores basin contributions to the excess deformation, and requires an interior with infinite rigidity. We consider Cassini state transition models that take into account basin contributions to the excess deformation, and the effect of finite rigidity on the fossil figure.

  14. Seasonal variability of upper tropospheric acetone using ACE-FTS observations and LMDz-INCA model simulations

    Science.gov (United States)

    Dufour, Gaëlle; Harrison, Jeremy; Szopa, Sophie; Bernath, Peter

    2014-05-01

    The vertically-resolved distributions of oxygenated organic compounds (oVOCs) are mainly inferred from surface and airborne measurements with limited spatial and temporal coverage. This results in a limited understanding of the atmospheric budget of these compounds and of their impact on the upper tropospheric chemistry. In the last decade, satellite observations which complement in-situ measurements have become available, providing global distributions of several oVOCs. For example, Scisat-1, also known as the Atmospheric Chemistry Experiment (ACE) has measured several oVOCs including methanol and formaldehyde. ACE is a Canadian-led satellite mission for remote sensing of the Earth's atmosphere that has been in operation since 2004. The primary instrument on board is a Fourier transform spectrometer (FTS) featuring broad spectral coverage in the infrared (750-4400 cm-1) with high spectral resolution (0.02 cm-1). The FTS instrument can measure down to 5 km altitude with a high signal-to-noise ratio using solar occultation. The ACE-FTS has the ability to measure seasonal and height-resolved distributions of minor tropospheric constituents on a near-global scale and provides the opportunity to evaluate our understanding of important atmospheric oxygenated organic species. ACE-FTS acetone retrievals will be presented. The spatial distribution and seasonal variability of acetone will be described and compared to LMDz-INCA model simulations.

  15. Cassini Solstice Mission Maneuver Experience: Year Three

    Science.gov (United States)

    Wagner, Sean V.; Arrieta, Juan; Hahn, Yungsun; Stumpf, Paul W.; Valerino, Powtawche N.; Wong, Mau C.

    2013-01-01

    The Solstice Mission is the final extension of the Cassini spacecraft s tour of Saturn and its moons. To accommodate an end-of-mission in 2017, the maneuver decision process has been refined. For example, the Cassini Project now prioritizes saving propellant over minimizing maneuver cycles. This paper highlights 30 maneuvers planned from June 2012 through July 2013, targeted to nine Titan flybys and the final Rhea encounter in the mission. Of these maneuvers, 90% were performed to maintain the prescribed trajectory and preserve downstream delta V. Recent operational changes to maneuver executions based on execution-error modeling and analysis are also discussed.

  16. Cassini Solstice Mission Maneuver Experience: Year One

    Science.gov (United States)

    Wagner, Sean V.; Arrieta, Juan; Ballard, Christopher G.; Hahn, Yungsun; Stumpf, Paul W.; Valerino, Powtawche N.

    2011-01-01

    The Cassini-Huygens spacecraft began its four-year Prime Mission to study Saturn's system in July 2004. Two tour extensions followed: a two-year Equinox Mission beginning in July 2008 and a seven-year Solstice Mission starting in September 2010. This paper highlights Cassini maneuver activities from June 2010 through June 2011, covering the transition from the Equinox to Solstice Mission. This interval included 38 scheduled maneuvers, nine targeted Titan flybys, three targeted Enceladus flybys, and one close Rhea flyby. In addition, beyond the demanding nominal navigation schedule, numerous unforeseen challenges further complicated maneuver operations. These challenges will be discussed in detail.

  17. ¿Borradores utópicos del pasado? El poema Apu Inca Atawallpaman

    DEFF Research Database (Denmark)

    Jeppesen, Anne Marie Ejdesgaard; Schilling Cueto, Chandra Eugenie A.

    2016-01-01

    We discuss the perceptions of the relationship between the human being and the nature which comes forward in the poem Apu Inca Atawallpaman as possible utopian drafts or another knowledge from the past using for our analysis the concepts of Eduardo Gudynas and Walter Mignolo. We suggest...

  18. An α-helical core encodes the dual functions of the chlamydial protein IncA.

    Science.gov (United States)

    Ronzone, Erik; Wesolowski, Jordan; Bauler, Laura D; Bhardwaj, Anshul; Hackstadt, Ted; Paumet, Fabienne

    2014-11-28

    Chlamydia is an intracellular bacterium that establishes residence within parasitophorous compartments (inclusions) inside host cells. Chlamydial inclusions are uncoupled from the endolysosomal pathway and undergo fusion with cellular organelles and with each other. To do so, Chlamydia expresses proteins on the surface of the inclusion using a Type III secretion system. These proteins, termed Incs, are located at the interface between host and pathogen and carry out the functions necessary for Chlamydia survival. Among these Incs, IncA plays a critical role in both protecting the inclusion from lysosomal fusion and inducing the homotypic fusion of inclusions. Within IncA are two regions homologous to eukaryotic SNARE (soluble N-ethylmaleimide-sensitive factor attachment receptor) domains referred to as SNARE-like domain 1 (SLD1) and SNARE-like domain 2 (SLD2). Using a multidisciplinary approach, we have discovered the functional core of IncA that retains the ability to both inhibit SNARE-mediated fusion and promote the homotypic fusion of Chlamydia inclusions. Circular dichroism and analytical ultracentrifugation experiments show that this core region is composed almost entirely of α-helices and assembles into stable homodimers in solution. Altogether, we propose that both IncA functions are encoded in a structured core domain that encompasses SLD1 and part of SLD2. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  19. Couriers in the Inca Empire: Getting Your Message Across. [Lesson Plan].

    Science.gov (United States)

    2002

    This lesson shows how the Inca communicated across the vast stretches of their mountain realm, the largest empire of the pre-industrial world. The lesson explains how couriers carried messages along mountain-ridge roads, up and down stone steps, and over chasm-spanning footbridges. It states that couriers could pass a message from Quito (Ecuador)…

  20. The complete mitogenome of a 500-year-old Inca child mummy.

    Science.gov (United States)

    Gómez-Carballa, Alberto; Catelli, Laura; Pardo-Seco, Jacobo; Martinón-Torres, Federico; Roewer, Lutz; Vullo, Carlos; Salas, Antonio

    2015-11-12

    In 1985, a frozen mummy was found in Cerro Aconcagua (Argentina). Archaeological studies identified the mummy as a seven-year-old Inca sacrifice victim who lived >500 years ago, at the time of the expansion of the Inca Empire towards the southern cone. The sequence of its entire mitogenome was obtained. After querying a large worldwide database of mitogenomes (>28,000) we found that the Inca haplotype belonged to a branch of haplogroup C1b (C1bi) that has not yet been identified in modern Native Americans. The expansion of C1b into the Americas, as estimated using 203 C1b mitogenomes, dates to the initial Paleoindian settlements (~18.3 thousand years ago [kya]); however, its internal variation differs between Mesoamerica and South America. By querying large databases of control region haplotypes (>150,000), we found only a few C1bi members in Peru and Bolivia (e.g. Aymaras), including one haplotype retrieved from ancient DNA of an individual belonging to the Wari Empire (Peruvian Andes). Overall, the results suggest that the profile of the mummy represents a very rare sub-clade that arose 14.3 (5-23.6) kya and could have been more frequent in the past. A Peruvian Inca origin for present-day C1bi haplotypes would satisfy both the genetic and paleo-anthropological findings.

  1. An α-Helical Core Encodes the Dual Functions of the Chlamydial Protein IncA*

    Science.gov (United States)

    Ronzone, Erik; Wesolowski, Jordan; Bauler, Laura D.; Bhardwaj, Anshul; Hackstadt, Ted; Paumet, Fabienne

    2014-01-01

    Chlamydia is an intracellular bacterium that establishes residence within parasitophorous compartments (inclusions) inside host cells. Chlamydial inclusions are uncoupled from the endolysosomal pathway and undergo fusion with cellular organelles and with each other. To do so, Chlamydia expresses proteins on the surface of the inclusion using a Type III secretion system. These proteins, termed Incs, are located at the interface between host and pathogen and carry out the functions necessary for Chlamydia survival. Among these Incs, IncA plays a critical role in both protecting the inclusion from lysosomal fusion and inducing the homotypic fusion of inclusions. Within IncA are two regions homologous to eukaryotic SNARE (soluble N-ethylmaleimide-sensitive factor attachment receptor) domains referred to as SNARE-like domain 1 (SLD1) and SNARE-like domain 2 (SLD2). Using a multidisciplinary approach, we have discovered the functional core of IncA that retains the ability to both inhibit SNARE-mediated fusion and promote the homotypic fusion of Chlamydia inclusions. Circular dichroism and analytical ultracentrifugation experiments show that this core region is composed almost entirely of α-helices and assembles into stable homodimers in solution. Altogether, we propose that both IncA functions are encoded in a structured core domain that encompasses SLD1 and part of SLD2. PMID:25324548

  2. Story Starters on the Aztecs, Incas, and Mayas. A Creative Writing Program.

    Science.gov (United States)

    Henrich, Steve; Henrich, Jean

    Designed to supplement an established language arts and social studies program, this books deals with the Aztecs, Incas, and Mayas of Latin America. All of the "Story Starter" books are intended to give a variety of vocabulary and story ideas to help with the writing process. Each of the books is divided into four main sections: (1) an…

  3. Los tambos Inca: el caso de Camata Tambo valle alto de Moquegua

    OpenAIRE

    2013-01-01

    Camata Tambo está ubicado en la parte alta del valle alto de Moquegua. Por este tambo pasa un camino Inca que viene del altiplano y continúa hacia el centro provincial de Sabaya ubicado a 1 km valle abajo.

  4. Story Starters on the Aztecs, Incas, and Mayas. A Creative Writing Program.

    Science.gov (United States)

    Henrich, Steve; Henrich, Jean

    Designed to supplement an established language arts and social studies program, this books deals with the Aztecs, Incas, and Mayas of Latin America. All of the "Story Starter" books are intended to give a variety of vocabulary and story ideas to help with the writing process. Each of the books is divided into four main sections: (1) an…

  5. Los tambos Inca: el caso de Camata Tambo valle alto de Moquegua

    OpenAIRE

    Chacaltana Cortez, Sofía; Ministerio de Cultura

    2013-01-01

    Camata Tambo está ubicado en la parte alta del valle alto de Moquegua. Por este tambo pasa un camino Inca que viene del altiplano y continúa hacia el centro provincial de Sabaya ubicado a 1 km valle abajo.

  6. Radiocarbon dating of the Peruvian Chachapoya/Inca site at the Laguna de los Condores

    Energy Technology Data Exchange (ETDEWEB)

    Wild, Eva Maria [Vienna Environmental Research Accelerator (VERA) Laboratory, Fakultaet fuer Physik, Universitaet Wien, Waehringer Str. 17, A-1090 Vienna (Austria)]. E-mail: eva.maria.wild@univie.ac.at; Guillen, Sonia [Centro Mallqui, The Bioanthropology Foundation Peru, Ilo (Peru); Kutschera, Walter [Vienna Environmental Research Accelerator (VERA) Laboratory, Fakultaet fuer Physik, Universitaet Wien, Waehringer Str. 17, A-1090 Vienna (Austria); Seidler, Horst [Department fuer Anthropologie, Universitaet Wien, Althanstrasse 14, A-1090 Vienna (Austria); Steier, Peter [Vienna Environmental Research Accelerator (VERA) Laboratory, Fakultaet fuer Physik, Universitaet Wien, Waehringer Str. 17, A-1090 Vienna (Austria)

    2007-06-15

    In 1997 a new archaeological site was discovered in the Peruvian tropical rain forest. The site is located in an area which has been occupied by the Chachapoya, a pre-Incan people, from about 800AD on. The site comprises a large funerary place with several mausoleums built in the cliffs next to the Laguna de los Condores. More than 200 human mummies and funerary bone-bundles together with numerous grave artefacts have been found there. Although the site has been ascribed to the Chachapoya, the mummification method used is very similar to the one applied by the Inca. As part of an ongoing multidisciplinary project to explore the history of this site and of the Chachapoya people, twenty-seven (27) {sup 14}C-AMS age determinations were performed. Samples, bones and textile wrappings as well as samples from a funerary bone bundle plus associated grave artefacts were dated. The {sup 14}C data show that the site originates from the Chachapoya pre-Inca period and that in addition, it was used as a funerary place during the subsequent Inca occupation era. The radiocarbon results indicate that the Chachapoya may have changed their burial tradition due to the colonization by the Inca.

  7. Preclinical evaluation of (111)In-DTPA-INCA-X anti-Ku70/Ku80 monoclonal antibody in prostate cancer.

    Science.gov (United States)

    Evans-Axelsson, Susan; Vilhelmsson Timmermand, Oskar; Welinder, Charlotte; Borrebaeck, Carl Ak; Strand, Sven-Erik; Tran, Thuy A; Jansson, Bo; Bjartell, Anders

    2014-01-01

    The aim of this investigation was to assess the Ku70/Ku80 complex as a potential target for antibody imaging of prostate cancer. We evaluated the in vivo and ex vivo tumor targeting and biodistribution of the (111)In-labeled human internalizing antibody, INCA-X ((111)In-DTPA-INCA-X antibody), in NMRI-nude mice bearing human PC-3, PC-3M-Lu2 or DU145 xenografts. DTPA-conjugated, non-labeled antibody was pre-administered at different time-points followed by a single intravenous injection of (111)In-DTPA-INCA-X. At 48, 72 and 96 h post-injection, tissues were harvested, and the antibody distribution was determined by measuring radioactivity. Preclinical SPECT/CT imaging of mice with and without the predose was performed at 48 hours post-injection of labeled DTPA-INCA-X. Biodistribution of the labeled antibody showed enriched activity in tumor, spleen and liver. Animals pre-administered with DTPA-INCA-X showed increased tumor uptake and blood content of (111)In-DTPA-INCA-X with reduced splenic and liver uptake. The in vitro and in vivo data presented show that the (111)In-labeled INCA-X antibody is internalized into prostate cancer cells and by pre-administering non-labeled DTPA-INCA-X, we were able to significantly reduce the off target binding and increase the (111)In-DTPA-INCA-X mAb uptake in PC-3, PC-3M-Lu2 and DU145 xenografts. The results are encouraging and identifying the Ku70/Ku80 antigen as a target is worth further investigation for functional imaging of prostate cancer.

  8. Preclinical evaluation of 111In-DTPA-INCA-X anti-Ku70/Ku80 monoclonal antibody in prostate cancer

    Science.gov (United States)

    Evans-Axelsson, Susan; Vilhelmsson Timmermand, Oskar; Welinder, Charlotte; Borrebaeck, Carl AK; Strand, Sven-Erik; Tran, Thuy A; Jansson, Bo; Bjartell, Anders

    2014-01-01

    The aim of this investigation was to assess the Ku70/Ku80 complex as a potential target for antibody imaging of prostate cancer. We evaluated the in vivo and ex vivo tumor targeting and biodistribution of the 111In-labeled human internalizing antibody, INCA-X (111In-DTPA-INCA-X antibody), in NMRI-nude mice bearing human PC-3, PC-3M-Lu2 or DU145 xenografts. DTPA-conjugated, non-labeled antibody was pre-administered at different time-points followed by a single intravenous injection of 111In-DTPA-INCA-X. At 48, 72 and 96 h post-injection, tissues were harvested, and the antibody distribution was determined by measuring radioactivity. Preclinical SPECT/CT imaging of mice with and without the predose was performed at 48 hours post-injection of labeled DTPA-INCA-X. Biodistribution of the labeled antibody showed enriched activity in tumor, spleen and liver. Animals pre-administered with DTPA-INCA-X showed increased tumor uptake and blood content of 111In-DTPA-INCA-X with reduced splenic and liver uptake. The in vitro and in vivo data presented show that the 111In-labeled INCA-X antibody is internalized into prostate cancer cells and by pre-administering non-labeled DTPA-INCA-X, we were able to significantly reduce the off target binding and increase the 111In-DTPA-INCA-X mAb uptake in PC-3, PC-3M-Lu2 and DU145 xenografts. The results are encouraging and identifying the Ku70/Ku80 antigen as a target is worth further investigation for functional imaging of prostate cancer. PMID:24982817

  9. Peeling the Onion: The Upper Surface of Mimas from Cassini VIMS

    Science.gov (United States)

    Buratti, Bonnie J.; Brown, R. H.; Clark, R. N.; Mosher, J. A.; Cruikshank, D. P.; Filacchione, G.; Baines, K. H.; Nicholson, P. D.

    2010-10-01

    Cloaked in light from Saturn and its rings, the medium-sized Saturnian satellite Mimas is difficult to observe form Earth, and it was the only major satellite not to have a close encounter by the Cassini spacecraft. Observations of the moon during Ring Plane Crossing in 1995 and by the Hubble Space Telescope established that the moon has a visual geometric albedo of greater than unity (Verbiscer et al. 2007, Science 315, 815) and a brighter trailing side (Buratti et al. 1998, Icarus 136, 223), suggesting it is being coated by the E-ring. Observations at opposition obtained by the Cassini Visual Infrared Mapping Spectrometer (VIMS) instrument between 0.4 and 5.2 microns show the moon has a surge similar to that seen on other icy bodies, increasing in brightness by over 30% in the last five degrees. During the closest nontargeted flyby by Cassini on February 13, 2010, when the Cassini spacecraft approached within 9500 km of Mimas, maps of the moon were obtained by VIMS. Water ice absorption bands in the central peak and crater rim of Herschel are deeper than those in the surrounding regions. Preliminary results indicate the water ice grain size decreases as the distance from the apex of motion increases. No constituents other than water ice have yet been identified. Funded by NASA.

  10. A Functional Core of IncA Is Required for Chlamydia trachomatis Inclusion Fusion.

    Science.gov (United States)

    Weber, Mary M; Noriea, Nicholas F; Bauler, Laura D; Lam, Jennifer L; Sager, Janet; Wesolowski, Jordan; Paumet, Fabienne; Hackstadt, Ted

    2016-04-01

    Chlamydia trachomatis is an obligate intracellular pathogen that is the etiological agent of a variety of human diseases, including blinding trachoma and sexually transmitted infections. Chlamydiae replicate within a membrane-bound compartment, termed an inclusion, which they extensively modify by the insertion of type III secreted proteins called Inc proteins. IncA is an inclusion membrane protein that encodes two coiled-coil domains that are homologous to eukaryotic SNARE (soluble N-ethylmaleimide-sensitive factor attachment receptor) motifs. Recent biochemical evidence suggests that a functional core, composed of SNARE-like domain 1 (SLD-1) and part of SNARE-like domain 2 (SLD-2), is required for the characteristic homotypic fusion of C. trachomatis inclusions in multiply infected cells. To verify the importance of IncA in homotypic fusion in Chlamydia, we generated an incA::bla mutant. Insertional inactivation of incA resulted in the formation of nonfusogenic inclusions, a phenotype that was completely rescued by complementation with full-length IncA. Rescue of homotypic inclusion fusion was dependent on the presence of the functional core consisting of SLD-1 and part of SLD-2. Collectively, these results confirm in vitro membrane fusion assays identifying functional domains of IncA and expand the genetic tools available for identification of chlamydia with a method for complementation of site-specific mutants. Chlamydia trachomatis replicates within a parasitophorous vacuole termed an inclusion. The chlamydial inclusions are nonfusogenic with vesicles in the endocytic pathway but, in multiply infected cells, fuse with each other to form a single large inclusion. This homotypic fusion is dependent upon the presence of a chlamydial inclusion membrane-localized protein, IncA. Specificity of membrane fusion in eukaryotic cells is regulated by SNARE (soluble N-ethylmaleimide sensitive factor attachment receptor) proteins on the cytosolic face of vesicles and target

  11. INFORTUNIO Y VIRTUD: PETRARCA, VIVES Y EL INCA GARCILASO DE LA VEGA

    Directory of Open Access Journals (Sweden)

    Sarissa Carneiro

    2010-11-01

    Full Text Available Este ensayo analiza la relación entre infortunio y virtud en La Florida del Inca (1605 del mestizo cuzqueño Garcilaso de la Vega, estableciendo un diálogo con la filosofía moral del Renacimiento, en especial con De remediis utriusque fortunæ (1366 de Francesco Petrarca e Introductio ad sapientiam (1524 de Juan Luis Vives. Se destaca el relieve que adquieren, en la crónica primeriza del Inca, la valoración de la fortuna adversa, la preocupación por la “depravación” de los juicios, causada por el gobierno de las pasiones, y el aprovechamiento de la sabiduría de los indios como ejemplos de virtud para los cristianos. Se vincula, finalmente, la vertiente moral de la crónica del Inca con el ideal político y filosófico de la concordia entre el Viejo y el Nuevo Mundo.This essay aims to analyze the relationship between misfortune and virtue in La Florida del Inca (1605 by the mestizo Inca Garcilaso de la Vega, considering its dialogue with the moral philosophy of the Renaissance, in particular with De remediis utriusque fortunæ (1366 by Francesco Petrarca and Introductio ad sapientiam (1524 by Juan Luis Vives. The analysis emphasizes the importance of the value of misfortune, the consequences of the corruption of judgment, caused by the governance of passions, and the use of Indian wisdom as examples of virtue to Christian readers of the chronicle. Finally, the essay establishes a relationship between the moral positions of the text and its political and philosophical ideals of concord between the Old and New World.

  12. Managing Cassini Safe Mode Attitude at Saturn

    Science.gov (United States)

    Burk, Thomas A.

    2010-01-01

    The Cassini spacecraft was launched on October 15, 1997 and arrived at Saturn on June 30, 2004. It has performed detailed observations and remote sensing of Saturn, its rings, and its satellites since that time. In the event safe mode interrupts normal orbital operations, Cassini has flight software fault protection algorithms to detect, isolate, and recover to a thermally safe and commandable attitude and then wait for further instructions from the ground. But the Saturn environment is complex, and safety hazards change depending on where Cassini is in its orbital trajectory around Saturn. Selecting an appropriate safe mode attitude that insures safe operation in the Saturn environment, including keeping the star tracker field of view clear of bright bodies, while maintaining a quiescent, commandable attitude, is a significant challenge. This paper discusses the Cassini safe table management strategy and the key criteria that must be considered, especially during low altitude flybys of Titan, in deciding what spacecraft attitude should be used in the event of safe mode.

  13. The Attraction of Gravity (Jean Dominique Cassini Medal Lecture)

    Science.gov (United States)

    Iess, Luciano

    2017-04-01

    remains elusive, and much remains to be explored. New missions and new tools are needed. In the next five years the planetary community will see the launch of BepiColombo and JUICE, two spacecraft equipped with a powerful suite of instruments devoted to the tomography of Mercury and Ganymede. Innovative instrumentation and probes are being conceived and designed. The Cassini Medal Lecture will review the past successes and future trends of planetary geodesy and radio science, from the peculiar perspective of someone whose attraction for gravity kept him at the ill-defined boundary between science and engineering, measuring angles, distances and velocities in the solar system.

  14. Modernization of the Cassini Ground System

    Science.gov (United States)

    Razo, Gus; Fujii, Tammy

    2014-01-01

    The Cassini Spacecraft and its ground system have been operational for over 16 years. Modernization presents several challenges due to the personnel, processes, and tools already invested and embedded into the current ground system structure. Every mission's ground system has its own unique complexities and challenges, involving various organizational units. As any mission from its inception to its execution, schedules are always tight. This forces GDS engineers to implement a working ground system that is not necessarily fully optimized. Ground system challenges increase as technology evolves and cyber threats become more sophisticated. Cassini's main challenges were due to its ground system existing before many security requirements were levied on the multi-mission tools and networks. This caused a domino effect on Cassini GDS tools that relied on outdated technological features. In the aerospace industry reliable and established technology is preferred over innovative yet less proven technology. Loss of data for a spacecraft mission can be catastrophic; therefore, there is a reluctance to make changes and updates to the ground system. Nevertheless, all missions and associated teams face the need to modernize their processes and tools. Systems development methods from well-known system analysis and design principles can be applied to many missions' ground systems. Modernization should always be considered, but should be done in such a way that it does not affect flexibility nor interfere with established practices. Cassini has accomplished a secure and efficient ground data system through periodic updates. The obstacles faced while performing the modernization of the Cassini ground system will be outlined, as well as the advantages and challenges that were encountered.

  15. The inhibitor of growth protein 5 (ING5 depends on INCA1 as a co-factor for its antiproliferative effects.

    Directory of Open Access Journals (Sweden)

    Feng Zhang

    Full Text Available The proteins of the Inhibitor of Growth (ING family are involved in multiple cellular functions such as cell cycle regulation, apoptosis, and chromatin remodeling. For ING5, its actual role in growth suppression and the necessary partners are not known. In a yeast-two-hybrid approach with human bone marrow derived cDNA, we identified ING5 as well as several other proteins as interaction partners of Inhibitor of cyclin A1 (INCA1 that we previously characterized as a novel interaction partner of cyclin A1/CDK2. ING5 expression in leukemic AML blasts was severely reduced compared to normal bone marrow. In line, ING5 inhibited bone marrow colony formation upon retroviral transduction. However, Inca1(-/- bone marrow colony formation was not suppressed by ING5. In murine embryonic fibroblast (MEF cells from Inca1(+/+ and Inca1(-/- mice, overexpression of ING5 suppressed cell proliferation only in the presence of INCA1, while ING5 had no effect in Inca1(-/- MEFs. ING5 overexpression induced a delay in S-phase progression, which required INCA1. Finally, ING5 overexpression enhanced Fas-induced apoptosis in Inca1(+/+ MEFs, while Inca1(-/- MEFs were protected from Fas antibody-induced apoptosis. Taken together, these results indicate that ING5 is a growth suppressor with suppressed expression in AML whose functions depend on its interaction with INCA1.

  16. Assimilation of Polder aerosol optical thickness into LMD2-Inca model in order to study aerosol-climate interactions; Etude des interactions entre aerosols et climat: assimilation des observations spatiales de Polder dans LMDz-Inca

    Energy Technology Data Exchange (ETDEWEB)

    Generoso, S.

    2004-12-15

    Aerosols influence the Earth radiative budget both through their direct (scattering and absorption of solar radiation) and indirect (impacts on cloud microphysics) effects. The anthropogenic perturbation due to aerosol emissions is of the same order of magnitude than the one due to greenhouse gases, but less well known. To improve our knowledge, we need to better know aerosol spatial and temporal distributions. Indeed, aerosol modeling still suffers from large uncertainties in sources and transport, while satellite observations are incomplete (no detection in the presence of clouds, no information on the vertical distribution or on the chemical nature). Moreover, field campaigns are localized in space and time. This study aims to reduce uncertainties in aerosol distributions, developing assimilation of satellite data into a chemical transport model. The basic idea is to combine information obtained from spatial observation (optical thickness) and modeling studies (aerosol types, vertical distribution). In this study, we assimilate data from the POLDER space-borne instrument into the LMDz-INCA model. The results show the advantage of merging information from different sources. In many regions, the method reduces uncertainties on aerosol distribution (reduction of RMS error). An application of the method to the study of aerosol impact on cloud microphysics is shown. (author)

  17. 世界首台Inca Onset S70印刷机落户英国印刷厂

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    英国IncaOnsetS70公司日前成为了IncaOnsetS70高端平板喷墨印刷机在全球的第一个用户。据了解,对大幅面销售点广告来说,数字印刷比胶印或丝网印刷更有优势。

  18. New knowledge in determining the astronomical orientation of Incas object in Ollantaytambo, Peru

    Science.gov (United States)

    Hanzalová, K.; Klokočník, J.; Kostelecký, J.

    2014-06-01

    This paper deals about astronomical orientation of Incas objects in Ollantaytambo, which is located about 35 km southeast from Machu Picchu, about 40 km northwest from Cusco, and lies in the Urubamba valley. Everybody writing about Ollantaytambo, shoud read Protzen (1993). He devoted his monograph to description and interpretation of that locality. Book of Salazar and Salazar (2005) deals, among others, with the orientation of objects in Ollantaytambo with respect to the cardinal direction. Zawaski and Malville (2007) documented astronomical context of major monuments of nine sites in Peru, including Ollantaytambo. We tested astronomical orientation in these places and confirm or disprove hypothesis about purpose of Incas objects. For assessment orientation of objects we used our measurements and also satellite images on Google Earth and digital elevation model from ASTER. The satellite images used to approximate estimation of astronomical orientation. The digital elevation model is useful in the mountains, where we need the really horizon for a calculation of sunset and sunrise on specific days (solstices), which were for Incas people very important. By Incas is very famous that they worshiped the Sun. According to him they determined when to plant and when to harvest the crop. In this paper we focused on Temple of the Sun, also known the Wall of six monoliths. We tested which astronomical phenomenon is connected with this Temple. First, we tested winter solstice sunrise and the rides of the Pleiades for the epochs 2000, 1500 and 1000 A.D. According with our results the Temple isn't connected neither with winter solstice sunrise nor with the Pleiades. Then we tested also winter solstice sunset. We tried to use the line from an observation point near ruins of the Temple of Sun, to west-north, in direction to sunset. The astronomical azimuth from this point was about 5° less then we need. From this results we found, that is possible to find another observation

  19. The Inca healer: empirical medical knowledge and magic in pre-Columbian Peru

    Directory of Open Access Journals (Sweden)

    Elferink, Jan G. R.

    2015-08-01

    Full Text Available The role of medical practitioners among the Incas is addressed, based on archeological findings and especially the writings of the Spanish chroniclers. In Inca medicine a large role was reserved for religion and magic but at the same time an extensive knowledge of medicinal plants was available. As a consequence there were several types of healers who cured with a mixture of medicinal plants and religious-magic ceremonies. The hampicamayoc or ‘official in charge of medicines’ was the one who resembled somewhat the European physician of that time and was the most important type of healer. He relied largely but certainly not exclusively on the use of medicinal plants. There were also healers who cured mainly with religious-magic procedures. Surgery must have been important for the Inca healer but this is hardly reflected in the work of the Spanish chroniclers.La posición social de los profesionales de la medicina en la Cultura Inca se conoce gracias a los hallazgos arqueológicos y, sobre todo, gracias a los escritos de los cronistas españoles. En la medicina Inca, la religión y la magia ocupaban un papel destacado, aunque también era importante el conocimiento de las plantas medicinales. En consecuencia, existieron distintos tipos de curanderos que curaban con una mezcla más o menos mayor de plantas medicinales y ceremonias religiosas y mágicas. El hampicamayoc o «funcionario encargado de los medicamentos» sobresalía entre los curanderos y tenía cierto parecido con el médico europeo de la época. Su actuación se basaba sobre todo, aunque no exclusivamente, en el uso de plantas medicinales. Otros, en cambio, curaban básicamente con procedimientos mágicoreligiosos. La cirugía debió ser importante para el sanador Inca pero este hecho apenas se refleja en la obra de los cronistas españoles.

  20. Cassini's Grand Finale and Recent Science Highlights

    Science.gov (United States)

    Spilker, Linda J.

    2017-06-01

    After almost 13 years in Saturn orbit, the Cassini-Huygens mission has entered its final year of data collection. Cassini will return its final bits of unique data on 15 September 2017 as it plunges into Saturn’s atmosphere, vaporizing and satisfying planetary protection requirements.Since early 2016 Cassini’s orbital inclination was slowly increased towards its final inclination. In November Cassini transitioned to a series of 20 orbits with periapses just outside Saturn's F ring that included some of the closest flybys of the tiny ring moons and excellent views of the F ring and outer A ring.Cassini's final close flyby of Titan in April 2017 propelled it across Saturn’s main rings and into its final orbits. Cassini's Grand Finale began in April 2017 and is comprised of 22 orbits at an inclination of 63 degrees. Cassini is repeatedly diving between the innermost ring and Saturn's upper atmosphere providing insights into fundamental questions unattainable during the rest of the mission. It is the first spacecraft to explore this region.These close orbits provide the highest resolution observations of both the rings and Saturn, and direct in situ sampling of the ring particles' composition, plasma, Saturn's exosphere and the innermost radiation belts. Saturn's gravitational field will be measured to unprecedented accuracy, providing information on Saturn's interior structure and mass distribution in the rings. Probing the magnetic field will give insight into the nature of the magnetic dynamo and the true rotation rate of Saturn's interior. The ion and neutral mass spectrometer will sniff the exosphere and upper atmosphere and examine water-based molecules originating from the rings. The cosmic dust analyzer will sample particle composition from different parts of the main rings.Recent science highlights and science objectives from Cassini’s final orbits will be discussed.This work was carried out in part at the Jet Propulsion Laboratory, California

  1. Two coiled-coil domains of Chlamydia trachomatis IncA affect membrane fusion events during infection.

    Directory of Open Access Journals (Sweden)

    Erik Ronzone

    Full Text Available Chlamydia trachomatis replicates in a parasitophorous membrane-bound compartment called an inclusion. The inclusions corrupt host vesicle trafficking networks to avoid the degradative endolysosomal pathway but promote fusion with each other in order to sustain higher bacterial loads in a process known as homotypic fusion. The Chlamydia protein IncA (Inclusion protein A appears to play central roles in both these processes as it participates to homotypic fusion and inhibits endocytic SNARE-mediated membrane fusion. How IncA selectively inhibits or activates membrane fusion remains poorly understood. In this study, we analyzed the spatial and molecular determinants of IncA's fusogenic and inhibitory functions. Using a cell-free membrane fusion assay, we found that inhibition of SNARE-mediated fusion requires IncA to be on the same membrane as the endocytic SNARE proteins. IncA displays two coiled-coil domains showing high homology with SNARE proteins. Domain swap and deletion experiments revealed that although both these domains are capable of independently inhibiting SNARE-mediated fusion, these two coiled-coil domains cooperate in mediating IncA multimerization and homotypic membrane interaction. Our results support the hypothesis that Chlamydia employs SNARE-like virulence factors that positively and negatively affect membrane fusion and promote infection.

  2. Two coiled-coil domains of Chlamydia trachomatis IncA affect membrane fusion events during infection.

    Science.gov (United States)

    Ronzone, Erik; Paumet, Fabienne

    2013-01-01

    Chlamydia trachomatis replicates in a parasitophorous membrane-bound compartment called an inclusion. The inclusions corrupt host vesicle trafficking networks to avoid the degradative endolysosomal pathway but promote fusion with each other in order to sustain higher bacterial loads in a process known as homotypic fusion. The Chlamydia protein IncA (Inclusion protein A) appears to play central roles in both these processes as it participates to homotypic fusion and inhibits endocytic SNARE-mediated membrane fusion. How IncA selectively inhibits or activates membrane fusion remains poorly understood. In this study, we analyzed the spatial and molecular determinants of IncA's fusogenic and inhibitory functions. Using a cell-free membrane fusion assay, we found that inhibition of SNARE-mediated fusion requires IncA to be on the same membrane as the endocytic SNARE proteins. IncA displays two coiled-coil domains showing high homology with SNARE proteins. Domain swap and deletion experiments revealed that although both these domains are capable of independently inhibiting SNARE-mediated fusion, these two coiled-coil domains cooperate in mediating IncA multimerization and homotypic membrane interaction. Our results support the hypothesis that Chlamydia employs SNARE-like virulence factors that positively and negatively affect membrane fusion and promote infection.

  3. A Decade of Cassini Radio Science so Far, and Three Spectacular Years Ahead

    Science.gov (United States)

    French, R. G.; Armstrong, J. W.; Flasar, F. M.; Iess, L.; Kliore, A. J.; Marouf, E. A.; McGhee-French, C.; Nagy, A. F.; Rappaport, N. J.; Schinder, P. J.; Tortora, P.; Anabtawi, A.; Asmar, S. W.; Barbinis, E.; Fleischman, D. U.; Kahan, D. S.

    2014-12-01

    Over the past decade, the Cassini RSS (Radio Science Subsystem) instrument has provided fundamental new insights into many aspects of the Saturn system. Taking advantage of the capability to use up to three simultaneous wavelengths (Ka, X, and S bands), a series of occultation experiments of Titan and Saturn have provided detailed vertical profiles of the atmospheric and ionospheric structure, exhibiting seasonal and regional variability. Gravity experiments, conducted during close flybys of Saturn's moons, have yielded information about their internal structure, including evidence of sub-surface oceans on Titan and Enceladus. From dozens of ring occultation experiements, the radial structure, scattering properties, and particle sizes of the rings have been measured to high precision, enabling detailed comparative studies of ring dynamics and orbital characteristics. Recent bistatic observations of Titan, in which the transmitted signal reflects off of the specular point and is received on Earth, have traversed the northern polar regions, crossing the boundaries between seas and land, showing that the surface of the seas is remarkably smooth, and providing information about the dielectric properties of the liquids and surface materials. The best is yet to come, during the final three years of the Cassini mission, when the RSS instrument will observe the rings in a series of occultation measurements at their most favorable geometry of the entire Cassini mission, and a companion set of close fly-bys of Saturn will provide the first detailed determination of Saturn's gravitational field.

  4. Production of 238PuO2 heat sources for the Cassini mission

    Science.gov (United States)

    George, Timothy G.; Foltyn, Elizabeth M.

    1998-01-01

    NASA's Cassini mission to Saturn, scheduled to launch in October, 1997, is perhaps the most ambitious interplanetary explorer ever constructed. Electric power for the spacecraft's science instruments and on-board computers will be provided by three radioisotope thermoelectric generators (RTGs) powered by 216 238PuO2-fueled General-Purpose Heat Source (GPHS) capsules. In addition, critical equipment and instruments on the spacecraft and Huygens probe will be warmed by 128 Light-Weight Radioisotope Heater Units (LWRHUs). Fabrication and assembly of the GPHS capsules and LWRHU heat sources was performed at Los Alamos National Laboratory (LANL) between January 1994 and September 1996. During this production campaign, LANL pressed and sintered 315 GPHS fuel pellets and 181 LWRHU pellets. By October 1996, NMT-9 had delivered a total of 235 GPHS capsules to EG&G Mound Applied Technologies (EG&G MAT) in Miamisburg, Ohio. EG&G MAT conditioned the capsules for use, loaded the capsules into the Cassini RTGs, tested the RTGs, and coordinated transportation to Kennedy Space Center (KSC). LANL also fabricated and assembled a total of 180 LWRHUs. The LWRHUs required for the Cassini spacecraft were shipped to KSC in mid-1997.

  5. On what we have learned about the system of Saturn thanks to Cassini

    Science.gov (United States)

    El Moutamid, Maryame; Hedman, Matthew M.; Nicholson, Philip D.; Tiscareno, Matthew S.; Tajeddine, Radwan; Burns, Joseph A.

    2017-06-01

    This is the end; Cassini will crash into Saturn’s atmosphere within few months, providing unique data and results thanks to the last orbits. After losing contact with us, it will become part of the planet itself.By September 2017, Cassini will have spent 13 years in orbit around Saturn, during this period, scientists from the world have collected data from many instruments and have learned a great deal about the planet itself, its rings and satellites, and the connection between them. I will present some of the results on what we have learned about the evolution of the moons, on the main rings of Saturn and their dynamical connection with the interior of the planet.

  6. Cusp observation at Saturn's high-latitude magnetosphere by the Cassini spacecraft

    Science.gov (United States)

    Jasinski, J. M.; Arridge, C. S.; Lamy, L.; Leisner, J. S.; Thomsen, M. F.; Mitchell, D. G.; Coates, A. J.; Radioti, A.; Jones, G. H.; Roussos, E.; Krupp, N.; Grodent, D.; Dougherty, M. K.; Waite, J. H.

    2014-03-01

    We report on the first analysis of magnetospheric cusp observations at Saturn by multiple in situ instruments onboard the Cassini spacecraft. Using this we infer the process of reconnection was occurring at Saturn's magnetopause. This agrees with remote observations that showed the associated auroral signatures of reconnection. Cassini crossed the northern cusp around noon local time along a poleward trajectory. The spacecraft observed ion energy-latitude dispersions—a characteristic signature of the terrestrial cusp. This ion dispersion is "stepped," which shows that the reconnection is pulsed. The ion energy-pitch angle dispersions suggest that the field-aligned distance from the cusp to the reconnection site varies between ˜27 and 51 RS. An intensification of lower frequencies of the Saturn kilometric radiation emissions suggests the prior arrival of a solar wind shock front, compressing the magnetosphere and providing more favorable conditions for magnetopause reconnection.

  7. Archaeological, radiological, and biological evidence offer insight into Inca child sacrifice.

    Science.gov (United States)

    Wilson, Andrew S; Brown, Emma L; Villa, Chiara; Lynnerup, Niels; Healey, Andrew; Ceruti, Maria Constanza; Reinhard, Johan; Previgliano, Carlos H; Araoz, Facundo Arias; Diez, Josefina Gonzalez; Taylor, Timothy

    2013-08-13

    Examination of three frozen bodies, a 13-y-old girl and a girl and boy aged 4 to 5 y, separately entombed near the Andean summit of Volcán Llullaillaco, Argentina, sheds new light on human sacrifice as a central part of the Imperial Inca capacocha rite, described by chroniclers writing after the Spanish conquest. The high-resolution diachronic data presented here, obtained directly from scalp hair, implies escalating coca and alcohol ingestion in the lead-up to death. These data, combined with archaeological and radiological evidence, deepen our understanding of the circumstances and context of final placement on the mountain top. We argue that the individuals were treated differently according to their age, status, and ritual role. Finally, we relate our findings to questions of consent, coercion, and/or compliance, and the controversial issues of ideological justification and strategies of social control and political legitimation pursued by the expansionist Inca state before European contact.

  8. Water quality improvements from afforestation in an agricultural catchment in Denmark illustrated with the INCA model

    DEFF Research Database (Denmark)

    Bastrup-Birk, A.; Gundersen, P.

    2004-01-01

    Intensive agricultural land use across Europe has altered nitrogen (N) budget of catchments substantially, causing widespread N pollution of freshwater. Although the N cycle in forests has changed due to increased N deposition, most forest soil waters in Europe have low nitrate concentrations....... The protective function of forests on water quality has led to increasing interest in the planting of new forests on arable land as a measure to protect valuable or sensitive freshwater resources. The paper illustrates the effects of afforestation on water and N cycling using the Integrated Nitrogen Catchment...... (INCA) model. The model was calibrated on the Horndrup catchment in the eastern part of Jutland, Denmark, which is dominated by agricultural land use but also covered by 18% of forest land. The dynamics of nitrate concentrations in the stream water were simulated successfully by INCA over a three...

  9. Inca Columbia Turbo平台式数码印刷机

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Inca Columbia Turbo超快速宽幅UV平台式数码印刷机是Inca与Sericol公司合作的杰出成果,它采用Spectra的高速喷墨头和富±色丽可公司的uvijetUV固化油墨,分辨力最高800dpl×1200dpi。Inca Columbia Turbo可以在厚度不超过40mm的刚性或柔性材料上印刷.印刷时喷墨头固定不动,承印材料移动,最大印刷面积1.6m×3.2m.印刷速度可达每小时160平方米。

  10. Archaeological, radiological, and biological evidence offer insight into Inca child sacrifice

    DEFF Research Database (Denmark)

    Wilson, Andrew S.; Brown, Emma L.; Villa, Chiara

    2013-01-01

    Examination of three frozen bodies, a 13-y-old girl and a girl and boy aged 4 to 5 y, separately entombed near the Andean summit of Volcán Llullaillaco, Argentina, sheds new light on human sacrifice as a central part of the Imperial Inca capacocha rite, described by chroniclers writing after...... of final placement on the mountain top. We argue that the individuals were treated differently according to their age, status, and ritual role. Finally, we relate our findings to questions of consent, coercion, and/or compliance, and the controversial issues of ideological justification and strategies...... of social control and political legitimation pursued by the expansionist Inca state before European contact....

  11. Cassini Radio and Plasma Wave Observations at Saturn

    Science.gov (United States)

    Gurnett, D. A.; Kurth, W. S.; Hospodarsky, G. B.; Persoon, A. M.; Averkamp, T. F.; Ceccni, B.; Lecacheux, A.; Zarka, P.; Canu, P.; Cornilleau-Wehrlin, N.

    2005-01-01

    Results are presented from the Cassini radio and plasma wave instrument during the approach and first few orbits around Saturn. During the approach the intensity modulation of Saturn Kilometric Radiation (SKR) showed that the radio rotation period of Saturn has increased to 10 hr 45 min plus or minus 36 sec, about 6 min longer than measured by Voyager in 1980-81. Also, many intense impulsive radio signals called Saturn Electrostatic Discharges (SEDs) were detected from saturnian lightning, starting as far as 1.08 AU from Saturn, much farther than terrestrial lightning can be detected from Earth. Some of the SED episodes have been linked to cloud systems observed in Saturn s atmosphere by the Cassini imaging system. Within the magnetosphere plasma wave emissions have been used to construct an electron density profile through the inner region of the magnetosphere. With decreasing radial distance the electron density increases gradually to a peak of about 100 per cubic centimeter near the outer edge of the A ring, and then drops precipitously to values as low as .03 per cubic centimeter over the rings. Numerous nearly monochromatic whistler-mode emissions were observed as the spacecraft passed over the rings that are believed to be produced by meteoroid impacts on the rings. Whistlermode emissions, similar to terrestrial auroral hiss were also observed over the rings, indicating that an electrodynamic interaction, similar to auroral particle acceleration, may be occurring in or near the rings. During the Titan flybys Langmuir probe and plasma wave measurements provided observations of the density and temperature in Titan's ionosphere.

  12. Cassini states for black-hole binaries

    CERN Document Server

    Correia, Alexandre C M

    2016-01-01

    Cassini states correspond to equilibria of the spin axis of a celestial body when its orbit is perturbed. They were initially described for planetary satellites, but the spin axes of black-hole binaries also present this kind of equilibria. In previous works, Cassini states were reported as spin-orbit resonances, but actually the spin of black-hole binaries is in circulation and there is no resonant motion. Here we provide a general description of the spin dynamics of black-hole binary systems based on a Hamiltonian formalism. In absence of dissipation the problem is integrable and it is easy to identify all possible trajectories for the spin for a given value of the total angular momentum. As the system collapses due to radiation reaction, the Cassini states are shifted to different positions, which modifies the dynamics around them. This is why the final spin distribution may differ from the initial one. Our method provides a simple way of predicting the distribution of the spin of black-hole binaries at th...

  13. Testing the INCA model in a small agricultural catchment in southern Finland

    Directory of Open Access Journals (Sweden)

    K. Granlund

    2004-01-01

    Full Text Available Nutrient leaching from agricultural production is still recognised as a major environmental problem in Finland. To estimate agricultural nitrogen loading under changing land-use and climate conditions, the Integrated Nitrogen Model for Catchments (INCA was applied in Savijoki, a small (15.4 km2 agricultural catchment, which represents the intensively cultivated areas in south-western Finland. Hydrological calibration and testing of the INCA model was first carried out in Savijoki during 1981–2000. In spite of heterogeneous soil and land-use conditions, INCA was able to reproduce the overall hydrological regime in the stream. The model was calibrated further in respect of nitrogen processes during 1995–2000. The model was able, reasonably well, to simulate the overall annual dynamics of the inorganic N concentrations in the stream water and the annual N export from the catchment. The average simulated NO3-N export was 550 kg N km–2 yr–1 and the observed one (constituting more than half of the annual total N export was 592 kg N km–2 yr–1. For NH4-N, the simulated export was somewhat higher than that measured but NH4-N was only 4% of the total N export. In spite of some underestimation of flow and N concentration during extreme hydrological conditions, the INCA model proved to be a useful tool for analysing flow pattern and inorganic nitrogen leaching in a small agricultural catchment, characterised by a rapid response to rainfall. Keywords: nitrogen, integrated modelling, hydrology, catchment, agriculture

  14. Modelling nitrogen dynamics and distributions in the River Tweed, Scotland: an application of the INCA model

    Directory of Open Access Journals (Sweden)

    H. P. Jarvie

    2002-01-01

    Full Text Available The INCA (Integrated Nitrogen in Catchments model was applied to the River Tweed in the Scottish Borders, a large-scale (4400km2, spatially heterogeneous catchment, draining a wide range of agricultural land-use types, and which contributes approximately 20% of UK river flows to the North Sea. The model was calibrated for the first four years' data record (1994 to 1997 and tested over the following three years (1998 to 2000. The model calibration and testing periods incorporated a high degree of variability in climatic conditions and river flows within the Tweed catchment. The ability of the INCA model to reproduce broad-scale spatial patterns and seasonal dynamics in river flows and nitrate concentrations suggests that the processes controlling first order variability in river water nitrate concentrations have been represented successfully within the model. The tendency of the model to overestimate summer/early autumn baseflow nitrate concentrations during dry years may be linked to the operation of aquatic plant uptake effects. It is, therefore, suggested that consideration be given to incorporating a spatially and temporally variable in-stream plant uptake term for the application of INCA to lowland eutrophic rivers. Scenarios to examine possible impacts of environmental change on nitrate concentrations on the Tweed are examined. These include the effects of (i implementing different recommendations for fertiliser use and land use change under the Nitrate Sensitive Areas (NSA Scheme and the Scottish Code of Good Agricultural Practice, (ii worst case scenario changes linked to a dramatic reduction in livestock numbers as a result of a crisis in UK livestock farming and (iii changes in atmospheric nitrogen deposition. Keywords: Nitrate, nitrogen, modelling, Tweed, INCA

  15. A calendar Quipu of the early 17th century and its relationship with the Inca astronomy

    CERN Document Server

    Laurencich-Minelli, Laura

    2008-01-01

    The so-called Miccinelli documents are a set of documents which were written by Jesuit scholars in Peru within the first half of the 17th century. Among such documents, one contains the depiction of a Quipu, that is, a device made out of cords of different nature and colors which, with the help of nodes, were used by the Incas for storing data. This Quipu is claimed by the author, Blas Valera, to be a reproduction of the Inca calendar of the year of the Spanish conquest. We give here a complete analysis of the astronomical events occurred in Cusco in that year, showing that they actually correspond closely to the data reported in the Quipu, and compare the calendrical information - such as the names and the rituals of each month - with those given by other documents, especially the Nuova Coronica by G. Poma de Ayala. The possible relevance of the document for the knowledge of the original Inca lore of the sky is discussed in details.

  16. Los incas representados (Lima – siglo XVIII: ¿Supervivencia o renacimiento?

    Directory of Open Access Journals (Sweden)

    Perissat, Karine

    2000-12-01

    Full Text Available At the beginning of the 18th Century the indigenous people of Lima were accorded permission to celebrate the Spanish kings in a segregated group. The criollo elites expected them to represent their old kings in the demostrations, thus taking part in the exaltation of the Peruvian history. The descriptions of the limeño festivities, which show that the costumes of the Incas in the masquerades were highly hibridisized and baroque, allow us to analyse the characteristics of the Inca renaissance in the 18th Century. The costume played a basic role in the rehabilitation of the old Peruvian kings in the Colonial society.

    Al principio del siglo XVIII, se les otorgó a los indios de Lima la posibilidad de festejar a los monarcas españoles en grupo aparte. De ellos se esperaba que representasen a sus antiguos monarcas en desfiles o mascaradas y participaran por consiguiente, animados por las elites criollas, en la exaltación de la historia peruana. Fuertemente mestizada y apropiada a los gustos barrocos, la indumentaria de los incas de las mascaradas descrita en las relaciones de fiestas limeñas nos permite analizar las características del renacimiento incaico del siglo XVIII y ver cómo la vestimenta desempañaba un papel fundamental en la rehabilitación de los antiguos monarcas peruanos en la sociedad colonial.

  17. Putting the rise of the Inca Empire within a climatic and land management context

    Science.gov (United States)

    Chepstow-Lusty, A. J.; Frogley, M. R.; Bauer, B. S.; Leng, M. J.; Boessenkool, K. P.; Carcaillet, C.; Ali, A. A.; Gioda, A.

    2009-07-01

    The rapid expansion of the Inca from the Cuzco area of highland Peru (ca. AD 1400-1532) produced the largest empire in the New World. Although this meteoric growth may in part be due to the adoption of innovative societal strategies, supported by a large labour force and a standing army, we argue that it would not have been possible without increased crop productivity, which was linked to more favourable climatic conditions. Here we present a multi-proxy, high-resolution 1200-year lake sediment record from Marcacocha, located 12 km north of Ollantaytambo, in the heartland of the Inca Empire. This record reveals a period of sustained aridity that began from AD 880, followed by increased warming from AD 1100 that lasted beyond the arrival of the Spanish in AD 1532. These increasingly warmer conditions would have allowed the Inca and their immediate predecessors the opportunity to exploit higher altitudes (post-AD 1150) by constructing agricultural terraces that employed glacial-fed irrigation, in combination with deliberate agroforestry techniques. There may be some important lessons to be learnt today from these strategies for sustainable rural development in the Andes in the light of future climate uncertainty.

  18. Putting the rise of the Inca Empire within a climatic and land management context

    Directory of Open Access Journals (Sweden)

    A. J. Chepstow-Lusty

    2009-03-01

    Full Text Available The rapid expansion of the Inca from the Cuzco area of highland Peru produced the largest empire in the New World between ca. AD 1400–1532. Although this meteoric rise may in part be due to the adoption of innovative societal strategies, supported by a large labour force and standing army, we argue that this would not have been possible without increased crop productivity, which was linked to more favourable climatic conditions. A multi-proxy, high-resolution 1200-year lake sediment record was analysed at Marcacocha, 12 km north of Ollantaytambo, in the heartland of the Inca Empire. This record reveals a period of sustained aridity that began from AD 880, followed by increased warming from AD 1100 that lasted beyond the arrival of the Spanish in AD 1532. These increasingly warmer conditions allowed the Inca and their predecessors the opportunity to exploit higher altitudes from AD 1150, by constructing agricultural terraces that employed glacial-fed irrigation, in combination with deliberate agroforestry techniques. There may be some important lessons to be learnt today from these strategies for sustainable rural development in the Andes in the light of future climate uncertainty.

  19. Identification and characterisation of coding tandem repeat variants in incA gene of Chlamydophila pecorum.

    Science.gov (United States)

    Yousef Mohamad, Khalil; Rekiki, Abdessalem; Myers, Garry; Bavoil, Patrik M; Rodolakis, Annie

    2008-01-01

    Bacteria of the family Chlamydiaceae are obligate intracellular pathogens of human and animals. Chlamydophila pecorum is associated with different pathological conditions in ruminants, swine and koala. To characterize a coding tandem repeat (CTR) identified at the 3' end of incA gene of C. pecorum, 51 strains of different chlamydial species were examined. The CTR were observed in 18 of 18 tested C. pecorum isolates including symptomatic and asymptomatic animals from diverse geographical origins. The CTR were also found in two strains of C. abortus respectively isolated from faeces from a healthy ewe and from a goat belonging to asymptomatic herds, but were absent in C. abortus strains isolated from clinical disease specimens, and in tested strains of C. psittaci, C. caviae, C. felis and C. trachomatis. The number of CTR repeats is variable and encode several motifs that are rich in alanine and proline. The CTR-derived variable structure of incA, which encode the Chlamydiaceae-specific type III secreted inclusion membrane protein, IncA, may be involved in the adaptation of C. pecorum to its environment by allowing it to persist in the host cell.

  20. Putting the rise of the Inca Empire within a climatic and land management context

    Directory of Open Access Journals (Sweden)

    A. J. Chepstow-Lusty

    2009-07-01

    Full Text Available The rapid expansion of the Inca from the Cuzco area of highland Peru (ca. AD 1400–1532 produced the largest empire in the New World. Although this meteoric growth may in part be due to the adoption of innovative societal strategies, supported by a large labour force and a standing army, we argue that it would not have been possible without increased crop productivity, which was linked to more favourable climatic conditions. Here we present a multi-proxy, high-resolution 1200-year lake sediment record from Marcacocha, located 12 km north of Ollantaytambo, in the heartland of the Inca Empire. This record reveals a period of sustained aridity that began from AD 880, followed by increased warming from AD 1100 that lasted beyond the arrival of the Spanish in AD 1532. These increasingly warmer conditions would have allowed the Inca and their immediate predecessors the opportunity to exploit higher altitudes (post-AD 1150 by constructing agricultural terraces that employed glacial-fed irrigation, in combination with deliberate agroforestry techniques. There may be some important lessons to be learnt today from these strategies for sustainable rural development in the Andes in the light of future climate uncertainty.

  1. The INCA system: a further step towards a telemedical artificial pancreas.

    Science.gov (United States)

    Gómez, Enrique J; Hernando Pérez, M Elena; Vering, Thomas; Rigla Cros, Mercedes; Bott, Oliver; García-Sáez, Gema; Pretschner, Peter; Brugués, Eulalia; Schnell, Oliver; Patte, Caroline; Bergmann, Joachim; Dudde, Ralf; de Leiva, Alberto

    2008-07-01

    Biomedical engineering research efforts have accomplished another level of a "technological solution" for diabetes: an artificial pancreas to be used by patients and supervised by healthcare professionals at any time and place. Reliability of continuous glucose monitoring, availability of real-time programmable insulin pumps, and validation of safe and efficient control algorithms are critical components for achieving that goal. Nevertheless, the development and integration of these new technologies within a telemedicine system can be the basis of a future artificial pancreas. This paper introduces the concept, design, and evaluation of the "intelligent control assistant for diabetes, INCA" system. INCA is a personal digital assistant (PDA)-based personal smart assistant to provide patients with closed-loop control strategies (personal and remote loop), based on a real-time continuous glucose sensor (Guardian RT, Medtronic), an insulin pump (D-TRON, Disetronic Medical Systems), and a mobile general packet radio service (GPRS)-based telemedicine communication system. Patient therapeutic decision making is supervised by doctors through a multiaccess telemedicine central server that provides to diabetics and doctors a Web-based access to continuous glucose monitoring and insulin infusion data. The INCA system has been technically and clinically evaluated in two randomized and crossover clinical trials showing an improvement on glycaemic control of diabetic patients.

  2. Ensuring Cassini's End-of-Mission Propellant Margins

    Science.gov (United States)

    Sturm, Erick J., II; Barber, Todd J.; Roth, Duane

    2015-01-01

    The Cassini spacecraft is in its final years. On September 15, 2017, Cassini will plunge deep into Saturn's atmosphere never to reemerge; thus concluding its second extended mission and 13 years in orbit around the ringed planet. As of October 2014, the spacecraft is four years in to its seven-year, second extended mission, the Cassini Solstice Mission (CSM). With three years left and only 2.5% of its loaded bipropellant and 37% of its loaded monopropellant remaining, the Cassini project actively manages the predicted end-of-mission propellant margins to maintain a high confidence in the spacecraft's ability to complete the CSM as designed.

  3. The architecture of the Cassini division

    Science.gov (United States)

    Hedman, M.M.; Nicholson, P.D.; Baines, K.H.; Buratti, B.J.; Sotin, Christophe; Clark, R.N.; Brown, R.H.; French, R.G.; Marouf, E.A.

    2010-01-01

    The Cassini Division in Saturn's rings contains a series of eight named gaps, three of which contain dense ringlets. Observations of stellar occultations by the Visual and Infrared Mapping Spectrometer onboard the Cassini spacecraft have yielded 40 accurate and precise measurements of the radial position of the edges of all of these gaps and ringlets. These data reveal suggestive patterns in the shapes of many of the gap edges: the outer edges of the five gaps without ringlets are circular to within 1 km, while the inner edges of six of the gaps are eccentric, with apsidal precession rates consistent with those expected for eccentric orbits near each edge. Intriguingly, the pattern speeds of these eccentric inner gap edges, together with that of the eccentric Huygens Ringlet, form a series with a characteristic spacing of 006 day-1. The two gaps with non-eccentric inner edges lie near first-order inner Lindblad resonances (ILRs) with moons. One such edge is close to the 5:4 ILR with Prometheus, and the radial excursions of this edge do appear to have an m = 5 component aligned with that moon. The other resonantly confined edge is the outer edge of the B ring, which lies near the 2:1 Mimas ILR. Detailed investigation of the B-ring-edge data confirm the presence of an m = 2 perturbation on the B-ring edge, but also show that during the course of the Cassini Mission, this pattern has drifted backward relative to Mimas. Comparisons with earlier occultation measurements going back to Voyager suggest the possibility that the m = 2 pattern is actually librating relative to Mimas with a libration frequency L 006 day-1 (or possibly 012 day -1). In addition to the m = 2 pattern, the B-ring edge also has an m = 1 component that rotates around the planet at a rate close to the expected apsidal precession rate (?? ?? ?? B ??? 5.??06 day -1). Thus, the pattern speeds of the eccentric edges in the Cassini Division can be generated from various combinations of the pattern speeds

  4. Cassini, Jean-Dominique [known as Cassini IV] (1748-1845)

    Science.gov (United States)

    Murdin, P.

    2000-11-01

    Astronomer, born at the Paris Observatory, great-grandson of the first director, grandson of the second, son of the third and himself the fourth, assuming the responsibilities of the directorship during the decline of his father, and the directorship itself in 1784. Persuaded King Louis XVI to restore the observatory, but the French Revolution occurred and Cassini, a monarchist, bitterly opposed ...

  5. Trends in food and nutritional intakes of French adults from 1999 to 2007: results from the INCA surveys.

    Science.gov (United States)

    Dubuisson, Carine; Lioret, Sandrine; Touvier, Mathilde; Dufour, Ariane; Calamassi-Tran, Gloria; Volatier, Jean-Luc; Lafay, Lionel

    2010-04-01

    Two independent cross-sectional dietary surveys (the Individual and National Food Consumption Surveys, INCA), performed in 1998-99 (INCA1) and in 2006-07 (INCA2) on nationally representative samples of French people, were used to analyse trends in the dietary habits and nutritional intake of French adults. Food consumption was recorded through 7-d dietary records, and nutritional intakes were assessed using the French food composition database. After exclusion of under-reporters, analyses were performed on 3267 adults, aged 18-79 years: 1345 from INCA1 and 1922 from INCA2. The trends highlighted over the 8-year period showed a decrease in consumption of dairy products, meat, bread, potatoes, pastries/croissant-like pastries/cakes/biscuits and sugar/confectionery. In contrast, the consumption of fruits and vegetables, rice, ice cream and chocolate increased. Other food groups, like fish and snacking foods, remained stable. Food choices were mostly age specific. These age differences remained consistent over the years and underlined two opposite dietary trends: a 'traditional' one mainly followed by the elderly, and a 'snacking and convenience' one mainly adopted by young adults. The overall trends in food consumption did not influence the mean energy intake, but did slightly modify the contribution of each macronutrient to energy intake. These repeated surveys highlighted the fact that trends in French food habits have moved towards an average European diet at the crossroads between Mediterranean and Northern diets, and that food consumption changes impacted, to a lesser extent, nutritional intake.

  6. Thermal Infrared Spectroscopy of Saturn and Titan from Cassini

    Science.gov (United States)

    Jennings, Donald E.; Brasunas, J. C.; Carlson, R. C.; Flasar, F. M.; Kunde, V. G.; Mamoutkine, A. A.; Nixon, A.; Pearl, J. C.; Romani, P. N.; Simon-Miller, A. A.; Bjoraker, G. L.

    2009-01-01

    The Cassini spacecraft completed its nominal mission at Saturn in 2008 and began its extended mission. Cassini carries the Composite Infrared Spectrometer (CIRS); a Fourier transform spectrometer that measures the composition, thermal structure and dynamics of the atmospheres of Saturn and Titan, and also the temperatures of other moons and the rings.

  7. Cassini capturing of freshly-produced water-group ions in the Enceladus torus

    Science.gov (United States)

    Yaroshenko, V. V.; Miloch, W. J.; Thomas, H. M.; Morfill, G. E.

    2012-09-01

    The water vapor plume on the geological-active south-polar region of the moon Enceladus is recognized as the main source of Saturn's neutral torus centered on the Enceladus orbit. The composition of the torus is dominated by water group species. Recent in situ Cassini plasma spectrometer measurements indicate the existence of freshly produced, slow and non-thermalized water group ions throughout the Enceladus torus including regions far from the moon. We report the results of modeling spacecraft-plasma interactions in the environment relevant for the Enceladus torus to show that new-born non-thermalized ions will inevitably be captured by the electric fields arising around the charged spacecraft. The associated plasma configuration can directly impact the plasma measurements and thus is important for reliable interpretation of data obtained by Cassini instruments in the Enceladus torus. The simulation results appear to be partially supported by Cassini observations and can provide new insights into intricate process of Enceladus-plasma interactions.

  8. Cassini Solstice Mission Maneuver Experience: Year Two

    Science.gov (United States)

    Arrieta, Juan; Ballard, Christopher G.; Hahn, Yungsun

    2012-01-01

    The Cassini Spacecraft was launched in October 1997 on a mission to observe Saturn and its moons; it entered orbit around Saturn in July 2004 for a nominal four-year Prime Mission, later augmented by two extensions: the Equinox Mission, from July 2008 through September 2010, and the Solstice Mission, from October 2010 through September 2017. This paper provides an overview of the maneuver activities from August 2011 through June 2012 which include the design of 38 Orbit Trim Maneuvers--OTM-288 through OTM-326-- for attaining 14 natural satellite encounters: seven with Titan, six with Enceladus, and one with Dione.

  9. The function of female and male ornaments in the Inca Tern: evidence for links between ornament expression and both adult condition and reproductive performance

    NARCIS (Netherlands)

    Velando, A.; Lessells, C.M.; Marquez, J.C.

    2001-01-01

    Inca Terns Larosterna inca are medium-size seabirds that breed along the Peruvian and Chilean coast. They are monogamous and both sexes incubate and contribute to chick provisioning. The sexes are similar in appearance and have elaborate ornaments, including a long white moustache of feathers and

  10. The function of female and male ornaments in the Inca Tern: evidence for links between ornament expression and both adult condition and reproductive performance

    NARCIS (Netherlands)

    Velando, A.; Lessells, C.M.; Marquez, J.C.

    2001-01-01

    Inca Terns Larosterna inca are medium-size seabirds that breed along the Peruvian and Chilean coast. They are monogamous and both sexes incubate and contribute to chick provisioning. The sexes are similar in appearance and have elaborate ornaments, including a long white moustache of feathers and fl

  11. The function of female and male ornaments in the Inca Tern: evidence for links between ornament expression and both adult condition and reproductive performance

    NARCIS (Netherlands)

    Velando, A.; Lessells, C.M.; Marquez, J.C.

    2001-01-01

    Inca Terns Larosterna inca are medium-size seabirds that breed along the Peruvian and Chilean coast. They are monogamous and both sexes incubate and contribute to chick provisioning. The sexes are similar in appearance and have elaborate ornaments, including a long white moustache of feathers and fl

  12. Inflight Performance of Cassini Reaction Wheel Bearing Drag in 1997-2013

    Science.gov (United States)

    Lee, Allan Y.; Wang, Eric K.

    2013-01-01

    As the first spacecraft to achieve orbit at Saturn in 2004, Cassini has collected science data throughout its four-year prime mission (2004-08), and has since been approved for a first and second extended missions through September 2017. Cassini is a three-axis stabilized spacecraft. It uses reaction wheels to achieve high level of spacecraft pointing stability that is needed during imaging operations of several science instruments. The Cassini flight software makes in-flight estimates of reaction wheel bearing drag torque and made them available to the mission operations team. These telemetry data are being trended for the purpose of monitoring the long-term health of the reaction wheel bearings. Anomalous drag torque signatures observed over the past 15 years are described in this paper. One of these anomalous drag conditions is bearing cage instability that appeared (and disappeared) spontaneously and unpredictably. Cage instability is an uncontrolled vibratory motion of the bearing cage that can produce high-impact forces internal to the bearing that will cause intermittent and erratic torque transients. Characteristics of the observed cage instabilities and other drag torque "spikes" are described in this paper. In day-to-day operations, the reaction wheels' rates must be neither too high nor too low. To protect against operating the wheels in any undesirable conditions (such as prolonged low spin rate operations), a ground software tool named Reaction Wheel Bias Optimization Tool (RBOT) was developed for the management of the wheels. Disciplined and long-term use of this ground software has led to significant reduction in the daily consumption rate of the wheels' low spin rate dwell time. Flight experience on the use of this ground software tool as well as other lessons learned on the management of Cassini reaction wheels is given in this paper.

  13. Enhancing Cassini Operations & Science Planning Tools

    Science.gov (United States)

    Castello, Jonathan

    2012-01-01

    The Cassini team uses a variety of software utilities as they manage and coordinate their mission to Saturn. Most of these tools have been unchanged for many years, and although stability is a virtue for long-lived space missions, there are some less-fragile tools that could greatly benefit from modern improvements. This report shall describe three such upgrades, including their architectural differences and their overall impact. Emphasis is placed on the motivation and rationale behind architectural choices rather than the final product, so as to illuminate the lessons learned and discoveries made.These three enhancements included developing a strategy for migrating Science Planning utilities to a new execution model, rewriting the team's internal portal for ease of use and maintenance, and developing a web-based agenda application for tracking the sequence of files being transmitted to the Cassini spacecraft. Of this set, the first two have been fully completed, while the agenda application is currently in the early prototype stage.

  14. The Architecture of the Cassini Division

    CERN Document Server

    Hedman, M M; Baines, K; Buratti, B; Sotin, C; Clark, R N; Brown, R H; French, R; Marouf, E

    2009-01-01

    The Cassini Division in Saturn's rings contains a series of eight named gaps, three of which contain dense ringlets. Observations of stellar occultations by the Visual and Infrared Mapping Spectrometer onboard the Cassini spacecraft have yielded ~40 accurate and precise measurements of the radial position of the edges of all of these gaps and ringlets. These data reveal suggestive patterns in the shapes of many of the gap edges: the outer edges of the 5 gaps without ringlets are circular to within 1 km, while the inner edges of 6 of the gaps are eccentric, with apsidal precession rates consistent with those expected for eccentric orbits near each edge. Intriguingly, the pattern speeds of these eccentric inner gap edges, together with that of the eccentric Huygens ringlet,form a series with a characteristic spacing of 0.06 degrees/day. The two gaps with non-eccentric inner edges lie near first-order Inner Lindblad Resonances (ILRs) with moons. One such edge is close to the 5:4 ILR with Prometheus. The other re...

  15. Cassini-Huygens results on Titan's surface

    Institute of Scientific and Technical Information of China (English)

    Athena Coustenis; Mathieu Hirtzig

    2009-01-01

    Our understanding of Titan, Saturn's largest satellite, has recently been consid-erably enhanced, thanks to the Cassini-Huygens mission. Since the Saturn Orbit Injection in July 2004, the probe has been harvesting new insights of the Kronian system. In par-ticular, this mission orchestrated a climax on January 14, 2005 with the descent of the Huygens probe into Titan's thick atmosphere. The orbiter and the lander have provided us with picturesque views of extraterrestrial landscapes, new in composition but reassuringly Earth-like in shape. Thus, Saturn's largest satellite displays chains of mountains, fields of dark and damp dunes, lakes and possibly geologic activity. As on Earth, landscapes on Titan are eroded and modeled by some alien hydrology: dendritic systems, hydrocarbon lakes, and methane clouds imply periods of heavy rainfalls, even though rain was never observed directly. Titan's surface also proved to be geologically active - today or in the recent past - given the small number of impact craters listed to date, as well as a few possible cryovolcanic features. We attempt hereafter a synthesis of the most significant results of the Cassini-Huygens endeavor, with emphasis on the surface.

  16. An assessment of the fine sediment dynamics in an upland river system: INCA-Sed modifications and implications for fisheries.

    Science.gov (United States)

    Lazar, Attila N; Butterfield, Dan; Futter, Martyn N; Rankinen, Katri; Thouvenot-Korppoo, Marie; Jarritt, Nick; Lawrence, Deborah S L; Wade, Andrew J; Whitehead, Paul G

    2010-05-15

    There is a need for better links between hydrology and ecology, specifically between landscapes and riverscapes to understand how processes and factors controlling the transport and storage of environmental pollution have affected or will affect the freshwater biota. Here we show how the INCA modelling framework, specifically INCA-Sed (the Integrated Catchments model for Sediments) can be used to link sediment delivery from the landscape to sediment changes in-stream. INCA-Sed is a dynamic, process-based, daily time step model. The first complete description of the equations used in the INCA-Sed software (version 1.9.11) is presented. This is followed by an application of INCA-Sed made to the River Lugg (1077 km(2)) in Wales. Excess suspended sediment can negatively affect salmonid health. The Lugg has a large and potentially threatened population of both Atlantic salmon (Salmo salar) and Brown Trout (Salmo trutta). With the exception of the extreme sediment transport processes, the model satisfactorily simulated both the hydrology and the sediment dynamics in the catchment. Model results indicate that diffuse soil loss is the most important sediment generation process in the catchment. In the River Lugg, the mean annual Guideline Standard for suspended sediment concentration, proposed by UKTAG, of 25 mg l(-1) is only slightly exceeded during the simulation period (1995-2000), indicating only minimal effect on the Atlantic salmon population. However, the daily time step simulation of INCA-Sed also allows the investigation of the critical spawning period. It shows that the sediment may have a significant negative effect on the fish population in years with high sediment runoff. It is proposed that the fine settled particles probably do not affect the salmonid egg incubation process, though suspended particles may damage the gills of fish and make the area unfavourable for spawning if the conditions do not improve. Copyright 2010 Elsevier B.V. All rights reserved.

  17. Dynamics of Saturn's great storm of 2010-2011 from Cassini ISS and RPWS

    CERN Document Server

    Sayanagi, Kunio M; Ewald, Shawn P; Fischer, Georg; Ingersoll, Andrew P; Kurth, William S; Muro, Gabriel D; Porco, Carolyn C; West, Robert A

    2016-01-01

    Saturn's quasi-periodic planet-encircling storms are the largest convecting outbursts in the Solar System. The last eruption was in 1990. A new eruption started in December 2010 and presented the first-ever opportunity to observe such episodic storms from a spacecraft in orbit around Saturn. Here, we analyze images acquired with the Cassini Imaging Science Subsystem (ISS), which captured the storm's birth, evolution and demise. In studying the end of the convective activity, we also analyze the Saturn Electrostatic Discharge (SED) signals detected by the Radio and Plasma Wave Science (RPWS) instrument. [...

  18. Cassini radio and plasma wave investigation: Data compression and scientific applications

    Science.gov (United States)

    Woolliscroft, L. J. C.; Farrell, W. M.; Alleyne, H. St. C.; Gurnett, D. A.; Kirchner, D. L.; Kurth, W. S.; Thompson, J. A.

    1993-01-01

    The Radio and Plasma Wave Science (RPWS) experiment being built for the Cassini spacecraft will study a wide range of plasma and radio wave phenomena in the magnetosphere of Saturn and will also make valuable measurements during the cruise phase and at other encounters. A feature of data from wave receivers is the capability of producing vastly more data than the spacecraft telemetry link is capable of transmitting back to the Earth. Thus, techniques of on-board data compression and data reduction are important. The RPWS instrument has one processor dedicated to data compression tasks.

  19. Cassini radio and plasma wave investigation - Data compression and scientific applications

    Science.gov (United States)

    Woolliscroft, L. J. C.; Farrell, W. M.; Alleyne, H. St. C.; Gurnett, D. A.; Kirchner, D. L.; Kurth, W. S.; Thompson, J. A.

    1993-01-01

    The Radio and Plasma Wave Science (RPWS) experiment being built for the Cassini spacecraft will study a wide range of plasma and radio wave phenomena in the magnetosphere of Saturn and will also make valuable measurements during the cruise phase and at other encounters. A feature of data from wave receivers is the capability of producing vastly more data than the spacecraft telemetry link is capable of transmitting back to the Earth. Thus, techniques of on-board data compression and data reduction are important. The RPWS instrument has one processor dedicated to data compression tasks.

  20. N fluxes in two nitrogen saturated forested catchments in Germany: dynamics and modelling with INCA

    Directory of Open Access Journals (Sweden)

    J.-J. Langusch

    2002-01-01

    Full Text Available The N cycle in forests of the temperate zone in Europe has been changed substantially by the impact of atmospheric N deposition. Here, the fluxes and concentrations of mineral N in throughfall, soil solution and runoff in two German catchments, receiving high N inputs are investigated to test the applicability of an Integrated Nitrogen Model for European Catchments (INCA to small forested catchments. The Lehstenbach catchment (419 ha is located in the German Fichtelgebirge (NO Bavaria, 690-871 m asl. and is stocked with Norway spruce (Picea abies (L. Karst. of different ages. The Steinkreuz catchment (55 ha with European beech (Fagus sylvatica L. as the dominant tree species is located in the Steigerwald (NW Bavaria, 400-460 m asl.. The mean annual N fluxes with throughfall were slightly higher at the Lehstenbach (24.6 kg N ha-1 than at the Steinkreuz (20.4 kg N ha-1. In both catchments the N fluxes in the soil are dominated by NO3. At Lehstenbach, the N output with seepage at 90 cm soil depth was similar to the N flux with throughfall. At Steinkreuz more than 50 % of the N deposited was retained in the upper soil horizons. In both catchments, the NO3 fluxes with runoff were lower than those with seepage. The average annual NO3 concentrations in runoff in both catchments were between 0.7 to 1.4 mg NO3-N L-1 and no temporal trend was observed. The N budgets at the catchment scale indicated similar amounts of N retention (Lehstenbach: 19 kg N ha-1yr-1 ; Steinkreuz: 17 kg N ha-1yr-1. The parameter settings of the INCA model were simplified to reduce the model complexity. In both catchments, the NO3 concentrations and fluxes in runoff were matched well by the model. The seasonal patterns with lower NO3 runoff concentrations in summer at the Lehstenbach catchment were replicated. INCA underestimated the increased N3 concentrations during short periods of rewetting in late autumn at the Steinkreuz catchment. The model will be a helpful tool for the

  1. Stable isotope and DNA evidence for ritual sequences in Inca child sacrifice

    Science.gov (United States)

    Wilson, Andrew S.; Taylor, Timothy; Ceruti, Maria Constanza; Chavez, Jose Antonio; Reinhard, Johan; Grimes, Vaughan; Meier-Augenstein, Wolfram; Cartmell, Larry; Stern, Ben; Richards, Michael P.; Worobey, Michael; Barnes, Ian; Gilbert, M. Thomas P.

    2007-01-01

    Four recently discovered frozen child mummies from two of the highest peaks in the south central Andes now yield tantalizing evidence of the preparatory stages leading to Inca ritual killing as represented by the unique capacocha rite. Our interdisciplinary study examined hair from the mummies to obtain detailed genetic and diachronic isotopic information. This approach has allowed us to reconstruct aspects of individual identity and diet, make inferences concerning social background, and gain insight on the hitherto unknown processes by which victims were selected, elevated in social status, prepared for a high-altitude pilgrimage, and killed. Such direct information amplifies, yet also partly contrasts with, Spanish historical accounts. PMID:17923675

  2. Water quality improvements from afforestation in an agricultural catchment in Denmark illustrated with the INCA model

    Directory of Open Access Journals (Sweden)

    A. Bastrup-Birk

    2004-01-01

    Full Text Available Intensive agricultural land use across Europe has altered nitrogen (N budget of catchments substantially, causing widespread N pollution of freshwater. Although the N cycle in forests has changed due to increased N deposition, most forest soil waters in Europe have low nitrate concentrations. The protective function of forests on water quality has led to increasing interest in the planting of new forests on arable land as a measure to protect valuable or sensitive freshwater resources. The paper illustrates the effects of afforestation on water and N cycling using the Integrated Nitrogen Catchment (INCA model. The model was calibrated on the Horndrup catchment in the eastern part of Jutland, Denmark, which is dominated by agricultural land use but also covered by 18% of forest land. The dynamics of nitrate concentrations in the stream water were simulated successfully by INCA over a three-year period. The simulation of the dynamics of nitrate concentrations in the soil water is closely linked to the simulation of the hydrological dynamics and especially to the rainfall. The best fit was achieved for both arable and forest land during the wettest year of the study period. The model was then used to simulate the effect of afforestation of a catchment dominated by agriculture on N fluxes with seepage and runoff. Scenarios of whole catchment conversion to forest were run, based on observations of evapotranspiration and N deposition from other Danish sites. The simulated conversion to mature forest reduced runoff by 30–45% and reduced the nitrate concentrations in the soil water by 50–70%. The simulated effect of afforestation on N leaching was an almost direct reflection of the change in the N input: substantial changes in the plant demand and soil N dynamics over the afforestation period were not simulated. To simulate the N dynamics over longer time-scales, appropriate for the study of afforestation, it is suggested that the INCA model be run

  3. Determining titan's spin state from cassini radar images

    Science.gov (United States)

    Stiles, B.W.; Kirk, R.L.; Lorenz, R.D.; Hensley, S.; Lee, E.; Ostro, S.J.; Allison, M.D.; Callahan, P.S.; Gim, Y.; Iess, L.; Del Marmo, P.P.; Hamilton, G.; Johnson, W.T.K.; West, R.D.

    2008-01-01

    For some 19 areas of Titan's surface, the Cassini RADAR instrument has obtained synthetic aperture radar (SAR) images during two different flybys. The time interval between flybys varies from several weeks to two years. We have used the apparent misregistration (by 10-30 km) of features between separate flybys to construct a refined model of Titan's spin state, estimating six parameters: north pole right ascension and declination, spin rate, and these quantities' first time derivatives We determine a pole location with right ascension of 39.48 degrees and declination of 83.43 degrees corresponding to a 0.3 degree obliquity. We determine the spin rate to be 22.5781 deg day -1 or 0.001 deg day-1 faster than the synchronous spin rate. Our estimated corrections to the pole and spin rate exceed their corresponding standard errors by factors of 80 and 8, respectively. We also found that the rate of change in the pole right ascension is -30 deg century-1, ten times faster than right ascension rate of change for the orbit normal. The spin rate is increasing at a rate of 0.05 deg day -1 per century. We observed no significant change in pole declination over the period for which we have data. Applying our pole correction reduces the feature misregistration from tens of km to 3 km. Applying the spin rate and derivative corrections further reduces the misregistration to 1.2 km. ?? 2008. The American Astronomical Society. All rights reserved.

  4. Trajectory Dispersion Control for the Cassini Grand Finale Mission

    Science.gov (United States)

    Wong, Mau; Hahn, Yungsun; Roth, Duane; Vaquero, Mar

    2015-01-01

    The Cassini Grand Finale Mission, which consists of 22 ballistic orbits, will begin on April 22, 2017 after the last targeted Titan flyby. It will end on September 15, 2017 when the spacecraft dives into Saturn's atmosphere and be permanently captured. High volumes of unique science data from various onboard instruments are expected from the mission. To ensure its success and facilitate science planning, the trajectory dispersion needs to be controlled below 250 km (root-mean-square spatial deviation at the 68th percentile level) for a few segments of trajectory in the mission. This paper reports the formulation and solution of this dispersion control problem. We consider various sources of uncertainties including flyby error, orbit determination error, maneuver execution error, thruster firing control error, and uncertainty in Saturn's atmospheric model. A non-linear Monte Carlo Trajectory Dispersion tool is developed and employed for the analysis. It is found that a total of three Orbit Trim Maneuvers with a 99% (Delta)V usage of less than 2 m/s will adequately control the trajectory.

  5. Silicates on Iapetus from Cassini's Composite Infrared Spectrometer

    CERN Document Server

    Young, Cindy L; Clark, Roger N; Spencer, John R; Jennings, Donald E; Hand, Kevin P; Poston, Michael J; Carlson, Robert W

    2015-01-01

    We present the first spectral features obtained from Cassini's Composite Infrared Spectrometer (CIRS) for any icy moon. The spectral region covered by CIRS focal planes (FP) 3 and 4 is rich in emissivity features, but previous studies at these wavelengths have been limited by low signal to noise ratios (S/Rs) for individual spectra. Our approach is to average CIRS FP3 spectra to increase the S/R and use emissivity spectra to constrain the composition of the dark material on Iapetus. We find an emissivity feature at ~855 cm-1 and a possible doublet at 660 and 690 cm-1 that do not correspond to any known instrument artifacts. We attribute the 855 cm-1 feature to fine-grained silicates, similar to those found in dust on Mars and in meteorites, which are nearly featureless at shorter wavelengths. Silicates on the dark terrains of Saturn's icy moons have been suspected for decades, but there have been no definitive detections until now. Serpentines reported in the literature at ambient temperature and pressure hav...

  6. Cassini CAPS Measurements of Thermal Ion Properties: An Update

    Science.gov (United States)

    Wilson, R. J.; Bagenal, F.; Delamere, P. A.

    2010-12-01

    Since the Wilson et al. [2008] paper on thermal ion properties in Saturn's inner equatorial magnetosphere there have been several advances in forward model techniques and instrument knowledge. These include: a) Improved CAPS (SNG) calibration values since 2008. While the previous fits to data are still valid, this efficiency adjustment has the effect of reducing the density values calculated from that fit. Compared to the previous calibration values, nOH+ and nH+ are ≈30% and ≈9% lower respectively. b) Robust error analysis on the forward model process to produce standard deviations for the fitted parameters. This also shows the expected dependences between various fitted parameters, such as Vφ and OH+ T⊥, inherent in the model. c) Utilization of real magnetic field data to forward model T⊥ and T\\par. Previously assumed magnetic field was in the -z direction. In addition, these improvements allow us to remove the constraint that Vz = 0, and the use of real magnetic field data allows us to analyze data farther from the equator. References Wilson, R. J., R. L. Tokar, M. G. Henderson, T. W. Hill, M. F. Thomsen, and D. H. Pontius (2008), Cassini plasma spectrometer thermal ion measurements in Saturn's inner magnetosphere,

  7. Cassini atmospheric chemistry mapper. Volume 1. Investigation and technical plan

    Science.gov (United States)

    Smith, William Hayden; Baines, Kevin Hays; Drossart, Pierre; Fegley, Bruce; Orton, Glenn; Noll, Keith; Reitsema, Harold; Bjoraker, Gordon L.

    1990-01-01

    The Cassini Atmospheric Chemistry Mapper (ACM) enables a broad range of atmospheric science investigations for Saturn and Titan by providing high spectral and spatial resolution mapping and occultation capabilities at 3 and 5 microns. ACM can directly address the major atmospheric science objectives for Saturn and for Titan, as defined by the Announcement of Opportunity, with pivotal diagnostic measurements not accessible to any other proposed Cassini instrument. ACM determines mixing ratios for atmospheric molecules from spectral line profiles for an important and extensive volume of the atmosphere of Saturn (and Jupiter). Spatial and vertical profiles of disequilibrium species abundances define Saturn's deep atmosphere, its chemistry, and its vertical transport phenomena. ACM spectral maps provide a unique means to interpret atmospheric conditions in the deep (approximately 1000 bar) atmosphere of Saturn. Deep chemistry and vertical transport is inferred from the vertical and horizontal distribution of a series of disequilibrium species. Solar occultations provide a method to bridge the altitude range in Saturn's (and Titan's) atmosphere that is not accessible to radio science, thermal infrared, and UV spectroscopy with temperature measurements to plus or minus 2K from the analysis of molecular line ratios and to attain an high sensitivity for low-abundance chemical species in the very large column densities that may be achieved during occultations for Saturn. For Titan, ACM solar occultations yield very well resolved (1/6 scale height) vertical mixing ratios column abundances for atmospheric molecular constituents. Occultations also provide for detecting abundant species very high in the upper atmosphere, while at greater depths, detecting the isotopes of C and O, constraining the production mechanisms, and/or sources for the above species. ACM measures the vertical and horizontal distribution of aerosols via their opacity at 3 microns and, particularly, at 5

  8. Frozen Mummies from Andean Mountaintop Shrines: Bioarchaeology and Ethnohistory of Inca Human Sacrifice.

    Science.gov (United States)

    Ceruti, Maria Constanza

    2015-01-01

    This study will focus on frozen mummies of sacrificial victims from mounts Llullaillaco (6739 m), Quehuar (6130 m), El Toro (6160 m), and the Aconcagua massif. These finds provide bioarchaeological data from mountaintop sites that has been recovered in scientifically controlled excavations in the northwest of Argentina, which was once part of the southern province of the Inca Empire. Numerous interdisciplinary studies have been conducted on the Llullaillaco mummies, including radiological evaluations by conventional X-rays and CT scans, which provided information about condition and pathology of the bones and internal organ, as well as dental studies oriented to the estimation of the ages of the three children at the time of death. Ancient DNA studies and hair analysis were also performed in cooperation with the George Mason University, the University of Bradford, and the Laboratory of Biological Anthropology at the University of Copenhagen. Ethnohistorical sources reveal interesting aspects related to the commemorative, expiatory, propitiatory, and dedicatory aspects of human sacrifice performed under Inca rule. The selection of the victims along with the procedures followed during the performance of the capacocha ceremony will be discussed, based on the bioarchaeological evidences from frozen mummies and the accounts recorded by the Spanish chroniclers.

  9. Mechanical analysis of the dry stone walls built by the Incas

    Science.gov (United States)

    Castro, Jaime; Vallejo, Luis E.; Estrada, Nicolas

    2017-06-01

    In this paper, the retaining walls in the agricultural terraces built by the Incas are analyzed from a mechanical point of view. In order to do so, ten different walls from the Lower Agricultural Sector of Machu Picchu, Perú, were selected using images from Google Street View and Google Earth Pro. Then, these walls were digitalized and their mechanical stability was evaluated. Firstly, it was found that these retaining walls are characterized by two distinctive features: disorder and a block size distribution with a large size span, i.e., the particle size varies from blocks that can be carried by one person to large blocks weighing several tons. Secondly, it was found that, thanks to the large span of the block size distribution, the factor of safety of the Inca retaining walls is remarkably close to those that are recommended in modern geotechnical design standards. This suggests that these structures were not only functional but also highly optimized, probably as a result of a careful trial and error procedure.

  10. Technical Note: Alternative in-stream denitrification equation for the INCA-N model

    Science.gov (United States)

    Etheridge, J. R.; Birgand, F.; Burchell, M. R., II; Lepistö, A.; Rankinen, K.; Granlund, K.

    2014-04-01

    The Integrated Catchment model for Nitrogen (INCA-N) is a semi-distributed, process based model that has been used to model the impacts of land use, climate, and land management changes on hydrology and nitrogen loading. An observed problem with the INCA-N model is reproducing low nitrate-nitrogen concentrations during the summer growing season in some catchments. In this study, the current equation used to simulate the rate of in-stream denitrification was replaced with an alternate equation that uses a mass transfer coefficient and the stream bottom area. The results of simulating in-stream denitrification using the two different methods were compared for a one year simulation period of the Yläneenjoki catchment in Finland. The alternate equation (Nash-Sutcliffe efficiency = 0.61) simulated concentrations during the periods of the growing season with the lowest flow that were closer to the observed concentrations than the current equation (Nash-Sutcliffe efficiency = 0.60), but the results were mixed during other portions of the year. The results of the calibration and validation of the model using the two equations show that the alternate equation will simulate lower nitrate-nitrogen concentrations during the growing season when compared to the current equation, but promote investigation into other errors in the model that may be causing inaccuracies in the modeled concentrations.

  11. Frozen Mummies from Andean Mountaintop Shrines: Bioarchaeology and Ethnohistory of Inca Human Sacrifice

    Directory of Open Access Journals (Sweden)

    Maria Constanza Ceruti

    2015-01-01

    Full Text Available This study will focus on frozen mummies of sacrificial victims from mounts Llullaillaco (6739 m, Quehuar (6130 m, El Toro (6160 m, and the Aconcagua massif. These finds provide bioarchaeological data from mountaintop sites that has been recovered in scientifically controlled excavations in the northwest of Argentina, which was once part of the southern province of the Inca Empire. Numerous interdisciplinary studies have been conducted on the Llullaillaco mummies, including radiological evaluations by conventional X-rays and CT scans, which provided information about condition and pathology of the bones and internal organ, as well as dental studies oriented to the estimation of the ages of the three children at the time of death. Ancient DNA studies and hair analysis were also performed in cooperation with the George Mason University, the University of Bradford, and the Laboratory of Biological Anthropology at the University of Copenhagen. Ethnohistorical sources reveal interesting aspects related to the commemorative, expiatory, propitiatory, and dedicatory aspects of human sacrifice performed under Inca rule. The selection of the victims along with the procedures followed during the performance of the capacocha ceremony will be discussed, based on the bioarchaeological evidences from frozen mummies and the accounts recorded by the Spanish chroniclers.

  12. Radio Telescopes Will Add to Cassini-Huygens Discoveries

    Science.gov (United States)

    2004-12-01

    accuracy. They expect to measure the probe's position within two-thirds of a mile (1 kilometer) at a distance of nearly 750 million miles. "That's like being able to sit in your back yard and watch the ball in a ping-pong game being played on the Moon," said Leonid Gurvits of JIVE. Both the JPL and JIVE teams will record the data collected by the radio telescopes and process it later. In the case of the Doppler measurements, some real-time information may be available, depending on the strength of the signal, but the scientists on this team also plan to do their detailed analysis on recorded data. The JPL team is utilizing special instrumentation from the Deep Space Network called Radio Science Receivers. One will be loaned to the GBT and another to the Parkes radio observatory. "This is the same instrument that allowed us to support the challenging communications during the landing of the Spirit and Opportunity Mars rovers as well as the Cassini Saturn Orbit Insertion when the received radio signal was very weak," said Sami Asmar, the JPL scientist responsible for the data recording. When the Galileo spacecraft's probe entered Jupiter's atmosphere in 1995, a JPL team used the NSF's Very Large Array (VLA) radio telescope in New Mexico to directly track the probe's signal. Adding the data from the VLA to that experiment dramatically improved the accuracy of the wind-speed measurements. "The Galileo probe gave us a surprise. Contrary to some predictions, we learned that Jupiter's winds got stronger as we went deeper into its atmosphere. That tells us that those deeper winds are not driven entirely by sunlight, but also by heat coming up from the planet's core. If we get lucky at Titan, we'll get surprises there, too," said Robert Preston, another JPL scientist. The Huygens probe is a spacecraft built by the European Space Agency (ESA). In addition to the NRAO telescopes, the JPL Doppler Wind Experiment will use the Australia Telescope National Facility and other radio

  13. How Mimas cleared the Cassini Division

    Science.gov (United States)

    Noyelles, Benoit; Baillie, Kevin; Lainey, Valery; Charnoz, Sebastien

    2016-10-01

    Recent measurements of the dissipation of Saturn (Lainey et al. 2016, Icarus, in press) combined with a theoretical study by Fuller et al. (2016, MNRAS) require to revisit the energy dissipation models in planetary systems and the way it affects their satellite system. In addition, the measurements of the large librations of Mimas (Tajeddine et al. 2014, Science) could point to a global ocean underneath the surface of the satellite. These results allowed us to refine the scenarios of the opening of the Cassini Division that we initially presented at the DPS 2012. Assuming a dissipation that is consistent with these latest results, we propose scenarios of combined evolutions of Mimas and the main rings of Saturn, that explain the current size and location of the Division, the excess of density in the outer B ring, a past episode of intense heating of Mimas required to create a global ocean, and its current eccentricity. For that, we show that a past resonance with Tethys increased the eccentricity of Mimas up to 0.2, possibly triggering the melting of Mimas and an episode of inward migration, which created the Cassini Division: the 2:1 resonance between Mimas and the rings pushed the ring material inner to accumulate in the B ring. Once its eccentricity is damped, Mimas resumes its outward migration, leading to a trapping into the current vertical resonance with Tethys. These results are supported by numerical simulations, in which Mimas is driven by the tides, and the rings are simulated with the 1-D hydrodynamical code Hydrorings (Charnoz et al., 2010, Nature). This study has been partially supported by the International Space Sciences Institute in Bern, Switzerland.

  14. Titan's Isotopic Menagerie: The Cassini CIRS Perspective

    Science.gov (United States)

    Nixon, Conor A.; Achterberg, R. K.; Bezard, B.; Bjoraker, G. L.; Coustenis, A.; de Kok, R.; Flasar, F. M.; Hewagama, T.; Irwin, P. G. J.; Jennings, D. E.; Jolly, A.; Romani, P. N.; Teanby, N. A.; Vinatier, S.; CIRS Team

    2008-09-01

    Saturn's long-mysterious moon Titan is gradually yielding up its secrets under the intense scrutiny of the Cassini spacecraft, which has just completed a 4-year prime mission including 45 close flybys of the giant satellite. We here focus on the isotopic composition of the stratosphere, which since Voyager 1 in 1980 has been known to comprise a surprisingly rich mixture of hydrocarbons, nitriles and several oxygen species. These molecules are now understood to originate in the upper atmosphere by chemical processes initiated by the dissociation of the most abundant native species - methane and nitrogen - with some oxygen added from externally-supplied water. Measurements of isotopic ratios in these compounds are important and can provide valuable information on the formation and evolution of Titan's atmosphere. E.g. Chemical processes can cause isotopic fractionation via the 'kinetic isotope effect' (KIE). Cassini's Composite Infrared Spectrometer (CIRS), which is sensitive to thermal infrared radiation from 10-1500 cm-1 (7-1000 micron), is an ideal tool for measuring molecular concentrations and can distinguish between isotopologues due to the shifts in the molecular bands. CIRS has now identified at least eleven isotopologue species in our spectra, with multiple new detections in the past year (13CO2, CO18O, HC13CCCN). CIRS has measured the ratios 12C/13C in a total of seven species, D/H in two species, and 14N/15N and 16O/18O each in one species - the best measurement so far of the important ratio 16O/18O on Titan (346±110). In this presentation we will summarize all our results to date on isotopic ratios, including comparison with Huygens GCMS and other determinations, a discussion of possible isotopic separation in hydrocarbon chains, and formation/evolution implications of these measurements for Titan.

  15. Cassini Radio Occultation by Enceladus Plume

    Science.gov (United States)

    Kliore, A.; Armstrong, J.; Flasar, F.; French, R.; Marouf, E.; Nagy, A.; Rappaport, N.; McGhee, C.; Schinder, P.; Anabtawi, A.; Asmar, S.; Barbinis, E.; Fleischman, D.; Goltz, G.; Aguilar, R.; Rochblatt, D.

    2006-12-01

    A fortuitous Cassini radio occultation by Enceladus plume occurs on September 15, 2006. The occultation track (the spacecraft trajectory in the plane of the sky as viewed from the Earth) has been designed to pass behind the plume (to pass above the south polar region of Enceladus) in a roughly symmetrical geometry centered on a minimum altitude above the surface of about 20 km. The minimum altitude was selected primarily to ensure probing much of the plume with good confidence given the uncertainty in the spacecraft trajectory. Three nearly-pure sinusoidal signals of 0.94, 3.6, and 13 cm-wavelength (Ka-, X-, and S-band, respectively) are simultaneously transmitted from Cassini and are monitored at two 34-m Earth receiving stations of the Deep Space Network (DSN) in Madrid, Spain (DSS-55 and DSS-65). The occultation of the visible plume is extremely fast, lasting less than about two minutes. The actual observation time extends over a much longer time interval, however, to provide a good reference baseline for potential detection of signal perturbations introduced by the tenuous neutral and ionized plume environment. Given the likely very small fraction of optical depth due to neutral particles of sizes larger than about 1 mm, detectable changes in signal intensity is perhaps unlikely. Detection of plume plasma along the radio path as perturbations in the signals frequency/phase is more likely and the magnitude will depend on the electron columnar density probed. The occultation time occurs not far from solar conjunction time (Sun-Earth-probe angle of about 33 degrees), causing phase scintillations due to the solar wind to be the primary limiting noise source. We estimate a delectability limit of about 1 to 3E16 electrons per square meter columnar density assuming about 100 seconds integration time. Potential measurement of the profile of electron columnar density along the occultation track is an exciting prospect at this time.

  16. Machu Picchu: problemas de conservación de un sitio inca de ceja de selva

    Directory of Open Access Journals (Sweden)

    1992-01-01

    Full Text Available MACHU PICCHU: PROBLÈMES DE CONSERVATION D’UN SITE INCA DU PIEDMONT AMAZONIEN. Cet article présente la synthèse des diverses études (géomorphologie, géologie et conservation de l’architecture du site inca de Machu Picchu. Ces études ont mis en évidence les principaux facteurs de détérioration qui sont dus aux divers effets de l’eau sur l’architecture et sur le milieu environnant. La croissance de la végétation naturelle représente aussi un important facteur de détérioration qui vient s’ajouter aux effets néfastes des pluies très abondantes. Diverses mesures de protection peuvent aider à contrôler ces détériorations. D’autres facteurs, comme l’arrivée assez récente d’une végétation non autochtone et l’affluence d’un trop grand nombre de visiteurs, constituent des menaces supplémentaires. La protection du principal site archéologique et touristique du Pérou est toutefois possible en prenant des mesures adéquates contre ces agressions pour réduire autant que possible les détérioratons observées. Se presenta una síntesis de los diversos estudios (geomorfología, geología y conservación de la arquitectura realizados en el sitio inca de Machu Picchu. Estos estudios han puesto en evidencia los principales factores de deterioro que se deben a los diversos efectos del agua sobre la arquitectura y sobre el entorno. También, el desarrollo importante de la vegetación natural representa otro factor de deterioro, que se suma a los efectos nefastos del agua. Varias medidas de protección podrían mejorar el control de estos deterioros. Otros factores, tales como el crecimiento de una vegetación alógena o como la llegada de visitantes demasiado numerosos, constituyen amenazas suplementarias. Sin embargo, el principal sitio arqueológico y turístico del Perú se puede conservar con medidas adecuadas que permitirían reducir los deterioros, logrando una notable mejora de la situación actual. MACHU PICCHU

  17. Precision Pointing Reconstruction and Geometric Metadata Generation for Cassini Images

    Science.gov (United States)

    French, R. S.; Showalter, M. R.; Gordon, M. K.

    2017-06-01

    We are reconstructing accurate pointing for 400,000 images taken by Cassini at Saturn. The results will be provided to the public along with per-pixel metadata describing precise image contents such as geographical location and viewing geometry.

  18. Cassini Discovers a Kinematic Spiral Ring around Saturn

    National Research Council Canada - National Science Library

    S. Charnoz; C. C. Porco; E. Déau; A. Brahic; J. N. Spitale; C. Bacques; K. Baillie

    2005-01-01

    .... New Cassini observations show that these strands, initially interpreted as concentric ring segments, are in fact connected and form a single one-arm trailing spiral winding at least three times around Saturn...

  19. Mathematical Contributions of the Mayas, Aztecs & Incas: A Native American Curriculum Unit for Middle and High School. NATAM XIX.

    Science.gov (United States)

    Stodola, Janet

    Written to fulfill the requirements for a University of Minnesota College of Education off-campus Indian education course for public school teachers, this Native American curriculum unit for middle and high school reflects the mathematical achievements of the Maya, Aztec, and Inca Indians. The number systems, notation, and calendar techniques of…

  20. Cassini CAPS-ELS observations of carbon-based anions and aerosol growth in Titan's ionosphere

    Science.gov (United States)

    Desai, Ravindra; Coates, Andrew; Wellbrock, Anne; Kataria, Dhiren; Jones, Geraint; Lewis, Gethyn; Waite, J.

    2016-06-01

    Cassini observations of Titans ionosphere revealed an atmosphere rich in positively charged ions with masses up to > 350 amu and negatively charged ions and aerosols with mass over charge ratios as high as 13,800 amu/q. The detection of negatively charged molecules by the Cassini CAPS Electron Spectrometer (CAPS-ELS) was particularly surprising and showed how the synthesis of large aerosol-size particles takes place at altitudes much greater than previously thought. Here, we present further analysis into this CAPS-ELS dataset, through an enhanced understanding of the instrument's response function. In previous studies the intrinsic E/E energy resolution of the instrument did not allow specific species to be identified and the detections were classified into broad mass ranges. In this study we use an updated fitting procedure to show how the ELS mass spectrum can be resolved into specific peaks at multiples of carbon-based anions up to > 100 amu/q. The negatively charged ions and aerosols in Titans ionosphere increase in mass with decreasing altitude, the lightest species being observed close to Titan's exobase of ˜1,450km and heaviest species observed at altitudes < 950km. We identify key stages in this apparent growth process and report on key intermediaries which appear to trigger the rapid growth of the larger aerosol-size particles.

  1. An atlas of bright star spectra in the near infrared from Cassini-VIMS

    CERN Document Server

    Stewart, Paul N; Nicholson, Philip D; Sloan, G C; Hedman, Matthew M

    2015-01-01

    We present the Cassini Atlas Of Stellar Spectra (CAOSS), comprised of near-infrared low-resolution spectra of bright stars recovered from space-based observations by the Cassini spacecraft. The 65 stellar targets in the atlas are predominately M, K and S giants. However it also contains spectra of other bright nearby stars including carbon stars and main sequence stars from A to F. The spectra presented are free of all spectral contamination caused by the Earth's atmosphere, including the detrimental telluric molecular bands which put parts of the near-infrared spectrum out of reach of terrestrial observations. With a single instrument, a spectro-photometric dataset is recovered that spans the near-infrared from 0.8 to 5.1 microns with spectral resolution ranging from R=53.5 to R=325. Spectra have been calibrated into absolute flux units after careful characterisation of the instrumental spectral efficiency. Spectral energy distributions for most stars match closely with literature values. All final data prod...

  2. AN ATLAS OF BRIGHT STAR SPECTRA IN THE NEAR-INFRARED FROM CASSINI-VIMS

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, Paul N.; Tuthill, Peter G. [Sydney Institute for Astronomy, School of Physics, The University of Sydney, NSW 2006 (Australia); Nicholson, Philip D. [Department of Astronomy, Cornell University, Ithaca, NY 14853 (United States); Sloan, G. C. [Cornell Center for Astrophyics and Planetary Science, Cornell University, Ithaca, NY 14853 (United States); Hedman, Matthew M., E-mail: p.stewart@physics.usyd.edu.au [Department of Physics, University of Idaho, Moscow, ID 83844 (United States)

    2015-12-15

    We present the Cassini Atlas Of Stellar Spectra (CAOSS), comprised of near-infrared, low-resolution spectra of bright stars recovered from space-based observations by the Cassini spacecraft. The 65 stellar targets in the atlas are predominately M, K, and S giants. However, it also contains spectra of other bright nearby stars including carbon stars and main-sequence stars from A to F. The spectra presented are free of all spectral contamination caused by the Earth's atmosphere, including the detrimental telluric molecular bands which put parts of the near-infrared spectrum out of reach of terrestrial observations. With a single instrument, a spectro-photometric data set is recovered that spans the near-infrared from 0.8 to 5.1 μm with spectral resolution ranging from R = 53.5 to R = 325. Spectra have been calibrated into absolute flux units after careful characterization of the instrumental spectral efficiency. Spectral energy distributions for most stars match closely with literature values. All final data products have been made available online.

  3. Identidad y alteridad. La condición mestiza y la concepción histórica del Inca Garcilaso

    Directory of Open Access Journals (Sweden)

    Liliana Regalado de Hurtado

    2009-12-01

    Full Text Available Se examina la identidad que el Inca Garcilaso plantea en sus textos a partir de las nociones identidad, alteridad (Levinas y enunciado humano (Bajtín, así como de investigaciones en torno al Inca (Mazzotti 1996, Rodriguez Garrido 1993, Zanelli 1999. Esos conceptos y reflexiones se matizan y complementan desde la perspectiva histórica, en particular, con una aproximación a la concepción que el Inca Garcilaso tenía de la historia, un elemento indispensable para entender la construcción de la identidad mestiza del cronista.

  4. Long-term modelling of nitrogen turnover and critical loads in a forested catchment using the INCA model

    Directory of Open Access Journals (Sweden)

    J.-J. Langusch

    2002-01-01

    Full Text Available Many forest ecosystems in Central Europe have reached the status of N saturation due to chronically high N deposition. In consequence, the NO3 leaching into ground- and surface waters is often substantial. Critical loads have been defined to abate the negative consequences of the NO3 leaching such as soil acidification and nutrient losses. The steady state mass balance method is normally used to calculate critical loads for N deposition in forest ecosystems. However, the steady state mass balance approach is limited because it does not take into account hydrology and the time until the steady state is reached. The aim of this study was to test the suitability of another approach: the dynamic model INCA (Integrated Nitrogen Model for European Catchments. Long-term effects of changing N deposition and critical loads for N were simulated using INCA for the Lehstenbach spruce catchment (Fichtelgebirge, NE Bavaria, Germany under different hydrological conditions. Long-term scenarios of either increasing or decreasing N deposition indicated that, in this catchment, the response of nitrate concentrations in runoff to changing N deposition is buffered by a large groundwater reservoir. The critical load simulated by the INCA model with respect to a nitrate concentration of 0.4 mg N l–1 as threshold value in runoff was 9.7 kg N ha–1yr–1 compared to 10 kg ha–1yr–1 for the steady state model. Under conditions of lower precipitation (520 mm the resulting critical load was 7.7 kg N ha–1yr–1 , suggesting the necessity to account for different hydrological conditions when calculating critical loads. The INCA model seems to be suitable to calculate critical loads for N in forested catchments under varying hydrological conditions e.g. as a consequence of climate change. Keywords: forest ecosystem, N saturation, critical load, modelling, long-term scenario, nitrate leaching, critical loads reduction, INCA

  5. Functional interaction between type III-secreted protein IncA of Chlamydophila psittaci and human G3BP1.

    Science.gov (United States)

    Borth, Nicole; Litsche, Katrin; Franke, Claudia; Sachse, Konrad; Saluz, Hans Peter; Hänel, Frank

    2011-01-31

    Chlamydophila (Cp.) psittaci, the causative agent of psittacosis in birds and humans, is the most important zoonotic pathogen of the family Chlamydiaceae. These obligate intracellular bacteria are distinguished by a unique biphasic developmental cycle, which includes proliferation in a membrane-bound compartment termed inclusion. All Chlamydiaceae spp. possess a coding capacity for core components of a Type III secretion apparatus, which mediates specific delivery of anti-host effector proteins either into the chlamydial inclusion membrane or into the cytoplasm of target eukaryotic cells. Here we describe the interaction between Type III-secreted protein IncA of Cp. psittaci and host protein G3BP1 in a yeast two-hybrid system. In GST-pull down and co-immunoprecipitation experiments both in vitro and in vivo interaction between full-length IncA and G3BP1 were shown. Using fluorescence microscopy, the localization of G3BP1 near the inclusion membrane of Cp. psittaci-infected Hep-2 cells was demonstrated. Notably, infection of Hep-2 cells with Cp. psittaci and overexpression of IncA in HEK293 cells led to a decrease in c-Myc protein concentration. This effect could be ascribed to the interaction between IncA and G3BP1 since overexpression of an IncA mutant construct disabled to interact with G3BP1 failed to reduce c-Myc concentration. We hypothesize that lowering the host cell c-Myc protein concentration may be part of a strategy employed by Cp. psittaci to avoid apoptosis and scale down host cell proliferation.

  6. The INCA-Pathogens model: An application to the Loimijoki River basin in Finland.

    Science.gov (United States)

    Rankinen, K; Butterfield, D; Faneca Sànchez, M; Grizzetti, B; Whitehead, P; Pitkänen, T; Uusi-Kämppä, J; Leckie, H

    2016-12-01

    Good hygienic quality of surface waters is essential for drinking water production, irrigation of crops and recreation. Predictions of how and when microbes are transported by rivers are needed to protect downstream water users. In this study we tested the new process-based INCA-Pathogens model in the agricultural Loimijoki River basin (3138km(2)) in Finland, and we quantified ecosystem services of water purification and water provisioning for drinking and recreation purposes under different scenarios. INCA is a catchment scale process based model to calculate pollutant transfer from terrestrial environment and point sources to the catchment outlet. A clear gradient was observed in the numbers of faecal coliforms along the River Loimijoki. The highest bacterial counts were detected in the middle part of the main stream immediately after small industries and municipal sewage treatment plants. In terms of model performance, the INCA-Pathogen model was able to produce faecal coliform counts and seasonality both in the low pollution level sampling points and in the high pollution level sampling points. The model was sensitive to the parameters defining light decay in river water and in soil compartment, as well as to the amount of faecal coliforms in the manure spread on the fields. The modeling results showed that the number of faecal coliforms repeatedly exceeded 1000 bacteria 100ml(-1). Moreover, results lead to the following conclusions: 1) Climate change does not cause a major threat to hygienic water quality as higher precipitation increases runoff and causes diluting effect in the river, 2) Intensification of agriculture is not a threat as long as animal density remains relatively low and environmental legislation is followed, 3) More intensive agriculture without environmental legislation causes a threat especially in tributaries with high field percentage and animal density, and 4) Hygienic water quality in the River Loimijoki can best be improved by improving

  7. The Saturn System Through the Eyes of Cassini

    Science.gov (United States)

    Green, James

    2017-01-01

    More than 400 years ago, Galileo Galilei trained his homemade telescope on the night sky and observed that Saturn had two objects closely related to the planet extending on either side. At the time, in 1610, Galileo declared them to be moons. A few decades later, Saturn moon science accelerated at a dizzying pace. Christiaan Huygens first observed Saturn's largest moon Titan in 1655 and was the first to describe the extended moon-like features at Saturn as a disk of material sounding the planet. From 1671 to 1674, Giovanni Cassini discovered the moons lapetus, Rhea, Dione and Tethys. In 1675, Cassini discovered the gap in Saturn's rings that we now know as the Cassini Division. In the space age, before the Cassini-Huygens mission, we had only hints of the discoveries awaiting us at Saturn. Pioneer 11 and Voyagers 1 and 2 conducted flybys decades ago. But these quick encounters didn't allow time for more extensive research. NASA and the European Space Agency created a partnership to orbit a Saturn orbiter (Cassini) and a lander (Huygens) on Titan. Like its namesakes, the Cassini-Huygens mission not only discovered previously unknown moons, but it also helped us understand the science behind their formation, their interactions with the rings, and how truly diverse they are. The Cassini-Huygens mission revolutionized what we know about the Saturn system. The rings of Saturn, the moons, and the planet itself offer irresistible and inexhaustible subjects for intense study, and Cassini-Huygens did not disappoint. The Saturnian system proved to be a rich ground for science exploration and discoveries, and Cassini has been nothing short of a discovery machine. At the time Cassini plunged into Saturn at the end of its mission, it had observed the planet for a little less than half of a Saturn year. But it also orbited the gas giant 293 times, forever changing our understanding of the Saturn system and yielding tremendous insight for understanding the entire Solar System.

  8. Near-infrared spectra of liquid/solid acetylene under Titan relevant conditions and implications for Cassini/VIMS detections

    Science.gov (United States)

    Singh, S.; Cornet, T.; Chevrier, V. F.; Combe, J.-Ph.; McCord, T. B.; Roe, L. A.; Le Mouélic, S.; Le Menn, E.; Wasiak, F. C.

    2016-05-01

    Acetylene is thought to be abundant on Titan according to most photochemical models. While detected in the atmosphere, its likely presence at the surface still lacks physical evidence. It is thought that solid acetylene could be a major component of Titan's lakes shorelines and dry lakebed, detected as the 5 μm-bright deposits with the Cassini/VIMS instrument. Acetylene could also be present under its liquid form as dissolved solids in Titan's methane-ethane lakes, as emphasized by thermodynamics studies. This paper is devoted to the near-infrared spectroscopy study of acetylene under solid and liquid phases between 1 and 2.2 μm, synthesized in a Titan simulation chamber that is able to reproduce extreme temperature conditions. From experiments, we observed a ∼10% albedo increase between liquid acetylene at 193-188 K and solid acetylene at 93 K. Using the NIR spectroscopy technique we successfully calculated the reflectivity ratio of solid/liquid acetylene as 1.13. The second difference we observed between liquid and solid acetylene is a shift in the major absorption band detected at 1.54 μm, the shift of ∼0.01 μm occurring toward higher wavelength. In order to assess the detectability of acetylene on Titan using the Cassini/VIMS instrument, we adapted our spectra to the VIMS spectral resolution. The spectral band at 1.55 μm and a negative slope at 2.0 μm falls in the Cassini/VIMS atmospheric windows over several VIMS infrared spectels, thus Cassini/VIMS should be able to detect acetylene.

  9. The cosmic dust analyser onboard cassini: ten years of discoveries

    Science.gov (United States)

    Srama, R.; Kempf, S.; Moragas-Klostermeyer, G.; Altobelli, N.; Auer, S.; Beckmann, U.; Bugiel, S.; Burton, M.; Economomou, T.; Fechtig, H.; Fiege, K.; Green, S. F.; Grande, M.; Havnes, O.; Hillier, J. K.; Helfert, S.; Horanyi, M.; Hsu, S.; Igenbergs, E.; Jessberger, E. K.; Johnson, T. V.; Khalisi, E.; Krüger, H.; Matt, G.; Mocker, A.; Lamy, P.; Linkert, G.; Lura, F.; Möhlmann, D.; Morfill, G. E.; Otto, K.; Postberg, F.; Roy, M.; Schmidt, J.; Schwehm, G. H.; Spahn, F.; Sterken, V.; Svestka, J.; Tschernjawski, V.; Grün, E.; Röser, H.-P.

    2011-12-01

    The interplanetary space probe Cassini/Huygens reached Saturn in July 2004 after 7 years of cruise phase. The German cosmic dust analyser (CDA) was developed under the leadership of the Max Planck Institute for Nuclear Physics in Heidelberg under the support of the DLR e.V. This instrument measures the interplanetary, interstellar and planetary dust in our solar system since 1999 and provided unique discoveries. In 1999, CDA detected interstellar dust in the inner solar system followed by the detection of electrical charges of interplanetary dust grains during the cruise phase between Earth and Jupiter. The instrument determined the composition of interplanetary dust and the nanometre-sized dust streams originating from Jupiter's moon Io. During the approach to Saturn in 2004, similar streams of submicron grains with speeds in the order of 100 km/s were detected from Saturn's inner and outer ring system and are released to the interplanetary magnetic field. Since 2004 CDA measured more than one million dust impacts characterising the dust environment of Saturn. The instrument is one of the three experiments which discovered the active ice geysers located at the south pole of Saturn's moon Enceladus in 2005. Later, a detailed compositional analysis of the water ice grains in Saturn's E ring system led to the discovery of large reservoirs of liquid water (oceans) below the icy crust of Enceladus. Finally, the determination of the dust-magnetosphere interaction and the discovery of the extended E ring (at least twice as large as predicted) allowed the definition of a dynamical dust model of Saturn's E ring describing the observed properties. This paper summarizes the discoveries of a 10-year story of success based on reliable measurements with the most advanced dust detector flown in space until today. This paper focuses on cruise results and findings achieved at Saturn with a focus on flux and density measurements. CDA discoveries related to the detailed dust stream

  10. Dielectric Property Measurements to Support Interpretation of Cassini Radar Data

    Science.gov (United States)

    Jamieson, Corey; Barmatz, M.

    2012-10-01

    Radar observations are useful for constraining surface and near-surface compositions and illuminating geologic processes on Solar System bodies. The interpretation of Cassini radiometric and radar data at 13.78 GHz (2.2 cm) of Titan and other Saturnian icy satellites is aided by laboratory measurements of the dielectric properties of relevant materials. However, existing dielectric measurements of candidate surface materials at microwave frequencies and low temperatures is sparse. We have set up a microwave cavity and cryogenic system to measure the complex dielectric properties of liquid hydrocarbons relevant to Titan, specifically methane, ethane and their mixtures to support the interpretation of spacecraft instrument and telescope radar observations. To perform these measurements, we excite and detect the TM020 mode in a custom-built cavity with small metal loop antennas powered by a Vector Network Analyzer. The hydrocarbon samples are condensed into a cylindrical quartz tube that is axially oriented in the cavity. Frequency sweeps through a resonance are performed with an empty cavity, an empty quartz tube inserted into the cavity, and with a sample-filled quartz tube in the cavity. These sweeps are fit by a Lorentzian line shape, from which we obtain the resonant frequency, f, and quality factor, Q, for each experimental arrangement. We then derive dielectric constants and loss tangents for our samples near 13.78 GHz using a new technique ideally suited for measuring liquid samples. We will present temperature-dependent, dielectric property measurements for liquid methane and ethane. The full interpretation of the radar and radiometry observations of Saturn’s icy satellites depends critically on understanding the dielectric properties of potential surface materials. By investigating relevant liquids and solids we will improve constrains on lake depths, volumes and compositions, which are important to understand Titan’s carbon/organic cycle and inevitably

  11. Retrievals of Jovian Tropospheric Phosphine from Cassini/CIRS

    Science.gov (United States)

    Irwin, P. G. J.; Parrish, P.; Fouchet, T.; Calcutt, S. B.; Taylor, F. W.; Simon-Miller, A. A.; Nixon, C. A.

    2004-01-01

    On December 30th 2000, the Cassini-Huygens spacecraft reached the perijove milestone on its continuing journey to the Saturnian system. During an extended six-month encounter, the Composite Infrared Spectrometer (CIRS) returned spectra of the Jovian atmosphere, rings and satellites from 10-1400 cm(exp -1) (1000-7 microns) at a programmable spectral resolution of 0.5 to 15 cm(exp -1). The improved spectral resolution of CIRS over previous IR instrument-missions to Jupiter, the extended spectral range, and higher signal-to-noise performance provide significant advantages over previous data sets. CIRS global observations of the mid-infrared spectrum of Jupiter at medium resolution (2.5 cm(exp -1)) have been analysed both with a radiance differencing scheme and an optimal estimation retrieval model to retrieve the spatial variation of phosphine and ammonia fractional scale height in the troposphere between 60 deg S and 60 deg N at a spatial resolution of 6 deg. The ammonia fractional scale height appears to be high over the Equatorial Zone (EZ) but low over the North Equatorial Belt (NEB) and South Equatorial Belt (SEB) indicating rapid uplift or strong vertical mixing in the EZ. The abundance of phosphine shows a similar strong latitudinal variation which generally matches that of the ammonia fractional scale height. However while the ammonia fractional scale height distribution is to a first order symmetric in latitude, the phosphine distribution shows a North/South asymmetry at mid latitudes with higher amounts detected at 40 deg N than 40 deg S. In addition the data show that while the ammonia fractional scale height at this spatial resolution appears to be low over the Great Red Spot (GRS), indicating reduced vertical mixing above the approx. 500 mb level, the abundance of phosphine at deeper levels may be enhanced at the northern edge of the GRS indicating upwelling.

  12. Cuzco and Rome, Peruvians and Andalucians in Inca Garcilaso’s work

    Directory of Open Access Journals (Sweden)

    Fermín Del Pino Díaz

    2011-12-01

    Full Text Available In this paper I offer a socio-cultural explanation of Inca Garcilaso’s Romanist program, taking into account the analysis of his biographical anchorages in both Perú and Spain, specially his andalusian experience. To do so, I follow the social events he lived through (the recent conquest of the Islamic world and presence of Jewish converts, as well as the more cultural aspects of his stay in Spain (Royal and nobility classicism, relationship with the Jesuits. By broadening the scope of the interpretation of his texts, we are no longer talking merely about an individual and isolated (if aristocratic experience, nor about a merely religious or literary option (even if it is expressed in such a way.

  13. Cuzco y Roma, peruanos y andaluces en la obra del Inca Garcilaso

    Directory of Open Access Journals (Sweden)

    Fermín del Pino-Díaz

    2011-12-01

    Full Text Available Se intenta ofrecer una explicación sociocultural del programa romanista del Inca Garcilaso en función de sus coordenadas biográficas (peruana y española, analizando especialmente su destino andaluz, tanto por sus coordenadas sociales (conquista reciente del mundo islámico y presencia de conversos judíos como por las propiamente culturales (clasicismo real y nobiliario, conexión con jesuitas. No se trata, pues, de una solución individual y aislada (por aristocrática, ni tampoco de una opción meramente literaria o religiosa (a pesar de expresarse en esa clave.

  14. INCA: a computational platform for isotopically non-stationary metabolic flux analysis.

    Science.gov (United States)

    Young, Jamey D

    2014-05-01

    13C flux analysis studies have become an essential component of metabolic engineering research. The scope of these studies has gradually expanded to include both isotopically steady-state and transient labeling experiments, the latter of which are uniquely applicable to photosynthetic organisms and slow-to-label mammalian cell cultures. Isotopomer network compartmental analysis (INCA) is the first publicly available software package that can perform both steady-state metabolic flux analysis and isotopically non-stationary metabolic flux analysis. The software provides a framework for comprehensive analysis of metabolic networks using mass balances and elementary metabolite unit balances. The generation of balance equations and their computational solution is completely automated and can be performed on networks of arbitrary complexity.

  15. Inca RTX HD高清广播图形解决方案

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Inscriber新推出的Inca RTX是一个灵活和功能强大的实时2D/3D图像、视频和图像剪辑工作平台.使用一个操作台就可以同时转播标清和高清信号。它可用于生成定制的广播应用软件.比如最新的体育比赛、天气情况的数据处理:互动和购物频道节目动态图像等处理和效果加强:新闻和信息频道中多层图像、视频和动画的处理。通过控制自己定制的接口界面。

  16. Literatura Inca (¿indígena? como representación de la literatura peruana

    Directory of Open Access Journals (Sweden)

    Gonzalo Espino Relucé

    2011-05-01

    Full Text Available Esta comunicación propone la relación entre las bellas letras y las manifestacionesdiscursivas vinculadas al indio; por eso, esboza las principales ideasliterarias que Jorge Basadre propone en Equivocaciones y cuyo trazo se puedeleer en Historia de la República del Perú.1 Se detiene en la importancia de laLiteratura inca, compilación de Basadre, cuya publicación constituye un recuentode la literatura prehispánica, la producción colonial y republicana de laescritura literaria quechua como representación de lo indígena para las culturasperuanas. Lo vinculo, asimismo, a la comprensión de la literatura como ejercicioheterogéneo y a las formas como el indio es representado en la escritura a finalesde la primera mitad del siglo XX.

  17. INCA TT-7. PRIMER CULTIVAR CUBANO DE TRITICALE (X. Triticosecale Wittmack

    Directory of Open Access Journals (Sweden)

    Rodolfo Plana Llerena

    2013-01-01

    Full Text Available En Cuba, no había sido probado con anterioridad el triticale. En este trabajo se informan las características de un cultivar de triticale seleccionado en Cuba (INCA TT- 7, seleccionado a partir de una colección de líneas procedentes del Centro Internacional de Mejoramiento de Maíz y Trigo (CIMMYT. Es tolerante a Helminthosporium sativum, resistente a la Septoria ( S. tritici y a la roya de la hoja ( P. triticina . Se destacó por altos rendimientos, producción de granos y masa seca para forraje. Su comportamiento ha sido validado en diferentes localidades del país del occidente y centro de Cuba y está propuesto para estudios de extensión en condiciones de producción.

  18. Precision Navigation of Cassini Images Using Rings, Icy Satellites, and Fuzzy Bodies

    Science.gov (United States)

    French, Robert S.; Showalter, Mark R.; Gordon, Mitchell K.

    2016-10-01

    Before images from the Cassini spacecraft can be analyzed, errors in the published pointing information (up to ~110 pixels for the Imaging Science Subsystem Narrow Angle Camera) must be corrected so that the line of sight vector for each pixel is known. This complicated and labor-intensive process involves matching the image contents with known features such as stars, rings, or moons. Metadata, such as lighting geometry or ring radius and longitude, must be computed for each pixel as well. Both steps require mastering the SPICE toolkit, a highly capable piece of software with a steep learning curve. Only after these steps are completed can the actual scientific investigation begin.We have embarked on a three-year project to perform these steps for all 400,000+ Cassini ISS images as well as images taken by the VIMS, UVIS, and CIRS instruments. The result will be a series of SPICE kernels that include accurate pointing information and a series of backplanes that include precomputed metadata for each pixel. All data will be made public through the PDS Ring-Moon Systems Node (http://www.pds-rings.seti.org). We expect this project to dramatically decrease the time required for scientists to analyze Cassini data.In a previous poster (French et al. 2014, DPS #46, 422.01) we discussed our progress navigating images using stars, simple ring models, and well-defined icy bodies. In this poster we will report on our current progress including the use of more sophisticated ring models, navigation of "fuzzy" bodies such as Titan and Saturn, and use of crater matching on high-resolution images of the icy satellites.

  19. Dimming titan revealed by the Cassini observations.

    Science.gov (United States)

    Li, Liming

    2015-02-04

    Here we report the temporal variation of Titan's emitted energy with the Cassini/CIRS observations. In the northern hemisphere, the hemispheric-average emitted power decreased from 2007 to 2009 and increased from 2009 to 2012-13, which make the net change insignificant (0.1 ± 0.2%) during the period 2007-2013. The decrease from 2007 to 2009 is mainly due to the cooling around the stratospause, and the increase from 2009 to 2012-13 is probably related to temporal variation of atmospheric temperature around the tropopuase in the northern hemisphere. In the southern hemisphere, the emitted power continuously decreased by 5.0 ± 0.6% from 2.40 ± 0.01 W/m(2) in 2007 to 2.28 ± 0.01 in 2012-13, which is mainly related to Titan's seasonal variation. The asymmetry in the temporal variation between the two hemispheres results in the global-average emitted power decreasing by 2.5 ± 0.6% from 2.41 ± 0.01 W/m(2) in 2007 to 2.35 ± 0.01 W/m(2) in 2012-13. The solar constant at Titan decreased by ~13.0% in the same period 2007-2013, which is much stronger than the temporal variation of emitted power. The measurements of Titan's absorbed solar power are needed to determine the temporal variation of the global energy budget.

  20. Saturn's Exploration Beyond Cassini-Huygens

    CERN Document Server

    Guillot, Tristan; Charnoz, Sébastien; Dougherty, Michele K; Read, Peter

    2009-01-01

    For its beautiful rings, active atmosphere and mysterious magnetic field, Saturn is a fascinating planet. It also holds some of the keys to understanding the formation of our Solar System and the evolution of giant planets in general. While the exploration by the Cassini-Huygens mission has led to great advances in our understanding of the planet and its moons, it has left us with puzzling questions: What is the bulk composition of the planet? Does it have a helium core? Is it enriched in noble gases like Jupiter? What powers and controls its gigantic storms? We have learned that we can measure an outer magnetic field that is filtered from its non-axisymmetric components, but what is Saturn's inner magnetic field? What are the rings made of and when were they formed? These questions are crucial in several ways: a detailed comparison of the compositions of Jupiter and Saturn is necessary to understand processes at work during the formation of these two planets and of the Solar System. This calls for the contin...

  1. The Cassini project: Lessons learned through operations

    Science.gov (United States)

    McCormick, Egan D.

    1998-01-01

    The Cassini space probe requires 180 238Pu Light-weight Radioisotopic Heater Units (LWRHU) and 216 238Pu General Purpose Heat Source (GPHS) pellets. Additional LWRHU and GPHS pellets required for non-destructive (NDA) and destructive assay purposes were fabricated bringing the original pellet requirement to 224 LWRHU and 252 GPHS. Due to rejection of pellets resulting from chemical impurities in the fuel and/or failure to meet dimensional specifications a total of 320 GPHS pellets were fabricated for the mission. Initial plans called for LANL to process a total of 30 kg of oxide powder for pressing into monolithic ceramic pellets. The original 30 kg commitment was processed within the time frame allotted; an additional 8 kg were required to replace fuel lost due to failure to meet Quality Assurance specifications for impurities and dimensions. During the time frame allotted for pellet production, operations were impacted by equipment failure, unacceptable fuel impurities levels, and periods of extended down time, >30 working days during which little or no processing occurred. Throughout the production process, the reality of operations requirements varied from the theory upon which production schedules were based.

  2. The prediction and management of aquatic nitrogen pollution across Europe: an introduction to the Integrated Nitrogen in European Catchments project (INCA

    Directory of Open Access Journals (Sweden)

    A. J. Wade

    2002-01-01

    Full Text Available Excess nitrogen in soils, fresh water, estuarine and marine systems contributes to nutrient enrichment in key ecosystems throughout Europe, often leading to detrimental environmental impacts, such as soil acidification or the eutrophication of water bodies. The Integrated Nitrogenmodel for European Catchments (INCA project aims to develop a generic version of the Integrated Nitrogen in Catchments (INCA model to simulate the retention and transport of nitrogen within river systems, thereby providing a tool to aid the understanding of nitrogen dynamics and for river-basin management/policy-making. To facilitate the development of the model, 10 partners have tested the INCA model with data collected in study sites located in eight European countries as part of the INCA project. This paper summarises the key nitrogen issues within Europe, describes the main aims and methodology of the INCA project, and sets the project in the context of the current major research initiatives at a European level. Keywords: Europe, European Union, nitrogen, nitrate, ammonium, river basin management, modelling, water chemistry, acidification, eutrophication, Water Framework Directive, INCA.

  3. La chicha y Atahualpa: el Encuentro de Cajamarca en la Suma y narración de los Incas de Juan Diez de Betanzos

    Directory of Open Access Journals (Sweden)

    Iván R. Reyna

    2010-12-01

    Full Text Available El Encuentro de Cajamarca es probablemente el momento más representativo de la conquista de los Incas y uno de los más simbólicos en el establecimiento del sistema colonial en la región andina. Mediante el análisis de la versión de Juan Diez de Betanzos que aparece en su Suma y Narración de los Incas, este ensayo trata de proponer una lectura alternativa sobre dicho evento, en la cual el Inca Atahualpa, luego de haber consumido chicha en exceso, se encontraría embriagado al momento de confrontarse con Fray Vicente de Valverde, lo que le impediría discernir con claridad la amenaza que significaban los invasores.The Cajamarca Encounter is probably the most representative event of the conquest of the Incas and one of the most symbolic in the establishment of the colonial system in the Andean region. By analyzing Juan Diez de Betanzos’ version which appears in his Narrative of the Incas, this essay proposes an alternative reading of the event, in which the Inca Atahualpa, after consuming chicha in excess, is probably drunk when confronted with Fray Vicente de Valverde, preventing him from clearly discerning the threat posed by the invaders.

  4. Man with a Mission: Jean-Dominique Cassini

    Science.gov (United States)

    Belkora, Leila

    2004-03-01

    Jean-Dominique Cassini, for whom the Cassini mission to Saturn is named, is best known for his early understanding of that planet's rings. This article is an overview of his influential career in astronomy and other scientific fields.= Born in Italy in1625 and formally educated at an early age, he was a professor of astronomy at the University of Bologna, a leading center of learning in Europe of the time. He was an early observer of Jupiter, Mars, and Venus. He is best known for constructing a giant pinhole camera in a cathedral that he used with a meridian line on the floor to track the Sun's image through the year, thus providing the Catholic Church with a reliable calendar. Cassini also used the pinhole camera observations to calculate the variation in the distance between the Sun and Earth, thus lending support to the Copernican (Sun-centered) view of the solar system. Cassini moved to Paris at the request of King Louis XIV, originally to oversee the surveying needed for a new map system of France, but ultimately he took over as the director of the Paris Observatory. Cassini's descendants ran the observatory there for the following century.

  5. The Convected Kappa Distribution Function at Jupiter: Details from the Voyager and Galileo Missions and a Comparison to Cassini Saturn Measurements

    Science.gov (United States)

    Kane, M.; Mitchell, D. G.; Mauk, B.; Carbary, J. F.; Hill, M. E.; Dialynas, K.; Krimigis, S. M.

    2016-12-01

    The Voyager and Galileo Missions allowed detailed measurements of 20 keV-2 MeV hot ion distributions in Jupiter's magnetosphere and beyond using the LECP detector on Voyager and EPD on Galileo. The normalized convected kappa distribution function, with isotropy assumed in the plasma convection frame, has well fit hot ion observed fluxes and thus has produced meaningful and ordered physical plasma parameters including the vector bulk velocity, the characteristic energy (temperature) of the distribution, and the high energy spectral index. The kappa model produces temperatures that indicate expansion and adiabatic cooling of hot ions in the nightside, but not in the dayside. Further, there are significant variations in the plasma parameters with time and local time. There is also a boundary layer present near but within the dawn magnetopause where distribution functions were generated from data analysis of the very distant Voyager 2 crossing of this region. Here the flow is apparently entrained into the magnetosheath flow, but temperatures are hot and consistent with rapid transport of plasma from regions of the magnetosphere closer to Jupiter. These observations have led to the proposal of an empirical model of the general convection pattern at Jupiter. Remarkably, application of the convected kappa distribution model to Saturn using Cassini INCA and CHEMS measurements produces a convection pattern and kappa distribution temperature profiles that are remarkably similar when scaled by the sub-solar magnetopause distance and radial size of the planets.

  6. Cassini-VIMS observations of particles in Enceladus' plume and the E ring

    Science.gov (United States)

    Hedman, M. M.; Nicholson, P. D.; Showalter, M. R.

    2008-09-01

    One of the most surprising discoveries from the Cassini mission is that Saturn's moon Enceladus vents material from its interior, launching gas and particulate matter high above its surface to supply water molecules to the inner magnetosphere and ice-rich grains to the E ring. While data from various instruments onboard Cassini have already provided important information about such parameters as the heat flux from the surface and the distributions of dust and gas within the plume, there is still considerable debate regarding several aspects of this phenomenon. In particular, there are several different models for how solid material is produced and accelerated within the moon, some involve boiling liquids [1] and others disassociating clathrates [2]. We report here on an investigation of the near infrared spectra of the plume between 0.85 and 5.1microns obtained by the Visual and Infrared Mapping Spectrometer (VIMS) instrument [3]. These data provide information on the velocity distribution of particles launched from the surface, which should constrain possible models for the acceleration of solids within the moon [4]. The relevant plume spectral data were obtained at high phase angles (roughly 160°), where diffraction by small particles is the dominant process responsible for scattering light from the sun into the instrument. In fact, provided the particle size distribution is sufficiently steep and the particles' optical constants do not vary too much with wavelength (which should be true outside of the strong water-ice absorption band at three microns), particles of a given size s will most efficiently scatter light with a wavelength ? proportional to s (the constant of proportionality being determined primarily by the phase angle of the observation). Thus there is a relatively direct mapping between the shape of the spectrum and the shape of the particle size distribution, which allows us to compute approximate model spectra for a fairly comprehensive suite of

  7. Cusp observation at Saturn's high-latitude magnetosphere by the Cassini spacecraft.

    Science.gov (United States)

    Jasinski, J M; Arridge, C S; Lamy, L; Leisner, J S; Thomsen, M F; Mitchell, D G; Coates, A J; Radioti, A; Jones, G H; Roussos, E; Krupp, N; Grodent, D; Dougherty, M K; Waite, J H

    2014-03-16

    We report on the first analysis of magnetospheric cusp observations at Saturn by multiple in situ instruments onboard the Cassini spacecraft. Using this we infer the process of reconnection was occurring at Saturn's magnetopause. This agrees with remote observations that showed the associated auroral signatures of reconnection. Cassini crossed the northern cusp around noon local time along a poleward trajectory. The spacecraft observed ion energy-latitude dispersions-a characteristic signature of the terrestrial cusp. This ion dispersion is "stepped," which shows that the reconnection is pulsed. The ion energy-pitch angle dispersions suggest that the field-aligned distance from the cusp to the reconnection site varies between ∼27 and 51 RS . An intensification of lower frequencies of the Saturn kilometric radiation emissions suggests the prior arrival of a solar wind shock front, compressing the magnetosphere and providing more favorable conditions for magnetopause reconnection. We observe evidence for reconnection in the cusp plasma at SaturnWe present evidence that the reconnection process can be pulsed at SaturnSaturn's cusp shows similar characteristics to the terrestrial cusp.

  8. Titan's interior from Cassini-Huygens

    Science.gov (United States)

    Tobie, G.; Baland, R.-M.; Lefevre, A.; Monteux, J.; Cadek, O.; Choblet, G.; Mitri, G.

    2013-09-01

    The Cassini-Huygens mission has brought many informations about Titan that can be used to infer its interior structure: the gravity field coefficients (up to degree 3, [1]), the surface shape (up to degree 6, [2]), the tidal Love number [1], the electric field [3], and the orientation of its rotation axis [4]. The measured obliquity and gravity perturbation due to tides, as well as the electric field, are lines of evidence for the presence of an internal global ocean beneath the ice surface of Titan [5,1,3]. The observed surface shape and gravity can be used to further constrain the structure of the ice shell above the internal ocean. The presence of a significant topography associated with weak gravity anomalies indicates that deflections of internal interface or lateral density variations may exist to compensate the topography. To assess the sources of compensation, we consider interior models including interface deflections and/or density variations, which reproduces simultaneously the surface gravity and long-wavelength topography data [6]. Furthermore, in order to test the long-term mechanical stability of the internal mass anomalies, we compute the relaxation rate of each internal interface in response to surface mass load. We show that the topography can be explained either by defections of the ocean/ice interface or by density variations in an upper crust [6]. For non-perfectly compensated models of the outer ice shell, the present-day structure is stable only for a conductive layer above a relatively cold ocean (for bottom viscosity > 1016 Pa.s, T Love number and the obliquity. To derive the possible density profile, the obliquity is computed from a Cassini state model for a satellite with an internal liquid layer, each layer having an ellipsoidal shape consistent with the measured surface shape and gravity field [7]. We show that, once the observed surface flattening is taken into account, the measured obliquity can be reproduced only for internal models

  9. Cassini's Cameras Catch Delightful Dynamics Surrounding Saturn

    Science.gov (United States)

    Burns, J. A.; Cassini Imaging Team

    2005-05-01

    Saturn's rings and satellites delight DDA members because of the baroque variety of their extant features and the pivotal role played by resonances. I will review some of the highlights imaged by Cassini during the first nine months of its mission. Numerous density waves, mainly in the outer A ring, were identified with unprecedented accuracy from high-resolution approach images. These include waves initiated by the classically known perturbing satellites, but also by tiny (though nearby) Atlas and Pan, the latter embedded within the A ring. Wavelet analyses have eased identification of waves, allowing estimates of the ring's areal mass density and viscosity, and the perturber's mass. The latter, when combined with satellite images, indicate that low satellite densities (ρ ˜ 0.5 g-cm-3) are the norm. Pan pries open the Encke gap, producing edge waves and imposing numerous (kinematic) gravity wakes. A narrow ringlet within that gap, coincident with Pan's orbit, shows clumps and wiggles that march along relative to Pan, presumably horseshoeing particles. All aspects of the narrow Keeler gap still await explanation. Several previously unknown structures may result from collective effects or non-linear instabilities as particles are driven together. The F ring's structure is beautifully complex but can be mostly understood as resulting from Prometheus's tugs. A few isolated narrow ringlets have been found, occasionally sharing the paths of known satellites. Some parts of the rings show time variability already. We eagerly await the switch of co-orbital Janus/Epimetheus in 2006, and again in 2010, and the plunge of Prometheus into the F ring in 2010. To date, three new satellites have been discovered: two orbit between the classical moons Mimas and Enceladus, while the third is a trailing Lagrangian of Dione. Several other objects, probably temporary clumps of material, were sighted near the F ring.

  10. Cassini detection of Enceladus' cold water-group plume ionosphere

    Science.gov (United States)

    Tokar, R. L.; Johnson, R. E.; Thomsen, M. F.; Wilson, R. J.; Young, D. T.; Crary, F. J.; Coates, A. J.; Jones, G. H.; Paty, C. S.

    2009-07-01

    This study reports direct detection by the Cassini plasma spectrometer of freshly-produced water-group ions (O+, OH+, H2O+, H3O+) and heavier water dimer ions (HxO2)+ very close to Enceladus where the plasma begins to emerge from the plume. The data were obtained during two close (52 and 25 km) flybys of Enceladus in 2008 and are similar to ion data in cometary comas. The ions are observed in detectors looking in the Cassini ram direction exhibiting energies consistent with the Cassini speed, indicative of a nearly stagnant plasma flow in the plume. North of Enceladus the plasma slowing commences about 4 to 6 Enceladus radii away, while south of Enceladus signatures of the plasma interaction with the plume are detected 22 Enceladus radii away.

  11. Overview of the Cassini in-situ magnetosphere measurements and solar wind modelling during the 2013 Saturn Aurora Campaign

    Science.gov (United States)

    Bunce, E. J.; Badman, S. V.; Cowley, S. W. H.; Jinks, S. L.; Provan, G.; Burton, M.; Crary, F. J.; Dougherty, M. K.; Kurth, W. S.; Luhmann, J.; Mitchell, D. G.; Zheng, Y.

    2013-09-01

    The Saturn Aurora Campaign 2013 is a coordinated effort to provide a clearer understanding of Saturn's auroral emissions at multiple wavelengths in the upper atmosphere, and their associated magnetospheric signatures and dynamics. In addition, modelling and Earth-based observations of the solar wind conditions throughout the campaign provide an important insight to the way in which Saturn's magnetosphere responds to the changing conditions in interplanetary space. Structures such as Corotating Interaction Regions (CIRs) are thought to play a significant role in the modulation of Saturn's auroral emissions via abrupt changes in the dynamic pressure associated with forward shocks at the start of the CIR compression regions. Recent observations from the Cassini spacecraft at Saturn have also taught us that the "magnetosphere oscillations" observed in magnetic field perturbations in the northern and southern hemispheres, which are associated with the SKR modulations in each hemisphere, significantly affect the magnetosphere and auroral emissions. During April and May 2013 a combination of the Hubble Space Telescope (HST) ultraviolet (UV) instrument the Advanced Camera for Surveys (ACS), and ground-based infrared (IR) telescopes observed the northern hemisphere auroras, whilst the Cassini spacecraft's remote sensing instruments (the Ultraviolet Imaging Spectrograph-UVIS, the Visual and Infrared Mapping Spectrometer-VIMS, and the Imaging Science SubSystem-ISS) made simultaneous (or near-simultaneous) observations of the UV, IR and visible auroras respectively, in one or other hemisphere. At the same time, the "in situ" instruments on board Cassini measured the magnetic field, plasma populations, and radio plasma wave emissions in Saturn's magnetosphere. Here we present an overview of the in situ magnetosphere measurements during the campaign, along with an overview of the predicted solar wind conditions upstream of Saturn from modeling work. We will discuss the evidence

  12. Inhibition of Fusion of Chlamydia trachomatis Inclusions at 32°C Correlates with Restricted Export of IncA

    OpenAIRE

    Fields, K. A.; Fischer, E.; Hackstadt, T

    2002-01-01

    Chlamydia trachomatis is an obligate intracellular bacterium that develops within a parasitophorous vacuole termed an inclusion. The inclusion is nonfusogenic with lysosomes but intercepts lipids from a host cell exocytic pathway. Initiation of chlamydial development is concurrent with modification of the inclusion membrane by a set of C. trachomatis-encoded proteins collectively designated Incs. One of these Incs, IncA, is functionally associated with the homotypic fusion of inclusions. Incl...

  13. Cholos, incas y fusionistas: El nuevo Perú y la globalización de lo andino

    OpenAIRE

    Annelou Ypeij

    2013-01-01

    Abstract:   Cholos, incas and fusionistas: The New Peru and the Globalization of 'Lo Andino'This Exploration deals with the cultural changes in Peru from the year 2000. Peru has become a society with more economic, political, social and global opportunities. Within this context, significant cultural changes can be noted. This essay explores cultural expressions such as the weaving associations of the women of Chinchero, the Peruvian cuisine and the rock band Uchpa. All have in common that the...

  14. Del discurso escrito colonial al discurso prehispánico: hacia el sistema sociocosmológico inca de oposición y complementariedad

    Directory of Open Access Journals (Sweden)

    1997-01-01

    Full Text Available DU DISCOURS ECRIT COLONIAL AU DISCOURS PREHISPANIQUE : VERS LE SYSTEME SOCIOCOSMOLOGIQUE INCA D’OPPOSITION ET DE COMPLEMENTARITE. On retrouve dans les récits des chroniques coloniales sur la guerre des Incas contre les Chancas -et dans ceux de la guerre des Incas contre les Alcauizas- la tradition indigène des batailles rituelles (ou tinkuy qui commémoraient pour le solstice de décembre la nécessaire victoire de l’infant Yupanqui (incarnation du Jeune Soleil triomphant sur des ennemis conventionnels représentant le risque d’intempéries et de mauvaises récoltes. À cette occasion, le nouvel Inca qui succédait à son père (incarnation du Vieux Soleil, devait favoriser le changement harmonieux dans le cycle cosmique et végétal, en même temps qu’il devait reconstituer, au moins symboliquement, l’ordre social et politique. Encontramos en los relatos de las crónicas coloniales sobre la guerra de los incas contra los chancas -y en los de la guerra de los incas contra los alcauizas- la tradición indígena de unas batallas rituales (o tinkuy que conmemoraban, por el solsticio de diciembre, la necesaria victoria del infante Yupanqui (encarnación del Sol Joven triunfante sobre enemigos convencionales que representaban el riesgo de intemperie y de mala cosecha. Con este motivo, el nuevo Inca que sucedía a su padre (encarnación del Sol Viejo debía propiciar alternancias armoniosas en el ciclo cósmico y vegetal. Juntamente, debía reconstituir, por lo menos simbólicamente, el orden social y político. FROM COLONIAL WRITTEN DISCOURSE TO PREHISPANIC DISCOURSE: TOWARDS THE INCA SOCIOCOSMOLOGICAL SYSTEM OF OPPOSITION AND COMPLEMENTARITY. The indigenous tradition of ritual battles (or tinkuy, which, in connection with the December solstice, commemorated the necessary victory of the prince Yupanqui (incarnation of the triumphant Young Sun over his conventional enemies (symbolizing the risk of bad weather and poor crops is to be found in

  15. Updating the Reference Trajectory for the Cassini Solstice Mission

    Science.gov (United States)

    Valerino, Powtawche N.

    2014-01-01

    The Cassini-Huygens deep-space probe has successfully completed a four-year prime tour and a two-year extended tour of the Saturnian system. Now in a second extended phase called the Solstice Mission, the Cassini spacecraft will continue to gather data as directed by the reference trajectory until 2017. This paper will describe the process of how a reference trajectory update is prepared and delivered to the project by the navigation team during Solstice Mission flight operations. This paper will also document the timeline of products released and utilized, as well as the study to include an Enceladus occultation observation that occurs in 2016.

  16. Cassini-Huygens Ion Neutral Mass Spectrometer and the Future

    Science.gov (United States)

    Waite, J. Hunter

    2014-05-01

    The Cassini-Huygens Ion Neutral Mass Spectrometer (Cassini INMS) designed and built by Hasso Niemann has revolutionized our understanding of the Saturn system and demonstrated the importance of mass spectrometry as a tool for understanding formation, evolution, and chemical processes. In this talk that honors the accomplishments of Hasso I will discuss: 1) the major discoveries of INMS at Titan, Enceladus, and the other icy moons of Saturn, 2) the new perspective this has given us on understanding the formation and evolution of the outer solar system, and 3) the implications for future studies in the outer solar system using mass spectrometry.

  17. Going Out in a Blaze of Glory: Cassini's Grand Finale

    Science.gov (United States)

    Spilker, Linda; Edgington, Scott G.; Altobelli, Nicolas

    2016-10-01

    The Cassini-Huygens mission, a joint collaboration between NASA, ESA and the Italian Space Agency, is approaching its final year of operations after more than 12 years in Saturn orbit. Cassini will send back its final bits of unique data on 15 September 2017 as it plunges into Saturn's atmosphere, vaporizing and satisfying planetary protection requirements.Since early 2016 Cassini's orbital inclination has been slowly increasing. In November Cassini will transition to a series of 20 orbits with peripases just outside Saturn's F ring that include some of the closest flybys of the tiny ring moons and excellent views of the F ring and outer A ring. Cassini's final close flyby of Titan will propel it across Saturn's main rings and into its final orbits.Cassini's Grand Finale begins in April 2017 and is comprised of 22 orbits at an inclination of 63 degrees. Cassini will repeatedly dive between the innermost ring and Saturn's upper atmosphere providing insights into fundamental questions unattainable during the rest of the mission. It will be the first spacecraft to explore this region.These close orbits provide the highest resolution observations of both the rings and Saturn, and direct in situ sampling of the ring particles' composition, plasma, Saturn's exosphere and the innermost radiation belts. Saturn's gravitational field will be measured to unprecedented accuracy, providing information on Saturn's interior structure and mass distribution in the rings. Probing the magnetic field will give insight into the nature of the magnetic dynamo and the true rotation rate of Saturn's interior. The ion and neutral mass spectrometer will sniff the exosphere and upper atmosphere and examine water-based molecules originating from the rings. The cosmic dust analyzer will sample particle composition from different parts of the main rings.New science highlights and science objectives from Cassini's final orbits will be discussed.This work was carried out in part at the Jet

  18. Modelling the long term impact of climate change on the carbon budget of Lake Simcoe, Ontario using INCA-C.

    Science.gov (United States)

    Oni, S K; Futter, M N; Molot, L A; Dillon, P J

    2012-01-01

    This study presents a process-based model of dissolved organic carbon concentration ([DOC]) in catchments draining into Lake Simcoe, Ontario. INCA-C, the Integrated Catchment model for Carbon, incorporates carbon biogeochemical processes in a terrestrial system with hydrologic flow paths to simulate watershed wide [DOC]. The model successfully simulates present-day inter-annual and seasonal [DOC] dynamics in tributaries draining catchments with mixed or contrasting land cover in the Lake Simcoe watershed (LSW). The sensitivity of INCA-C to soil moisture, hydrologic controls and land uses within a watershed demonstrates its significance as a tool to explore pertinent environmental issues specific to the LSW. Projections of climate change under A1B and A2 SRES scenarios suggest a continuous monotonic increase in [DOC] in surface waters draining into Lake Simcoe. Large variations in seasonal DOC dynamics are predicted to occur during summer with a possibility of displacement of summer [DOC] maxima towards winter and a prolongation of summer [DOC] levels into the autumn. INCA-C also predicts possible increases in dissolved inorganic carbon in some tributaries with rising temperature suggesting increased CO(2) emissions from rivers as climate changes. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Counter Data of the Cosmic Dust Analyzer aboard the Cassini spacecraft and possible "dust clouds" at Saturn

    OpenAIRE

    Khalisi, Emil; Srama, Ralf; Grün, Eberhard

    2014-01-01

    We present the impact rates of dust particles recorded by the Cosmic Dust Analyzer (CDA) aboard the Cassini spacecraft. The "dust counters" evaluate the quality of an impact and give rise to the apparent density of dust particles in space. The raw data is pre-selected and refined to a new structure that serves to a better investigation of densities, flows, and properties of interplanetary dust grains. Our data is corrected for the dead time of the instrument and corresponds to an assumed Kepl...

  20. First Results From the Gas Chromatograph Mass Spectrometer (GCMS) Experiment on the Cassini-Huygens Probe

    Science.gov (United States)

    Niemann, Hasso B.; Demick, J.; Haberman, J.; Harpold, D.; Kasprzak, W.; Raaen, E.; Way, S.; Atreya, S.; Carignan, G.; Bauer, S.

    2005-01-01

    The Huygens Probe of the Cassini Huygens Mission entered the atmosphere of the moon Titan on January 14,2005. The GCMS was part of the instrument complement on the Probe to measure in situ the chemical composition of the atmosphere during the probe descent and to support the Aerosol Collector Pyrolyser (ACP) experiment by serving as detector for the pyrolization products. The GCMS employed a quadrupole mass filter with a secondary electron multiplier detection system and a gas sampling system providing continuous direct atmospheric composition measurements and batch sampling through three gas chromatographic (GC) columns. The mass spectrometer employed five electron impact ion sources with available electron energies of either 70 or 25 eV. Three ion sources served as detectors for the GC columns and two were dedicated to direct atmosphere sampling and ACP gas sampling, respectively. The GCMS gas inlet was heated to prevent condensation, and served to evaporate surface constituents after impact.

  1. Cassini finds molecular hydrogen in the Enceladus plume: Evidence for hydrothermal processes

    Science.gov (United States)

    Waite, J. Hunter; Glein, Christopher R.; Perryman, Rebecca S.; Teolis, Ben D.; Magee, Brian A.; Miller, Greg; Grimes, Jacob; Perry, Mark E.; Miller, Kelly E.; Bouquet, Alexis; Lunine, Jonathan I.; Brockwell, Tim; Bolton, Scott J.

    2017-04-01

    Saturn’s moon Enceladus has an ice-covered ocean; a plume of material erupts from cracks in the ice. The plume contains chemical signatures of water-rock interaction between the ocean and a rocky core. We used the Ion Neutral Mass Spectrometer onboard the Cassini spacecraft to detect molecular hydrogen in the plume. By using the instrument’s open-source mode, background processes of hydrogen production in the instrument were minimized and quantified, enabling the identification of a statistically significant signal of hydrogen native to Enceladus. We find that the most plausible source of this hydrogen is ongoing hydrothermal reactions of rock containing reduced minerals and organic materials. The relatively high hydrogen abundance in the plume signals thermodynamic disequilibrium that favors the formation of methane from CO2 in Enceladus’ ocean.

  2. Laser Mode Behavior of the Cassini CIRS Fourier Transform Spectrometer at Saturn

    Science.gov (United States)

    Brasunas, John C.

    2012-01-01

    The CIRS Fourier transform spectrometer aboard the NASA/ESA/ASI Cassini orbiter has been acquiring spectra of the Saturnian system since 2004. The CIRS reference interferometer employs a laser diode to trigger the interferogram sampling. Although the control of laser diode drive current and operating temperature are stringent enough to restrict laser wavelength variation to a small fraction of CIRS finest resolution element, the CIRS instrument does need to be restarted every year or two, at which time it may start in a new laser mode. By monitoring the Mylar absorption features in uncalibrated spectra due to the beam splitter Mylar substrate, it can be shown that these jumps are to adjacent modes and that most of the eight-year operation so far is restricted to three adjacent modes. For a given mode, the wavelength stability appears consistent with the stability of the laser diode drive curren.t and operating temperature.

  3. Los palacios en la Costa Central durante los periodos Tardíos: de Pachacamac al Inca

    Directory of Open Access Journals (Sweden)

    2004-01-01

    Full Text Available LES PALAIS DE LA COTE CENTRALE DURANT LES PERIODES RECENTES : DE PACHACAMAC A L’INCA. Des études récentes portant sur la côte centrale du Pérou ont mis en évidence le fait que durant la période Intermédiaire récent (XIe au XVe s. dne l’architecture reliée au pouvoir était étroitement liée à un type particulier d’édifice : la résidence d’élite ou palais. Les données indiquent également que durant l’occupation inca dans la même région (15-16e siècles, ce type de bâtiment conserve toute son importance en tant que symbole spécifique du pouvoir politique des élites gouvernantes (c'est-à-dire les curacas. La persistance des palais de tradition locale comme référents de l’organisation politique de ce que l’on appelle la province inca de Pachacamac - tout du moins dans la zone correspondant au fleuve Rimac - met en evidence un thème toujours d’actualité dans le débat archéologique : quelles furent les caractéristiques du contrôle politique résultant de l’occupation inca dans cette partie du Tahuantinsuyu ? Quelle fut la reaction des élites locales face à l’ordre nouveau issu de la conquête ? Cet article développe ce thème à partir de la définition des attributs formels des palais, la description et l’usage des artefacts associés à ceux-ci, ainsi que l’analyse des sources historiques qui rendent compte des caractéristiques particulières de la société préhispanique récente de la côte centrale. Recientes estudios para la costa central del Perú han evidenciado que durante el periodo Intermedio Tardío (S. XI a XV d.C. la arquitectura del poder estuvo íntimamente ligada a un tipo particular de edificio: la residencia de elite o palacio. Las evidencias también indican que luego de la ocupación Inca de la misma región (S. XV, esta variedad de edificio conservó su vigencia como símbolo distintivo del poder político de las elites gobernantes (v.g. curacas. La persistencia de los palacios de

  4. Actitudes homofóbicas entre los indígenas del Nuevo Mundo: los casos azteca, inca y mapuche en fuentes de los siglos XVI y XVII/Homophobic Attitudes Among Indigenous People in the New World: Aztecs, Incas and Mapuches Through 16th and 17th Century Sources

    National Research Council Canada - National Science Library

    Mauricio González Arenas; César Gamboa

    2015-01-01

    ... toward homosexual behavior. It argues, analyzing Aztec, Inca and Mapuche attitudes from sixteenth-century and seventeenth-century sources, that America was not at all the gay paradise that many have wanted to see and publicize...

  5. Modelling the non-gravitational acceleration during Cassini's gravitation experiments

    CERN Document Server

    Bertolami, O; Gil, P J S; Páramos, J

    2014-01-01

    In this work we present a computation of the thermally generated acceleration on the Cassini probe during its solar conjunction experiment, obtained from a model of the spacecraft. We use a point-like source method to build a thermal model of the vehicle and find that the results are in close agreement with the estimates of this effect performed through Doppler data analysis.

  6. Automated Scheduling of Science Activities for Titan Encounters by Cassini

    Science.gov (United States)

    Ray, Trina L.; Knight, Russel L.; Mohr, Dave

    2014-01-01

    In an effort to demonstrate the efficacy of automated planning and scheduling techniques for large missions, we have adapted ASPEN (Activity Scheduling and Planning Environment) [1] and CLASP (Compressed Large-scale Activity Scheduling and Planning) [2] to the domain of scheduling high-level science goals into conflict-free operations plans for Titan encounters by the Cassini spacecraft.

  7. Cassini's Compositae genera: A nomenclatural and taxonomic assessment

    NARCIS (Netherlands)

    Flann, C.M.; Greuter, W.; Hind, D.J.N.

    2010-01-01

    Work on the Global Compositae Checklist has highlighted uncertainties and errors in the nomenclatural parameters of many genera and subgenera described by Henri Cassini. Problems concern rank (subgenus vs. genus); type designation; correct place of valid publication; alternative names; and other

  8. Observational Constraints on Planet Nine: Cassini Range Observations

    CERN Document Server

    Holman, Matthew J

    2016-01-01

    We significantly constrain the sky position, distance, and mass of a possible additional, distant planet in the solar system by examining its influence on the distance between Earth and the Cassini Spacecraft. Our preferred region is approximately centered on (RA, Dec) = ($40\\arcdeg$, $-15\\arcdeg$), extending approximately 20 degrees in all directions.

  9. In Situ Cassini Spacecraft Observations of Turbulence in Saturn's Magnetosheath

    Science.gov (United States)

    Hadid, L.; Sahraoui, F.; Retino, A.; Modolo, R.; Canu, P.; Jackman, C.; Masters, A.; Dougherty, M. K.; Gurnett, D. A.

    2013-09-01

    Throughout this work we investigate, the properties of turbulence in the Magnetosheath of Saturn. To do so, we computed Power Spectral Densities (PSD) based on Cassini interplanetary magnetic field data between 2004 and 2007. As a preliminary result, we show the absence of the Kolmogorov scale ~ f-5/3 in the inertial range whereas only the f-1 scale is present.

  10. Actinide fission and capture cross section measurements at ILL: the Mini-INCA project

    Energy Technology Data Exchange (ETDEWEB)

    Letourneau, A.; Bringer, O.; Chabod, S.; Fioni, G.; Foucher, Y.; Marie, F.; Veyssiere, Ch. [CEA/Saclay/DSM/DAPNIA - Gif-sur-Yvette (France); Mahamid, I. Al. [Lawrence Berkeley National Laboratory, E.H. and S division, Berkeley CA (United States); Blandin, Ch. [CEA/Cadarache/DEN/DER/SPEX - Saint-Paul-lez-Durances (France); Chartier, F. [CEA/Saclay/DEN/DPC/SECR - Gif-sur-Yvette (France); Faust, H.; Mutti, P. [Institut Laue-Langevin, BP 156, F-38042 Grenoble Cedex 9 (France)

    2005-07-01

    Fission cross section of short-lived minor actinides is of prime importance for the incineration of minor actinides in high and thermal neutron fluxes. But due to the shortness of their half-lives, measurements are difficult to handle on these isotopes and the existing data present some large discrepancies. An original method has been developed, in the framework of the Mini-INCA project at ILL, to measure the fission and capture cross sections of minor actinides with low error bars associated even for short-lived isotopes. This method lies on a quasi on-line alpha- and gamma-spectroscopy of irradiated samples and on the use of fission micro-chambers. Coupled to a very powerful Monte-Carlo simulation, both microscopic information on nuclear reactions (total and partial cross sections for neutron capture and/or fission reactions) and macroscopic information on transmutation and incineration potentials could be gathered. In this paper, the method is explained in its originality and some recent results are given and compared with existing measurements and evaluated data libraries. (authors)

  11. Cassini Science Highlights: Surprises in the Saturn System

    Science.gov (United States)

    Spilker, Linda J.

    2012-10-01

    Cassini’s exploration of the Saturn system has generated a treasure trove of scientific data on Saturn, Titan, Enceladus, and other diverse icy satellites, the rings, and magnetosphere. After eight years of close study of this exceptionally complex and dynamic environment, Cassini is still unveiling new scientific discoveries that continue to amaze us. Standout recent highlights include aftereffects from Saturn’s huge storm, a possible subsurface ocean on Titan, close flybys of icy satellites, migrating ring “propellers”, and unexpected variations in Saturn kilometric radiation periodicities. Current observations show seasonal changes including the formation of a polar vortex at Titan’s south pole. To date, Cassini has observed Saturn from just after northern winter solstice through northern spring equinox and now is observing the Saturn system in the previously unobserved period leading up to northern summer solstice. In the remaining five years of the on-going Solstice Mission, Cassini will continue to study seasonally and temporally dependent processes. Given the long Saturnian year ( 30 years) the longevity of Cassini is essential for elucidating seasonal change in the Saturn system. The grand finale of the mission occurs in 2017, when a series of inclined orbits brings Cassini between the innermost D ring and the upper regions of Saturn’s atmosphere. This geometry will offer unique opportunities for new discoveries and ground-breaking science, including Saturn interior structure science from otherwise unobtainable gravity and magnetic field measurements and unprecedented determination of the ring mass, currently uncertain by an order of magnitude. This Proximal orbit phase is similar to Juno’s mission at Jupiter. Comparing Jupiter and Saturn is the first step toward the next great leap in solar system origins research. This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA

  12. Host adaptation of Chlamydia pecorum towards low virulence evident in co-evolution of the ompA, incA, and ORF663 Loci.

    Science.gov (United States)

    Mohamad, Khalil Yousef; Kaltenboeck, Bernhard; Rahman, Kh Shamsur; Magnino, Simone; Sachse, Konrad; Rodolakis, Annie

    2014-01-01

    Chlamydia (C.) pecorum, an obligate intracellular bacterium, may cause severe diseases in ruminants, swine and koalas, although asymptomatic infections are the norm. Recently, we identified genetic polymorphisms in the ompA, incA and ORF663 genes that potentially differentiate between high-virulence C. pecorum isolates from diseased animals and low-virulence isolates from asymptomatic animals. Here, we expand these findings by including additional ruminant, swine, and koala strains. Coding tandem repeats (CTRs) at the incA locus encoded a variable number of repeats of APA or AGA amino acid motifs. Addition of any non-APA/AGA repeat motif, such as APEVPA, APAVPA, APE, or APAPE, associated with low virulence (PincA CTRs (P = 0.0028). In ORF663, high numbers of 15-mer CTRs correlated with low virulence (P = 0.0001). Correction for ompA phylogram position in ORF663 and incA abolished the correlation between genetic changes and virulence, demonstrating co-evolution of ompA, incA, and ORF663 towards low virulence. Pairwise divergence of ompA, incA, and ORF663 among isolates from healthy animals was significantly higher than among strains isolated from diseased animals (P≤10-5), confirming the longer evolutionary path traversed by low-virulence strains. All three markers combined identified 43 unique strains and 4 pairs of identical strains among all 57 isolates tested, demonstrating the suitability of these markers for epidemiological investigations.

  13. Cassini Scientist for a Day: a tactile experience

    Science.gov (United States)

    Canas, L.; Altobelli, N.

    2012-09-01

    In September 2011, the Cassini spacecraft took images of three targets and a challenge was launched to all students: to choose the one target they thought would provide the best science and to write an essay explaining their reasons (more information on the "Cassini Scientist for a Day" essay contest official webpage in: http://saturn.jpl.nasa.gov/education/scientistforaday10thedition/, run by NASA/JPL) The three targets presented were: Hyperion, Rhea and Titan, and Saturn. The idea behind "Cassini Scientist for a Day: a tactile experience" was to transform each of these images into schematic tactile images, highlighting relevant features apprehended through a tactile key, accompanied by a small text in Braille with some additional information. This initial approach would allow reach a broader community of students, more specifically those with visual impairment disabilities. Through proper implementation and careful study cases the adapted images associated with an explanatory key provide more resources in tactile astronomy. As the 2012 edition approaches a new set of targeted objet images will be once again transformed and adapted to visually impaired students and will aim to reach more students into participate in this international competition and to engage them in a quest to expand their knowledge in the amazing Cassini discoveries and the wonders of Saturn and its moons. As the winning essays will be published on the Cassini website and contest winners invited to participate in a dedicated teleconference with Cassini scientists from NASA's Jet Propulsion Laboratory, this initiative presents a great chance to all visually impaired students and teachers to participate in an exciting experience. These initiatives must be complemented with further information to strengthen the learning experience. However they stand as a good starting point to tackle further astronomical concepts in the classroom, especially this field that sometimes lacks the resources. Although

  14. Host adaptation of Chlamydia pecorum towards low virulence evident in co-evolution of the ompA, incA, and ORF663 Loci.

    Directory of Open Access Journals (Sweden)

    Khalil Yousef Mohamad

    Full Text Available Chlamydia (C. pecorum, an obligate intracellular bacterium, may cause severe diseases in ruminants, swine and koalas, although asymptomatic infections are the norm. Recently, we identified genetic polymorphisms in the ompA, incA and ORF663 genes that potentially differentiate between high-virulence C. pecorum isolates from diseased animals and low-virulence isolates from asymptomatic animals. Here, we expand these findings by including additional ruminant, swine, and koala strains. Coding tandem repeats (CTRs at the incA locus encoded a variable number of repeats of APA or AGA amino acid motifs. Addition of any non-APA/AGA repeat motif, such as APEVPA, APAVPA, APE, or APAPE, associated with low virulence (P<10-4, as did a high number of amino acids in all incA CTRs (P = 0.0028. In ORF663, high numbers of 15-mer CTRs correlated with low virulence (P = 0.0001. Correction for ompA phylogram position in ORF663 and incA abolished the correlation between genetic changes and virulence, demonstrating co-evolution of ompA, incA, and ORF663 towards low virulence. Pairwise divergence of ompA, incA, and ORF663 among isolates from healthy animals was significantly higher than among strains isolated from diseased animals (P≤10-5, confirming the longer evolutionary path traversed by low-virulence strains. All three markers combined identified 43 unique strains and 4 pairs of identical strains among all 57 isolates tested, demonstrating the suitability of these markers for epidemiological investigations.

  15. Site-specific, insertional inactivation of incA in Chlamydia trachomatis using a group II intron.

    Science.gov (United States)

    Johnson, Cayla M; Fisher, Derek J

    2013-01-01

    Chlamydia trachomatis is an obligate, intracellular bacterial pathogen that has until more recently remained recalcitrant to genetic manipulation. However, the field still remains hindered by the absence of tools to create selectable, targeted chromosomal mutations. Previous work with mobile group II introns demonstrated that they can be retargeted by altering DNA sequences within the intron's substrate recognition region to create site-specific gene insertions. This platform (marketed as TargeTron™, Sigma) has been successfully employed in a variety of bacteria. We subsequently modified TargeTron™ for use in C. trachomatis and as proof of principle used our system to insertionally inactivate incA, a chromosomal gene encoding a protein required for homotypic fusion of chlamydial inclusions. C. trachomatis incA::GII(bla) mutants were selected with ampicillin and plaque purified clones were then isolated for genotypic and phenotypic analysis. PCR, Southern blotting, and DNA sequencing verified proper GII(bla) insertion, while continuous passaging in the absence of selection demonstrated that the insertion was stable. As seen with naturally occurring IncA(-) mutants, light and immunofluorescence microscopy confirmed the presence of non-fusogenic inclusions in cells infected with the incA::GII(bla) mutants at a multiplicity of infection greater than one. Lack of IncA production by mutant clones was further confirmed by Western blotting. Ultimately, the ease of retargeting the intron, ability to select for mutants, and intron stability in the absence of selection makes this method a powerful addition to the growing chlamydial molecular toolbox.

  16. Tres documentos inéditos para la historia de la guerra de reconquista inca

    Directory of Open Access Journals (Sweden)

    1984-01-01

    Full Text Available Dans cet article sont publiées les déclarations de trois témoins oculaires des événements de 1533 à 1558, c'est-à-dire depuis l'entrée de Manko Inka Yupanki à Cusco, avec ses alliés espagnols, jusqu'à la 'sortie' de l'auki Sayri Thupa, -un de ses enfants- en 1558, sur la pression militaire et diplomatique du Marquis de Cañete. Ces témoignages directs, confrontés avec d'autres contemporains, constituent de nouveaux éléments inédits pour éclairer la version donnée par les sources espagnoles de cette époque ils font connaître également, et presque en détail, les négociations du vice-roi Marquis de Cañete, lequel se proposait d'en finir pacifiquement avec la résistance héroïque de Vilcabamba, ainsi que la prudence Inca pour déjouer ce plan et éviter les dangers d'une guerre contre ce dernier réduit du Tawantinsuyo. Il ressort de ces témoignages, comparés avec d'autres fiables que nous avons consultés, la mise en question de la vérité sur la succession de Sayri Thupa à la mort de son père, Manko Inka, et la possibilité que le jeune auki ait simulé cette fonction par le truchement d'un artifice politique de la Cour de Vilcabamba. Se publican en este artículo las declaraciones de tres testigos presenciales de los sucesos de 1533 a 1558, es decir desde la entrada de Manko Inka Yupanki al Cusco, con sus aliados españoles, hasta la 'salida' del auki Sayri Thupa, -uno de sus hijos- en 1558, ante la presión militar y diplomática del Marqués de Cañete. Estos testimonios directos, confrontados con otros coetáneos, constituyen nuevos e inéditos elementos de juicio para aclarar la versión de las fuentes hispanas de estos años y para conocer casi en detalle las negociaciones del virrey Marqués de Cañete, que se proponía acabar pacíficamente con la resistencia heroica de Vilcabamba, y la cautela Inca para burlar este propósito y evitar los peligros de una guerra contra este último reducto del Tawantinsuyo

  17. Infrared limb sounding of Titan with the Cassini Composite InfraRed Spectrometer: effects of the mid-IR detector spatial responses.

    Science.gov (United States)

    Nixon, Conor A; Teanby, Nicholas A; Calcutt, Simon B; Aslam, Shahid; Jennings, Donald E; Kunde, Virgil G; Flasar, F Michael; Irwin, Patrick G; Taylor, Fredric W; Glenar, David A; Smith, Michael D

    2009-04-01

    The composite infrared spectrometer (CIRS) instrument on board the Cassini Saturn orbiter employs two 1x10 HgCdTe detector arrays for mid-infrared remote sensing of Titan's and Saturn's atmospheres. In this paper we show that the real detector spatial response functions, as measured in ground testing before launch, differ significantly from idealized "boxcar" responses. We further show that neglecting this true spatial response function when modeling CIRS spectra can have a significant effect on interpretation of the data, especially in limb-sounding mode, which is frequently used for Titan science. This result has implications not just for CIRS data analysis but for other similar instrumental applications.

  18. Exploring pain in the Andes--learning from the Quichua (Inca) people experience.

    Science.gov (United States)

    Incayawar, Mario; Saucier, Jean-François

    2015-05-01

    There is a mounting recognition that culture profoundly shapes human pain experience. The 28 million indigenous people of the Andes in South America, mainly the Quichua (Inca) people, share a distinctive culture. However, little is known about their pain experience and suffering. The aim of the present study was to explore how Quichua adults perceive, describe, and cope with the pain. An exploratory qualitative/descriptive study was conducted with a convenience sample of 40 Quichua adults, including 15 women and 25 men, in the Northern Highlands of Ecuador. Data were collected through structured interviews of approximately 3 h, using a Quichua questionnaire called "The Nature of Pain" [Nanay Jahua Tapuicuna]. The interviews covered the notions of causation of pain, vulnerability to pain, responses to pain, aggravating factors, frequent locations of pain, types of pain, duration, characteristics of pain, control of pain, pathways to care, and preventive measures of pain. Basic descriptive analyses were performed. The Quichuas' pain experience is complex and their strategies to cope with it are sophisticated. According to the Quichuas, emotions, life events, co-morbid conditions, and spirits, among others factors play an important role in the origin, diagnosis, and treatment of pain. They strongly embrace biomedicine and physicians as well as Quichua traditional medicine and traditional healers. Family members and neighbors are also valuable sources of health care and pain control. The pathway to pain care that the Quichua people prefer is inclusive and pluralistic. The knowledge of the Quichua ethnographic "emic" details of their belief system and coping strategies to control pain are clinically useful not only for the health professional working in the Andes, some Quichua cultural characteristics related to pain could be useful to the culturally competent health practitioner who is making efforts to provide high-quality medical care in rural and multicultural

  19. Detecting Immune System Response Proteins in a 500 Year-old Inca Mummy

    Science.gov (United States)

    Corthals, A.; Davalos, L.; Martin, D.W.; Rieger, R.; Chen, E.I.; Koller, A.

    2011-01-01

    Disease detection in ancient human samples currently relies on genomic-based assays, which are error prone due to contamination and cannot distinguish between active and latent pathogenic infection. On the other hand, protein-based assays such as global protein profiling offer complementary alternatives for the pathological diagnosis of archeological specimen. The discovery of three Inca mummies in 1998, perfectly preserved in the permafrost of the high Andes, allowed us to analyze mummy samples by protein-based and genomic-based assay. A buccal swab from one of the 500 year old mummy was analyzed by shotgun proteomics to detect the protein profile. Among the identified proteins, we found a signature of proteins indicating an immune response to a bacterial infection at the time of the mummy's death. Based on the external visible symptoms and the gamut of immune response proteins obtained from the mouth swab, we suspected that the pulmonary infection was caused by Mycobacterium. PCR assay followed by direct sequencing of the PCR products confirmed the presence of Mycobacterium sp. in the mouth swab. Until now, immunoassays have been the only way to detect an active immune response and infer infection in historical samples, but these were plagued by low specificity and sensitivity. However, we demonstrate here the feasibility of incorporating global protein profiling in the diagnosis of infection from archeological samples. Protein signatures obtained from these samples could be extremely useful in determining the status of infection while genomic-based assays can be used to detect the identity of the pathogen.

  20. A despeckle filter for the Cassini SAR images of Titan's surface

    Science.gov (United States)

    Bratsolis, Emmanuel; Solomonidou, Anezina; Bampasidis, Georgios; Le Mouelic, Stephane; Sotin, Christophe; Coustenis, Athena; Moussas, Xenophon; Kyriakopoulos, Konstantinos

    2010-05-01

    Cassini carries a multimode Ku-band (13.78 GHz) radar instrument designed to probe the surface of Titan and that of other targets in the Saturn system in four operating modes: imaging, altimetry, scatterometry, and radiometry. The Synthetic Aperture Radar (SAR) mode is used at altitudes under ~4000 km, resulting in spatial resolution ranging from ~350 m to >1 km. Images are acquired either left or right of nadir using 2-7 looks. A swath 120-450 km wide is created from 5 antenna beams. SAR coverage is dependent on spacecraft range and orbital geometry. Radar backscatter variations in SAR images can be interpreted in terms of variations of surface slope, near-surface roughness, or near-surface dielectric properties. The images obtained using SAR revealed that Titan has very complex surface (Elachi et al. 2005). A filtering technique is applied to obtain the restored image. One of the major problems hampering the derivation of meaningful texture information from SAR imagery is the speckle noise. It overlays "real" structures and causes gray value variations even in homogeneous parts of the image. Our method is based on probabilistic methods and regards an image as a random element drawn from a prespecified set of possible images. The TSPR (Total Sum Preserving Regularization) filter used here is based on a membrane model Markov random field approximation with a Gaussian conditional probability density function optimized by a synchronous local iterative method. The final form of despeckling gives a sum-preserving regularization for the pixel values of the image. The TSPR method preserves the mean values of local homogeneous regions and decreases the standard deviation up to six times (Bratsolis and Sigelle, 2003). The despeckle filter can be used as intermediate stage for the extraction of meaningful regions that correspond to structural units in the scene or distinguish objects of interest (Bratsolis, 2009). References E. Bratsolis, and M. Sigelle, "Fast SAR Image

  1. Bathymetry and Composition of Titan's Hydrocarbon Seas from the Cassini RADAR Altimeter

    Science.gov (United States)

    Mastrogiuseppe, Marco; Hayes, Alex; Poggiali, Valerio; Lunine, Jonathan; Seu, Roberto; Hofgartner, Jason; Le Gall, Alice; Lorenz, Ralph

    2016-04-01

    The Cassini RADAR's altimetry mode has been successfully used for probing the depth and composition of Titan's hydrocarbons seas. In May 2013, during the spacecraft's T91 flyby of Titan, the instrument demonstrated its capabilities as a radar sounder, presenting a unique opportunity to constraint the depth and composition of Titan's second largest sea, Ligeia Mare. Later, observations of Kraken Mare and Punga Mare were planned and executed in August 2014 (T104) and January 2015 (T108), respectively. While most of the seafloor was not detected at Kraken, suggesting the sea was either too deep or too absorptive in these areas to observe a return from the seafloor, shallow areas near Moray Sinus did show subsurface reflections. At Punga Mare, a clear detection of the subsurface was observed with a maximum depth of 120 m along the radar altimetry transect. Herein we present a re-analysis of altimetry data acquired over Ligeia Mare and, earlier in the Cassini mission (in December 2008 during T49), over the southern Ontario Lacus. Depths measurements and liquid composition are obtained using a novel technique which makes use of radar simulations and Monte Carlo-based inversions. Simulation is based on a two-layer model, where the surface is represented by a specular reflection and the seafloor is modeled using a facet-based synthetic surface, including thermal noise, speckle effects, analog to digital conversion (ADC), block adaptive quantization (BAQ), and allows for possible receiver saturation. This new analysis provides an update to the Ku-band attenuation (the Cassini RADAR operates at a wavelength of 2 cm) and results in a new estimate for loss tangent and composition. We found a value of specific attenuation of the liquid equal to 0.14±0.02 dB/m and 0.2±0.1 dB/m, which is equivalent to a loss tangent of 4.4±0.9x10^-5 and 7±3x10^-5 for Ligeia Mare and Ontario Lacus, respectively. Assuming that Titan's liquid bodies are composed by a ternary mixture of methane

  2. Cassini SAR, radiometry, scatterometry and altimetry observations of Titan's dune fields

    Science.gov (United States)

    Le, Gall A.; Janssen, M.A.; Wye, L.C.; Hayes, A.G.; Radebaugh, J.; Savage, C.; Zebker, H.; Lorenz, R.D.; Lunine, J.I.; Kirk, R.L.; Lopes, R.M.C.; Wall, S.; Callahan, P.; Stofan, E.R.; Farr, Tom

    2011-01-01

    Large expanses of linear dunes cover Titan's equatorial regions. As the Cassini mission continues, more dune fields are becoming unveiled and examined by the microwave radar in all its modes of operation (SAR, radiometry, scatterometry, altimetry) and with an increasing variety of observational geometries. In this paper, we report on Cassini's radar instrument observations of the dune fields mapped through May 2009 and present our key findings in terms of Titan's geology and climate. We estimate that dune fields cover ???12.5% of Titan's surface, which corresponds to an area of ???10millionkm2, roughly the area of the United States. If dune sand-sized particles are mainly composed of solid organics as suggested by VIMS observations (Cassini Visual and Infrared Mapping Spectrometer) and atmospheric modeling and supported by radiometry data, dune fields are the largest known organic reservoir on Titan. Dune regions are, with the exception of the polar lakes and seas, the least reflective and most emissive features on this moon. Interestingly, we also find a latitudinal dependence in the dune field microwave properties: up to a latitude of ???11??, dune fields tend to become less emissive and brighter as one moves northward. Above ???11?? this trend is reversed. The microwave signatures of the dune regions are thought to be primarily controlled by the interdune proportion (relative to that of the dune), roughness and degree of sand cover. In agreement with radiometry and scatterometry observations, SAR images suggest that the fraction of interdunes increases northward up to a latitude of ???14??. In general, scattering from the subsurface (volume scattering and surface scattering from buried interfaces) makes interdunal regions brighter than the dunes. The observed latitudinal trend may therefore also be partially caused by a gradual thinning of the interdunal sand cover or surrounding sand sheets to the north, thus allowing wave penetration in the underlying

  3. The Calm Methane Northern Seas of Titan from Cassini Radio Science Observations

    Science.gov (United States)

    Marouf, Essam A.; French, Richard G.; Wong, Kwok; Anabtawi, Aseel; Schinder, Paul J.; Cassini Radio Science Team

    2016-10-01

    We report on results from 3 bistatic scattering observations of Titan northern seas conducted by the Cassini spacecraft in 2014 ( flybys T101, T102, and T106). The onboard Radio Science instrument transmits 3 sinusoidal signals of 0.94, 3.6, and 13 cm wavelengths. The spacecraft is continuously maneuvered to point in incidence direction so that mirror-like reflections from Titan's surface are observed at the ground stations of the NASA Deep Space Network. The corresponding ground-track in all 3 cases crossed different regions of Kraken Mare, and in the case of T101 also crossed Ligeia Mare. A nearly pure sinusoidal reflected signal was clearly detectable in the observed echoes spectra over surface regions identified in the Cassini RADAR images as potential liquid regions. Weaker quasi-specular echoes were also evident over some intermediate dry land and near sea shores. Cassini transmits right-circularly-polarized (RCP) signals and both the RCP and LCP echo components are observed. Their spectral shape, bandwidth, and total power are the observables used to infer/constrain physical surface properties. Presented results are limited to the 3.6 cm wavelength signal which has the largest SNR. The remarkably preserved sinusoidal echo spectral shape and the little detectable Doppler broadening strongly suggest surface that is smooth on scales large compared to 3.6 cm. If long wavelength gravity waves are present, they must be very subtle. The measured RCP/LCP echo power ratio provides direct measurement of the surface dielectric constant and is diagnostic of the liquid composition. The power ratio measurements eliminate possible significant ethane contribution and strongly imply predominantly liquid methane and nitrogen composition. Carefully calibrated measurements of the absolute echo power and the inferred dielectric constant constrain the presence of any capillary waves of wavelength << 3.6 cm. The latter affect wave coherence across the Fresnel region, reducing the

  4. Ions in the Enceladus plume: Cassini/CAPS ion measurements at high energy resolution

    Science.gov (United States)

    Crary, F.; Coates, A. J.; Hill, T. W.; Jones, G. H.; Tokar, R. L.

    2012-12-01

    During several Cassini encounters with Saturn's satellite, Enceladus, the spacecraft crossed through the plume of water vapor and dust south of the satellite with a spacecraft orientation which allowed the Cassini Plasma Spectrometer (CAPS) to observe ions and nanograin dust particles associated with the plume. During three of these encounters, E7 (November 2, 2009), E17 (March XX, 2012) and E18 (April YY, 2012), the trajectories were very similar and parallel to the equatorial plane (i.e. little north-south velocity, so that the spacecraft moved perpendicular to the rotation axis of Enceladus.) Previous analysis, using data from the CAPS ion mass spectrometer (IMS) and electron spectrometer (ELS), identified cold ions at rest with respect to Enceladus [1], negative water group and water cluster ions [2], and both positively and negatively charged dust particles in the 0.5 to 2 nm (1000 to 20,000 AMU) size range [3,4]. We present observations from the third CAPS sensor, the ion beam spectrometer (IBS). Although this sensor lacks the angular resolution of the other CAPS sensors, it has an energy resolution of 1.4%, roughly an order of magnitude greater than the ELS and IMS sensors. The IBS data allows us to estimate the temperature and flow speed of the low energy ions in the plume, and characterize the structure of the plume ionosphere. We find that the plume is highly structured, down to the 2-s (17 km along track) limit of the instrument's sampling. Distinct regions of cold, dense ions, resembling a collisional ionosphere, are intermixed with a broad background of warmer, non-thermal ions, possibly resulting from charge exchange between magnetospheric ions and plume neutrals. Despite the sensor's lack of intrinsic angular resolution, the ion flux and energy spectra are consistent with a drift velocity away from Saturn and in the direction of the upstream flow. References: [1] Tokar et al., 2009, Cassini detection of Enceladus' cold water-group plume ionosphere

  5. La episteme renacentista en la primera parte de los Comentarios reales: del Inca Garcilaso de la Vega

    OpenAIRE

    Guerra Caminiti, Estrella

    2012-01-01

    Teniendo como marco lo expuesto por Michel Foucault en su libro Las palabras y las cosas sobre la episteme renacentista, nos interesa explorar cómo la primera parte de los Comentarios reales son una expresión de lo planteado por Foucault. No es gratuito que la crónica del Inca Garcilaso se titule precisamente Comentarios y que Foucault señale que el comentario permite que el lenguaje refiera al lenguaje y, gracias a él, la construcción de un discurso segundo a partir del que se interpreta el ...

  6. La vida pública de un príncipe inca residente en Quito, siglos XV y XVI

    Directory of Open Access Journals (Sweden)

    1978-01-01

    Full Text Available Ce texte relate la vie et les actions d'un prince inca, originaire du Cuzco, qui par décision des derniers souverains de l'Empire avait d’importantes charges administratives et politiques dans le royaume de Quito. Est joint à ce texte une information inédite de 1562 où l'on découvre que de telles personnes jouissaient de la concession de petites propriétés de type féodal, qui incluait la propriété des terres travaillées par les yanaconas et considérées comme leurs biens propres par ces nobles. De même, il est expliqué comment cette noblesse indigène s'est adaptée à la machine coloniale espagnole afin de ne pas perdre ses privilèges. Se refiere aquí a la vida y hechos de un príncipe inca, oriundo del Cuzco, que por disposición de los últimos soberanos del imperio desempeñó altos cargos administrativos y políticos en el reino de Quito. Se acompaña el texto de una información inédita de 1562, bastante notable debido a que descubre que tales personajes gozaban de la concesión de pequeños feudos, que incluía la propiedad de tierras trabajadas por yanaconas que dichos nobles consideraban como suyos. También se refiere cómo esta nobleza indígena pasó a acomodarse en la maquinaria colonial española para no perder sus privilegios señoriales. This text describes the life and activities of an Inca prince, originally from Cuzco, who, by order of the last rulers of the Inca Empire, had been charged with important administrative and political responsibilities in the Kingdom of Quito. The text is accompanied by an unpublished document dating from 1562 which is of considerable interest since it reveals that personalities such as this prince were privileged by the concession of small, feudal - type properties, which also included the ownership of land worked by yanaconas who were considered by these nobles as being part of their personal property. The document also refers to the way in which this native nobility went on to

  7. Cassini Orbit Determination Performance (July 2008 - December 2011)

    Science.gov (United States)

    Pelletier, Frederic J.; Antreasian, Peter; Ardalan, Shadan; Buffington, Brent; Criddle, Kevin; Ionasescu, Rodica; Jacobson, Robert; Jones, Jeremy; Nandi, Sumita; Nolet, Simon; hide

    2012-01-01

    This paper reports on the orbit determination performance for the Cassini spacecraft from July 2008 to December 2011. During this period, Cassini made 85 revolutions around Saturn and had 52 close satellite encounters. 35 of those were with the massive Titan, 13 with the small, yet interesting, Enceladus as well as 2 with Rhea and 2 with Dione. The period also includes 4 double encounters, where engineers had to plan the trajectory for two close satellite encounters within days of each other at once. Navigation performance is characterized by ephemeris errors relative to in-flight predictions. Most Titan encounters 3-dimensional results are within a 1.5 formal sigma, with a few exceptions, mostly attributable to larger maneuver execution errors. Results for almost all other satellite encounter reconstructions are less than 3 sigma from their predictions. The errors are attributable to satellite ephemerides errors and in some cases to maneuver execution errors.

  8. Cassini/CAPS Observations of Tail Dynamics at Saturn

    Science.gov (United States)

    Thomsen, M. F.; Tokar, R. L.; Wilson, R. J.; Jackman, C. M.

    2013-12-01

    Following up a recent study of the density and flow direction of plasmas in Saturn's premidnight tail, we apply the same methodology to examine Cassini's near- and post-midnight tail passes as well. Specifically, we focus on intervals when CAPS was able to view both inward and outward plasma flows, and we examine the spatial distribution and other properties of such flows. We compare our results with those found by McAndrews et al. [Plasma in Saturn's nightside magnetosphere and the implications for global circulation, Plan. Sp. Sci. (2009)], using a different approach to the analysis of Cassini/CAPS data. These observations provide important clues to Saturn's tail structure and dynamics.

  9. The formation of the Cassini division in Saturn's rings

    Science.gov (United States)

    Goldreich, P.; Tremaine, S.

    1978-01-01

    An explanation for the size and location of the Cassini division in Saturn's rings is proposed. The explanation is based on the collective response of the particles in the ring to the resonant forcing by Mimas. An upper limit is calculated for the width of the gap that could be opened at a resonance. In addition, an estimate is obtained regarding the damping of the density waves by viscous and nonlinear effects. A picture is presented of the development of a gap. The results are compared with the observed properties of the divisions in Saturn's rings. The exact position of the inner edge of the Cassini division is difficult to predict, because the 2:1 resonance lies very near several weaker resonances (4:2 and 6:3 with Mimas, 4:1 with Tethys). However, the edge should lie near 17 seconds, and this is consistent with ground based observations.

  10. Radiation Transport of Heliospheric Lyman-alpha from Combined Cassini and Voyager Data Sets

    Science.gov (United States)

    Pryor, W.; Gangopadhyay, P.; Sandel, B.; Forrester, T.; Quemerais, E.; Moebius, E.; Esposito, L.; Stewart, I.; McClintock, W.; Jouchoux, A.; hide

    2008-01-01

    Heliospheric neutral hydrogen scatters solar Lyman-alpha radiation from the Sun with '27-day' intensity modulations observed near Earth due to the Sun's rotation combined with Earth's orbital motion. These modulations are increasingly damped in amplitude at larger distances from the Sun due to multiple scattering in the heliosphere, providing a diagnostic of the interplanetary neutral hydrogen density independent of instrument calibration. This paper presents Cassini data from 2003-2004 obtained downwind near Saturn at approximately 10 AU that at times show undamped '27-day' waves in good agreement with the single-scattering models of Pryor et al., 1992. Simultaneous Voyager 1 data from 2003- 2004 obtained upwind at a distance of 88.8-92.6 AU from the Sun show waves damped by a factor of -0.21. The observed degree of damping is interpreted in terms of Monte Carlo multiple-scattering calculations (e.g., Keller et al., 1981) applied to two heliospheric hydrogen two-shock density distributions (discussed in Gangopadhyay et al., 2006) calculated in the frame of the Baranov-Malama model of the solar wind interaction with the two-component (neutral hydrogen and plasma) interstellar wind (Baranov and Malama 1993, Izmodenov et al., 2001, Baranov and Izmodenov, 2006). We conclude that multiple scattering is definitely occurring in the outer heliosphere. Both models compare favorably to the data, using heliospheric neutral H densities at the termination shock of 0.085 cm(exp -3) and 0.095 cm(exp -3). This work generally agrees with earlier discussions of Voyager data in Quemerais et al., 1996 showing the importance of multiple scattering but is based on Voyager data obtained at larger distances from the Sun (with larger damping) simultaneously with Cassini data obtained closer to the Sun.

  11. Overview of Cassini radio science at Saturn, Titan, and the icy satellites

    Science.gov (United States)

    Kliore, A. J.; Ambrosini, R.; Armstrong, J. W.; Flasar, F. M.; French, R. G.; Iess, L.; Marouf, E. A..; Nagy, A. F.; Rappaport, N. J.; Tortora, P.; Jpl/Dsn Radio Science Support Team

    The Cassini spacecraft which has been in orbit about Saturn for over two years is the first Radio Science platform to provide three downlink frequencies In addition to the X-band telemetry link 3 56 cm w l two other frequencies S-band 13 04 cm and Ka-band 0 94 cm are available This plus the high SNR 50 dBHz at X-band afforded by the 4 m diameter s c high gain antenna in combination with the excellent low noise receivers of the DSN as well as overall system stabilities of 1 part in 10 13 when referenced to the on-board ultra-stable oscillator USO in one-way operation and 1 part inx 10 15 for a two-way link make Cassini an unprecedented instrument of radio science The orbital tour phase of the mission has the following main radio science objectives a determination of the masses and gravity fields of Saturn s icy satellites Titan and Saturn through two-way tracking during fly-bys To date the masses of Phoebe Iapetus Dione Enceladus Rhea and Titan have been measured and will be reported here b Measurement of the structure and other properties of Saturn s rings through three-band occultation Seven near-diametric occultations at a high ring opening angle have been completed and the results will be presented here c Measurement of the vertical structure of the atmosphere and ionosphere of Saturn The same series of occultations have provided nearly equatorial observations of the atmosphere structure and the ionosphere and the results will be described here d Measurement of the vertical structure of

  12. Improving the Planetary Ephemeris with Astrometric Observations of Cassini

    Science.gov (United States)

    Jones, Dayton L.; Fomalont, E.; Dhawan, V.; Romney, J.; Lanyi, G.; Border, J.; Folkner, B.; Jacobson, B.

    2009-05-01

    During the past three years we have carried out a series of astrometric VLBA observations of the Cassini spacecraft. At each epoch, we used phase referencing to obtain high precision relative positions between Cassini and an angularly nearby calibration source. The calibration sources were separately tied to nearby defining sources of the International Celestial Reference Frame (ICRF) through additional phase-referenced VLBA experiments. By combining our position measurements of Cassini with a model of Cassini's orbit around Saturn (from Doppler measurements by the Deep Space Network), we are able to determine the ICRF position of Saturn at each epoch to about 0.3 mas. This is about 2 km at the average distance of Saturn. These results will improve the Saturn ephemeris, particularly in ecliptic latitude (the plane of Saturn's orbit). The error in latitude decreases dramatically as the total time span of VLBA data approaches 1/4 of Saturn's orbital period in 2011-2012. Saturn is the first outer planet whose ephemeris can be improved and more closely tied to the ICRF and the inner solar system through long-term observations of an orbiter. The planned Juno mission to Jupiter will allow this technique to be applied there also. The planetary ephemeris is an essential tool for studies of solar system dynamics, interplanetary spacecraft navigation, and test of general relativity. It requires continuous maintenance and improvement. This research has been carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration, and has relied on observations by the Very Long Baseline Array, a facility of the National Science Foundation operated by the National Radio Astronomy Observatory under a cooperative agreement with Associated Universities, Inc.

  13. Design and Analysis of RTGs for CRAF and Cassini Missions

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred; Noravian, Heros; Or, Chuen; Sankarankandath, Kumar

    1991-01-01

    The design and analysis of Radioisotope Thermoelectric Generators integrated with JPL's CRAF and Cassini spacecraft are described. The principal purposed of the CRAF mission are the study of asteroids and comets, and the principal purposes of the Cassini mission are the study of asteroids, Saturn, and its moons (particularly Titan). Both missions will employ the Mariner/Mark-2 spacecraft, and each will be powered by two GPHS-RTGs. JPL's spacecraft designers wish to locate the two RTGs in close proximity to each other, resulting in mutual and unsymmetrical obstruction of their heat rejection paths. To support JPL's design studies, the U.S. Department of Energy asked Fairchild to determine the effect of the RTGs' proximity on their power output. This required the development of novel analysis methods and computer codes, described in this report, for the coupled thermal and electrical analysis of obstructed RTGs with axial and circumferential temperature, voltage, and current variations. The code was validated against measured data of unobstructed RTG tests, and was used for the detailed analysis of the obstructed CRAF/Cassini RTGs. Also described is a new method for predicting the combined effect of fuel decay and thermoelectric degradation on the output of obstructed RTGs, which accounts for the effect of diminishing temperatures on degradation rates. The computed results indicate that for the 24-degree separation angle of JPL's baseline design, the mutually obstructed standard GPHS/RTGs show adequate power margins for the CRAF mission, but slightly negative margins for the Cassini mission.

  14. 基于 S12 XE 的嵌入式系统利用 INCA 实现 CCP 标定%The Realization of CCP Calibration Using INCA on the Embedded System with S12 XE

    Institute of Scientific and Technical Information of China (English)

    苏万樯; 谢小娟

    2014-01-01

    The basic principle of CCP protocol , calibration tool INCA and the architecture of CCP function is introduced in the arti-cle.The method of the realization of CCP calibration on the embedded system with S 12XE is described.The seamless integration be-tween the developed embedded system and the main stream calibration tool INCA is realized by writing the suitable A 2L file.The de-velopment result shows that this method can realize the CCP calibration on the embedded system with S 12 XE by using the powerful functions of the existing calibration tool .%介绍了CCP协议的基本原理、标定工具INCA及CCP标定的整体架构。提出了在基于S12 XE的嵌入式系统上实现CCP标定功能的方法,通过编写合适的A2L文件,实现了所开发的系统与业界主流的标定工具INCA的无缝集成。开发结果表明,这种方法能够利用现有标定工具的强大功能,快速可靠地实现S12XE的嵌入式系统的CCP在线标定功能,大大节约开发周期。

  15. Cassini at Saturn Proximal Orbits - Attitude Control Challenges

    Science.gov (United States)

    Burk, Thomas A.

    2013-01-01

    The Cassini mission at Saturn will come to an end in the spring and summer of 2017 with a series of 22 orbits that will dip inside the rings of Saturn. These are called proximal orbits and will conclude with spacecraft disposal into the atmosphere of the ringed world on September 15, 2017. These unique orbits that cross the ring plane only a few thousand kilometers above the cloud tops of the planet present new attitude control challenges for the Cassini operations team. Crossing the ring plane so close to the inner edge of the rings means that the Cassini orientation during the crossing will be tailored to protect the sensitive electronics bus of the spacecraft. This orientation will put the sun sensors at some extra risk so this paper discusses how the team prepares for dust hazards. Periapsis is so close to the planet that spacecraft controllability with RCS thrusters needs to be evaluated because of the predicted atmospheric torque near closest approach to Saturn. Radiation during the ring plane crossings will likely trigger single event transients in some attitude control sensors. This paper discusses how the attitude control team deals with radiation hazards. The angular size and unique geometry of the rings and Saturn near periapsis means that star identification will be interrupted and this paper discusses how the safe mode attitude is selected to best deal with these large bright bodies during the proximal orbits.

  16. Cassini at Saturn Proximal Orbits - Attitude Control Challenges

    Science.gov (United States)

    Burk, Thomas A.

    2013-01-01

    The Cassini mission at Saturn will come to an end in the spring and summer of 2017 with a series of 22 orbits that will dip inside the rings of Saturn. These are called proximal orbits and will conclude with spacecraft disposal into the atmosphere of the ringed world on September 15, 2017. These unique orbits that cross the ring plane only a few thousand kilometers above the cloud tops of the planet present new attitude control challenges for the Cassini operations team. Crossing the ring plane so close to the inner edge of the rings means that the Cassini orientation during the crossing will be tailored to protect the sensitive electronics bus of the spacecraft. This orientation will put the sun sensors at some extra risk so this paper discusses how the team prepares for dust hazards. Periapsis is so close to the planet that spacecraft controllability with RCS thrusters needs to be evaluated because of the predicted atmospheric torque near closest approach to Saturn. Radiation during the ring plane crossings will likely trigger single event transients in some attitude control sensors. This paper discusses how the attitude control team deals with radiation hazards. The angular size and unique geometry of the rings and Saturn near periapsis means that star identification will be interrupted and this paper discusses how the safe mode attitude is selected to best deal with these large bright bodies during the proximal orbits.

  17. Avoiding Human Error in Mission Operations: Cassini Flight Experience

    Science.gov (United States)

    Burk, Thomas A.

    2012-01-01

    Operating spacecraft is a never-ending challenge and the risk of human error is ever- present. Many missions have been significantly affected by human error on the part of ground controllers. The Cassini mission at Saturn has not been immune to human error, but Cassini operations engineers use tools and follow processes that find and correct most human errors before they reach the spacecraft. What is needed are skilled engineers with good technical knowledge, good interpersonal communications, quality ground software, regular peer reviews, up-to-date procedures, as well as careful attention to detail and the discipline to test and verify all commands that will be sent to the spacecraft. Two areas of special concern are changes to flight software and response to in-flight anomalies. The Cassini team has a lot of practical experience in all these areas and they have found that well-trained engineers with good tools who follow clear procedures can catch most errors before they get into command sequences to be sent to the spacecraft. Finally, having a robust and fault-tolerant spacecraft that allows ground controllers excellent visibility of its condition is the most important way to ensure human error does not compromise the mission.

  18. Gastrointestinal stromal tumor: analysis of 146 cases of the center of reference of the National Cancer Institute--INCA.

    Science.gov (United States)

    Linhares, Eduardo; Gonçalves, Rinaldo; Valadão, Marcus; Vilhena, Bruno; Herchenhorn, Daniel; Romano, Sergio; Ferreira, Maria Aparecida; Ferreira, Carlos Gil; Ramos, Cintia de Araujo; de Jesus, José Paulo

    2011-01-01

    To evaluate the treatment of GIST in INCA. We conducted a retrospective analysis of all cases of GIST treated at INCA in the period from 1997 to 2009. We analyzed 146 patients with a mean age of 44.5 years and female predominance. The main symptom was abdominal pain. We observed the occurrence of a second primary tumor in 22% of cases and 92% of the immunohistochemistry exams were positive for CD117. The most frequent location was in the stomach and the high-risk group was predominant. Surgery was considered R0 (extensive) in 70% of the cases and the main sites of metastases were liver and peritoneum. Overall survival in two and five years was, respectively, 86% and 59%. There was a significant difference between overall survival (p = 0.29) of the high-risk group versus the other. Our patients presented mainly in the form of high-risk disease, with obvious impact on survival. The use of imatinib improved survival of patients with recurrent and metastatic disease. We should study its use in the setting of adjuvant and neoadjuvant therapy to improve results of the high risk group. The creation of reference centers is a need for the study of rare diseases.

  19. Recombinant 35-kDa inclusion membrane protein IncA as a candidate antigen for serodiagnosis of Chlamydophila pecorum.

    Science.gov (United States)

    Mohamad, Khalil Yousef; Rekiki, Abdessalem; Berri, Mustapha; Rodolakis, Annie

    2010-07-14

    Chlamydophila pecorum strains are commonly found in the intestine and vaginal mucus of asymptomatic ruminants and may therefore induce a positive serological response when the animals are tested for C. abortus. They have also been associated with different pathological diseases in ruminants, swine and koala. The aim of this study was to identify specific C. pecorum immunodominant antigens which could be used in ELISA tests allowing to distinguish between animals infected with C. pecorum and those infected with other chlamydial species. A gene encoding 35-kDa inclusion membrane protein incA of C. pecorum was isolated by immunoscreening of the C. pecorum DNA library using ovine anti-C. pecorum antibodies. The recombinant IncA protein did not react with a murine serum directed against C. abortus but did react with a specific monoclonal antibody of C. pecorum and toward several ovine serum samples obtained after experimental infection with different C. pecorum strains. This protein could be a good candidate for specific diagnosis of C. pecorum infection.

  20. Mapping the Atmospheric and Surface Properties of Titan by the Massive Inversion of Cassini/VIMS Spectra

    Science.gov (United States)

    Maltagliati, Luca; Rodriguez, Sébastien; Appéré, Thomas; Vincendon, Mathieu; Douté, Sylvain; LeMouelic, Stéphane; Rannou, Pascal; Sotin, Christophe; Barnes, Jason W.; Coustenis, Athena; Brown, Robert H.

    2014-11-01

    Since the beginning of the Cassini mission, the imaging spectrometer VIMS has acquired ~40000 hyperspectral images of Titan containing several millions of spectra. Such a huge amount of data cannot be analyzed with a radiative transfer solver like SHDOM because of computational limits. Nevertheless, such a solver is the most suited tool to extract simultaneous information of the atmosphere and the surface of Titan from VIMS datacubes. We have developed a method of analyzing VIMS data that consents to use the power of a RT model without the inconvenience of long computational times, by the creation of look-up tables for different values of the RT model's parameters (geometry of the observation, surface albedo, aerosols opacity). We employ up-to-date information on gaseous spectral coefficients, aerosols’ optical properties and Titan’s climatology. These look-up tables, appropriately interpolated, are then used to minimize the observations and create simultaneous maps of aerosols opacity and of surface albedo (at the wavelengths of Titan’s spectral windows). This method lowers the computational time by a factor of several thousands and thus, for the first time, a truly massive treatment of VIMS data. In this paper we present the results of our method applied to the area of the Huygens landing site and their comparison with the results of other Cassini instruments. We also show the retrieved maps of a region observed multiple times at different Cassini flybys with different observational conditions, as the T13/T17 mosaic of the Atzlan area. The perspectives for atmospheric and surface seasonal monitoring are highlighted.

  1. Simultaneous Mapping of Titan's Atmospheric and Surface Properties Through the Massive Inversion of Cassini/VIMS Data

    Science.gov (United States)

    Rodriguez, S.; Maltagliati, L.; Appéré, T.; Vincendon, M.; Douté, S.; Le Mouelic, S.; Rannou, P.; Sotin, C.; Barnes, J. W.; Coustenis, A.; Brown, R. H.

    2014-12-01

    A radiative transfer solver (i.e. SHDOM) is the most powerful tool to extract simultaneous information of the atmosphere and the surface of Titan from the hyperspectral data of the VIMS imaging spectrometer onboard Cassini. However, the sheer amount of data (~40000 VIMS cubes containing several millions of spectra since the beginning of the mission) makes this approach too demanding in computational time. In our analysis we use a radiative transfer model to create look-up tables for different values of the model's parameters (geometry of the observation, surface albedo, aerosols opacity). We employ up-to-date information on gaseous spectral coefficients, aerosols' optical properties and Titan's climatology. These look-up tables, appropriately interpolated, are then used to minimize the observations and create simultaneous maps of surface albedo at the wavelengths of Titan's spectral windows and of aerosols opacity. This approach allows the gain of a factor of several thousands in computational time and thus, for the first time, a truly massive treatment of VIMS data. This capacity of processing full mapping quickly will consent to monitor closely the global and local seasonal evolution of the atmosphere and the surface. We will present the results of our method applied to some cases of interest. We will analyze several hyperspectral images of the Huygens landing site and show the comparison of our results with observations of other Cassini instruments. We will also investigate regions that have been observed multiple times at different Cassini flybys with different observational conditions, as the T13/T17 mosaic of the Atzlan area. The perspectives for atmospheric and surface seasonal monitoring will be highlighted.

  2. TITAN’S UPPER ATMOSPHERE FROM CASSINI/UVIS SOLAR OCCULTATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Capalbo, Fernando J.; Bénilan, Yves [Laboratoire Inter-Universitaire des Systèmes Atmosphériques (LISA), UMR 7583 du CNRS, Universités Paris Est Créteil (UPEC) and Paris Diderot - UPD, 61 avenue du Général de Gaulle, F-94010, Créteil Cédex (France); Yelle, Roger V.; Koskinen, Tommi T., E-mail: fernando.capalbo@lisa.u-pec.fr [Lunar and Planetary Laboratory, University of Arizona, 1629 E. University Blvd., Tucson, AZ 85721 (United States)

    2015-12-01

    Titan’s atmosphere is composed mainly of molecular nitrogen, methane being the principal trace gas. From the analysis of 8 solar occultations measured by the Extreme Ultraviolet channel of the Ultraviolet Imaging Spectrograph (UVIS) on board Cassini, we derived vertical profiles of N{sub 2} in the range 1100–1600 km and vertical profiles of CH{sub 4} in the range 850–1300 km. The correction of instrument effects and observational effects applied to the data are described. We present CH{sub 4} mole fractions, and average temperatures for the upper atmosphere obtained from the N{sub 2} profiles. The occultations correspond to different times and locations, and an analysis of variability of density and temperature is presented. The temperatures were analyzed as a function of geographical and temporal variables, without finding a clear correlation with any of them, although a trend of decreasing temperature toward the north pole was observed. The globally averaged temperature obtained is (150 ± 1) K. We compared our results from solar occultations with those derived from other UVIS observations, as well as studies performed with other instruments. The observational data we present confirm the atmospheric variability previously observed, add new information to the global picture of Titan’s upper atmosphere composition, variability, and dynamics, and provide new constraints to photochemical models.

  3. La piedra del cielo: algunos aspectos de la educación e iniciación religiosa de los príncipes incas

    Directory of Open Access Journals (Sweden)

    Mariusz S. Ziólkowski

    1984-12-01

    Full Text Available En este arículo el aufor trata de determinar cual fue el caracter específico de la "información" que poseía el Sapan, Inka, esta calidad, le valía su alta posición en la jerarquía religiosa y estatal inca.

  4. Radioisotope instruments

    CERN Document Server

    Cameron, J F; Silverleaf, D J

    1971-01-01

    International Series of Monographs in Nuclear Energy, Volume 107: Radioisotope Instruments, Part 1 focuses on the design and applications of instruments based on the radiation released by radioactive substances. The book first offers information on the physical basis of radioisotope instruments; technical and economic advantages of radioisotope instruments; and radiation hazard. The manuscript then discusses commercial radioisotope instruments, including radiation sources and detectors, computing and control units, and measuring heads. The text describes the applications of radioisotop

  5. Feasibility Study of Two Candidate Reaction Wheel/thruster Hybrid Control Architecture Designs for the Cassini Spacecraft

    Science.gov (United States)

    Macala, Glenn A.; Lee, Allan Y.; Wang, Eric K.

    2012-01-01

    As the first spacecraft to achieve orbit at Saturn in 2004, Cassini has collected science data throughout its four-year prime mission (2004-08), and has since been approved for a first and second extended mission through 2017. Cassini carries a set of three "fixed" reaction wheels and a backup reaction wheel (reaction wheel #4) is mounted on top of an articulable platform. If necessary, this platform could be articulated to orient the backup reaction wheel with the degraded wheel. The reaction wheels are used primarily for attitude control when precise and stable pointing of a science instrument such as the narrow angle camera is required. In 2001-02, reaction wheel #3 exhibited signs of bearing cage instability. As a result, reaction wheel #4 was articulated to align with reaction wheel #3. Beginning in July 2003, Cassini was controlled using wheel #1, #2, and #4. From their first use in the spring of 2000 until today, reaction wheels #1 and #2 have accumulated more than3.5 billions revolutions each. As such, in spite of very carefully management of the wheel spin rates by the mission operation team, there are some observed increases in the drag torque of the wheels' bearings. Hence, the mission operations team must prepare for the contingency scenario in which the reaction wheel #1 (in addition to wheel #3) had degraded. In this hypothetical fault scenario, the two remaining reaction wheels (#2 and #4) will not be able to provide precise and stable three-axis control of the spacecraft. In this study, we evaluate the feasibility of controlling Cassini using the two remaining reaction wheels and four thrusters to meet the science pointing requirements for two key science operational modes: the Optical Remote Sensing and Downlink, Fields, Particles, & Waves operation modes. The performance (e.g., pointing control error, pointing stability, hydrazine consumption rate, etc.) of the hybrid controllers in both operations scenarios will be compared with those achieved

  6. Feasibility Study of Two Candidate Reaction Wheel/thruster Hybrid Control Architecture Designs for the Cassini Spacecraft

    Science.gov (United States)

    Macala, Glenn A.; Lee, Allan Y.; Wang, Eric K.

    2012-01-01

    As the first spacecraft to achieve orbit at Saturn in 2004, Cassini has collected science data throughout its four-year prime mission (2004-08), and has since been approved for a first and second extended mission through 2017. Cassini carries a set of three "fixed" reaction wheels and a backup reaction wheel (reaction wheel #4) is mounted on top of an articulable platform. If necessary, this platform could be articulated to orient the backup reaction wheel with the degraded wheel. The reaction wheels are used primarily for attitude control when precise and stable pointing of a science instrument such as the narrow angle camera is required. In 2001-02, reaction wheel #3 exhibited signs of bearing cage instability. As a result, reaction wheel #4 was articulated to align with reaction wheel #3. Beginning in July 2003, Cassini was controlled using wheel #1, #2, and #4. From their first use in the spring of 2000 until today, reaction wheels #1 and #2 have accumulated more than3.5 billions revolutions each. As such, in spite of very carefully management of the wheel spin rates by the mission operation team, there are some observed increases in the drag torque of the wheels' bearings. Hence, the mission operations team must prepare for the contingency scenario in which the reaction wheel #1 (in addition to wheel #3) had degraded. In this hypothetical fault scenario, the two remaining reaction wheels (#2 and #4) will not be able to provide precise and stable three-axis control of the spacecraft. In this study, we evaluate the feasibility of controlling Cassini using the two remaining reaction wheels and four thrusters to meet the science pointing requirements for two key science operational modes: the Optical Remote Sensing and Downlink, Fields, Particles, & Waves operation modes. The performance (e.g., pointing control error, pointing stability, hydrazine consumption rate, etc.) of the hybrid controllers in both operations scenarios will be compared with those achieved

  7. Hypervelocity impact effect of molecules from Enceladus' plume and Titan's upper atmosphere on NASA's Cassini spectrometer from reactive dynamics simulation.

    Science.gov (United States)

    Jaramillo-Botero, Andres; An, Qi; Cheng, Mu-Jeng; Goddard, William A; Beegle, Luther W; Hodyss, Robert

    2012-11-21

    The NASA/ESA Cassini probe of Saturn analyzed the molecular composition of plumes emanating from one of its moons, Enceladus, and the upper atmosphere of another, Titan. However, interpretation of this data is complicated by the hypervelocity (HV) flybys of up to ~18 km/sec that cause substantial molecular fragmentation. To interpret this data we use quantum mechanical based reactive force fields to simulate the HV impact of various molecular species and ice clathrates on oxidized titanium surfaces mimicking those in Cassini's neutral and ion mass spectrometer (INMS). The predicted velocity dependent fragmentation patterns and composition mixing ratios agree with INMS data providing the means for identifying the molecules in the plume. We used our simulations to predict the surface damage from the HV impacts on the INMS interior walls, which we suggest acts as a titanium sublimation pump that could alter the instrument's readings. These results show how the theory can identify chemical events from hypervelocity impacts in space plumes and atmospheres, providing in turn clues to the internal structure of the corresponding sources (e.g., Enceladus). This may be valuable in steering modifications in future missions.

  8. User Guide to the PDS Dataset for the Cassini Composite Infrared Spectrometer (CIRS)

    Science.gov (United States)

    Nixon, Conor A.; Kaelberer, Monte S.; Gorius, Nicolas

    2012-01-01

    This User Guide to the Cassini Composite Infrared Spectrometer (CIRS) has been written with two communities in mind. First and foremost, scientists external to the Cassini Project who seek to use the CIRS data as archived in the Planetary Data System (PDS). In addition, it is intended to be a comprehensive reference guide for those internal to the CIRS team.

  9. Cassini VIMS and RADAR investigation of Titan's equatorial regions: a case for changes in surface properties

    Science.gov (United States)

    Solomonidou, Anezina; Coustenis, Athena; Lopes, Rosaly M. C.; Rodriguez, Sebastien; Hirtzig, Mathieu; Malaska, Michael; Stephan, Katrin; Sotin, Christophe; Drossart, Pierre; Jaumann, Ralf; Bratsolis, Emmanuel; Le Mouélic, Stephane; Brown, Robert H.

    2015-04-01

    The Cassini-Huygens instruments revealed that Titan, Saturn's largest moon, has - in many aspects - a complex, dynamic and Earth-like surface [1;2;3]. Understanding the distribution and interplay of geologic processes on Titan is important for constraining models of its interior, surface-atmosphere interactions, and climate evolution. Data from the remote sensing instruments have shown the presence of diverse terrains, suggesting exogenic and endogenic processes, whose composition remains largely unknown. Interpreting surface features further requires precise knowledge of the contribution by the dense intervening atmosphere, especially the troposphere, which can be recovered from near-IR data such as those collected by Cassini's Visual and Infrared Mapping Spectrometer (VIMS) collects in the so-called "methane windows". In order to simulate the atmospheric contribution and extract surface information, a statistical tool (PCA) and a radiative transfer code are applied on certain regions of interest (i.e. possibly geologically varying and suggested in some cases to be cryovolcanic and/or evaporitic in origin) [4;5;7]. We also analyze RADAR despeckled SAR images in terms of morphology [6]. For comparison, we also look at undifferentiated plains and dune fields regions that are not expected to change with time. We find that Tui Regio and Sotra Patera change with time becoming darker and brighter respectively in terms of surface albedo while the plains and the suggested evaporitic areas in the equatorial regions do not present any significant change [5]. The surface brightening of Sotra supports a possible internal rather than exogenic origin. The unchanged surface behavior of the plains supports a sedimentary origin rather than cryovolcanic. Preliminary results on the chemical composition of the changed regions with time are also presented. We therefore suggest that temporal variations of surface albedo (in chemical composition and/or morphology) exist for some areas

  10. E ring dust sources: Implications from Cassini's dust measurements

    Science.gov (United States)

    Spahn, Frank; Albers, Nicole; Hörning, Marcel; Kempf, Sascha; Krivov, Alexander V.; Makuch, Martin; Schmidt, Jürgen; Seiß, Martin; Miodrag Sremčević

    2006-08-01

    The Enceladus flybys of the Cassini spacecraft are changing our understanding of the origin and sustainment of Saturn's E ring. Surprisingly, beyond the widely accepted dust production caused by micrometeoroid impacts onto the atmosphereless satellites (the impactor-ejecta process), geophysical activities have been detected at the south pole of Enceladus, providing an additional, efficient dust source. The dust detector data obtained during the flyby E11 are used to identify the amount of dust produced in the impactor-ejecta process and to improve related modeling [Spahn, F., Schmidt, J., Albers, N., Hörning, M., Makuch, M., Seiß, M., Kempf, S., Srama, R., Dikarev, V.V., Helfert, S., Moragas-Klostermeyer, G., Krivov, A.V., Sremčević, M., Tuzzolino, A., Economou, T., Grün, E., 2006. Cassini dust measurements at Enceladus: implications for Saturn's E ring. Science, in press]. With this, we estimate the impact-generated dust contributions of the other E ring satellites and find significant differences in the dust ejection efficiency by two projectile families - the E ring particles (ERPs) and the interplanetary dust particles (IDPs). Together with the Enceladus south-pole source, the ERP impacts play a crucial role in the inner region, whereas the IDP impacts dominate the particle production in the outer E ring, possibly accounting for its large radial extent. Our results can be verified in future Cassini flybys of the E ring satellites. In this way poorly known parameters of the dust particle production in hypervelocity impacts can be constrained by comparison of the data and theory.

  11. The Saturnian satellite Rhea as seen by Cassini VIMS

    Science.gov (United States)

    Stephan, K.; Jaumann, R.; Wagner, R.; Clark, R.N.; Cruikshank, D.P.; Giese, B.; Hibbitts, C.A.; Roatsch, T.; Matz, K.-D.; Brown, R.H.; Filacchione, G.; Cappacioni, F.; Scholten, F.; Buratti, B.J.; Hansen, G.B.; Nicholson, P.D.; Baines, K.H.; Nelson, R.M.; Matson, D.L.

    2012-01-01

    Since the arrival of the Cassini spacecraft at Saturn in June 2004, the Visual and Infrared Mapping Spectrometer has obtained new spectral data of the icy satellites of Saturn in the spectral range from 0.35 to 5.2 ??m. Numerous flybys were performed at Saturn's second largest satellite Rhea, providing a nearly complete coverage with pixel-ground resolutions sufficient to analyze variations of spectral properties across Rhea's surface in detail. We present an overview of the VIMS observations obtained so far, as well as the analysis of the spectral properties identified in the VIMS spectra and their variations across its surface compared with spatially highly resolved Cassini ISS images and digital elevation models. Spectral variations measured across Rhea's surface are similar to the variations observed in the VIMS observations of its neighbor Dione, implying similar processes causing or at least inducing their occurrence. Thus, magnetospheric particles and dust impacting onto the trailing hemisphere appear to be responsible for the concentration of dark rocky/organic material and minor amounts of CO 2 in the cratered terrain on the trailing hemisphere. Despite the prominent spectral signatures of Rhea's fresh impact crater Inktomi, radiation effects were identified that also affect the H 2O ice-rich cratered terrain of the leading hemisphere. The concentration of H 2O ice in the vicinity of steep tectonic scarps near 270??W and geologically fresh impact craters implies that Rhea exhibits an icy crust at least in the upper few kilometers. Despite the evidence for past tectonic events, no indications of recent endogenically powered processes could be identified in the Cassini data. ?? 2011 Elsevier Ltd. All rights reserved.

  12. The determination of Dione's gravity field after four Cassini flybys

    Science.gov (United States)

    Zannoni, Marco; Tortora, Paolo; Iess, Luciano; Jacobson, Robert A.; Armstrong, John W.; Asmar, Sami W.

    2015-04-01

    We present the expected accuracy in the determination of Dione's gravity field obtained through numerical simulations of all radio science flybys currently planned in the entire Cassini mission. During its tour of the Saturn system, Cassini already performed two flybys of Dione dedicated to the determination of its mass and gravity field, in October 2005 and December 2011, respectively. Two additional radio science flybys are planned in June 2015 and August 2015. The analysis of the Doppler data acquired during the closest approach of the second flyby allowed the first estimation of Dione's J2 and C22 but, given the limited amount of data, their estimation has a large correlation and cannot be considered fully reliable. Here we infer the expected final accuracy in the determination of Dione's J2 and C22 by combining the available results from the already performed experiments with numerical simulations of future flybys. The main observables considered in the analysis are two-way and three-way Doppler data obtained from the frequency shift of a highly stable microwave carrier between the spacecraft and the stations of NASA's Deep Space Network. White Gaussian noise was added to the simulated data, with a constant standard deviation for each tracking pass, obtained from an accurate noise budget of the Cassini mission. For the two flybys to be carried out in 2015, we consider a continuous coverage during +/-18 hours around the closest approach, plus one tracking pass 36 hours before and after it. The data analysis is carried out using a global, multi-arc fit, and comparing the independent solutions obtained from each flyby and different multi-arc solutions. The analysis of all four flybys is expected to provide the best, unconstrained, reliable estimation of the full quadrupole gravity field of Dione.

  13. Microwave absorptivity in the Saturn atmosphere from Cassini Radio Science

    Science.gov (United States)

    Kliore, A. J.; Marouf, E. A.; Flasar, F. M.

    2011-12-01

    Since 2005, the Cassini spacecraft has collected data from numerous radio occultations by the atmosphere of Saturn. These occultations probed a wide range of latitudes, ranging from equatorial to near-polar. The radio system of Cassini transmits three coherent downlinks to Earth at S-Band (13.04 cm), X-Band (3.56 cm), and Ka-Band (0.94 cm) wavelengths. With the Deep Space Net 70 m receiving stations, The signal-to-noise ratio (SNR) is approximately 48 dB at X-Band, and 38 dB at S-band. At Ka-band, 34 m DSN stations are used, resulting in an SNR of about 41 dB. These SNRs are quite adequate to follow the signals through the top of the microwave-absorbing regions before the noise-floor is reached. By subtracting the refractive defocusing attenuation in the atmosphere (derived from the phase data) from the total attenuation, one obtains the attenuation due to absorption (dB0, which can then be inverted to obtain vertical profiles of absorptivity (dB km-1 ) at each of the three wavelengths. Preliminary results show the expected large effect of wavelength on the absorptivity profiles, with the shorter wavelength signals being absorbed higher in the atmosphere. These profiles can be used to estimate the vertical density profiles of known microwave absorbers, such as NH3 and PH3, examples of which are presented .This work was performed at the Jet Propulsion Laboratory, California Institute of Technology, San Jose State University, and NASA Goddard Space Flight Center with support from the Cassini program.

  14. Destabilization of IncA and IncC plasmids by SGI1 and SGI2 type Salmonella genomic islands.

    Science.gov (United States)

    Harmer, Christopher J; Hamidian, Mohammad; Ambrose, Stephanie J; Hall, Ruth M

    Both the Salmonella genomic islands (SGI) and the conjugative IncC plasmids are known to contribute substantially to the acquisition of resistance to multiple antibiotics, and plasmids in the A/C group are known to mobilize the Salmonella genomic island SGI1, which also carries multiple antibiotic resistance genes. Plasmid pRMH760 (IncC; A/C2) was shown to mobilize SGI1 variants SGI1-I, SGI1-F, SGI1-K and SGI2 from Salmonella enterica to Escherichia coli where it was integrated at the preferred location, at the end of the trmE (thdF) gene. The plasmid was transferred at a similar frequency. However, we observed that co-transfer of the SGI and the plasmid was rarer. In E. coli to E. coli transfer, the frequency of transfer of the IncC plasmid pRMH760 was at least 1000-fold lower when the donor carried SGI1-I or SGI1-K, indicating that the SGI suppresses transfer of the plasmid. In addition, pRMH760 was rapidly lost from both E. coli and S. enterica strains that also carried SGI1-I, SGI1-F or SGI2. However, plasmid loss was not seen when the SGI1 variant was SGI1-K, which lacks two segments of the SGI1 backbone. The complete sequence of the SGI1-I and SGI1-F were determined and SGI1-K also carries two single base substitutions relative to SGI1-I. The IncA (A/C1) plasmid RA1 was also shown to mobilize SGI2-A and though there are significant differences between the backbones of IncA and IncC plasmids, RA1 was also rapidly lost when SGI2-A was present in the same cell. We conclude that there are multiple interactions, both cooperative and antagonistic, between an IncA or IncC plasmid and the SGI1 and SGI2 family genomic islands. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Optical navigation planning process for the Cassini Solstice Mission

    Science.gov (United States)

    Nolet, Simon; Gillam, Stephen D.; Jones, Jeremy B.

    2011-01-01

    During the Cassini Equinox Mission, the Optical Navigation strategy has gradually evolved toward maintenance of an acceptable level of uncertainty on the positions of the bodies to be observed. By counteracting the runoff of the uncertainty over time, this strategy helps satisfy the spacecraft pointing requirements throughout the Solstice Mission, while considerably reducing the required imaging frequency. Requirements for planning observations were established, and the planning process itself was largely automated to facilitate re-planning if it becomes necessary. This paper summarizes the process leading to the optical navigation schedule for the seven years of the Solstice Mission.

  16. Health physics innovations developed during Cassini for future space applications

    Science.gov (United States)

    Nickell, Rod; Rutherford, Theresa; Marmaro, George

    1999-01-01

    There has been a long history of space missions involving Space Nuclear Auxiliary Power (SNAP) devices starting with the Transit 4A Spacecraft (1961), on through the Apollo, Pioneer, Viking, Voyager, Galileo, Ulysses, Mars Pathfinder, and most recently, Cassini (1997). All of these Major Radiological Source (MRS) missions were processed at the Kennedy Space Center/Cape Canaveral Air Station (KSC/CCAS) Launch Site in full compliance with program and regulatory requirements. The cumulative experience gained supporting these past missions has led to significant innovations which will be useful for bench-marking future MRS ground processing.

  17. Optical navigation planning process for the Cassini Solstice Mission

    Science.gov (United States)

    Nolet, Simon; Gillam, Stephen D.; Jones, Jeremy B.

    2011-01-01

    During the Cassini Equinox Mission, the Optical Navigation strategy has gradually evolved toward maintenance of an acceptable level of uncertainty on the positions of the bodies to be observed. By counteracting the runoff of the uncertainty over time, this strategy helps satisfy the spacecraft pointing requirements throughout the Solstice Mission, while considerably reducing the required imaging frequency. Requirements for planning observations were established, and the planning process itself was largely automated to facilitate re-planning if it becomes necessary. This paper summarizes the process leading to the optical navigation schedule for the seven years of the Solstice Mission.

  18. Lightweight Radioisotope Heater Unit (LWRHU) production for the Cassini mission

    Energy Technology Data Exchange (ETDEWEB)

    Rinehart, G.H.

    1996-06-01

    The Lightweight Radioisotope Heater Unit (LWRHU) is a {sup 238}PuO{sub 2} fueled heat source designed to provide a thermal watt of power for space missions. The LWRHU will be used to maintain the temperature of various components on the spacecraft at the required level. The heat source consists of a {sup 238}PuO{sub 2} fuel pellet, a Pt-30Rh capsule, a pyrolytic graphite insulator, and a woven graphite aeroshell assembly. Los Alamos has fabricated 180 heater units, which will be used on the Cassini mission. This report summarizes the specifications, fabrication processes, and production data for the heat sources fabricated at Los Alamos.

  19. Titan's Complex Neutral Composition as Measured by Cassini INMS

    Science.gov (United States)

    Waite, J. H.; Magee, B. A.; Gell, D. A.; Kasprzak, W. T.; Cravens, T.; Vuitton, V. S.; Yelle, R. V.

    2006-12-01

    The composition of Titan's complex neutral atmosphere above 1000 km as observed by the Cassini Ion Neutral Mass Spectrometer on recent flybys of Titan are presented. A rich mixture of hydrocarbons and nitriles are found with mixing ratios that vary from 10-4 to 10-7: acetylene, ethylene, ethane, benzene, toluene, cyanogen, propyne, propene, propane, and various nitriles. The calibration and mass deconvolution processes are presented in order to establish clear boundaries on the systematic errors that can occur in the mass deconvolution process. The role of ion neutral chemistry in forming these compounds will also be discussed.

  20. Flight Path Control Design for the Cassini Solstice Mission

    Science.gov (United States)

    Ballard, Christopher G.; Ionasescu, Rodica

    2011-01-01

    The Cassini spacecraft has been in orbit around Saturn for just over 7 years, with a planned 7-year extension, called the Solstice Mission, which started on September 27, 2010. The Solstice Mission includes 205 maneuvers and 70 flybys which consist of the moons Titan, Enceladus, Dione, and Rhea. This mission is designed to use all available propellant with a statistical margin averaging 0.6 m/s per encounter, and the work done to prove and ensure the viability of this margin is highlighted in this paper.

  1. Micromamiferos andinos holocenicos del sitio arqueologico Inca Cueva 5, Ju Juy, Argentina: tafonomia, zoogeografia y reconstruccion paleoambiental

    Directory of Open Access Journals (Sweden)

    Ortiz, P. E.

    2002-08-01

    Full Text Available A micromammal archaeological sequence (2120 f 120 to 780 f 100 years BP from Inca Cueva 5 site (23" 05' S - 65" 27' W; 3700 m.a.s.l., Jujuy Province, Argentina was studied. The following mammalian taxa were recorded: Order Didelphimorphia, Family Didelphidae, Thylamys cf. T. pallidior; Order Rodentia, Family Muridae, Akodon cf. A. albiventer, Andinomys edax, Auliscomys sublimis, Calomys lepidus, Neotomys ebriosus, Phyllotis sp.; Family Caviidae, Cavia cf. C. tschudii, Galea musteloides; Family Abrocomidae, Abrocoma cinerea; Family Chinchillidae, Lagidium viscacia; Family Octodontidae, Octodontomys gliroides. The taphonomy indicates that the sequence is an owl pellet accumulation inside the cave. The general landscape corresponds to the oriental border of the Puna steppe, with scattered shrub and low brush vegetation. Near the site there are small tree groups of Polylepis australis as well as small streams covered with grass and ciperaceous vegetation known as «vegas». Al1 the recorded taxa at Inca Cueva 5 exist today in Puna and Prepuna environments from Jujuy and Salta Provinces and southem Bolivia, excepting Cavia cf. C. tschudii. The modem records of this species in northem Argentina and southern Bolivia come from localities with high montane bunchgrass prairies and forests of the humid Yungas phytogeographical region. The presence of this species in the sequence suggests wetter climatic conditions on this region when the archaeological site was originated. Later drier conditions, caused probably by anthropic influence in the last 500 years, produced the retraction of Cavia tschudii to the moist eastern side of the Andes and its disappeareance of the Puna areas.El sitio arqueológico Inca Cueva 5 se encuentra en la provincia de Jujuy, Argentina, en el borde oriental de la región de la Puna (23" 05' S - 65" 27' W; 3700 m s n m y está fechado entre 2120 f 120 y 780 f 100 años radiocarbónicos AP. El estudio de una pequeña muestra de

  2. Subduction of the Nazca Ridge and the Inca Plateau: Insights into the formation of ore deposits in Peru [rapid communication

    Science.gov (United States)

    Rosenbaum, Gideon; Giles, David; Saxon, Mark; Betts, Peter G.; Weinberg, Roberto F.; Duboz, Cecile

    2005-10-01

    A large number of ore deposits that formed in the Peruvian Andes during the Miocene (15-5 Ma) are related to the subduction of the Nazca plate beneath the South American plate. Here we show that the spatial and temporal distribution of these deposits correspond with the arrival of relatively buoyant topographic anomalies, namely the Nazca Ridge in central Peru and the now-consumed Inca Plateau in northern Peru, at the subduction zone. Plate reconstruction shows a rapid metallogenic response to the arrival of the topographic anomalies at the subduction trench. This is indicated by clusters of ore deposits situated within the proximity of the laterally migrating zones of ridge subduction. It is accordingly suggested that tectonic changes associated with impingement of the aseismic ridge into the subduction zone may trigger the formation of ore deposits in metallogenically fertile suprasubduction environments.

  3. Inca Rose玫瑰石海鲜餐厅:海鲜爱好者的天堂

    Institute of Scientific and Technical Information of China (English)

    子懿

    2012-01-01

    上海虽然毗邻大海,但食材新鲜的海鲜餐厅却不多久。盛夏刚开张的IncaRose玫瑰石,以其严选食材、品质上乘的海鲜而迅速成为海鲜爱好者们心中的天堂。食客们在此能以480元(三人份)品尝到法国吉拉多生蚝、日本牡丹虾、澳洲小青龙、加拿大红心贝等海鲜拼盘。

  4. Measurements of thermal fission and capture cross sections of minor actinides within the Mini-INCA project

    Energy Technology Data Exchange (ETDEWEB)

    Bringer, O.; Chabod, S.; Dupont, E.; Letourneau, A.; Panebianco, S.; Veyssiere, Ch. [CEA Saclay, Dept. d' Astrophysique de Physique des Particules, de Physique Nucleaire et de l' Instrumentation Associee, 91- Gif sur Yvette (France); Oriol, L. [CEA Cadarache, Dept. d' Etudes des Reacteurs, 13 - Saint Paul lez Durance (France); Chartier, F. [CEA Saclay, Dept. de Physico-Chimie, 91 - Gif sur Yvette (France); Mutti, P. [Institut Laue Langevin, 38 - Grenoble, (France); AlMahamid, I. [Wadsworth Center, New York State Dept. of Health, Albany, NY (United States)

    2008-07-01

    In the framework of nuclear waste transmutation studies, the Mini-INCA project has been initiated at Cea/DSM to determine optimal conditions for transmutation and incineration of Minor Actinides in high intensity neutron fluxes in the thermal region. Our experimental tool is based on alpha- and gamma-spectroscopy of irradiated samples and microscopic fission-chambers. It can provide both microscopic information on nuclear reactions (total and partial cross sections for neutron capture and/or fission reactions) and macroscopic information on transmutation and incineration potentials. The {sup 232}Th, {sup 237}Np, {sup 241}Am, and {sup 244}Cm transmutation chains have been explored in details, showing some discrepancies in comparison with evaluated data libraries but in overall good agreement with recent experimental data. (authors)

  5. Evidence of neurofibromatosis type 1 in a multi-morbid Inca child mummy: A paleoradiological investigation using computed tomography.

    Science.gov (United States)

    Panzer, Stephanie; Wittig, Holger; Zesch, Stephanie; Rosendahl, Wilfried; Blache, Sandra; Müller-Gerbl, Magdalena; Hotz, Gerhard

    2017-01-01

    In this study, an Inca bundle was examined using computed tomography (CT). The primary aim was to determine the preservation status of bony and soft tissues, the sex, the age at the time of death, possible indicators for disease or even the cause of death, as well as the kind of mummification. A secondary aim was to obtain a brief overview of the wrapping in order to gain additional information on the cultural background. The bundle belongs to the Museum of Cultures in Basel, Switzerland, and was bought in Munich, Germany, in 1921. Radiocarbon dating of the superficial textile yielded a calibrated age between 1480 and 1650 AD. The mummy was investigated using multi-slice CT with slice thickness of 0.75 mm and 110 kilovolt. For standardized assessment of soft tissue preservation, a recently developed checklist was applied. CT revealed the mummy of a seven to nine year old boy with superior preservation of bony and soft tissues allowing detailed assessment. Indicators of neurofibromatosis type 1 (paravertebral and cutaneous neurofibromas, a breast neurofibroma, sphenoid wing dysplasia), Chagas disease (dilatation of the esophagus, stomach, rectum, and large amounts of feces), and lung infection (pleural adherence, calcifications), probably due to tuberculosis, were found. Furthermore, signs of peri-mortem violence (transection of the chest and a defect in the abdominal wall) were detected. CT images revealed a carefully performed wrapping. CT examination of the Inca bundle proved to be an important non-destructive examination method. Standardized assessment, especially of the soft tissue structures, allowed for diagnoses of several diseases, indicating a multi-morbid child at the time of death. The careful wrapping pointed to a ceremonial burial. Within the cultural background, the signs of fatal violence were discussed as a possible result of war, murder, accident, or human sacrifice.

  6. Analysis of Cassini UVIS Image Cube Vectors of Enceladus

    Science.gov (United States)

    Shemansky, D. E.; Yoshii, J.; Hansen, Candice; Hendrix, Amanda R.; Liu, X.; Yung, Yuk

    2016-10-01

    Cassini UVIS image cubes of Enceladus from a spacecraft range of image cube matrix discussed here is a virtual 20 X 20 RE structure centered on the satellite body with pixel size 0.2 X 0.2 RE. The pixels are composed of FUV spectral vectors accumulated from multiple exposures by the Cassini experiments in the years 2005 - 2015. In spite of the multiple year exposure, the matrix structure is significantly non-uniform in brightness and spectral content. The features that can be presented at this time are: 1) The pixels at the center of the body show a strong solar reflection that over the 1500 – 1900 A region indicates a spectrally structureless albedo. 2) The central pixels show no discrete emissions other than a weak optically thick atomic hydrogen resonance line (HLya) at 1216 A. 3) Above the limb the solar reflection spectrum appears at irregular locations. One of these is recognized as the south polar plume. The plume solar reflection albedo shows a multiply scattered spectrum dominantly composed of hydrocarbon absorbers, primarily C2H4. 4) Above the limb, the HLya line shows spatially irregular structure with emission peaks in the north 50X brighter than the signal from body center. No discrete emissions other than HLya are observed in the < 2RE region above the limb. The neutral torus at the Enceladus orbit shows only the OI 1304 A line emission. Limits on the presence of other species, H2 in particular, will be presented.

  7. Cassini Thruster Calibration Algorithm Using Reaction Wheel Biasing Data

    Science.gov (United States)

    Rizvi, Farheen

    2012-01-01

    Thrust force estimates for the reaction control thrusters on-board Cassini spacecraft are presented in this paper. Cassini consists of two thruster branches (A and B) each with eight thrusters. The four Z-thrusters control the X and Y-axes, while the four Y-thrusters control the Z-axis. It is important to track the thrust force estimates in order to detect any thruster degradation and for supporting various activities in spacecraft operations (Titan flyby, spacecraft maneuvers). The Euler equation, which describes the rotational motion of the spacecraft during a reaction wheel bias event, is used to develop the algorithm. The thrust estimates are obtained from the pseudo inverse solution using flight telemetry during the bias. Results show that the A-branch Z3A and Z4A thrusters exhibited degraded thrust in November 2008. Due to the degraded thrust performance of Z3A and Z4A, A-branch usage was discontinued and prime branch was swapped to B-branch in March 2009. The thrust estimates from the B-branch do not show any degradation to date. The algorithm is used to trend the B-branch thrust force estimates as the mission continues.

  8. Cassini RPWS Observation of Saturn's Radio Rotation Rates After Equinox

    Science.gov (United States)

    Ye, S.; Fischer, G.; Kurth, W. S.; Gurnett, D. A.

    2015-12-01

    Saturn's radio rotation rate, originally thought to be constant, was found to vary with time by comparing the Voyager and Ulysses observation of Saturn kilometric radiation (SKR). Later on, Cassini RPWS observation of SKR revealed that the two hemispheres of Saturn are rotating at two different rotational periods, and it was proposed that the two periods are subject to seasonal change. The topic we would like to focus on resolving is whether the north and south rotational periods actually crossed after equinox. The almost continuous observation of SKR, Saturn narrowband emission, and auroral hiss by RPWS provide a good method of tracking the radio rotation periods of the planet. SKR power from the northern and southern hemispheres can be separated by the polarization of the radiation. Based on the evolution of SKR phase in the northern and southern hemispheres, we show that the rotation rate of the northern SKR is slower than that of the southern SKR starting from late 2014. Auroral hiss provides another unambiguous method of isolating the rotation signals from one hemisphere because the whistler mode plasma wave cannot cross the equator. Rotational modulation rates of auroral hiss are shown to agree with those of SKR during Cassini's high inclination orbits. Hemispherical origins of the narrowband emission are not distinguishable due to its unique generation mechanism. However, Lomb-Scargle periodogram of the 5 kHz narrowband emissions indicates that the two separate radio rotation periods of Saturn's magnetosphere reappeared after a long break since equinox.

  9. The shape of Saturn's Huygens ringlet viewed by Cassini ISS

    Science.gov (United States)

    Spitale, J. N.; Hahn, J. M.

    2016-11-01

    A new model for the shape of the prominent eccentric ringlet in the gap exterior to Saturn's B ring is developed based on Cassini imaging observations taken over about 8 years. Unlike previous analyses, the new model treats each edge of the ringlet separately. The Keplerian component of the model is consistent with results derived from Voyager observations, and m = 2 modes forced by the nearby Mimas 2:1 Lindblad resonance are seen. Additionally, a free m = 2 mode is seen on the outer edge of the ringlet. Significant irregular structure that cannot be described using normal-mode analysis is seen on the ringlet edges as well. Particularly on the inner edge, that structure remains coherent over multi-year intervals, moving at the local Keplerian rate. We interpret the irregular structure as the signature of embedded massive bodies. The long coherence time suggests the responsible bodies are concentrated near the edge of the ringlet. Long wake-like structures originate from two locations on the inner edge of the ringlet, revealing the locations of the two most massive embedded bodies in that region. As with the Voyager observations, the Cassini data sets showed no correlation between the width and the radius of the ringlet as would be expected for a self-gravitating configuration, except for a brief interval during late 2006, when the width-radius relation was similar to those seen in most other narrow eccentric ringlets in the Solar System.

  10. Characterization of Cassini GPHS Fueled-Clad Production Girth Welds

    Energy Technology Data Exchange (ETDEWEB)

    Franco-Ferreira, E.A.

    2000-03-23

    Fueled clads for radioisotope power systems are produced by encapsulating {sup 238}PuO{sub 2} in iridium alloy cups, which are joined at their equators by gas tungsten arc welding. Cracking problems at the girth weld tie-in area during production of the Galileo/Ulysses GPHS capsules led to the development of a first-generation ultrasonic test for girth weld inspection at the Savannah River Plant. A second-generation test and equipment with significantly improved sensitivity and accuracy were jointly developed by the Oak Ridge Y-12 Plant and Westinghouse Savannah River Company for use during the production of Cassini GPHS capsules by the Los Alamos National Laboratory. The test consisted of Lamb wave ultrasonic scanning of the entire girth weld from each end of the capsule combined with a time-of-flight evaluation to aid in characterizing nonrelevant indications. Tangential radiography was also used as a supplementary test for further evaluation of reflector geometry. Each of the 317 fueled GPHS capsules, which were girth welded for the Cassini Program, was subjected to a series of nondestructive tests that included visual, dimensional, helium leak rate, and ultrasonic testing. Thirty-three capsules were rejected prior to ultrasonic testing. Of the 44 capsules rejected by the standard ultrasonic test, 22 were upgraded to flight quality through supplementary testing for an overall process acceptance rate of 82.6%. No confirmed instances of weld cracking were found.

  11. Io Plasma Torus Ion Composition: Voyager, Galileo, Cassini

    Science.gov (United States)

    Bagenal, Fran; Nerney, Edward; Steffl, Andrew Joseph

    2016-10-01

    With JAXA's Hisaki spacecraft in orbit around Earth gathering information on the Io plasma torus and NASA's Juno mission measuring plasma conditions in the jovian magnetosphere, the time is ripe for a re-evaluation of earlier observations of the plasma torus to assess evidence for temporal variations. In particular, we are interested in exploring the ion composition of the torus and whether there is evidence of the ultimate source – the volcanic gases from Io – have deviated from SO2. We use the latest CHIANTI 8.0 atomic database to analyze UV spectra of the torus from Voyager, Galileo and Cassini as well as with the physical chemistry model of Delamere, Steffl and Bagenal (2005). We find that contrary to earlier analyses of Voyager data (e.g. Shemansky 1987; 1988) that produced a composition requiring a neutral source of O/S~4, we find an ion composition that is consistent with the Cassini UVIS data (Steffl et al. 2004) and a neutral O/S~2, consistent with SO2.

  12. OPUS: Now with Enhanced Geometric Metadata for Cassini Optical Remote Sensing Instruments

    Science.gov (United States)

    Gordon, M. K.; Showalter, M. R.; Ballard, L.; Heather, N.

    2015-06-01

    A recent upgrade of the PDS Rings Node’s search tool, OPUS, enables faster, more powerful search capabilities than before. Although OPUS is a Rings Node tool, it supports planet and satellite observations as well as ring observations.

  13. A close look at Saturn's rings with Cassini VIMS

    Science.gov (United States)

    Nicholson, P.D.; Hedman, M.M.; Clark, R.N.; Showalter, M.R.; Cruikshank, D.P.; Cuzzi, J.N.; Filacchione, G.; Capaccioni, F.; Cerroni, P.; Hansen, G.B.; Sicardy, B.; Drossart, P.; Brown, R.H.; Buratti, B.J.; Baines, K.H.; Coradini, A.

    2008-01-01

    Soon after the Cassini-Huygens spacecraft entered orbit about Saturn on 1 July 2004, its Visual and Infrared Mapping Spectrometer obtained two continuous spectral scans across the rings, covering the wavelength range 0.35-5.1 ??m, at a spatial resolution of 15-25 km. The first scan covers the outer C and inner B rings, while the second covers the Cassini Division and the entire A ring. Comparisons of the VIMS radial reflectance profile at 1.08 ??m with similar profiles at a wavelength of 0.45 ??m assembled from Voyager images show very little change in ring structure over the intervening 24 years, with the exception of a few features already known to be noncircular. A model for single-scattering by a classical, many-particle-thick slab of material with normal optical depths derived from the Voyager photopolarimeter stellar occultation is found to provide an excellent fit to the observed VIMS reflectance profiles for the C ring and Cassini Division, and an acceptable fit for the inner B ring. The A ring deviates significantly from such a model, consistent with previous suggestions that this region may be closer to a monolayer. An additional complication here is the azimuthally-variable average optical depth associated with "self-gravity wakes" in this region and the fact that much of the A ring may be a mixture of almost opaque wakes and relatively transparent interwake zones. Consistently with previous studies, we find that the near-infrared spectra of all main ring regions are dominated by water ice, with a typical regolith grain radius of 5-20 ??m, while the steep decrease in visual reflectance shortward of 0.6 ??m is suggestive of an organic contaminant, perhaps tholin-like. Although no materials other than H2O ice have been identified with any certainty in the VIMS spectra of the rings, significant radial variations are seen in the strength of the water-ice absorption bands. Across the boundary between the C and B rings, over a radial range of ???7000 km, the

  14. An Overview of the Bathymetry and Composition of Titan's Hydrocarbon Seas from the Cassini RADAR Altimeter

    Science.gov (United States)

    Mastrogiuseppe, M.; Hayes, A.; Lunine, J. I.; Poggiali, V.; Seu, R.; Hofgartner, J. D.; Lorenz, R. D.; Le Gall, A. A.

    2015-12-01

    The Cassini RADAR's altimetry mode has been successfully used for probing the depth and composition of Titan's hydrocarbons seas. In May 2013, during the spacecraft's 91stflyby of Titan (T91), the instrument demonstrates its capabilities as a radar sounder, presenting a unique opportunity to constrain direct measurements of the depth and composition of Titan's second largest sea, Ligeia Mare. Later, observations of Kraken Mare and Punga Mare were planned and executed in August 2014 (T104) and January 2015 (T108), respectively. While most of the seafloor was not detected at Kraken, suggesting the sea was either too deep or too absorptive in these areas to observe a return from the seafloor, shallow areas near Moray Sinus did return subsurface detections. At Punga Mare, a clear detection of the subsurface was observed with a maximum depth of 120 m along the interrogated track of the sea. We will present an analysis of all three altimetric observations of Titan's mare, as well a re-analysis of altimetry data acquired over southern Ontario Lacus. Depths measurements and liquid composition are obtained using a novel technique which makes use of radar simulations and Monte Carlo based inversions. Finally, we will show that the estimates obtained from the direct measurements described above can be used along with the RADAR's active (i.e. Synthetic Aperture Radar) and passive (Radiometry) modes to generate bathymetry maps of areas not observed by altimetry.

  15. Mapping and interpretation of Sinlap crater on Titan using Cassini VIMS and RADAR data

    Science.gov (United States)

    Le, Mouelic S.; Paillou, P.; Janssen, M.A.; Barnes, J.W.; Rodriguez, S.; Sotin, Christophe; Brown, R.H.; Baines, K.H.; Buratti, B.J.; Clark, R.N.; Crapeau, M.; Encrenaz, P.J.; Jaumann, R.; Geudtner, D.; Paganelli, F.; Soderblom, L.; Tobie, G.; Wall, S.

    2008-01-01

    Only a few impact craters have been unambiguously detected on Titan by the Cassini-Huygens mission. Among these, Sinlap is the only one that has been observed both by the RADAR and VIMS instruments. This paper describes observations at centimeter and infrared wavelengths which provide complementary information about the composition, topography, and surface roughness. Several units appear in VIMS false color composites of band ratios in the Sinlap area, suggesting compositional heterogeneities. A bright pixel possibly related to a central peak does not show significant spectral variations, indicating either that the impact site was vertically homogeneous, or that this area has been recovered by homogeneous deposits. Both VIMS ratio images and dielectric constant measurements suggest the presence of an area enriched in water ice around the main ejecta blanket. Since the Ku-band SAR may see subsurface structures at the meter scale, the difference between infrared and SAR observations can be explained by the presence of a thin layer transparent to the radar. An analogy with terrestrial craters in Libya supports this interpretation. Finally, a tentative model describes the geological history of this area prior, during, and after the impact. It involves mainly the creation of ballistic ejecta and an expanding plume of vapor triggered by the impact, followed by the redeposition of icy spherules recondensed from this vapor plume blown downwind. Subsequent evolution is then driven by erosional processes and aeolian deposition. Copyright 2008 by the American Geophysical Union.

  16. Nanodust detection between 1 and 5 AU by using Cassini wave measurements

    CERN Document Server

    Schippers, P; Lecacheux, A; Belheouane, S; Moncuquet, M; Kurth, W S; Mann, I; Mitchell, D G; André, N

    2015-01-01

    The solar system contains solids of all sizes, ranging from km-size bodies to nano-sized particles. Nanograins have been detected in situ in the Earth's atmosphere, near cometary and giant planet environments, and more recently in the solar wind at 1 AU. These latter nano grains are thought to be formed in the inner solar system dust cloud, mainly through collisional break-up of larger grains and are then picked-up and accelerated by the magnetized solar wind because of their large charge-to-mass ratio. In the present paper, we analyze the low frequency bursty noise identified in the Cassini radio and plasma wave data during the spacecraft cruise phase inside Jupiter's orbit. The magnitude, spectral shape and waveform of this broadband noise is consistent with the signature of nano particles impinging at nearby the solar wind speed on the spacecraft surface. Nanoparticles were observed whenever the radio instrument was turned on and able to detect them, at different heliocentric distances between Earth and Ju...

  17. Overview of the Cassini In-Situ Observations of Auroral Field-Aligned Currents During the 2013 Saturn Aurora Campaign

    Science.gov (United States)

    Bunce, E. J.; Badman, S. V.; Cowley, S. W.; Dougherty, M. K.; Gurnett, D. A.; Jinks, S.; Kurth, W. S.; Mitchell, D. G.; Nichols, J. D.; Provan, G.; Pryor, W. R.

    2013-12-01

    The Saturn Aurora Campaign 2013 is a coordinated effort to provide a clearer understanding of Saturn's auroral emissions at multiple wavelengths in the upper atmosphere, and their associated magnetospheric signatures and dynamics. Structures such as Corotating Interaction Regions (CIRs) are known to play a significant role in the modulation of Saturn's auroral emissions via abrupt changes in the dynamic pressure associated with forward shocks at the start of the CIR compression regions. Recent observations from the Cassini spacecraft at Saturn have also taught us that the 'magnetosphere oscillations' observed in magnetic field perturbations in the northern and southern hemispheres, which are associated with the SKR modulations in each hemisphere, also significantly modulate the magnetosphere and auroral emissions. Here we present an overview of the in situ magnetosphere measurements during the campaign, along with an overview of the solar wind conditions upstream of Saturn inferred from the Saturn Kilometric Radiation (SKR) emissions. We will discuss evidence of the high-latitude field-aligned currents and plasma boundaries (e.g. the open-closed field line (or related) boundary) from the magnetic field data, plasma signatures and/or auroral hiss observations (using the Cassini magnetometer-MAG, the Magnetospheric Imaging Instrument-MIMI, and the Radio Plasma Wave Science-RPWS instruments respectively). We will attempt to characterise the morphology and variability (e.g. co-latitude, intensity) of the current system(s) from both the knowledge of the northern or southern magnetosphere oscillation phase (according to the location of the spacecraft) and the inferred solar wind conditions. We will compare these results with available IR/UV auroral images from the campaign.

  18. Cratering on Titan: A Pre-Cassini Perspective

    Science.gov (United States)

    Lorenz, R. D.

    1997-01-01

    The NASA-ESA Cassini mission, comprising a formidably instrumented orbiter and parachute-borne probe to be launched this October, promises to reveal a crater population on Titan that has been heretofore hidden by atmospheric haze. This population on the largest remaining unexplored surface in the solar system will be invaluable in comparative planetological studies, since it introduces evidence of the atmospheric effects of cratering on an icy satellite. Here, I highlight some impact features we may hope to find and could devote some modeling effort toward. Titan in a Nutshell: Radius= 2575 km. Density= 1880 kg/cubic m consistent with rock-ice composition. Surface pressure = 1.5 bar. Surface gravity = 1.35 m/square s Atmosphere -94% N2 6% CH, Surface temperature = 94K Tropopause temperature = 70K at 40 km alt. Probable liquid hydrocarbon deposits exist on or near the surface.Titan in a Nutshell: Radius= 2575 km. Density= 1880 kg/cubic m consistent with rock-ice composition. Surface pressure = 1.5 bar. Surface gravity = 1.35 m/square s; Atmosphere about 94% N2 6% CH, Surface temperature = 94K Tropopause temperature = 70K at 40 km alt. Probable liquid hydrocarbon deposits exist on or near the surface. Titan is comparable to Callisto and Ganymede for strength/gravity, Mars/Earth/Venus for atmospheric interaction, and Hyperion, Rhea, and Iapetus for impactor distribution. The leading/trailing asymmetry of crater density from heliocentric impactors is expected to be about 5-6, in the absence of resurfacing. Any Saturnocentric impactor population is likely to alter this. In particular the impact disruption of Hyperion is noted; because of the 3:4 orbital resonance with Titan, fragments from the proto-Hyperion breakup would have rapidly accreted onto Titan. Titan's resurfacing history is of course unknown. The disruption of impactors into fragments that individually create small craters is expected to occur. A crude estimate suggests a maximum separation of about 2 km

  19. Cratering on Titan: A Pre-Cassini Perspective

    Science.gov (United States)

    Lorenz, R. D.

    1997-01-01

    The NASA-ESA Cassini mission, comprising a formidably instrumented orbiter and parachute-borne probe to be launched this October, promises to reveal a crater population on Titan that has been heretofore hidden by atmospheric haze. This population on the largest remaining unexplored surface in the solar system will be invaluable in comparative planetological studies, since it introduces evidence of the atmospheric effects of cratering on an icy satellite. Here, I highlight some impact features we may hope to find and could devote some modeling effort toward. Titan in a Nutshell: Radius= 2575 km. Density= 1880 kg/cubic m consistent with rock-ice composition. Surface pressure = 1.5 bar. Surface gravity = 1.35 m/square s Atmosphere -94% N2 6% CH, Surface temperature = 94K Tropopause temperature = 70K at 40 km alt. Probable liquid hydrocarbon deposits exist on or near the surface.Titan in a Nutshell: Radius= 2575 km. Density= 1880 kg/cubic m consistent with rock-ice composition. Surface pressure = 1.5 bar. Surface gravity = 1.35 m/square s; Atmosphere about 94% N2 6% CH, Surface temperature = 94K Tropopause temperature = 70K at 40 km alt. Probable liquid hydrocarbon deposits exist on or near the surface. Titan is comparable to Callisto and Ganymede for strength/gravity, Mars/Earth/Venus for atmospheric interaction, and Hyperion, Rhea, and Iapetus for impactor distribution. The leading/trailing asymmetry of crater density from heliocentric impactors is expected to be about 5-6, in the absence of resurfacing. Any Saturnocentric impactor population is likely to alter this. In particular the impact disruption of Hyperion is noted; because of the 3:4 orbital resonance with Titan, fragments from the proto-Hyperion breakup would have rapidly accreted onto Titan. Titan's resurfacing history is of course unknown. The disruption of impactors into fragments that individually create small craters is expected to occur. A crude estimate suggests a maximum separation of about 2 km

  20. A Look Toward the Surface: Radiative Transfer Modelling in Titan's Atmosphere Using Cassini/VIMS data

    Science.gov (United States)

    Cornet, Thomas; Rodriguez, Sebastien; Maltagliati, Luca; Appéré, Thomas; Sotin, Christophe; Le Mouélic, Stéphane; Rannou, Pascal; Solomonidou, Anezina; Hirtzig, Mathieu; Bézard, Bruno; Coustenis, Athena; Brown, Robert H.; Barnes, Jason W.; Baines, Kevin H.; Buratti, Bonnie J.; Clark, Roger N.; Nicholson, Phillip D.

    2017-04-01

    Saturn's moon Titan possesses a thick and opaque atmosphere, strongly absorbing and scattering in the infrared due to the presence of molecular gases (mostly N2 and CH4) and of a thick organic haze. Despite the presence of this atmosphere, the Cassini Visual and Infrared Mapping Spectrometer (VIMS) instrument is able to acquire images of Titan's surface in atmospheric transmission windows centered at 0.93, 1.08, 1.27, 1.59, 2.01, 2.7-2.8 and 5 μm in the infrared [1]. These imaging capabilities already contributed to reveal and investigate the geological diversity of Titan's surface [2,3,4], but the interpretation of the data in terms of surface composition is often limited due to the heavy processing required to disentangle atmospheric to surface contributions. In this context, we are developing an accurate and fast radiative transfer model and inversion scheme for Titan in order to massively invert the Titan VIMS dataset (125 flybys, tens of thousands of data cubes) and compute surface albedo maps to be used for geomorphological and compositional mapping studies using Cassini/VIMS data. The present model operates in plane-parallel approximation using the SHDOMPP solver [5], which mostly constrains our inversions to the equatorial regions of Titan, where the viewing geometry is suitable to the solver. Our inversion strategy in based on the calculation of reference Look-Up Tables (LUTs) [6] with the radiative transfer direct model [6-8], on which we perform a series of interpolations in order to retrieve the exact geometry of the data (incidence, emission and azimuth angles) and the associated haze opacity factor and surface albedo in order to match the input spectra. This methodology of inversion allows us to process VIMS cubes and mosaics of VIMS cubes in a couple of hours only (as compared to several days with classical approaches). We will apply this model to regional VIMS mosaics composed of several flybys, such as the T13-T17 mosaic. [1] Sotin C. et al. (2005

  1. Seasonal variations in Titan's stratosphere observed with Cassini/CIRS after the northern spring equinox

    Science.gov (United States)

    Vinatier, Sandrine; Bézard, Bruno; Teanby, Nicholas A.; Lebonnois, Sebastien; Achterberg, Richard; Gorius, Nicolas; Mamoutkine, Andrei; Flasar, F. Michael; CIRS Team

    2016-10-01

    Since 2004, Cassini has made more than 119 Titan flybys, observing its atmosphere with instruments including the Cassini Composite InfraRed Spectrometer (CIRS). We know from CIRS observations that the global dynamics drastically changed after the northern spring equinox that occurred in August 2009 ([1], [2], [3], [4]). The pole-to-pole middle atmosphere dynamics (above 100 km) experienced a global reversal in less than 2 years after the equinox [4], while the northern hemisphere was entering spring. This new pattern, with downwelling at the south pole, resulted in an enrichment of almost all molecules inside the southern polar vortex since 2011.We will present an analysis of CIRS limb observations up to 2016. We will show that many species (C2H2, HCN, HC3N, C6H6, C4H2, CH3CCH, C2H4) experienced their highest enrichments near the south pole near 500 km in March 2015, with abundances similar to in situ results from INMS at 1000 km [5], suggesting that the air inside the confined polar vortex (observed at latitudes higher than 80°S) was very efficiently transported downward from very high altitudes. In September 2015, an extension of the polar vortex towards lower latitudes (~65°S) was observed, while the molecular abundances decreased by a factor of 10 at 500 km. In the same region, unexpectedly cold stratospheric temperatures were observed below 300 km from May 2013 to the end of 2015, allowing us to detect for the first time the C6H6 ice signature at 680 cm-1. Simultaneously, after the disruption of the north polar vortex after the equinox, the enriched air that was previously confined at very high latitude gradually expended towards mid latitudes at altitudes higher than 300 km. At the beginning of 2016, a zone depleted in molecular gas and aerosol is observed in the entire northern hemisphere between 400 and 500 km, suggesting some complex unknown dynamical effect.References:[1] Teanby, N. et al., 2012, Nature, 491, pp. 733-735.[2] Achterberg et al., DPS 46

  2. Birotor dipole for Saturn's inner magnetic field from Cassini observations

    Science.gov (United States)

    Galopeau, Patrick

    2017-04-01

    The radio and plasma wave science (RPWS) experiment on board the Cassini spacecraft, orbiting around Saturn since July 2004, revealed the presence of two distinct and variable rotation periods in the Saturnian kilometric radiation (SKR). These two periods were attributed to the northern and southern hemispheres respectively. We suppose that the periodic time modulations present in the SKR are mainly due to the rotation of Saturn's inner magnetic field. The existence of a double period implies that the inner field is not only limited to a simple rotation dipole but displays more complex structures having the same time periodicities than the radio emission. In order to build a model of this complex magnetic field, it is absolutely necessary to know the accurate phases of rotation linked with the two periods. The radio observations from the RPWS experiment allow a continuous and accurate follow-up of these rotation phases, since the SKR emission is permanently observable and produced very close to the planetary surface. A continuous wavelet transform analysis of the intensity of the SKR signal received at 290 kHz between July 2004 and June 2012 was performed in order to calculate in the same time the different periodicities and phases. A dipole model was proposed for Saturn's inner magnetic field: this dipole presents the particularity to have North and South poles rotating around Saturn's axis at two different angular velocities; this dipole is tilted and not centered. 57 Cassini's revolutions, the periapsis of which is less than 5 Saturnian radii, have been selected for this study. For each of these chosen orbits, it is possible to fit with high precision the measurements of the MAG data experiment given by the magnetometers embarked on board Cassini. A nonrotating external magnetic field completes the model. This study suggests that Saturn's inner magnetic field is neither stationary nor fully axisymmetric. These results can be used as a boundary condition for

  3. Tidal Control of Jet Eruptions Observed by Cassini ISS

    Science.gov (United States)

    Hurford, T. A.; Helfenstein, P.; Spitale, J. N.

    2012-01-01

    Observations by Cassini's Imaging Science Subsystem (ISS) of Enceladus' south polar region at high phase angles has revealed jets of material venting into space. Observations by Cassini's Composite Infrared Spectrometer (CIRS) have also shown that the south polar region is anomalously warm with hotspots associated with geological features called the Tiger Stripes. The Tiger Stripes are large rifts near the south pole of Enceladus, which are typically about 130 km in length, 2 km wide, with a trough 500 m deep, and are l1anked on each side by 100m tall ridges. Preliminary triangulation of jets as viewed at different times and with different viewing geometries in Cassini ISS images taken between 2005 and 2007 have constrained the locations of eight major eruptions of material and found all of them associated with the south polar fractures unofficially the 'Tiger Stripes', and found four of them coincident with the hotspots reported in 2006 by CIRS. While published ISS observations of jet activity suggest that individual eruption sites stay active on the timescale of years, any shorter temporal variability (on timescales of an orbital period, or 1.3 Earth days, for example) is more difficult to establish because of the spotty temporal coverage and the difficulty of visually isolating one jet from the forest of many seen in a typical image. Consequently, it is not known whether individual jets are continuously active, randomly active, or if they erupt on a predictable, periodic schedule. One mechanism that may control the timing of eruptions is diurnal tidal stress, which oscillates between compression/tension as well as right and left lateral shear at any given location throughout Enceladus' orbit and may allow the cracks to open and close regularly. We examine the stresses on the Tiger Stripe regions to see how well diurnal tidal stress caused by Enceladus' orbital eccentricity may possibly correlate with and thus control the observed eruptions. We then identify

  4. Cassini-plasma interactions in the Enceladus torus

    Science.gov (United States)

    Yaroshenko, V. V.; Miloch, W. J.; Morfill, G. E.

    2012-04-01

    This study reports the results of the first simulations of spacecraft-plasma interactions within the proposed Enceladus torus, a radially narrow toroidal region surrounding Saturn that contains a high density of water-group neutrals. Charge exchange collisions scatter these neutrals and replace a fraction of the co-rotating ions with a new and slower-moving ion population. The newly-created ions are moving near the local Keplerian speed, slower than the co-rotation speed, and are ''picked-up'' by Saturn's magnetic field. These water-group ions are detected throughout the Enceladus torus including regions far from Enceladus [1,2]. Three-dimensional particle-in-cell self-consistent code is applied to find the potential and plasma distributions around the spherical model of Cassini in a complicated plasma environment of the Enceladus torus. The modeling includes two types of water group ions (co-rotating, and non-thermalized pick-up ions), plasma flows, photoemission due to solar UV radiation, and flyby geometry. As input data the parameters derived from the Cassini plasma spectrometer measurements obtained in 2005 on Oct. 11, and 29, Nov. 27, and Dec. 24 [1] are employed. The numerical simulations show that the pick-up ions significantly modify the spatial structure of the plasma perturbations, arising in the vicinity of the orbiter in comparison to that obtained for only co-rotating ions [3]. The plasma species produce a specific strongly inhomogeneous configuration with a self-consistent charge separation between the different plasma components in the electric field of the orbiter. The highly energetic co-rotating water group ions are mainly responsible for the configuration of the plasma wake. The region extending up to a few electron Debye lengths downstream of the spacecraft reveals negative potentials that are a significant fraction of the thermal electron energy. Arising wake electric fields capture the cold, pick-up ions and lead to a strong enhancement of

  5. Constraints on Titan's rotation from Cassini mission radar data

    Science.gov (United States)

    Bills, Bruce; Stiles, Bryan W.; Hayes, Alexander

    2015-05-01

    We present results of a new analysis of the rotational kinematics of Titan, as constrained by Cassini radar data, extending over the entire currently available set of flyby encounters. Our analysis provides a good constraint on the current orientation of the spin pole, but does not have sufficient accuracy and duration to clearly see the expected spin pole precession. In contrast, we do clearly see temporal variations in the spin rate, which are driven by gravitational torques which attempt to keep the prime meridian oriented toward Saturn.Titan is a synchronous rotator. At lowest order, that means that the rotational and orbital motions are synchronized. At the level of accuracy required to fit the Cassini radar data, we can see that synchronous rotation and uniform rotation are not quite the same thing. Our best fitting model has a fixed pole, and a rotation rate which varies with time, so as to keep Titan's prime meridian oriented towards Saturn, as the orbit varies.A gravitational torque on the tri-axial figure of Titan attempts to keep the axis of least inertia oriented toward Saturn. The main effect is to synchronize the orbit and rotation periods, as seen in inertial space. The response of the rotation angle, to periodic changes in orbital mean longitude, is modeled as a damped, forced harmonic oscillator. This acts as a low-pass filter. The rotation angle accurately tracks orbital variations at periods longer than the free libration period, but is unable to follow higher frequency variations.The mean longitude of Titan's orbit varies on a wide range of time scales. The largest variations are at Saturn's orbital period (29.46 years), and are due to solar torques. There are also variations at periods of 640 and 5800 days, due to resonant interaction with Hyperion.For a rigid body, with moments of inertia estimated from observed gravity, the free libration period for Titan would be 850 days. The best fit to the radar data is obtained with a libration period of

  6. Maneuver Performance Assessment of the Cassini Spacecraft Through Execution-Error Modeling and Analysis

    Science.gov (United States)

    Wagner, Sean

    2014-01-01

    The Cassini spacecraft has executed nearly 300 maneuvers since 1997, providing ample data for execution-error model updates. With maneuvers through 2017, opportunities remain to improve on the models and remove biases identified in maneuver executions. This manuscript focuses on how execution-error models can be used to judge maneuver performance, while providing a means for detecting performance degradation. Additionally, this paper describes Cassini's execution-error model updates in August 2012. An assessment of Cassini's maneuver performance through OTM-368 on January 5, 2014 is also presented.

  7. Maneuver Performance Assessment of the Cassini Spacecraft Through Execution-Error Modeling and Analysis

    Science.gov (United States)

    Wagner, Sean

    2014-01-01

    The Cassini spacecraft has executed nearly 300 maneuvers since 1997, providing ample data for execution-error model updates. With maneuvers through 2017, opportunities remain to improve on the models and remove biases identified in maneuver executions. This manuscript focuses on how execution-error models can be used to judge maneuver performance, while providing a means for detecting performance degradation. Additionally, this paper describes Cassini's execution-error model updates in August 2012. An assessment of Cassini's maneuver performance through OTM-368 on January 5, 2014 is also presented.

  8. Cassini Attitude Control Fault Protection Design: Launch to End of Prime Mission Performance

    Science.gov (United States)

    Meakin, Peter C.

    2008-01-01

    The Cassini Attitude and Articulation Control Subsystem (AACS) Fault Protection (FP) has been successfully supporting operations for over 10 years from launch through the end of the prime mission. Cassini's AACS FP is complex, containing hundreds of error monitors and thousands of tunable parameters. Since launch there have been environmental, hardware, personnel and mission event driven changes which have required AACS FP to adapt and be robust to a variety of scenarios. This paper will discuss the process of monitoring, maintaining and updating the AACS FP during Cassini's lengthy prime mission as well as provide some insight into lessons learned during tour operations.

  9. Cassini Attitude Control Fault Protection Design: Launch to End of Prime Mission Performance

    Science.gov (United States)

    Meakin, Peter C.

    2008-01-01

    The Cassini Attitude and Articulation Control Subsystem (AACS) Fault Protection (FP) has been successfully supporting operations for over 10 years from launch through the end of the prime mission. Cassini's AACS FP is complex, containing hundreds of error monitors and thousands of tunable parameters. Since launch there have been environmental, hardware, personnel and mission event driven changes which have required AACS FP to adapt and be robust to a variety of scenarios. This paper will discuss the process of monitoring, maintaining and updating the AACS FP during Cassini's lengthy prime mission as well as provide some insight into lessons learned during tour operations.

  10. ORGANIZAÇÃO E DESEMPENHO: AVALIAÇÃO DA CENTRALIZAÇÃO DA PATOLOGIA DO INCA-BRASIL

    Directory of Open Access Journals (Sweden)

    Marcelino José Jorge

    2014-10-01

    Full Text Available Literature widely assigns positive effects on entrepreneurial orientation and firm performance to decentralization of organizational structure; at the same time, there is evidence of positive effects of centralization of complex procedures in large hospitals on the results of cancer treatment. This study intends to evaluate the effects of centralization of pathology laboratories at the National Cancer Institute (INCA of Brazil in 2002 on the performance of diagnostic activity and cancer control. A non-parametric efficiency frontier for the pathology labs is calculated for the period 1997-2007 by means of Data Envelopment Analysis (DEA. Findings show that centralization reversed the decline of technical efficiency in the laboratories along the period 1997-2001. The main conclusion is that the DEA model brings a contribution to knowledge about change in organizational structure in public health organizations, as well as a managerial contribution on the effectiveness of centralization to improve the support of pathology labs to INCA hospitals.

  11. An Overview of Observations by the Cassini Radio and Plasma Wave Investigation at Earth

    Science.gov (United States)

    Kurth, W. S.; Hospodarsky, G. B.; Gurnett, D. A.; Kaiser, M. L.; Wahlund, J.-E.; Roux, A.; Canu, P.; Zarka, P.; Tokarev, Y.

    2001-01-01

    On August 18, 1999, the Cassini spacecraft flew by Earth at an altitude of 1186 km on its way to Saturn. Although the flyby was performed exclusively to provide the spacecraft with sufficient velocity to get to Saturn, the radio and plasma wave science (RPWS) instrument, along with several others, was operated to gain valuable calibration data and to validate the operation of a number of capabilities. In addition, an opportunity to study the terrestrial radio and plasma wave environment with a highly capable instrument on a swift fly-through of the magnetosphere was afforded by the encounter. This paper provides an overview of the RPWS observations, at Earth, including the identification of a number of magnetospheric plasma wave modes, an accurate measurement of the plasma density over a significant portion of the trajectory using the natural wave spectrum in addition to a relaxation sounder and Langmuir probe, the detection of natural and human-produced radio emissions, and the validation of the capability to measure the wave normal angle and Poynting flux of whistler-mode chorus emissions. The results include the observation of a double-banded structure at closest' approach including a band of Cerenkov emission bounded by electron plasma and upper hybrid frequencies and an electron cyclotron harmonic band just above the second harmonic of the electron cyclotron frequency. In the near-Earth plasma sheet, evidence for electron phase space holes is observed, similar to those first reported by Geotail in the magnetotail. The wave normal analysis confirms the Polar result that chorus is generated very close to the magnetic equator and propagates to higher latitudes. The integrated power flux of auroral kilometric radiation is also used to identify a series of substorms observed during the outbound passage through the magnetotail.

  12. Constrains on the nature of Titan's surface from Cassini/VIMS and RADAR

    Science.gov (United States)

    Solomonidou, Anezina; Coustenis, Athena; Lopes, Rosaly; Rodriguez, Sebastien; Drossart, Pierre; Schmitt, Bernard; Philippe, Sylvain; Malaska, Michael; Janssen, Michael; Maltagliati, Luca; Lawrence, Kenneth; Jaumann, Ralf; Sohl, Frank; Stephan, Katrin; Brown, Robert; Bratsolis, Emannuel; Matsoukas, Christos

    2016-04-01

    Cassini remote-sensing instruments for more than 10 years now and in situ by the Huygens instruments back in 2005. For the surface, the presence of diverse terrains in terms of morphology and composition suggest both exogenic and endogenic processes to be at play. In this study, we investigate the surface and atmospheric contributions from the Visual and Infrared Mapping Spectrometer (VIMS) spectro-imaging data by use of a radiative transfer code in the near-IR range and the RADAR/SAR data for the distinction of geomorphological units. We focus here on those units identified in Lopes et al. (2010, 2015) [1; 2] and Malaska et al. (2015) [3]: mountains, plains, labyrinths, dune fields, and the areas previously suggested to have experienced change such as the possible cryovolcanic and evaporite features (Barnes et al. 2013; Solomonidou et al. 2014; 2015) [4; 5; 6]. With the use of a recently updated radiative transfer code, we evaluate the atmospheric contribution and extract the pure surface albedo information for each region of interest. The extracted albedo shapes and values are then tested against spectra of constituents that are considered to be the best Titan candidate materials, including a very recent library of Titan ice spectra [7]. We find that many of the units show compositional variations while units of significant geomorphological differences seem to consist of very similar materials, which help us provide implications on their endogenic or exogenic origin. Preliminary results on the chemical composition of the regions that have shown temporal changes are also presented. References: [1] Lopes, R.M.C., et al.: Icarus, 205, 540-558, 2010; [2] Lopes, R.M.C., et al.: Icarus, in press; [3] Malaska, M., et al. : Icarus, submitted; [4] Barnes, J., et al.: Planetary Science, 2:1, 2013; [5] Solomonidou, A., et al.: JGR, 119, 1729-1747, 2014; [6] Solomonidou, A., et al.: Icarus, in press; [7] Schmitt, B., et al.: GhoSST datacase (ghosst.osug.fr).

  13. Genealogía de un origen: Túbal, el falsario y la Atlántida en la Historia de los Incas de Pedro Sarmiento de Gamboa

    Directory of Open Access Journals (Sweden)

    González Díaz, Soledad

    2012-08-01

    Full Text Available The present article proposes a political reading of two texts that are connected to each other: the History of the Incas by Pedro Sarmiento de Gamboa and the Antiquitatum Variarum by Annio de Viterbo, a collection of spurious texts from the end of the 15th century. Doing a synthesis between the Antiquitatum and the platonic myth of Atlantis, Sarmiento argued that the Indians were descendants of Túbal lineage, the grandson of Noah and founder of the Hispanic monarchy which had come to the Indies after the Universal Flood. It is proposed that the History of the Incas as well as the Antiquitatum were part of an official current of imperial representation of the past promoted by the Catholic Kings, that was projected to Spanish and Indies chronicles during the 16th century.El presente artículo propone una lectura política de dos libros vinculados entre sí: la Historia de los Incas de Pedro Sarmiento de Gamboa y la Antiquitatum Variarum de Annio de Viterbo, una colección de textos espurios de fines del siglo XV. Haciendo una síntesis entre la Antiquitatum y el mito platónico de la Atlántida, Sarmiento argumentó que los indios descendían de la estirpe de Túbal, el nieto de Noé y fundador de la monarquía hispánica, que había llegado a las Indias después del Diluvio Universal. Se propone que tanto la Historia de los Incas como la Antiquitatum formaron parte de una corriente oficial de representación del pasado de corte imperial promovida por los Reyes Católicos, que se proyectó a las crónicas hispanas y a las de Indias en el transcurso del siglo XVI.

  14. Trends in food intake in French children from 1999 to 2007: results from the INCA (étude Individuelle Nationale des Consommations Alimentaires) dietary surveys.

    Science.gov (United States)

    Lioret, Sandrine; Dubuisson, Carine; Dufour, Ariane; Touvier, Mathilde; Calamassi-Tran, Gloria; Maire, Bernard; Volatier, Jean-Luc; Lafay, Lionel

    2010-02-01

    The objectives of the present study were to assess the intake of different food groups in French children aged 3-17 years (n 1455), and to analyse trends since a dietary survey undertaken 8 years ago. Dietary intake was evaluated using data from the 2006-7 cross-sectional INCA2 national dietary survey (étude Individuelle Nationale sur les Consommations Alimentaires), based on a 7 d food record. Dietary intake (percentage of subjects consuming the food group and amount eaten) was assessed for thirty-nine food categories. We observed variations in food consumption by age, sex, North-South regional gradient, seasonal period and educational level of the responding parent. Trends in dietary intake between 1999 and 2007 were determined by comparing the INCA1 (n 1126) and the INCA2 surveys. Both surveys had been carried out using the same methodology. The findings showed a decrease in energy intake in children aged 3-14 years, due to a reduction in the consumption of foods of animal origin and sweetened products. In adolescents aged 15-17 years, energy intake remained rather stable; during this 8-year period, the consumption of meat decreased, whereas the consumption of savoury snacks such as sandwiches and hamburgers significantly increased. These trends occurred during a time of growing concern about overweight and the associated co-morbidities in France. A number of public health measures were implemented over this period to improve dietary habits and physical activity patterns in children and adults. The periodic monitoring of dietary patterns through the INCA surveys is an essential part of the surveillance network in France.

  15. Exploration of Kronian Magnetosheath Turbulence Using Cassini Data.

    Science.gov (United States)

    Hadid, L.; Sahraoui, F.; Retino, A.; Kiyani, K.; Modolo, R.; Canu, P.; Masters, A.; Dougherty, M. K.

    2014-04-01

    The power density spectra and the magnetic compressibility in Saturn's magnetosheath are investigated using in-situ measurements of the fields and particles from Cassini spacecraft mission. Two major results are found. 1) The absence of the f-5/3 Kolmogorov-like inertial range: the averaged magnetic power spectral densities indicate that the spectra jump from a 1/f scaling at the large scales (typical for solar wind spectra, Leamon et al. 1999) directly into the ion scales with a slope of - 2.5 ,without forming any 5/3 inertial range. Furthermore 2) computing the magnetic compressibility we show the dominance of the compressible magnetosonic modes at the kinetic scales compared with Kinetic Alfven Waves (KAW) reported in the solar wind (Sahraoui et al 2009 )

  16. Cassini Main Engine Assembly Cover Flight Management and Performance

    Science.gov (United States)

    Somawardhana, Ruwan P.; Millard, Jerry M.

    2010-01-01

    The Cassini spacecraft has performed its four year Prime Mission at Saturn and is currently in orbit at Saturn performing a two year extended mission. 12Its main engine nozzles are susceptible to impact damage from micrometeoroids and on-orbit dust. The spacecraft has an articulating device known as the Main Engine Assembly (MEA) cover which can close and shield the main engines from these threats. The cover opens to allow for main engine burns that are necessary to maintain the trajectory. Periodically updated analyses of potential on-orbit dust hazard threats have resulted in the need to continue to use the MEA cover beyond its intended use and beyond its design life. This paper provides a detailed Systems-level overview of the flight management of the MEA cover device and its flight performance to date.

  17. The Gravity Field of Enceladus from the three Cassini Flybys

    Science.gov (United States)

    Iess, L.; Parisi, M.; Ducci, M.; Jacobson, R. A.; Armstrong, J. W.; Asmar, S. W.; Lunine, J. I.; Stevenson, D. J.; Tortora, P.

    2013-12-01

    The Cassini spacecraft carried out gravity measurements of the small Saturnian moon Enceladus during three close flybys on April 28, 2010, November 30, 2010 and May 2, 2012 (designated E9, E12 and E19), at the low altitudes of 100, 48 and 70 km to maximize the accelerations exerted by the moon on the spacecraft. The goals of these observations were the determination of the gravitational quadrupole and the search for a North-South asymmetry in the gravity field, controlled primarily by the spherical harmonic coefficient C30. The estimation of Enceladus' gravity field is especially complex because of the small surface gravity (0.11 m/s2), the short duration of the gravitational interaction and the small number of available flybys. In addition to the gravitational accelerations, the spacecraft was also subject to small but non-negligible drag when it flew through the plume emitted from the south pole of the satellite. This effect occurred during the two south polar flybys E9 and E19. The inclusion of these non-gravitational accelerations proved to be crucial to attain a stable solution for the gravity field. Our estimation relied entirely on precise range rate measurements enabled by a coherent, two-way, microwave link at X-band (7.2-8.4 GHz). Measurement accuracies of 10 micron/s at 60 s integration times were attained under favorable conditions, thanks also to an advanced tropospheric calibration system. The data were fitted using the MONTE orbit determination code, recently developed by JPL for deep space navigation. In addition to the satellite degree 2 gravity field and C30, the solution included the state vector of the spacecraft (one for each flyby) and corrections to the mass and the initial orbital elements of Enceladus. The effect of the drag in E9 and E19 was modeled either as an unknown, impulsive, vectorial delta-V at closest approach, or by using density profiles from models of the plume and solving for the aerodynamic coefficient of the spacecraft. Both

  18. Cassini observations of ion cyclotron waves and ions anisotropy

    Science.gov (United States)

    Crary, F. J.; Dols, V. J.; Cassidy, T. A.; Tokar, R. L.

    2013-12-01

    In Saturn's equatorial, inner magnetosphere, the production of fresh ions in a pick-up distribution generates ion cyclotron waves. These waves are a sensitive indicator of fresh plasma production, but the quantitative relation between wave properties and ionization rates is nontrivial. We present a combined analysis of Cassini MAG and CAPS data, from a variety of equatorial orbits between 2005 and 2012. Using the MAG data, we determine the amplitude and peak frequency of ion cyclotron waves. From the CAPS data we extract the parallel and perpendicular velocity distribution of water group ions. We compare these results with hybrid simulations of the ion cyclotron instability and relate the observed wave amplitudes and ion velocity distributions to the production rate of pickup ions. The resulting relation between wave and plasma properties will allow us to infer ion production rates even at times when no direct ion measurements are available.

  19. Cassini discovers a kinematic spiral ring around Saturn.

    Science.gov (United States)

    Charnoz, S; Porco, C C; Déau, E; Brahic, A; Spitale, J N; Bacques, G; Baillie, K

    2005-11-25

    Since the time of the Voyager flybys of Saturn in 1980-1981, Saturn's eccentric F ring has been known to be accompanied on either side by faint strands of material. New Cassini observations show that these strands, initially interpreted as concentric ring segments, are in fact connected and form a single one-arm trailing spiral winding at least three times around Saturn. The spiral rotates around Saturn with the orbital motion of its constituent particles. This structure is likely the result of differential orbital motion stretching an initial cloud of particles scattered from the dense core of the F ring. Different scenarios of formation, implying ringlet-satellite interactions, are explored. A recently discovered moon candidate, S/2004 S6, is on an orbit that crosses the F-ring core at the intersection of the spiral with the ring, which suggests a dynamical connection between S/2004 S6 and the spiral.

  20. Meteorology of Jupiter's Equatorial Hot Spots and Plumes from Cassini

    CERN Document Server

    Choi, David S; Vasavada, Ashwin R; Simon-Miller, Amy A

    2013-01-01

    We present an updated analysis of Jupiter's equatorial meteorology from Cassini observations. For two months preceding the spacecraft's closest approach, the Imaging Science Subsystem (ISS) onboard regularly imaged the atmosphere. We created time-lapse movies from this period in order to analyze the dynamics of equatorial hot spots and their interactions with adjacent latitudes. Hot spots are quasi-stable, rectangular dark areas on visible-wavelength images, with defined eastern edges that sharply contrast with surrounding clouds, but diffuse western edges serving as nebulous boundaries with adjacent equatorial plumes. Hot spots exhibit significant variations in size and shape over timescales of days and weeks. Some of these changes correspond with passing vortex systems from adjacent latitudes interacting with hot spots. Strong anticyclonic gyres present to the south and southeast of the dark areas appear to circulate into hot spots. Impressive, bright white plumes occupy spaces in between hot spots. Compact...

  1. Instrumentation Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Provides instrumentation support for flight tests of prototype weapons systems using a vast array of airborne sensors, transducers, signal conditioning and encoding...

  2. Enceladus Plume Structure and Time Variability: Comparison of Cassini Observations.

    Science.gov (United States)

    Teolis, Ben D; Perry, Mark E; Hansen, Candice J; Waite, J Hunter; Porco, Carolyn C; Spencer, John R; Howett, Carly J A

    2017-09-05

    During three low-altitude (99, 66, 66 km) flybys through the Enceladus' plume in 2010 and 2011, Cassini's ion neutral mass spectrometer (INMS) made its first high spatial resolution measurements of the plume's gas density and distribution, detecting in situ the individual gas jets within the broad plume. Since those flybys, more detailed Imaging Science Subsystem (ISS) imaging observations of the plume's icy component have been reported, which constrain the locations and orientations of the numerous gas/grain jets. In the present study, we used these ISS imaging results, together with ultraviolet imaging spectrograph stellar and solar occultation measurements and modeling of the three-dimensional structure of the vapor cloud, to constrain the magnitudes, velocities, and time variability of the plume gas sources from the INMS data. Our results confirm a mixture of both low and high Mach gas emission from Enceladus' surface tiger stripes, with gas accelerated as fast as Mach 10 before escaping the surface. The vapor source fluxes and jet intensities/densities vary dramatically and stochastically, up to a factor 10, both spatially along the tiger stripes, and over time between flyby observations. This complex spatial variability and dynamics may result from time-variable tidal stress fields interacting with subsurface fissure geometry and tortuosity beyond detectability, including changing gas pathways to the surface, and fluid flow and boiling in response evolving lithostatic stress conditions. The total plume gas source has 30% uncertainty depending on the contributions assumed for adiabatic and nonadiabatic gas expansion/acceleration to the high Mach emission. The overall vapor plume source rate exhibits stochastic time variability up to a factor ∼5 between observations, reflecting that found in the individual gas sources/jets. Key Words: Cassini at saturn-Geysers-Enceladus-Gas dynamics-Icy satellites. Astrobiology 17, xxx-xxx.

  3. Saturn's equatorial jet structure from Cassini/ISS

    Science.gov (United States)

    García-Melendo, Enrique; Legarreta, Jon; Sánchez-Lavega, Agustín.; Pérez-Hoyos, Santiago; Hueso, Ricardo

    2010-05-01

    Detailed wind observations of the equatorial regions of the gaseous giant planets, Jupiter and Saturn, are crucial for understanding the basic problem of the global circulation and obtaining new detailed information on atmospheric phenomena. In this work we present high resolution data of Saturn's equatorial region wind profile from Cassini/ISS images. To retrieve wind measurements we applied an automatic cross correlator to image pairs taken by Cassini/ISS with the MT1, MT2, MT3 filters centred at the respective three methane absorbing bands of 619nm, 727nm, and 889nm, and with the adjacent continuum CB1, CB2, and CB3 filters. We obtained a complete high resolution coverage of Saturn's wind profile in the equatorial region. The equatorial jet displays an overall symmetric structure similar to that shown the by same region in Jupiter. This result suggests that, in accordance to some of the latest compressible atmosphere computer models, probably global winds in gaseous giants are deeply rooted in the molecular hydrogen layer. Wind profiles in the methane absorbing bands show the effect of strong vertical shear, ~40m/s per scale height, confirming previous results and an important decay in the wind intensity since the Voyager era (~100 m/s in the continuum and ~200 m/s in the methane absorbing band). We also report the discovery of a new feature, a very strong and narrow jet on the equator, about only 5 degrees wide, that despite the vertical shear maintains its intensity (~420 m/s) in both, the continuum and methane absorbing band filters. Acknowledgements: Work supported by the Spanish MICIIN AYA2009-10701 with FEDER and Grupos Gobierno Vasco IT-464-07.

  4. Tidally modulated eruptions on Enceladus: Cassini ISS observations and models

    Energy Technology Data Exchange (ETDEWEB)

    Nimmo, Francis [Department of Earth and Planetary Sciences, University of California, Santa Cruz, CA 95064 (United States); Porco, Carolyn; Mitchell, Colin, E-mail: carolyn@ciclops.org [CICLOPS, Space Science Institute, Boulder, CO 80304 (United States)

    2014-09-01

    We use images acquired by the Cassini Imaging Science Subsystem (ISS) to investigate the temporal variation of the brightness and height of the south polar plume of Enceladus. The plume's brightness peaks around the moon's apoapse, but with no systematic variation in scale height with either plume brightness or Enceladus' orbital position. We compare our results, both alone and supplemented with Cassini near-infrared observations, with predictions obtained from models in which tidal stresses are the principal control of the eruptive behavior. There are three main ways of explaining the observations: (1) the activity is controlled by right-lateral strike slip motion; (2) the activity is driven by eccentricity tides with an apparent time delay of about 5 hr; (3) the activity is driven by eccentricity tides plus a 1:1 physical libration with an amplitude of about 0.°8 (3.5 km). The second hypothesis might imply either a delayed eruptive response, or a dissipative, viscoelastic interior. The third hypothesis requires a libration amplitude an order of magnitude larger than predicted for a solid Enceladus. While we cannot currently exclude any of these hypotheses, the third, which is plausible for an Enceladus with a subsurface ocean, is testable by using repeat imaging of the moon's surface. A dissipative interior suggests that a regional background heat source should be detectable. The lack of a systematic variation in plume scale height, despite the large variations in plume brightness, is plausibly the result of supersonic flow; the details of the eruption process are yet to be understood.

  5. Analyzing Bleriot's propeller gaps in Cassini NAC images

    Science.gov (United States)

    Hoffmann, Holger; Chen, Cheng; Seiß, Martin; Albers, Nicole; Spahn, Frank; Nic

    2016-10-01

    Among the great discoveries of the Cassini mission are the propeller-shaped structures created by small moonlets embedded in Saturn's dense rings. These moonlets are not massive enough to counteract the viscous ring diffusion to open and maintain circumferential gaps, distinguishing them from ring-moons like Pan and Daphnis.Although one of the defining features of propeller structures, well-formed partial gaps have been resolved by the Imaging Science Subsystem Narrow Angle Camera onboard the Cassini spacecraft only for the largest known propeller named Bleriot. We analyze images of the sunlit side of Saturn's outer A ring showing the propeller Bleriot with clearly visible gaps. By fitting a Gaussian to radial brightness profiles at different azimuthal locations, we obtain the evolution of gap minimum and gap width downstream of the moonlet.We report two findings:1) Numerical simulations indicate that the radial separation of the partial propeller gaps is expected to be 4 Hill radii (Spahn and Sremcevic, 2000, A&A). We infer Bleriot's Hill radius to be a few hundred meters, consistent with values given by Sremcevic et al. (2014, DPS) and Hoffmann et al. (2015, Icarus).2) In order to estimate the ring viscosity in the region of Saturn's outer A ring, where Bleriot orbits, we fit several model functions (one example being the analytic solution derived by Sremcevic, Spahn and Duschl, 2002, MNRAS) describing the azimuthal evolution of the surface density in the propeller gap region to the data obtained from the image analysis. We find viscosity values consistent with the parameterization of ring viscosity by Daisaka et al. (2001, Icarus), but significantly lower than the upper limit given by Esposito et al. (1983, Icarus)

  6. ARAC's operational support of the Cassini Launch

    Energy Technology Data Exchange (ETDEWEB)

    Baskett, R L; Pace, J C

    1998-10-01

    The Atmospheric Release Advisory Capability (ARAC) program at the Lawrence Livermore National Laboratory (LLNL) was the U.S. Department of Energy atmospheric modeling resource used for the contingency of potential radiological releases during the launch of the Cassini mission. The ARAC Center at LLNL forecasted detailed weather conditions and delivered consequence assessments for potential accident scenarios to NASA before and during launch operations. A key aspect of ARAC's support was to acquire a variety of meteorological data for use in both forecast and real-time model calculations. ARAC acquired electronically two types of real-time observed meteorological data: 1) the full set of on-site towers and profilers via the Cape Canaveral Air Station (CCAS) Meteorological Interactive Data Display System (MIDDS), and 2) routine regional airport observations (delivered to the ARAC Center from the Air Force Weather Agency). We also used two forecasted data sources: 1) the U.S. Air Force 45th Weather Squadron at CCAS forecasted soundings for launch time, and 2) the Navy Operational Regional Atmospheric Prediction System (NORAPS) prognostic model which ARAC ran over the Cape. The NORAPS runs produced detailed 24-hr forecasts of 3-D wind fields. ARAC used default radiological accident source terms involving the potential destruction of Cassini's Radioisotope Thermoelectric Generators (RTGs) during 3 phases: 1) before the launch, 2) during the first S set after ignition, and 3) from 5 to 143 set after ignition. ARAC successfully developed and delivered dose and deposition plots at 24 hours, 3 hours, and 30 minutes before each of the lau

  7. ARAC's radiological support of the Cassini Launch

    Energy Technology Data Exchange (ETDEWEB)

    Baskett, R L; Pace, J C

    1998-10-01

    The Atmospheric Release Advisory Capability (ARAC) program at the Lawrence Livermore National Laboratory (LLNL) was the U.S. Department of Energy atmospheric modeling resource used for the contingency of potential radiological releases during the launch of the Cassini mission. Having the ARAC system up and running was one of the launch criteria during the countdown. The ARAC Center at LLNL forecasted detailed weather conditions and delivered consequence assessments for potential accident scenarios to NASA before and during launch operations. A key aspect of ARAC's support was to acquire a variety of meteorological data for use in both forecast and real-time model calculations. ARAC acquired electronically two types of real-time observed meteorological data: 1) the set of on-site tower and profiler data via the Cape Canaveral Air Station (CCAS) Meteorological Interactive Data Display System (MIDDS), and 2) routine regional airport observations delivered to the ARAC Center from the Air Force Weather Agency. We also used two forecasted data sources: 1) the U.S. Air Force 45th Weather Squadron at CCAS forecasted soundings for launch time, and 2) the Navy Operational Regional Atmospheric Prediction System (NORAPS) prognostic model which ARAC ran over the Cape. The NORAPS runs produced detailed 24-hr forecasts of 3-D wind fields. ARAC used default radiological accident source terms involving the potential destruction of Cassini's Radioisotope Thermoelectric Generators (RTGs) during 3 phases: 1) before the launch, 2) during the first 5 sec after ignition, and 3) from 5 to 143 sec after ignition. ARAC successfully developed and delivered dose and deposition plots at 24 hours, 3 hours, and 30 minutes before each of the launch windows.

  8. Rhea gravity field and interior modeling from Cassini data analysis

    Science.gov (United States)

    Tortora, Paolo; Zannoni, Marco; Hemingway, Doug; Nimmo, Francis; Jacobson, Robert A.; Iess, Luciano; Parisi, Marzia

    2016-01-01

    During its tour of the Saturn system, Cassini performed two close flybys of Rhea dedicated to gravity investigations, the first in November 2005 and the second in March 2013. This paper presents an estimation of Rhea's fully unconstrained quadrupole gravity field obtained from a joint multi-arc analysis of the two Cassini flybys. Our best estimates of the main gravity quadrupole unnormalized coefficients are J2 × 106 = 946.0 ± 13.9, C22 × 106 = 242.1 ± 4.0 (uncertainties are 1-σ). Their resulting ratio is J2/C22 = 3.91 ± 0.10, statistically not compatible (at a 5-σ level) with the theoretical value of 10/3, predicted for a hydrostatic satellite in slow, synchronous rotation around a planet. Therefore, it is not possible to infer the moment of inertia factor directly using the Radau-Darwin approximation. The observed excess J2 (gravity oblateness) was investigated using a combined analysis of gravity and topography, under different plausible geophysical assumptions. The observed gravity is consistent with that generated by the observed shape for an undifferentiated (uniform density) body. However, because the surface is more likely to be water ice, a two-layer model may be a better approximation. In this case, and assuming a mantle density of 920 kg/m3, some 1-3 km of excess core oblateness is consistent with the observed gravity. A wide range of moments of inertia is allowed, but models with low moments of inertia (i.e., more differentiation) require greater magnitudes of excess core topography to satisfy the observations.

  9. Io plasma torus ion composition: Voyager, Galileo, and Cassini

    Science.gov (United States)

    Nerney, Edward G.; Bagenal, Fran; Steffl, Andrew J.

    2017-01-01

    The Io torus produces ultraviolet emissions diagnostic of plasma conditions. We revisit data sets obtained by the Voyager 1, Galileo, and Cassini missions at Jupiter. With the latest version (8.0) of the CHIANTI atomic database we analyze UV spectra to determine ion composition. We compare ion composition obtained from observations from these three missions with a theoretical model of the physical chemistry of the torus by Delamere et al. (2005). We find ion abundances from the Voyager data similar to the Cassini epoch, consistent with the dissociation and ionization of SO2, but with a slightly higher average ionization state for sulfur, consistent with the higher electron temperature measured by Voyager. This reanalysis of the Voyager data produces a much lower oxygen:sulfur ratio than earlier analysis by Shemansky (1988), which was also reported by Bagenal (1994). We derive fractional ion compositions in the center of the torus to be S+/Ne 5%, S++/Ne 20%, S+++/Ne 5%, O+/Ne 20%, O++/Ne 3%, and Σ(On+)/Σ(Sn+) 0.8, leaving about 10-15% of the charge as protons. The radial profile of ion composition indicates a slightly higher average ionization state, a modest loss of sulfur relative to oxygen, and Σ(On+)/Σ(Sn+) 1.2 at about 8 RJ, beyond which the composition is basically frozen in. The Galileo observations of UV emissions from the torus suggest that the composition in June 1996 may have comprised a lower abundance of oxygen than usual, consistent with observations made at the same time by the EUVE satellite.

  10. Cassini RSS occultation observations of density waves in Saturn's rings

    Science.gov (United States)

    McGhee, C. A.; French, R. G.; Marouf, E. A.; Rappaport, N. J.; Schinder, P. J.; Anabtawi, A.; Asmar, S.; Barbinis, E.; Fleischman, D.; Goltz, G.; Johnston, D.; Rochblatt, D.

    2005-08-01

    On May 3, 2005, the first of a series of eight nearly diametric occultations by Saturn's rings and atmosphere took place, observed by the Cassini Radio Science (RSS) team. Simultaneous high SNR measurements at the Deep Space Network (DSN) at S, X, and Ka bands (λ = 13, 3.6, and 0.9 cm) have provided a remarkably detailed look at the radial structure and particle scattering behavior of the rings. By virtue of the relatively large ring opening angle (B=-23.6o), the slant path optical depth of the rings was much lower than during the Voyager epoch (B=5.9o), making it possible to detect many density waves and other ring features in the Cassini RSS data that were lost in the noise in the Voyager RSS experiment. Ultimately, diffraction correction of the ring optical depth profiles will yield radial resolution as small as tens of meters for the highest SNR data. At Ka band, the Fresnel scale is only 1--1.5 km, and thus even without diffraction correction, the ring profiles show a stunning array of density waves. The A ring is replete with dozens of Pandora and Prometheus inner Lindblad resonance features, and the Janus 2:1 density wave in the B ring is revealed with exceptional clarity for the first time at radio wavelengths. Weaker waves are abundant as well, and multiple occultation chords sample a variety of wave phases. We estimate the surface mass density of the rings from linear density wave models of the weaker waves. For stronger waves, non-linear models are required, providing more accurate estimates of the wave dispersion relation, the ring surface mass density, and the angular momentum exchange between the rings and satellite. We thank the DSN staff for their superb support of these complex observations.

  11. The INCA trial (Impact of NOD2 genotype-guided antibiotic prevention on survival in patients with liver Cirrhosis and Ascites): study protocol for a randomized controlled trial.

    Science.gov (United States)

    Casper, Markus; Mengel, Martin; Fuhrmann, Christine; Herrmann, Eva; Appenrodt, Beate; Schiedermaier, Peter; Reichert, Matthias; Bruns, Tony; Engelmann, Cornelius; Grünhage, Frank; Lammert, Frank

    2015-03-08

    Patients with liver cirrhosis have a highly elevated risk of developing bacterial infections that significantly decrease survival rates. One of the most relevant infections is spontaneous bacterial peritonitis (SBP). Recently, NOD2 germline variants were found to be potential predictors of the development of infectious complications and mortality in patients with cirrhosis. The aim of the INCA (Impact of NOD2 genotype-guided antibiotic prevention on survival in patients with liver Cirrhosis and Ascites) trial is to investigate whether survival of this genetically defined high-risk group of patients with cirrhosis defined by the presence of NOD2 variants is improved by primary antibiotic prophylaxis of SBP. The INCA trial is a double-blind, placebo-controlled clinical trial with two parallel treatment arms (arm 1: norfloxacin 400 mg once daily; arm 2: placebo once daily; 12-month treatment and observational period). Balanced randomization of 186 eligible patients with stratification for the protein content of the ascites (INCA trial is first in the field of hepatology aimed at rapidly transferring and validating information on individual genetic risk into clinical decision algorithms. German Clinical Trials Register DRKS00005616 . Registered 22 January 2014. EU Clinical Trials Register EudraCT 2013-001626-26 . Registered 26 January 2015.

  12. Calibration of the INCA model in a Mediterranean forested catchment: the effect of hydrological inter-annual variability in an intermittent stream

    Directory of Open Access Journals (Sweden)

    S. Bernal

    2004-01-01

    Full Text Available Mediterranean regions are characterised by a stream hydrology with a marked seasonal pattern and high inter-annual variability. Accordingly, soil N processes and leaching of solutes in Mediterranean regions also show a marked seasonality, occurring in pulses as soils re-wet following rain. The Integrated Nitrogen Catchment model (INCA was applied to Fuirosos, a Mediterranean catchment located in NE Spain using hydrological data and streamwater nitrate and ammonium concentrations collected from 1999 to 2002. This study tested the model under Mediterranean climate conditions and assessed the effect of the high inter-annual variability on the ability of INCA to simulate discharge and N fluxes. The model was calibrated for the whole three-year period and the n coefficients of determinion (r2 between simulated and observed data were 0.54 and 0.1 for discharge and nitrate temporal dynamics, respectively. Ammonium dynamics were simulated poorly and the linear regression between observed and simulated data was not significant statistically. To assess the effect of inter-annual variability on INCA simulations, the calibration process was run separately for two contrasting hydrological years: a dry year with a total rainfall of 525 mm and a wet year with a total of 871 mm. The coefficients of determination for the correlation between observed and simulated discharge for these two periods were 0.67 (p2 = 0.13 p2 = 0.56 p Keywords: environmental modelling, intermittent stream, Mediterranean climate, Fuirosos, hydrology, nitrate

  13. Inflight Characterization of the Cassini Spacecraft Propellant Slosh and Structural Frequencies

    Science.gov (United States)

    Lee, Allan Y.; Stupik, Joan

    2015-01-01

    While there has been extensive theoretical and analytical research regarding the characterization of spacecraft propellant slosh and structural frequencies, there have been limited studies to compare the analytical predictions with measured flight data. This paper uses flight telemetry from the Cassini spacecraft to get estimates of high-g propellant slosh frequencies and the magnetometer boom frequency characteristics, and compares these values with those predicted by theoretical works. Most Cassini attitude control data are available at a telemetry frequency of 0.5 Hz. Moreover, liquid sloshing is attenuated by propellant management device and attitude controllers. Identification of slosh and structural frequency are made on a best-effort basis. This paper reviews the analytical approaches that were used to predict the Cassini propellant slosh frequencies. The predicted frequencies are then compared with those estimated using telemetry from selected Cassini burns where propellant sloshing was observed (such as the Saturn Orbit Insertion burn).

  14. The Geodesy of the Main Saturnian Satellites from Range Rate Measurements of the Cassini Spacecraft

    Science.gov (United States)

    Ducci, M.; Iess, L.; Armstrong, J. W.; Asmar, S. W.; Jacobson, R. A.; Lunine, J. I.; Racioppa, P.; Rappaport, N. J.; Stevenson, D. J.; Tortora, P.

    2012-03-01

    During Cassini's eight-year tour in the saturnian system, the gravity field of the main satellites was inferred from range rate measurements of the spacecraft. Here we present our latest results and an overview of our analysis methods.

  15. Revised Full-Disk Spectra by Cassini-VIMS of the Saturnian Minor Icy Moons

    Science.gov (United States)

    Filacchione, G.; Cuzzi, J. N.; Clark, R. N.; Buratti, B. J.; Capaccioni, F.; Tosi, F.; Coradini, A.; Cerroni, P.; Adriani, A.; Cruikshank, D. P.; Jaumann, R.; Stephan, K.; Brown, R. H.; Nicholson, P. D.; Baines, K. H.; Nelson, R. M.; McCord, T. B.

    2009-03-01

    This abstract concern with a detailed re-analysis of the disk-integrated spectra of the minor moons of Saturn (Atlas, Prometheus, Pandora, Janus, Epimetheus, Calypso and Telesto) obtained by Cassini-VIMS.

  16. Precise Pointing for Radio Science Occultations and Radar Mapping During the Cassini Mission at Saturn

    Science.gov (United States)

    Burk, Thomas A.

    2015-01-01

    This paper discusses the implementation challenges and lessons learned from radar and radio science pointing observations during the Cassini mission at Saturn. Implementation of the precise desired pointing reveals key issues in the ground system, the flight system, and the pointing paradigm itself. To achieve accurate pointing on some observations, specific workarounds had to be implemented and folded into the sequence development process. Underlying Cassini's pointing system is a remarkable construct known as Inertial Vector Propagation.

  17. O cuidado especializado do egresso da residência em enfermagem do Instituto Nacional de Câncer - INCA La atención especializada del egreso de la residencia en enfermería del Instituto Nacional del Cáncer - INCA The specialized care of the egress from the residence in nursing of the National Institute of Cancer - INCA

    Directory of Open Access Journals (Sweden)

    Carlos Joelcio de Moraes Santana

    2007-09-01

    Full Text Available O objeto do estudo é o cuidado de enfermagem prestado pelos egressos da residência em enfermagem do INCA. Com objetivo de caracterizar a prática dos egressos da residência em enfermagem no CEMO (Centro de Transplante de Medula Óssea. Utilizaram-se os conceitos de especialista de Patrícia Benner e da United Kingdom Council Center (UKCC. Trata-se de uma pesquisa qualitativa realizada no CEMO em julho de 2004. Os sujeitos do estudo foram nove enfermeiros egressos da residência em enfermagem, da área de oncologia clínica, atuantes no CEMO desde 1991, data do início das contratações dos egressos. Utilizou-se a técnica de Grupo Focal para coletar os dados. A análise seguiu a orientações de análise temática, segundo Minayo. Os resultados evidenciaram a categoria "Cuidado Especializado do Egresso da Residência", que abrangeu temas relacionados com protocolo/tratamento/farmacologia, prescrição de enfermagem, orientação e experiência, e esperança e complexidade. Concluiu-se, portanto, que o trabalho realizado pelos egressos da residência de enfermagem no CEMO é especializado.El objeto del estudio es el cuidado de enfermería prestado por los egresos de la residencia en enfermería del INCA. El objetivo fue caracterizar la práctica de los egresos de la residencia en enfermería en el CEMO (Centro de Trasplante de Medula Ósea. Se utilizaron los conceptos de especialista de Patrícia Benner y de la United Kingdom Council Center (UKCC. Pesquisa cualitativa realizada en el CEMO en julio de 2004. Los sujetos del estudio fueron nueve enfermeros egresos de la residencia en enfermería, del área de oncología clínica, actuantes en el CEMO desde 1991, fecha del inicio de contrataciones de los egresos. Fue utilizada la técnica del Grupo Focal para colectar los datos. Se utilizó la técnica de análisis temática, en la perspectiva de Minayo. Fue identificada la categoría "El Cuidado Especializado del Egreso de la Residencia", que

  18. Optical properties of Titan's aerosols: comparison between DISR/Huygens observations and VIMS/Cassini solar occultation observations

    Science.gov (United States)

    Marmuse, Florian; Sotin, Christophe; Lawrence, Kenneth J.; Brown, Robert H.; Baines, Kevin; Buratti, Bonnie; Clark, Roger Nelson; Nicholson, Philip D.

    2016-10-01

    Titan, the only satellite with a dense atmosphere, presents a hydrocarbon cycle that includes the formation and sedimentation of organic aerosols. The optical properties of Titan's haze inferred from measurement of the Huygens probe were recently revisited by Doose et al. (Icarus, 2016). The present study uses the solar occultation observations in equatorial regions of Titan that have been acquired by the Visual and Infrared Mapping Spectrometer (VIMS) onboard the Cassini spacecraft to infer similar information in a broader wavelength range. Preliminary studies have proven the interest of those solar occultation data in the seven atmospheric windows to constrain the aerosol number density, but could not directly compare with the Descent Imager and Spectral Radiometer (DISR) data because models predict that the density profile vary with latitude. The present study compares the DISR measurements of aerosol extinction coefficients and the solar occultation data acquired by the VIMS instrument onboard Cassini. These sets of data differ in their acquisition method and time, spectral range, and altitude: the DISR measurements have been taken in 2005, along a vertical line of sight, in the visible spectral range (490-950nm) and under 140km of altitude. The relevant solar occultation data at equator have been acquired in 2009, along a horizontal line of sight, in the IR range (0.9-5.1µm), with sun light scanning all altitudes for a long enough wavelength, namely in the five-micron atmospheric window. These sets of data have been analyzed previously, separately and using different models. Here, we present a cross analysis of these sets of data, that allows us to test the different models describing the density profile of aerosols. In addition to providing wavelength dependence of the extinction coefficient, the comparison allows us to assess the impact of refraction in Titan's atmosphere. It also provides optical depth and scattering properties that are crucial information

  19. Cholos, incas y fusionistas: El nuevo Perú y la globalización de lo andino

    Directory of Open Access Journals (Sweden)

    Annelou Ypeij

    2013-04-01

    Full Text Available Abstract:   Cholos, incas and fusionistas: The New Peru and the Globalization of 'Lo Andino'This Exploration deals with the cultural changes in Peru from the year 2000. Peru has become a society with more economic, political, social and global opportunities. Within this context, significant cultural changes can be noted. This essay explores cultural expressions such as the weaving associations of the women of Chinchero, the Peruvian cuisine and the rock band Uchpa. All have in common that they reinterpret 'lo andino', or what it is to be Andean, and that they integrate globalized elements. Based on this, a new identity becomes apparent which surpasses the known categories of ethnicity and class.Resumen:Esta exploración trata sobre los cambios culturales en Perú a partir del año 2000. Perú se ha convertido en una sociedad con más oportunidades económicas, políticas, sociales y globales. En este contexto se pueden notar cambios culturales significantes. El ensayo explora expresiones culturales como las asociaciones de tejidos de las mujeres de Chinchero, la gastronomía peruana y la banda de rock Uchpa. Todas tienen en común que reinterpretan lo andino y que integran elementos globalizados. Basándose en ello, surge una nueva identidad que sobrepasa las conocidas categorías de etnicidad y de clase.

  20. Simulating nitrogen budgets in complex farming systems using INCA: calibration and scenario analyses for the Kervidy catchment (W. France

    Directory of Open Access Journals (Sweden)

    P. Durand

    2004-01-01

    Full Text Available The integrated nitrogen model INCA (Integrated Nitrogen in Catchments was used to analyse the nitrogen dynamics in a small rural catchment in Western France. The agrosystem studied is very complex, with: extensive use of different organic fertilisers, a variety of crop rotations, a structural excess of nitrogen (i.e. more animal N produced by the intensive farming than the N requirements of the crops and pastures, and nitrate retention in both hydrological stores and riparian zones. The original model features were adapted here to describe this complexity. The calibration results are satisfactory, although the daily variations in stream nitrate are not simulated in detail. Different climate scenarios, based on observed climate records, were tested; all produced a worsening of the pollution in the short term. Scenarios of alternative agricultural practices (reduced fertilisation and catch crops were also analysed, suggesting that a reduction by 40% of the fertilisation combined with the introduction of catch crops would be necessary to stop the degradation of water quality. Keywords: diffuse pollution, nitrate, climate change, model

  1. PERSiST: a flexible rainfall-runoff modelling toolkit for use with the INCA family of models

    Science.gov (United States)

    Futter, M. N.; Erlandsson, M. A.; Butterfield, D.; Whitehead, P. G.; Oni, S. K.; Wade, A. J.

    2014-02-01

    Runoff generation processes and pathways vary widely between catchments. Credible simulations of solute and pollutant transport in surface waters are dependent on models which facilitate appropriate, catchment-specific representations of perceptual models of the runoff generation process. Here, we present a flexible, semi-distributed landscape-scale rainfall-runoff modelling toolkit suitable for simulating a broad range of user-specified perceptual models of runoff generation and stream flow occurring in different climatic regions and landscape types. PERSiST (the Precipitation, Evapotranspiration and Runoff Simulator for Solute Transport) is designed for simulating present-day hydrology; projecting possible future effects of climate or land use change on runoff and catchment water storage; and generating hydrologic inputs for the Integrated Catchments (INCA) family of models. PERSiST has limited data requirements and is calibrated using observed time series of precipitation, air temperature and runoff at one or more points in a river network. Here, we apply PERSiST to the river Thames in the UK and describe a Monte Carlo tool for model calibration, sensitivity and uncertainty analysis.

  2. Transmutation of minor actinides in high and representative neutron fluxes: the mini-INCA and MEGAPIE projects

    Energy Technology Data Exchange (ETDEWEB)

    Letourneau, A.; Chabod, S.; Marie, F.; Ridikas, D.; Toussaint, J.C.; Veyssiere, C. [CEA/DSM/DAPNIA Saclay, Gif-sur-Yvette (France); Blandin, C. [CEA/DEN/DER/SPEX Cadarache - Saint-Paul-lez-Durances (France); Mutti, P. [Inst. Laue-Langevin, Grenoble (France)

    2003-07-01

    In the framework of nuclear waste transmutation studies, the Mini-INCA project has been initiated at CEA/DSM with objectives to determine optimal conditions for transmutation and incineration of minor actinides (MA) in high intensity neutron fluxes. Our experimental tools based on alpha- and gamma-spectroscopy of the samples and the development of micro fission chambers could gather either microscopic information on nuclear reactions (total or partial cross sections for neutron capture and/or fission reactions) or macroscopic information on transmutation and incineration potentials. Neutron capture cross sections of selected actinides ({sup 241}Am, {sup 242}Am, {sup 242}Pu, {sup 237}Np) have already been measured at ILL, showing some discrepancies when compared to evaluated data libraries but in overall good agreement with recent data. The studies and possibilities offer by the MEGAPIE project to assess neutronic performances of a 1 MW spallation target and the incineration of MA in a representative neutron flux of a spallation source are also discussed. (orig.)

  3. Exploring inner structure of Titan's dunes from Cassini Radar observations

    Science.gov (United States)

    Sharma, P.; Heggy, E.; Farr, T. G.

    2013-12-01

    Linear dunes discovered in the equatorial regions of Titan by the Cassini-Huygens mission are morphologically very similar to many terrestrial linear dune fields. These features have been compared with terrestrial longitudinal dune fields like the ones in Namib desert in western Africa. This comparison is based on the overall parallel orientation of Titan's dunes to the predominant wind direction on Titan, their superposition on other geomorphological features and the way they wrap around topographic obstacles. Studying the internal layering of dunes has strong implications in understanding the hypothesis for their origin and evolution. In Titan's case, although the morphology of the dunes has been studied from Cassini Synthetic Aperture Radar (SAR) images, it has not been possible to investigate their internal structure in detail as of yet. Since no radar sounding data is available for studying Titan's subsurface yet, we have developed another technique to examine the inner layering of the dunes. In this study, we utilize multiple complementary radar datasets, including radar imaging data for Titan's and Earth's dunes and Ground Penetrating Radar (GPR)/radar sounding data for terrestrial dunes. Based on dielectric mixing models, we suggest that the Cassini Ku-band microwaves should be able to penetrate up to ~ 3 m through Titan's dunes, indicating that the returned radar backscatter signal would include contributions from both surface and shallow subsurface echoes. This implies that the shallow subsurface properties can be retrieved from the observed radar backscatter (σ0). In our analysis, the variation of the radar backscatter as a function of dune height is used to provide an insight into the layering in Titan's dunes. We compare the variation of radar backscatter with elevation over individual dunes on Titan and analogous terrestrial dunes in three sites (Great Sand Sea, Siwa dunes and Qattaniya dunes) in the Egyptian Sahara. We observe a strong, positive

  4. Luminescence Instrumentation

    DEFF Research Database (Denmark)

    Jain, Mayank; Bøtter-Jensen, Lars

    2014-01-01

    This chapter gives an introduction to instrumentation for stimulated luminescence studies, with special focus on luminescence dating using the natural dosimeters, quartz and feldspars. The chapter covers basic concepts in luminescence detection, and thermal and optical stimulation, and reference...

  5. Cassini observations of ionospheric plasma in Saturn's magnetotail lobes.

    Science.gov (United States)

    Felici, M; Arridge, C S; Coates, A J; Badman, S V; Dougherty, M K; Jackman, C M; Kurth, W S; Melin, H; Mitchell, D G; Reisenfeld, D B; Sergis, N

    2016-01-01

    Studies of Saturn's magnetosphere with the Cassini mission have established the importance of Enceladus as the dominant mass source for Saturn's magnetosphere. It is well known that the ionosphere is an important mass source at Earth during periods of intense geomagnetic activity, but lesser attention has been dedicated to study the ionospheric mass source at Saturn. In this paper we describe a case study of data from Saturn's magnetotail, when Cassini was located at ≃ 2200 h Saturn local time at 36 RS from Saturn. During several entries into the magnetotail lobe, tailward flowing cold electrons and a cold ion beam were observed directly adjacent to the plasma sheet and extending deeper into the lobe. The electrons and ions appear to be dispersed, dropping to lower energies with time. The composition of both the plasma sheet and lobe ions show very low fluxes (sometimes zero within measurement error) of water group ions. The magnetic field has a swept-forward configuration which is atypical for this region, and the total magnetic field strength is larger than expected at this distance from the planet. Ultraviolet auroral observations show a dawn brightening, and upstream heliospheric models suggest that the magnetosphere is being compressed by a region of high solar wind ram pressure. We interpret this event as the observation of ionospheric outflow in Saturn's magnetotail. We estimate a number flux between (2.95 ± 0.43) × 10(9) and (1.43 ± 0.21) × 10(10) cm(-2) s(-1), 1 or about 2 orders of magnitude larger than suggested by steady state MHD models, with a mass source between 1.4 ×10(2) and 1.1 ×10(3) kg/s. After considering several configurations for the active atmospheric regions, we consider as most probable the main auroral oval, with associated mass source between 49.7 ±13.4 and 239.8 ±64.8 kg/s for an average auroral oval, and 10 ±4 and 49 ±23 kg/s for the specific auroral oval morphology found during this event. It is not clear how

  6. Saturn Ring Radiation Environment for the Cassini Grand Finale Orbits

    Science.gov (United States)

    Cooper, John F.; Kollmann, Peter; Johnson, Robert E.; Roussos, Elias; Sittler, Edward C.; Sturner, Steven J.

    2016-10-01

    Grand Finale (proximal) orbits of Cassini from April to September 2017 will provide an unprecedented opportunity for further in-situ exploration of the energetic radiation environment primarily arising from galactic cosmic ray interactions with the main rings. Improved modeling of these interactions contributes to ring mass properties, radiation chemistry, and source modeling for trapped radiation within and beyond the rings. Our new GEANT simulations show that these interactions produce very substantial fluxes of secondary gamma rays, neutrons, electrons, protons, and more short-lived particles. Cosmic ray albedo neutron decay from ring neutron emissions provides the primary source of trapped protons near and above 10 MeV in the radiation belts extending from beyond the F ring to the orbit of Tethys. Fluxes of these high-energy trapped protons increased as expected with declining solar activity from 2004 through 2009, consistent with decreasing modulation of the galactic cosmic ray protons and heavier ions by the solar wind. In 2017 solar activity and modulation will again be declining from earlier maximum levels in 2012 - 2014, while solar illumination of the rings will be near solstice levels. There may then be similarities in the ring radiation and plasma environment to conditions in 2004. In comparison, the 1979 traversal of the main rings by Pioneer 11 occurred during peak solar activity but declining cosmic ray flux. The questions are then what radiation environment we might expect to find during the Grand Finale orbits, how would the Cassini MIMI LEMMS sensor respond to this environment, and how might these new measurements change our understanding of the rings? During SOI flyover of the rings, LEMMS nominal data showed intensities higher than those from Pioneer 11 to an extent that cannot be explained by the updated interaction model. LEMMS more likely responded to penetrating high-energy radiation at energies outside its nominal ranges for electrons and

  7. Cassini observations of ionospheric plasma in Saturn's magnetotail lobes

    Science.gov (United States)

    Felici, M.; Arridge, C. S.; Coates, A. J.; Badman, S. V.; Dougherty, M. K.; Jackman, C. M.; Kurth, W. S.; Melin, H.; Mitchell, D. G.; Reisenfeld, D. B.; Sergis, N.

    2016-01-01

    Studies of Saturn's magnetosphere with the Cassini mission have established the importance of Enceladus as the dominant mass source for Saturn's magnetosphere. It is well known that the ionosphere is an important mass source at Earth during periods of intense geomagnetic activity, but lesser attention has been dedicated to study the ionospheric mass source at Saturn. In this paper we describe a case study of data from Saturn's magnetotail, when Cassini was located at ≃ 2200 h Saturn local time at 36 RS from Saturn. During several entries into the magnetotail lobe, tailward flowing cold electrons and a cold ion beam were observed directly adjacent to the plasma sheet and extending deeper into the lobe. The electrons and ions appear to be dispersed, dropping to lower energies with time. The composition of both the plasma sheet and lobe ions show very low fluxes (sometimes zero within measurement error) of water group ions. The magnetic field has a swept-forward configuration which is atypical for this region, and the total magnetic field strength is larger than expected at this distance from the planet. Ultraviolet auroral observations show a dawn brightening, and upstream heliospheric models suggest that the magnetosphere is being compressed by a region of high solar wind ram pressure. We interpret this event as the observation of ionospheric outflow in Saturn's magnetotail. We estimate a number flux between (2.95 ± 0.43) × 109 and (1.43 ± 0.21) × 1010 cm-2 s-1, 1 or about 2 orders of magnitude larger than suggested by steady state MHD models, with a mass source between 1.4 ×102 and 1.1 ×103 kg/s. After considering several configurations for the active atmospheric regions, we consider as most probable the main auroral oval, with associated mass source between 49.7 ±13.4 and 239.8 ±64.8 kg/s for an average auroral oval, and 10 ±4 and 49 ±23 kg/s for the specific auroral oval morphology found during this event. It is not clear how much of this mass is

  8. Pickup ions at Dione and Enceladus: Cassini Plasma Spectrometer simulations

    Science.gov (United States)

    Sittler, Ed C.; Johnson, R. E.; Jurac, S.; Richardson, J. D.; McGrath, M.; Crary, F.; Young, D. T.; Nordholt, J. E.

    2004-01-01

    Voyager images of the icy satellites of Saturn, Dione and Enceladus, suggest that they may have been geologically active and are not only composed of ice. Recent observations by the Hubble Space Telescope have shown the presence of ozone at both Dione and Rhea, which also implies the presence of molecular oxygen at these bodies. Observations of Ariel, Europa, Ganymede, and Callisto indicate the presence of CO2, so its presence on the Saturnian satellites is also expected. The Cassini Plasma Spectrometer (CAPS) will provide the capability to determine the global composition of these bodies by measuring the pickup ions produced by the ionization of their sputter-produced atmospheres. We will present a model of these atmospheres and associated pickup ions and demonstrate CAPS ability to distinguish the freshly produced picked up ions from the ambient plasma. Such ions are expected to form a ring distribution that will have a uniquely different energy-angle dependence than the ambient plasma ions. In the case of Dione we expect the potential for a moderate strength interaction for which both Voyager 1 and Pioneer 11 spacecraft measured ion cyclotron waves centered on the Dione L shell and near the equatorial plane. SKR radio emissions also displayed emissions occurring at the orbital period of Dione which could indicate some intrinsic activity due to Dione. So again, something interesting may be going on at Dione. Since Enceladus, or material in orbit near Enceladus, may be the source of the E-ring, some surprises may be encountered during its close encounter with the Cassini spacecraft. In the case of Dione we will show that a wake pass at 500 km altitude is more than an order of magnitude better than an upstream pass at 500 km altitude. Pickup ion detection for minor ion species such as NH3+ is possible for 500 km altitude wake pass but not for ≈500 km altitude upstream pass at closest approach. For navigation reasons a 100 km pass is not allowed. Therefore it is

  9. Titan Extinction Profiles Observed by Cassini Radio Occultations and Implications

    Science.gov (United States)

    Marouf, Essam; French, Richard; Flasar, F. Michael; Schinder, Paul J.; Rappaport, Nicole J.

    Three monochromatic and phase-coherent radio signals of wavelength = 0.9, 3.6, and 13 cm (Ka-, X-, and S-bands), were propagated by Cassini through the neutral atmosphere of Titan and the refracted signals were observed on the Earth. Abel inversion of observed changes in the signal frequency is used to recover the refractivity profile of the atmosphere, hence estimate the expected loss in signal strength due to defocusing of the radio signal by differential refraction. The refractive defocusing component (wavelength independent, in principle) is then removed from the actual measured signal strength profiles yielding the "true" signal extinction due to absorption and scattering integrated along the propagation path. Abel inversion of the integrated intensity profiles, tempered to combat noise contribution, yields localized estimates of the extinction coefficient (absorbtivity) as a function of altitude, or the extinction profiles. The initial radio measurements are diffraction-limited. We extend Fresnel transform based diffraction reconstruction procedures developed for radio occultation observations of planetary rings to remove diffraction effects from the initial radio measurements. The procedures are tested using idealized models of simple isothermal atmospheric profile extending above a hard-limb (knife-edge) model. Reconstruction of the simulated "observed" diffraction-limited data shows good agreement with the assumed atmospheric profile and the location of the hard-limb for a range of model parameters. We then apply a similar approach to the actual measured data. Strong wavelength-dependent extinction coefficient profile behavior is observed. Its large-scale structure appears well modeled by predictions based on N2-N2 collision-induced gaseous absorption for Titan's physical conditions. Interesting localized features of yet unexplained origin are also observed. Because the spatial scales of the extinction profile features are relatively large compared with

  10. Analysis and interpretation of Cassini Titan radar altimeter echoes

    Science.gov (United States)

    Zebker, Howard A.; Gim, Yonggyu; Callahan, Philip; Hensley, Scott; Lorenz, Ralph; Cassini Radar Team

    2009-03-01

    The Cassini spacecraft has acquired 25 radar altimeter elevation profiles along Titan's surface as of April 2008, and we have analyzed 18 of these for which there are currently reconstructed ephemeris data. Altimeter measurements were collected at spatial footprint sizes from 6-60 km along ground tracks of length 400-3600 km. The elevation profiles yield topographic information at this resolution with a statistical height accuracy of 35-50 m and kilometer-scale errors several times greater. The data exhibit significant variations in terrain, from flat regions with little topographic expression to very rugged Titanscapes. The bandwidth of the transmitted waveform admits vertical resolution of the terrain height to 35 m at each observed location on the surface. Variations in antenna pointing and changes in surface statistics cause the range-compressed radar echoes to exhibit strong systematic and time-variable biases of hundreds of meters in delay. It is necessary to correct the received echoes for these changes, and we have derived correction algorithms such that the derived echo profiles are accurate at the 100 m level for off-nadir pointing errors of 0.3° and 0.6°, for leading edge and echo centroid estimators, respectively. The leading edge of the echo yields the elevation of the highest points on the surface, which we take to be the peaks of any terrain variation. The mean value of the echo delay is more representative of the mean elevation, so that the difference of these values gives an estimate of any local mountain heights. Finding locations where these values diverge indicates higher-relief terrain. Elevation features are readily seen in the height profiles. Several of the passes show mountains of several hundred m altitude, spread over 10's or even 100's of km in spatial extent, so that slopes are very small. Large expanses of sub-100 m topography are commonplace on Titan, so it is rather smooth in many locations. Other areas exhibit more relief

  11. Multi-Instrument Studies of an Arc in Saturn's G Ring

    Science.gov (United States)

    Hedman, M. M.; Burns, J. A.; Tiscareno, M. S.; Nicholson, P. D.; Porco, C. C.; Jones, G. H.; Roussos, E.; Krupp, N.; Paranicas, C.

    2006-12-01

    The G ring is a narrow, faint ring located between the orbits of Janus and Mimas. The first evidence for material in this region came from a series of charged particle absorptions detected by Pioneer 11 in 1979, and the ring itself was first imaged by the Voyager spacecraft. Now a combination of in-situ and optical remote sensing instruments onboard the Cassini spacecraft are providing new insights into the dynamics and origin of this obscure ring. During a pass over the G ring on day 248 of 2005, the MIMI instrument detected a deep, narrow charged particle absorption signature in the vicinity of the G ring. Similarly deep and narrow charged particle absorptions were not seen during Cassini's other passages near this region. The magnitude of the charged particle absorption on day 248 suggested either the presence of a solid body or a much higher particle density in the G ring than one might expect from other observations.Images obtained by the cameras onboard Cassini reveal that the likely explanation for this anomaly is a bright arc located on the inner edge of the G ring (around 167,500 km) and extending over 30 degrees in longitude. By tracking this arc over the first two years of the Cassini Mission, we have established that Cassini passed close to the arc on day 248 of 2005, and that Cassini was not near the arc during other passages near the G ring. The orbital period of the arc is 0.80813 day, corresponding to a semi-major axis of 167,496 km. This places the arc within 6 km of the Mimas 7:6 Co-rotation Eccentricity Resonance and within 12 km of the Mimas 7:6 Inner Lindblad Resonance. The arc is therefore likely confined in longitude by Mimas in the same way that the arcs in Neptune's ring are held in place by Galatea. Cassini now has the opportunity to study the dynamics of this sort of system in detail over a period of years. The arc may also be the source of the material for the rest of the G ring. A combination of photometric and spectroscopic data from

  12. Saturn's tropospheric particles phase function and spatial distribution from Cassini ISS 2010-11 observations

    Science.gov (United States)

    Pérez-Hoyos, Santiago; Sanz-Requena, José Francisco; Sánchez-Lavega, Agustín; Irwin, Patrick G. J.; Smith, Andrew

    2016-10-01

    The phase function describes the way particles scatter the incoming radiation. This is a fundamental piece of knowledge in order to understand how a planetary atmosphere scatters sunlight and so it has a profound influence in the retrieved atmospheric properties such as cloud height, particle density distribution and radiative forcing by aerosols. In this work we analyze data from the Imaging Science Subsystem (ISS) instrument onboard Cassini spacecraft to determine the particle phase function at blue (451 nm) and near infrared wavelengths (727-890 nm) of particles in the upper troposphere, where most of the incoming visible sunlight is scattered. In order to do so, we use observations taken in later 2010 and 2011 covering a broad range of phase angles from ∼10° to ∼160° in the blue (BL1) and near infrared filters associated with intermediate and deep methane absorption bands (MT2, CB2, MT3). Particles at all latitudes are found to be strongly forward scattering. The equatorial particles are in good agreement with laboratory measurements of 10 μm ammonia ice crystals, while mid- and sub-polar latitude particles may be similar to the equatorial particles, but they may also be consistent with 1 μm ellipsoids with moderate aspect ratios. Uncertainties due to limited phase coverage and parameter degeneracy prevent strong constraints of the particle shapes and sizes at these locations. Results for the particle phase function are also used to describe the spatial distribution of tropospheric particles both vertically and latitudinally in the Northern hemisphere.

  13. Dynamics of Saturn’s 2010 Great White Spot from high-resolution Cassini ISS observations

    Science.gov (United States)

    Hueso, Ricardo; Sánchez-Lavega, A.; del Río-Gaztelurrutia, T.

    2012-10-01

    On December 5th 2010 a storm erupted in Saturn’s North Temperate latitudes which were experiencing early spring season. The storm quickly developed to a planet-wide disturbance of the Great White Spot type. The ISS instrument onboard Cassini acquired its first images of the storm on 23th December 2010 and performed repeated observations with a variety of spatial resolutions over the nearly 10 months period the storm continued active. Here we present an analysis of two of the image sequences with better spatial resolution of the mature storm when it was fully developed and very active. We used an image correlation algorithm to measure the cloud motions obtained from images separated 20 minutes and obtained 16,000 wind tracers in a domain of 60 degrees longitude per 20 degrees in latitude. Intense zonal and meridional motions accompanied the storm and reached values of 120 m/s in particular regions of the active storm. The storm released a chain of anticyclonic and cyclonic vortices at planetocentric latitudes of 36° and 32° respectively. The short time difference between the images results in estimated wind uncertainties of 15 m/s that did not allow to perform a complete analysis of the turbulence and kinetic spectrum of the motions. We identify locations of the updrafts and link those with the morphology in different observing filters. The global behaviour of the storm was examined in images separated by 10 hours confirming the intensity of the winds and the global behaviour of the vortices. Acknowledgments: This work was supported by the Spanish MICIIN project AYA2009-10701 with FEDER funds, by Grupos Gobierno Vasco IT-464-07 and by Universidad País Vasco UPV/EHU through program UFI11/55.

  14. An Overview of Saturn Narrowband Radio Emissions Observed by Cassini RPWS

    Science.gov (United States)

    Ye, S.-Y.; Fischer, G.; Menietti, J. D.; Wang, Z.; Gurnett, D. A.; Kurth, W. S.

    Saturn narrowband (NB) radio emissions are detected between 3 and 70 kHz, with occurrence probability and wave intensity peaking around 5 kHz and 20 kHz. The emissions usually occur periodically for several days after intensification of Saturn kilometric radiation (SKR). Originally detected by the Voyagers, the extended duration of the Cassini mission and the improved capabilities of the Radio and Plasma Wave Science (RPWS) instrument have significantly advanced our knowledge about them. For example, RPWS measurements of the magnetic component have validated the electromagnetic nature of Saturn NB emissions. Evidences show that the 20 kHz NB emissions are generated by mode conversion of electrostatic upper hybrid waves on the boundary of the plasma torus, whereas direction-finding results point to a source in the auroral zone for the 5 kHz component. Similar to SKR, the 5 kHz NB emissions have a clock-like modulation and display two distinct modulation periods identical to the northern and southern hemisphere periods of SKR. Polarization measurements confirm that most NB emissions are propagating in the L-O mode, with the exception of second harmonic NB emissions. At high latitudes closer to the planet, RPWS detected right hand polarized Z-mode NB emissions below the local electron cyclotron frequency (f_ce), which are believed to be the source of the L-O mode NB emissions detected above the local f_ce. Although the energy source for the generation of the Z-mode waves is still unclear, linear growth rate calculations indicate that the observed plasma distributions are unstable to the growth of electrostatic cyclotron harmonic emission. Alternatively, electromagnetic Z-mode might be directly generated by the cyclotron maser instability. The source Z-mode waves, upon reflection, propagate to the opposite hemisphere before escaping through mode conversion, which could explain the fact that both rotational modulation periods of NB emissions are observable in each

  15. Morphology of Enceladus's craters by photometric studies with ISS/Cassini

    Science.gov (United States)

    Degiorgio, K.; Rodriguez, S.; Ferrari, C. C.; Brahic, A.

    2010-12-01

    The study of crater morphology (depth to diameter ratio) can bring valuable information on the structural properties of the surface and sub-surface of the impacted body. We report here on the analysis of images of the cratered terrains of the Saturn’s moon Enceladus recorded between 2005 and 2008 by the ISS instrument onboard the Cassini spacecraft. We used a 3D morphological model (Buratti and Veverka, 1985) coupled with a regolith scattering model (Hapke, 1993, 2001) in order to analyze the photometric behavior of a sample of a set of 50 Enceladus’ craters. This method enables us to verify the general photometric properties of Enceladus’ regolith (single scattering albedo and asymmetry factor in very good agreement with previous studies - e.g. Verbiscer and Veverka, 1994) and derive for the first time robust estimations of the craters’ depth. As previously done for other bodies (Schenk, 1989), we used this new information to plot the depth/diameter ratio as a function of the diameter for all the craters of our sample. Such a diagram allows to determine the presence of a transition diameter, which usually defines the transition between two regimes of crater formation (simple to complex craters) and is diagnostic of the structural properties of the crust. The value of the transition diameter for Enceladus is found close to the one of Mimas but slightly differs from the empirical general law derived by Schenk (1989) (inversely proportional to surface gravity), being globally lower than for other icy bodies. We will discuss the possible implications of such a low value on the Enceladus’s geological history and crust properties.

  16. NANODUST DETECTION BETWEEN 1 AND 5 AU USING CASSINI WAVE MEASUREMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Schippers, P.; Vernet, N. Meyer-; Lecacheux, A.; Belheouane, S.; Moncuquet, M. [LESIA—CNRS—Observatoire de Paris, 5 place Jules Janssen, F-92195 Meudon (France); Kurth, W. S. [Department of Physics and Astronomy, University of Iowa, Iowa City, IA (United States); Mann, I. [EISCAT Scientific Association, Kiruna, Sweden and Department of Physics Umeå University (Sweden); Mitchell, D. G. [Applied Physics Laboratory, John Hopkins University, Laurel, MD (United States); André, N. [IRAP, 9 Avenue du Colonel Roche, F-31028 Toulouse (France)

    2015-06-10

    The solar system contains solids of all sizes, ranging from kilometer-sized bodies to nano-sized particles. Nanograins have been detected in situ in the Earth's atmosphere, near cometary and giant planet environments, and more recently in the solar wind at 1 AU. The latter nanograins are thought to be formed in the inner solar system dust cloud, mainly through the collisional break-up of larger grains, and are then picked up and accelerated by the magnetized solar wind because of their large charge-to-mass ratio. In the present paper, we analyze the low frequency bursty noise identified in the Cassini radio and plasma wave data during the spacecraft cruise phase inside Jupiter's orbit. The magnitude, spectral shape, and waveform of this broadband noise are consistent with the signatures of the nano particles that traveled at solar wind speed and impinged on the spacecraft surface. Nanoparticles were observed whenever the radio instrument was turned on and able to detect them at different heliocentric distances between Earth and Jupiter, suggesting their ubiquitous presence in the heliosphere. We analyzed the radial dependence of the nanodust flux with heliospheric distance and found that it is consistent with the dynamics of nanodust originating from the inner heliosphere and picked up by the solar wind. The contribution of the nanodust produced in the asteroid belt appears to be negligible compared to the trapping region in the inner heliosphere. In contrast, further out, nanodust is mainly produced by the volcanism of active moons such as Io and Enceladus.

  17. The Evolution and Fate of Saturn's Stratospheric Vortex: Infrared Spectroscopy from Cassini

    Science.gov (United States)

    Fletcher, Leigh N.; Hesman, B. E.; Arhterberg, R. K.; Bjoraker, G.; Irwin, P. G. J.; Hurley, J.; Sinclair, J.; Gorius, N.; Orton, G. S.; Read, P. L.; Simon-Miller, A. A.; Flasar, F. M.

    2012-01-01

    The planet-encircling springtime storm in Saturn's troposphere (December 2010-July 2011) produced dramatic perturbations to stratospheric temperatures, winds and composition at mbar pressures that persisted long after the tropospheric disturbance had abated. Observations from the Cassini Composite Infrared Spectrometer (CIRS), supported by ground-based imaging from the VISIR instrument on the Very Large Telescope,is used to track the evolution of a large, hot stratospheric anticyclone between January 2011 and the present day. The evolutionary sequence can be divided into three phases: (I) the formation and intensification of two distinct warm airmasses near 0.5 mbar between 25 and 35N (one residing directly above the convective storm head) between January-April 2011, moving westward with different zonal velocities; (II) the merging of the warm airmasses to form the large single 'stratospheric beacon' near 40N between April and June 2011, dissociated from the storm head and at a higher pressure (2 mbar) than the original beacons; and (III) the mature phase characterized by slow cooling and longitudinal shrinkage of the anticyclone since July 2011, moving west with a near-constant velocity of 2.70+/-0.04 deg/day (-24.5+/-0.4 m/s at 40N). Peak temperatures of 220 K at 2 mbar were measured on May 5th 2011 immediately after the merger, some 80 K warmer than the quiescent surroundings. Thermal winds hear calculations in August 2011 suggest clockwise peripheral velocities of 200400 mls at 2 mbar, defining a peripheral collar with a width of 65 degrees longitude (50,000 km in diameter) and 25 degrees latitude. Stratospheric acetylene (C2H2) was uniformly enhanced by a factor of three within the vortex, whereas ethane (C2H6) remained unaffected. We will discuss the thermal and chemical characteristics of Saturn's beacon in its mature phase, and implications for stratospheric vortices on other giant planets.

  18. New constraints on Saturn's interior from Cassini astrometric data

    CERN Document Server

    Lainey, Valéry; Tajeddine, Radwan; Cooper, Nicholas J; Murray, Carl; Robert, Vincent; Tobie, Gabriel; Guillot, Tristan; Mathis, Stéphane; Remus, Françoise; Desmars, Josselin; Arlot, Jean-Eudes; De Cuyper, Jean-Pierre; Dehant, Véronique; Pascu, Dan; Thuillot, William; Poncin-Lafitte, Christophe Le; Zahn, Jean-Paul

    2015-01-01

    Using astrometric observations spanning more than a century and including a large set of Cassini data, we determine Saturn's tidal parameters through their current effects on the orbits of the eight main and four coorbital moons. We have used the latter to make the first determination of Saturn's Love number, $k_2=0.390 \\pm 0.024$, a value larger than the commonly used theoretical value of 0.341 (Gavrilov & Zharkov, 1977), but compatible with more recent models (Helled & Guillot, 2013) for which $k_2$ ranges from 0.355 to 0.382. Depending on the assumed spin for Saturn's interior, the new constraint can lead to a reduction of up to 80% in the number of potential models, offering great opportunities to probe the planet's interior. In addition, significant tidal dissipation within Saturn is confirmed (Lainey et al., 2012) corresponding to a high present-day tidal ratio $k_2/Q=(1.59 \\pm 0.74) \\times 10^{-4}$ and implying fast orbital expansions of the moons. This high dissipation, with no obvious variati...

  19. Determining Titan surface topography from Cassini SAR data

    Science.gov (United States)

    Stiles, Bryan W.; Hensley, Scott; Gim, Yonggyu; Bates, David M.; Kirk, Randolph L.; Hayes, Alex; Radebaugh, Jani; Lorenz, Ralph D.; Mitchell, Karl L.; Callahan, Philip S.; Zebker, Howard; Johnson, William T.K.; Wall, Stephen D.; Lunine, Jonathan I.; Wood, Charles A.; Janssen, Michael; Pelletier, Frederic; West, Richard D.; Veeramacheneni, Chandini

    2009-01-01

    A technique, referred to as SARTopo, has been developed for obtaining surface height estimates with 10 km horizontal resolution and 75 m vertical resolution of the surface of Titan along each Cassini Synthetic Aperture Radar (SAR) swath. We describe the technique and present maps of the co-located data sets. A global map and regional maps of Xanadu and the northern hemisphere hydrocarbon lakes district are included in the results. A strength of the technique is that it provides topographic information co-located with SAR imagery. Having a topographic context vastly improves the interpretability of the SAR imagery and is essential for understanding Titan. SARTopo is capable of estimating surface heights for most of the SAR-imaged surface of Titan. Currently nearly 30% of the surface is within 100 km of a SARTopo height profile. Other competing techniques provide orders of magnitude less coverage. We validate the SARTopo technique through comparison with known geomorphological features such as mountain ranges and craters, and by comparison with co-located nadir altimetry, including a 3000 km strip that had been observed by SAR a month earlier. In this area, the SARTopo and nadir altimetry data sets are co-located tightly (within 5-10 km for one 500 km section), have similar resolution, and as expected agree closely in surface height. Furthermore the region contains prominent high spatial resolution topography, so it provides an excellent test of the resolution and precision of both techniques.

  20. Constraints on Mimas' interior from Cassini ISS libration measurements.

    Science.gov (United States)

    Tajeddine, R; Rambaux, N; Lainey, V; Charnoz, S; Richard, A; Rivoldini, A; Noyelles, B

    2014-10-17

    Like our Moon, the majority of the solar system's satellites are locked in a 1:1 spin-orbit resonance; on average, these satellites show the same face toward the planet at a constant rotation rate equal to the satellite's orbital rate. In addition to the uniform rotational motion, physical librations (oscillations about an equilibrium) also occur. The librations may contain signatures of the satellite's internal properties. Using stereophotogrammetry on Cassini Image Science Subsystem (ISS) images, we measured longitudinal physical forced librations of Saturn's moon Mimas. Our measurements confirm all the libration amplitudes calculated from the orbital dynamics, with one exception. This amplitude depends mainly on Mimas' internal structure and has an observed value of twice the predicted one, assuming hydrostatic equilibrium. After considering various possible interior models of Mimas, we argue that the satellite has either a large nonhydrostatic interior, or a hydrostatic one with an internal ocean beneath a thick icy shell. Copyright © 2014, American Association for the Advancement of Science.

  1. On Cas A, Cassini, Comets and King Charles

    CERN Document Server

    Soria, Roberto; Ohtsuka, Yasuyo

    2013-01-01

    We re-examine the long-standing problem of the date of the Cassiopeia A supernova (SN), in view of recent claims that it might be the 1630 "noon-star" seen at the birth of King Charles II. We do not support this identification, based on the expected brightness of a Type-IIb SN (too faint to be seen in daylight), the extrapolated motion of the ejecta (inconsistent with a date earlier than 1650), the lack of any scientific follow-up observations, the lack of any mention of it in Asian archives. The origin of the 1630 noon-star event (if real) remains a mystery; there was a bright comet in 1630 June but no evidence to determine whether or not it was visible in daylight. Instead, we present French reports about a 4th-magnitude star discovered by Cassini in Cassiopeia in or shortly before 1671, which was not seen before or since. The brightness is consistent with what we expect for the Cas A SN; the date is consistent with the extrapolated motion of the ejecta. We argue that this source could be the long-sought SN...

  2. Fluvial channels on Titan: Initial Cassini RADAR observations

    Science.gov (United States)

    Lorenz, R.D.; Lopes, R.M.; Paganelli, F.; Lunine, J.I.; Kirk, R.L.; Mitchell, K.L.; Soderblom, L.A.; Stofan, E.R.; Ori, G.; Myers, M.; Miyamoto, H.; Radebaugh, J.; Stiles, B.; Wall, S.D.; Wood, C.A.

    2008-01-01

    Cassini radar images show a variety of fluvial channels on Titan's surface, often several hundreds of kilometers in length. Some (predominantly at low- and mid-latitude) are radar-bright and braided, resembling desert washes where fines have been removed by energetic surface liquid flow, presumably from methane rainstorms. Others (predominantly at high latitudes) are radar-dark and meandering and drain into or connect polar lakes, suggesting slower-moving flow depositing fine-grained sediments. A third type, seen predominantly at mid- and high latitudes, have radar brightness patterns indicating topographic incision, with valley widths of up to 3 km across and depth of several hundred meters. These observations show that fluvial activity occurs at least occasionally at all latitudes, not only at the Huygens landing site, and can produce channels much larger in scale than those observed there. The areas in which channels are prominent so far amount to about 1% of Titan's surface, of which only a fraction is actually occupied by channels. The corresponding global sediment volume inferred is not enough to account for the extensive sand seas. Channels observed so far have a consistent large-scale flow pattern, tending to flow polewards and eastwards. ?? 2008.

  3. Probing Saturn's tropospheric cloud with Cassini/VIMS

    CERN Document Server

    Barstow, Joanna K; Fletcher, Leigh N; Giles, Rohini S; Merlet, Cecile

    2016-01-01

    In its decade of operation the Cassini mission has allowed us to look deep into Saturn's atmosphere and investigate the processes occurring below its enshrouding haze. We use Visual and Infrared Mapping Spectrometer (VIMS) 4.6-5.2 micron data from early in the mission to investigate the location and properties of Saturn's cloud structure between 0.6 and 5 bars. We average nightside spectra from 2006 over latitude circles and model the spectral limb darkening using the NEMESIS radiative transfer and retrieval tool. We present our best-fit deep cloud model for latitudes between -40 and 50 degrees, along with retrieved abundances for NH3, PH3 and AsH3. We find an increase in NH3 abundance at the equator, a cloud base at ~2.3 bar and no evidence for cloud particles with strong absorption features in the 4.6-5.2 micron wavelength range, all of which are consistent with previous work. Non-scattering cloud models assuming a composition of either NH3 or NH4SH, with a scattering haze overlying, fit limb darkening curv...

  4. SOLAR OCCULTATION BY TITAN MEASURED BY CASSINI/UVIS

    Energy Technology Data Exchange (ETDEWEB)

    Capalbo, Fernando J.; Benilan, Yves [Laboratoire Interuniversitaire des Systemes Atmospheriques (LISA), UMR 7583 du CNRS, Universites Paris Est Creteil (UPEC) and Paris Diderot - UPD, 61 avenue du General de Gaulle, 94010 Creteil Cedex (France); Yelle, Roger V.; Koskinen, Tommi T.; Sandel, Bill R. [Lunar and Planetary Laboratory, University of Arizona, 1629 E. University Blvd., Tucson, AZ 85721 (United States); Holsclaw, Gregory M.; McClintock, William E., E-mail: fernando.capalbo@lisa.u-pec.fr [Laboratory for Atmospheric and Space Physics, University of Colorado, 3665 Discovery Drive, Boulder, CO 80303 (United States)

    2013-04-01

    We present the first published analysis of a solar occultation by Titan's atmosphere measured by the Ultraviolet Imaging Spectrograph on board Cassini. The data were measured during flyby T53 in 2009 April and correspond to latitudes between 21 Degree-Sign and 28 Degree-Sign south. The analysis utilizes the absorption of two solar emission lines (584 A and 630 A) in the ionization continuum of the N{sub 2} absorption cross section and solar emission lines around 1085 A where absorption is due to CH{sub 4}. The measured transmission at these wavelengths provides a direct estimate of the N{sub 2} and CH{sub 4} column densities along the line of sight from the spacecraft to the Sun, which we inverted to obtain the number densities. The high signal-to-noise ratio of the data allowed us to retrieve density profiles in the altitude range 1120-1400 km for nitrogen and 850-1300 km for methane. We find an N{sub 2} scale height of {approx}76 km and a temperature of {approx}153 K. Our results are in general agreement with those from previous work, although there are some differences. Particularly, our profiles agree, considering uncertainties, with the density profiles derived from the Voyager 1 Ultraviolet Spectrograph data, and with in situ measurements by the Ion Neutral Mass Spectrometer with revised calibration.

  5. (abstract) Cassini MLI Balnkets High-Temperature Exposure Tests

    Science.gov (United States)

    Lin, Edward I.; Stultz, James W.

    1995-01-01

    The trajectory required for the Cassini spacecraft to reach Saturn will subject the spacecraft to a 0.61 AU temperature environment at perihelion. Temperatures on some sunlit blanket surfaces at 0.61 AU can reach levels that are beyond the service capability of the conventional Mylar/Dacron net MLI. The majority of the blanket surfaces, however, will experience temperatures with an upper bound of 250(deg) C. The maximum allowable temperature for Mylar/Dacron net is determined to be 220(deg)C. Kapton can withstand temperatures in excess of 400(deg) C; however, the high cost of embossed Kapton relative to Mylar/Dacron net requires a baseline design which includes a standard layup and a high-temperature layup. The high-temperature layup is utilized at a limited number of locations, while at least 90% of the blankets are of the standard layup. The verification of both layups' capability to meet all temperature requirements has been accomplished by a comprehensive test program which addressed their high-temperature survivability, effective emittance, and optical and electrical properties. This paper focuses on the high-temperature exposure tests which helped define the hybrid standard layup, and which demonstrated the adequacy of both layups in withstanding their respective thermal environments.

  6. On Cas A, Cassini, Comets, and King Charles

    Science.gov (United States)

    Soria, Roberto; Balestrieri, Riccardo; Ohtsuka, Yasuyo

    2013-03-01

    We re-examine the long-standing problem of the date of the Cassiopeia A supernova (SN), in view of recent claims that it might be the 1630 'noon-star' seen at the birth of King Charles II. We do not support this identification, based on the expected brightness of a Type-IIb SN (too faint to be seen in daylight), the extrapolated motion of the ejecta (inconsistent with a date earlier than 1650), the lack of any scientific follow-up observations, the lack of any mention of it in Asian archives. The origin of the 1630 noon-star event (if real) remains a mystery; there was a bright comet in 1630 June but no evidence to determine whether or not it was visible in daylight. Instead, we present French reports about a fourth-magnitude star discovered by Cassini in Cassiopeia in or shortly before 1671, which was not seen before or since. The brightness is consistent with what we expect for the Cas A SN; the date is consistent with the extrapolated motion of the ejecta. We argue that this source could be the long-sought SN.

  7. The Shape of Saturn's Huygens Ringlet Viewed by Cassini ISS

    CERN Document Server

    Spitale, Joseph N

    2015-01-01

    A new model for the shape of the prominent eccentric ringlet in the gap exterior to Saturn's B-ring is developed based on Cassini observations taken over about 8 years. Unlike previous treatments, the new model treats each edge of the ringlet separately. The Keplerian component of the model is consistent with results derived from Voyager observations, and $m=2$ modes forced by the nearby Mimas 2:1 Lindblad resonance are seen. Additionally, a free $m=2$ mode is seen on the outer edge of the ringlet. Significant irregular structure that cannot be described using normal-mode analysis is seen on the ringlet edges as well. Particularly on the inner edge, that structure remains coherent over multi-year intervals, moving at the local Keplerian rate. We interpret the irregular structure as the signature of embedded massive bodies. The long coherence time suggests the responsible bodies are concentrated near the edge of the ringlet. Long wake-like structures originate from two locations on the inner edge of the ringle...

  8. Saturn's aurora observed by the Cassini camera at visible wavelengths

    CERN Document Server

    Dyudina, Ulyana A; Ewald, Shawn P; Wellington, Danika

    2015-01-01

    The first observations of Saturn's visible-wavelength aurora were made by the Cassini camera. The aurora was observed between 2006 and 2013 in the northern and southern hemispheres. The color of the aurora changes from pink at a few hundred km above the horizon to purple at 1000-1500 km above the horizon. The spectrum observed in 9 filters spanning wavelengths from 250 nm to 1000 nm has a prominent H-alpha line and roughly agrees with laboratory simulated auroras. Auroras in both hemispheres vary dramatically with longitude. Auroras form bright arcs between 70 and 80 degree latitude north and between 65 and 80 degree latitude south, which sometimes spiral around the pole, and sometimes form double arcs. A large 10,000-km-scale longitudinal brightness structure persists for more than 100 hours. This structure rotates approximately together with Saturn. On top of the large steady structure, the auroras brighten suddenly on the timescales of a few minutes. These brightenings repeat with a period of about 1 hour....

  9. The Structure of Enceladus' Plume from Cassini Occultation Observations

    Science.gov (United States)

    Hansen, C. J.; Esposito, L. W.; Buffington, B. B.; Colwell, J.; Hendrix, A. R.; Meinke, B. K.; Shemansky, D. E.; Stewart, I.; West, R. A.

    2011-12-01

    Cassini's Ultraviolet Imaging Spectrograph (UVIS) has observed 2 stellar and one solar occultation by Enceladus' water vapor plume. These observations have established that water is the primary constituent of the plume, allowed us to calculate the flux of water coming from the plume, and detected super-sonic jets of gas imbedded within the plume [1]. On 19 October 2011 two stars (epsilon and zeta Orionis) will simultaneously be occulted by the plume, and the signal of the two will be in separate pixels on the detector. This is a tangential occultation that will provide a horizontal cut through the plume at two altitudes. The two stars are separated by 24 mrad, or ~20 km, with the lower altitude star 18 km above the limb at its closest point. The groundtrack is similar to the 2010 solar occultation, but viewed from the other side of the plume. Results from this new data set with implications for the vertical structure of the plume and jets will be presented.

  10. Cassini in Titan's tail: CAPS observations of plasma escape

    Science.gov (United States)

    Coates, A. J.; Wellbrock, A.; Lewis, G. R.; Arridge, C. S.; Crary, F. J.; Young, D. T.; Thomsen, M. F.; Reisenfeld, D. B.; Sittler, E. C., Jr.; Johnson, R. E.; Szego, K.; Bebesi, Z.; Jones, G. H.

    2012-05-01

    We present observations of CAPS electron and ion spectra during Titan distant tail crossings at 5,000-10,000 km altitude by the Cassini spacecraft. In common with closer tail encounters, we identify ionospheric plasma in the tail. Some of the electron spectra indicate a direct magnetic connection to Titan's dayside ionosphere due to the presence of ionospheric photoelectrons. Ion observations reveal heavy (m/q˜ 16 and 28) and light (m/q = 1-2) ion populations streaming into the tail. Using the distant tail encounters T9, T75 and T63, we estimate total plasma loss rates from Titan via this process of (4.2, 0.96 and 2.3) × 1024 ions s-1 respectively for the three encounters, values which are in agreement with some simulations but slightly lower than earlier estimates based on non-differential techniques. Using the mass-separated data, this corresponds to mass loss rates of (8.9, 1.6, 4.0) × 1025 amu s-1 for T9, T75 and T63 respectively, an average loss rate of ˜7 tonnes per Earth day. Remarkably, all of the tail encounters studied here indicate a split tail feature, indicating that this may be a common feature in Titan's interaction with Saturn's magnetosphere.

  11. Reconstructing the Life of an Unknown (ca. 500 Years-Old South American Inca) Mummy – Multidisciplinary Study of a Peruvian Inca Mummy Suggests Severe Chagas Disease and Ritual Homicide

    Science.gov (United States)

    Panzer, Stephanie; Peschel, Oliver; Haas-Gebhard, Brigitte; Bachmeier, Beatrice E.; Pusch, Carsten M.; Nerlich, Andreas G.

    2014-01-01

    The paleopathological, paleoradiological, histological, molecular and forensic investigation of a female mummy (radiocarbon dated 1451–1642 AD) provides circumstantial evidence for massive skull trauma affecting a young adult female individual shortly before death along with chronic infection by Trypanosoma cruzi (Chagas disease). The mummy (initially assumed to be a German bog body) was localized by stable isotope analysis to South America at/near the Peruvian/Northern Chilean coast line. This is further supported by New World camelid fibers attached to her plaits, typical Inca-type skull deformation and the type of Wormian bone at her occiput. Despite an only small transverse wound of the supraorbital region computed tomography scans show an almost complete destruction of face and frontal skull bones with terrace-like margins, but without evidence for tissue reaction. The type of destruction indicates massive blunt force applied to the center of the face. Stable isotope analysis indicates South American origin: Nitrogen and hydrogen isotope patterns indicate an extraordinarily high marine diet along with C4-plant alimentation which fits best to the coastal area of Pacific South America. A hair strand over the last ten months of her life indicates a shift to a more “terrestric” nutrition pattern suggesting either a move from the coast or a change in her nutrition. Paleoradiology further shows extensive hypertrophy of the heart muscle and a distended large bowel/rectum. Histologically, in the rectum wall massive fibrosis alternates with residual smooth muscle. The latter contains multiple inclusions of small intracellular parasites as confirmed by immunohistochemical and molecular ancient DNA analysis to represent a chronic Trypanosoma cruzi infection. This case shows a unique paleopathological setting with massive blunt force trauma to the skull nurturing the hypothesis of a ritual homicide as previously described in South American mummies in an individual

  12. Reconstructing the life of an unknown (ca. 500 years-old South American Inca) mummy--multidisciplinary study of a Peruvian Inca mummy suggests severe Chagas disease and ritual homicide.

    Science.gov (United States)

    Panzer, Stephanie; Peschel, Oliver; Haas-Gebhard, Brigitte; Bachmeier, Beatrice E; Pusch, Carsten M; Nerlich, Andreas G

    2014-01-01

    The paleopathological, paleoradiological, histological, molecular and forensic investigation of a female mummy (radiocarbon dated 1451-1642 AD) provides circumstantial evidence for massive skull trauma affecting a young adult female individual shortly before death along with chronic infection by Trypanosoma cruzi (Chagas disease). The mummy (initially assumed to be a German bog body) was localized by stable isotope analysis to South America at/near the Peruvian/Northern Chilean coast line. This is further supported by New World camelid fibers attached to her plaits, typical Inca-type skull deformation and the type of Wormian bone at her occiput. Despite an only small transverse wound of the supraorbital region computed tomography scans show an almost complete destruction of face and frontal skull bones with terrace-like margins, but without evidence for tissue reaction. The type of destruction indicates massive blunt force applied to the center of the face. Stable isotope analysis indicates South American origin: Nitrogen and hydrogen isotope patterns indicate an extraordinarily high marine diet along with C4-plant alimentation which fits best to the coastal area of Pacific South America. A hair strand over the last ten months of her life indicates a shift to a more "terrestric" nutrition pattern suggesting either a move from the coast or a change in her nutrition. Paleoradiology further shows extensive hypertrophy of the heart muscle and a distended large bowel/rectum. Histologically, in the rectum wall massive fibrosis alternates with residual smooth muscle. The latter contains multiple inclusions of small intracellular parasites as confirmed by immunohistochemical and molecular ancient DNA analysis to represent a chronic Trypanosoma cruzi infection. This case shows a unique paleopathological setting with massive blunt force trauma to the skull nurturing the hypothesis of a ritual homicide as previously described in South American mummies in an individual that

  13. Reconstructing the life of an unknown (ca. 500 years-old South American Inca mummy--multidisciplinary study of a Peruvian Inca mummy suggests severe Chagas disease and ritual homicide.

    Directory of Open Access Journals (Sweden)

    Stephanie Panzer

    Full Text Available The paleopathological, paleoradiological, histological, molecular and forensic investigation of a female mummy (radiocarbon dated 1451-1642 AD provides circumstantial evidence for massive skull trauma affecting a young adult female individual shortly before death along with chronic infection by Trypanosoma cruzi (Chagas disease. The mummy (initially assumed to be a German bog body was localized by stable isotope analysis to South America at/near the Peruvian/Northern Chilean coast line. This is further supported by New World camelid fibers attached to her plaits, typical Inca-type skull deformation and the type of Wormian bone at her occiput. Despite an only small transverse wound of the supraorbital region computed tomography scans show an almost complete destruction of face and frontal skull bones with terrace-like margins, but without evidence for tissue reaction. The type of destruction indicates massive blunt force applied to the center of the face. Stable isotope analysis indicates South American origin: Nitrogen and hydrogen isotope patterns indicate an extraordinarily high marine diet along with C4-plant alimentation which fits best to the coastal area of Pacific South America. A hair strand over the last ten months of her life indicates a shift to a more "terrestric" nutrition pattern suggesting either a move from the coast or a change in her nutrition. Paleoradiology further shows extensive hypertrophy of the heart muscle and a distended large bowel/rectum. Histologically, in the rectum wall massive fibrosis alternates with residual smooth muscle. The latter contains multiple inclusions of small intracellular parasites as confirmed by immunohistochemical and molecular ancient DNA analysis to represent a chronic Trypanosoma cruzi infection. This case shows a unique paleopathological setting with massive blunt force trauma to the skull nurturing the hypothesis of a ritual homicide as previously described in South American mummies in an

  14. Uso de las ideas matemáticas y científicas de los Incas, en la enseñanza-aprendizaje de la geometría

    Directory of Open Access Journals (Sweden)

    César E. Salas Valverde

    2008-02-01

    Full Text Available Considerando una aproximación Etnomatemática, entendida como el estudio de los procesos matemáticos,símbolos, jergas, mitologías, razonamiento, practicados por grupos culturales identificados; valoramos las posibilidades didácticas que pueden desprenderse del uso de las ideas matemáticas utilizadas en la cultura Inca.El trabajo presenta dos partes. Una valoración del uso de la matemática en la cultura Inca y otra relativa a sugerencias didácticas. Se propone por ejemplo: que los alumnos reconozcan qué conocimientos, patrones, objetos o formas geométricas usaban los incas en sus diversas manifestaciones culturales y tecnológicas. Apartir de estas “tareas" podemos introducir al estudiante en el hermoso mundo de la geometría, haciendo que aprendan de un modo bastante intuitivo y natural.

  15. Uso de las Ideas Matemáticas y Científicas de los Incas, en la Enseñanza Aprendizaje de la Geometría.

    Directory of Open Access Journals (Sweden)

    Enrique Huapaya Gómez

    2008-01-01

    Full Text Available Considerando una aproximación Etnomatemática, entendida como el estudio de los procesos matemáticos, símbolos, jergas, mitologías, razonamiento, practicados por grupos culturales identificados4; valoramos las posibilidades didácticas que pueden desprenderse del uso de las ideas matemáticas utilizadas en la cultura Inca. El trabajo presenta dos partes. Una valoración del uso de la matemática en la cultura Inca y otra relativa a sugerencias didácticas. Se propone por ejemplo: que los alumnos reconozcan qué conocimientos, patrones, objetos o formas geométricas usaban los incas en sus diversas manifestaciones culturales y tecnológicas. A partir de estas "tareas" podemos introducir al estudiante en el hermoso mundo de la geometría, haciendo que aprendan de un modo bastante intuitivo y natural5.

  16. La geología, evolución geomorfológica y geodinámica externa de la ciudad inca de Machupicchu, Cusco-Perú Geology, Morphologic Evolution and Geodynamic Phenomena of Machupicchu Inca City, Cusco-Perú

    Directory of Open Access Journals (Sweden)

    Víctor Carlotto

    2009-12-01

    Full Text Available La ciudad inca de Machupicchu se sitúa dentro del santuario histórico de Machupicchu, en la Cordillera Oriental del sur del Perú; está a 2.450 m s.n.m., 500 m por encima del río Urubamba que corta la cordillera y forma un cañón, con clima cálido de ceja de selva. La geología, con afloramientos graníticos y bloques de granitos apilados, forma un paisaje de caos granítico, sobre el que fue construida la ciudad inca de Machupicchu. La evolución geológica plio-cuaternaria muestra una exhumación muy rápida de la cordillera, la que condicionó los fenómenos geodinámicos que dieron la geomorfología actual y los fenómenos geodinámicos que afectan a la ciudad inca de Machupicchu. Durante la ocupación inca, los andenes con sistemas de drenajes y las construcciones con techos permitían una evacuación eficaz de las abundantes aguas de lluvias; sin embargo, este no es el caso actualmente, ya que las construcciones no tienen techo y gran parte de los drenajes no funcionan, generando infiltraciones, asentamientos, erosión superficial, sufusión, derrumbes, caída de rocas y deslizamientos superficiales. Los levantamientos geológicos al detalle y los estudios específicos en varias zonas (conjuntos permiten dar recomendaciones para una adecuada evacuación de las aguas pluviales y evitar las infiltraciones o la erosión superficial, mediante drenajes y pisos impermeables.

  17. Instrumented SSH

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, Scott; Campbell, Scott

    2009-05-27

    NERSC recently undertook a project to access and analyze Secure Shell (SSH) related data. This includes authentication data such as user names and key fingerprints, interactive session data such as keystrokes and responses, and information about noninteractive sessions such as commands executed and files transferred. Historically, this data has been inaccessible with traditional network monitoring techniques, but with a modification to the SSH daemon, this data can be passed directly to intrusion detection systems for analysis. The instrumented version of SSH is now running on all NERSC production systems. This paper describes the project, details about how SSH was instrumented, and the initial results of putting this in production.

  18. Cassini Attitude Control Operations Flight Rules and How They are Enforced

    Science.gov (United States)

    Burk, Thomas; Bates, David

    2008-01-01

    The Cassini spacecraft was launched on October 15, 1997 and arrived at Saturn on June 30, 2004. It has performed detailed observations and remote sensing of Saturn, its rings, and its satellites since that time. Cassini deployed the European-built Huygens probe which descended through the Titan atmosphere and landed on its surface on January 14, 2005. Operating the Cassini spacecraft is a complex scientific, engineering, and management job. In order to safely operate the spacecraft, a large number of flight rules were developed. These flight rules must be enforced throughout the lifetime of the Cassini spacecraft. Flight rules are defined as any operational limitation imposed by the spacecraft system design, hardware, and software, violation of which would result in spacecraft damage, loss of consumables, loss of mission objectives, loss and/or degradation of science, and less than optimal performance. Flight rules require clear description and rationale. Detailed automated methods have been developed to insure the spacecraft is continuously operated within these flight rules. An overview of all the flight rules allocated to the Cassini Attitude Control and Articulation Subsystem and how they are enforced is presented in this paper.

  19. Cassini Attitude Control Operations Flight Rules and How They are Enforced

    Science.gov (United States)

    Burk, Thomas; Bates, David

    2008-01-01

    The Cassini spacecraft was launched on October 15, 1997 and arrived at Saturn on June 30, 2004. It has performed detailed observations and remote sensing of Saturn, its rings, and its satellites since that time. Cassini deployed the European-built Huygens probe which descended through the Titan atmosphere and landed on its surface on January 14, 2005. Operating the Cassini spacecraft is a complex scientific, engineering, and management job. In order to safely operate the spacecraft, a large number of flight rules were developed. These flight rules must be enforced throughout the lifetime of the Cassini spacecraft. Flight rules are defined as any operational limitation imposed by the spacecraft system design, hardware, and software, violation of which would result in spacecraft damage, loss of consumables, loss of mission objectives, loss and/or degradation of science, and less than optimal performance. Flight rules require clear description and rationale. Detailed automated methods have been developed to insure the spacecraft is continuously operated within these flight rules. An overview of all the flight rules allocated to the Cassini Attitude Control and Articulation Subsystem and how they are enforced is presented in this paper.

  20. Active instruments

    DEFF Research Database (Denmark)

    Lim, Miguel Antonio; Ørberg, Jakob Williams

    2017-01-01

    ) show the dynamic nature of policy processes, and (3) consider the search for policy reference points among the different actors. We present rankers in motion, policies in motion, and finally the complex nature of the ranking device that needs to be both a relevant and malleable policy instrument...

  1. Modeling the terrestrial N processes in a small mountain catchment through INCA-N: A case study in Taiwan.

    Science.gov (United States)

    Lu, Meng-Chang; Chang, Chung-Te; Lin, Teng-Chiu; Wang, Lih-Jih; Wang, Chiao-Ping; Hsu, Ting-Chang; Huang, Jr-Chuan

    2017-09-01

    Riverine dissolved inorganic nitrogen (DIN) is an important indicator of trophic status of aquatic ecosystems. High riverine DIN export in Taiwan, ~3800kg-Nkm(-2)yr(-1), which is ~18 times higher than the global average, urges the need of thorough understanding of N cycling processes. We applied INCA-N (Integrated Nitrogen Catchment Model) to simulate riverine DIN export and infer terrestrial N processes using weekly rainwater and streamwater samples collected at the Fushan Experimental Forest (FEF) of northern Taiwan. Results showed that the modeled discharge and nitrate export are in good agreement with observations, suggesting the validity of our application. Based on our modeling, the three main N removal processes, in the order of descending importance, were plant uptake, riverine N transport and denitrification at FEF. The high plant uptake rate, 4920kg-Nkm(-2)yr(-1), should have led to accumulation of large biomass but biomass at FEF was relatively small compared to other tropical forests, likely due to periodic typhoon disruptions. The low nitrate concentration but high DIN export highlights the importance of hydrological control over DIN export, particularly during typhoons. The denitrification rate, 750kg-Nkm(-2)yr(-1), at FEF was also low compared to other tropical forest ecosystems, likely resulting from quick water drainage through the coarse-loamy top soils. The high DIN export to atmospheric deposition ratio, 0.45, suggests that FEF may be in advanced stages of N excess. This simulation provides useful insights for establishing monitoring programs and improves our understanding N cycling in subtropical watersheds. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Cirrus cloud occurrence as function of ambient relative humidity: a comparison of observations obtained during the INCA experiment

    Directory of Open Access Journals (Sweden)

    J. Ström

    2003-01-01

    Full Text Available Based on in-situ observations performed during the Interhemispheric differences in cirrus properties from anthropogenic emissions (INCA experiment, we introduce and discuss the cloud presence fraction (CPF defined as the ratio between the number of data points determined to represent cloud at a given ambient relative humidity over ice (RHI divided by the total number of data points at that value of RHI. The CPFs are measured with four different cloud probes. Within similar ranges of detected particle sizes and concentrations, it is shown that different cloud probes yield results that are in good agreement with each other. The CPFs taken at Southern Hemisphere (SH and Northern Hemisphere (NH midlatitudes differ from each other. Above ice saturation, clouds occurred more frequently during the NH campaign. Local minima in the CPF as a function of RHI are interpreted as a systematic underestimation of cloud presence when cloud particles become invisible to cloud probes. Based on this interpretation, we find that clouds during the SH campaign formed preferentially at RHIs between 140 and 155%, whereas clouds in the NH campaign formed at RHIs somewhat below 130%. The data show that interstitial aerosol and ice particles coexist down to RHIs of 70-90%, demonstrating that the ability to distinguish between different particle types in cirrus conditions depends on the sensors used to probe the aerosol/cirrus system. Observed distributions of cloud water content differ only slightly between the NH and SH campaigns and seem to be only weakly, if at all, affected by the freezing aerosols.

  3. Leão Hebreu e Garcilaso de la Vega, o Inca: um encontro à sombra de Platão

    Directory of Open Access Journals (Sweden)

    Maria José de Queiroz

    2012-03-01

    Full Text Available Para celebrar o quinto centenário do Descobrimento, à luz da expulsão dos judeus da Espanha, procuramos na antiga Sefarad – a pátria medieval dos hebreus que se instalaram na Península Ibérica – um sefardita de origem e de sangue que nos testemunhasse dupla fidelidade: à Hispânia e à sua fé. Devemos ao exílio o encontro de Leão Hebreu (1460/1465-1521 com o seu tradutor Garcilaso de la Vega, o Inca (1540-1615.

  4. EFECTOS DEL ESTRÉS HÍDRICO EN LA ASIMILACIÓN DEL NITRÓGENO EN PLANTAS DE TOMATE CV INCA 9-1

    OpenAIRE

    Inés M. Reynaldo; Ivette Pérez; E. Jerez; J. M. Dell'Amico

    2002-01-01

    El objetivo de esta investigación fue comparar los efectos que provocan el déficit hídrico y la inundación sobre la asimilación foliar del nitrógeno en plantas de tomate (Lycopersicon esculentum Mill.) cv INCA 9-1. Los experimentos se realizaron en condiciones semicontroladas y cuando las plantas se encontraban en la etapa de floración se les aplicaron tres tratamientos por un período de 72 horas: riego normal (control), suspensión del riego (déficit hídrico) y suministro de agua hasta 1 cm p...

  5. Tupamaro de Caxamarca: tonadas sobre la muerte del Inca Atahualpa contenidas en el códice Martínez Compañón (1782-85)

    OpenAIRE

    2011-01-01

    A lo largo de la Colonia se va construyendo una memoria de la historia de los pueblos andinos que considera al Imperio incaico como su principal referente y a la figura del Inca1 como su símbolo natural. La narración de los hechos de la historia incaica, en especial aquellos relativos a la conquista española, generaron el mito de la muerte del Inca2, a la cual habrán contribuido colonizados y colonizadores. Durante el siglo XVIII serán numerosas las representaciones teatral-musicales de estos...

  6. Cassini Imaging of Auroral Emissions on the Galilean Satellites

    Science.gov (United States)

    Geissler, P.; McEwen, A.; Porco, C.

    2001-05-01

    Cassini captured several sequences of images showing Io, Europa and Ganymede while the moons were eclipsed by Jupiter. Io was the best studied of the satellites, with 4 eclipses successfully recorded. Earlier eclipse imaging by Galileo (Geissler et al., Science 295, 870-874) had shown colorful atmospheric emissions from Io and raised questions concerning their temporal variability and the identity of the emitting species. With its high data rate and numerous filter combinations, Cassini was able to fill some of the gaps in our knowledge of Io's visible aurorae. Io's bright equatorial glows were detected at previously unknown wavelengths and were also seen in motion. One eclipse took place on 12/29/2000 while Io was far from the plasma torus center. The pair of equatorial glows near the sub-Jupiter and anti-Jupiter points appeared about equal in brightness and changed little in location or intensity over a two hour period. Io crossed the plasma torus center during the next eclipse on 1/01/2001, as it passed through System III magnetic longitudes from 250 to 303 degrees. The equatorial glows were seen to shift in latitude during this eclipse, tracking the tangent points of the jovian magnetic field lines. This behaviour is similar to that observed for ultraviolet and other atomic emissions, and confirms that these visible glows are powered by Birkeland currents connecting Io and Jupiter. The eclipse on 1/05/2001 provided the best spectral measurements of the aurorae. The equatorial glows were detected at near ultraviolet wavelengths, consistent with their interpretation as molecular SO2 emissions. More than 100 kR were recorded in the ISS UV3 filter (300-380 nm) along with a similar intensity in BL1 (290-500 nm), comparable to Galileo estimates. At least 50 kR were detected in UV2 images (265-330 nm). No detection was made in UV1 (235-280 nm), allowing us to place an upper limit of about 100 kR. A new detection of the equatorial glows was made in the IR1 band (670

  7. Constraining the Enceladus plume using numerical simulation and Cassini data

    Science.gov (United States)

    Yeoh, Seng Keat; Li, Zheng; Goldstein, David B.; Varghese, Philip L.; Levin, Deborah A.; Trafton, Laurence M.

    2017-01-01

    Since its discovery, the Enceladus plume has been subjected to intense study due to the major effects that it has on the Saturnian system and the window that it provides into the interior of Enceladus. However, several questions remain and we attempt to answer some of them in this work. In particular, we aim to constrain the H2O production rate from the plume, evaluate the relative importance of the jets and the distributed sources along the Tiger Stripes, and make inferences about the source of the plume by accurately modeling the plume and constraining the model using the Cassini INMS and UVIS data. This is an extension of a previous work (Yeoh, S.K., et al. [2015] Icarus, 253, 205-222) in which we only modeled the collisional part of the Enceladus plume and studied its important physical processes. In this work, we propagate the plume farther into space where the flow has become free-molecular and the Cassini INMS and UVIS data were sampled. Then, we fit this part of the plume to the INMS H2O density distributions sampled along the E3, E5 and E7 trajectories and also compare some of the fit results with the UVIS measurements of the plume optical depth collected during the solar occultation observation on 18 May 2010. We consider several vent conditions and source configurations for the plume. By constraining our model using the INMS and UVIS data, we estimate H2O production rates of several hundred kgs-1: 400-500 kg/s during the E3 and E7 flybys and ∼900 kg/s during the E5 flyby. These values agree with other estimates and are consistent with the observed temporal variability of the plume over the orbital period of Enceladus (Hedman, M.M., et al. [2013] Nature, 500, 182-184). In addition, we determine that one of the Tiger Stripes, Cairo, exhibits a local temporal variability consistent with the observed overall temporal variability of the plume. We also find that the distributed sources along the Tiger Stripes are likely dominant while the jets provide a

  8. Statistical study of Saturn's auroral electron properties with Cassini/UVIS FUV spectral images

    Science.gov (United States)

    Gustin, J.; Grodent, D.; Radioti, A.; Pryor, W.; Lamy, L.; Ajello, J.

    2017-03-01

    Cassini MAG and CAPS/ELS instruments. However, several auroral regions are characterized by relatively high and low energy flux, suggesting that additional processes such as plasma injections or magnetic reconnections must be accounted for to explain the emission in these regions. The Lyα/H2 ratio technique can be used to build maps of from single spectral images. As expected, preliminary results show that the spatial distribution of is not uniform, as seen on Jupiter. Our study reveals that a fraction of the aurora is due to very low energy electrons (<1 keV). Even in this case, comparisons between observed and modeled spectra show that 100 eV is a suitable value to represent the average energy of the secondary electrons.

  9. The composition of Titan's stratosphere from Cassini/CIRS mid-infrared spectra

    Science.gov (United States)

    Coustenis, Athena; Achterberg, Richard K.; Conrath, Barney J.; Jennings, Donald E.; Marten, André; Gautier, Daniel; Nixon, Conor A.; Flasar, F. Michael; Teanby, Nick A.; Bézard, Bruno; Samuelson, Robert E.; Carlson, Ronald C.; Lellouch, Emmanuel; Bjoraker, Gordon L.; Romani, Paul N.; Taylor, Fred W.; Irwin, Patrick G. J.; Fouchet, Thierry; Hubert, Augustin; Orton, Glenn S.; Kunde, Virgil G.; Vinatier, Sandrine; Mondellini, Jacqueline; Abbas, Mian M.; Courtin, Regis

    2007-07-01

    models. The D/H ratio in the methane on Titan has been determined from the CH 3D band at 1156 cm -1 and found to be 1.17-0.28+0.23×10. Implications of this deuterium enrichment, with respect to the protosolar abundance on the origin of Titan, are discussed. We compare our results with values retrieved by Voyager IRIS observations taken in 1980, as well as with more recent (1997) disk-averaged Infrared Space Observatory (ISO) results and with the latest Cassini-Huygens inferences from other instruments in an attempt to better comprehend the physical phenomena on Titan.

  10. Tupamaro de Caxamarca: tonadas sobre la muerte del Inca Atahualpa contenidas en el códice Martínez Compañón (1782-85 Tupamaro de Caxamarca: Tunes about the Death of the Inca Atahualpa contained in the Codex Martínez Compañón (1782-85

    Directory of Open Access Journals (Sweden)

    Tiziana Palmiero

    2011-12-01

    Full Text Available A lo largo de la Colonia se va construyendo una memoria de la historia de los pueblos andinos que considera al Imperio incaico como su principal referente y a la figura del Inca1 como su símbolo natural. La narración de los hechos de la historia incaica, en especial aquellos relativos a la conquista española, generaron el mito de la muerte del Inca2, a la cual habrán contribuido colonizados y colonizadores. Durante el siglo XVIII serán numerosas las representaciones teatral-musicales de estos hechos. El códice Martínez Compañón (1782-85 consta de nueve tomos con alrededor de 1.500 láminas en colores que ilustran los diferentes aspectos de la vida social y natural de la zona de Trujillo, Perú. Treinta y ocho láminas, incluidas en el tomo II, se refieren directa o indirectamente a la música de tradición oral de la época, las láminas numeradas -foliación original, E. está por "Estampa"- desde la E.176 hasta la E.193 contienen un total de veinte partituras. A primera vista el título de las dos tonadas: "E.188: Allegro tonada El tupamaro, Caxamarca" y "E.191 (b: Adagio tonada el Tuppamaro de caxa-marca" sugiere que el contenido de las mismas podría tener relación con los sucesos de Cajamarca, es decir, con la captura y muerte del Inca Atahualpa3. En el mismo tomo II se encuentran además dos láminas que representan la decapitación del Inca: "Danza de la degollación del Ynga E.172; E.173.". De ser así las dos tonadas podrían ser dos fragmentos musicales únicos de las representaciones teatrales antes mencionadas4. Durante el análisis de las dos partituras encontramos que éstas tendrían relación con otras partituras del mismo códice: "E. 191, Magestuoso Cachua la Despedida de Guamachuco"; "E. 190 Allegro tonada la brugita para cantar de Guamachuco" y "E.187, Andantino Tonada El Diamante, para baylar de Chachapoyas". Se trató de analogías musicales o textuales que permitieron crear un hilo conductor con los tr

  11. Transient surface liquid in Titan's south polar region from Cassini

    Science.gov (United States)

    Hayes, A.G.; Aharonson, O.; Lunine, J.I.; Kirk, R.L.; Zebker, H.A.; Wye, L.C.; Lorenz, R.D.; Turtle, E.P.; Paillou, P.; Mitri, Giuseppe; Wall, S.D.; Stofan, E.R.; Mitchell, K.L.; Elachi, C.

    2011-01-01

    Cassini RADAR images of Titan's south polar region acquired during southern summer contain lake features which disappear between observations. These features show a tenfold increases in backscatter cross-section between images acquired one year apart, which is inconsistent with common scattering models without invoking temporal variability. The morphologic boundaries are transient, further supporting changes in lake level. These observations are consistent with the exposure of diffusely scattering lakebeds that were previously hidden by an attenuating liquid medium. We use a two-layer model to explain backscatter variations and estimate a drop in liquid depth of approximately 1-m-per-year. On larger scales, we observe shoreline recession between ISS and RADAR images of Ontario Lacus, the largest lake in Titan's south polar region. The recession, occurring between June 2005 and July 2009, is inversely proportional to slopes estimated from altimetric profiles and the exponential decay of near-shore backscatter, consistent with a uniform reduction of 4 ± 1.3 m in lake depth. Of the potential explanations for observed surface changes, we favor evaporation and infiltration. The disappearance of dark features and the recession of Ontario's shoreline represents volatile transport in an active methane-based hydrologic cycle. Observed loss rates are compared and shown to be consistent with available global circulation models. To date, no unambiguous changes in lake level have been observed between repeat images in the north polar region, although further investigation is warranted. These observations constrain volatile flux rates in Titan's hydrologic system and demonstrate that the surface plays an active role in its evolution. Constraining these seasonal changes represents the first step toward our understanding of longer climate cycles that may determine liquid distribution on Titan over orbital time periods.

  12. Meteorology of Jupiter's Equatorial Hot Spots and Plumes from Cassini

    Science.gov (United States)

    Choi, David Sanghun; Showman, Adam P.; Vasavada, Ashwin R.; Simon-Miller, Amy A.

    2013-01-01

    We present an updated analysis of Jupiter's equatorial meteorology from Cassini observations. For two months preceding the spacecraft's closest approach, the Imaging Science Subsystem (ISS) onboard regularly imaged the atmosphere. We created time-lapse movies from this period in order to analyze the dynamics of equatorial hot spots and their interactions with adjacent latitudes. Hot spots are relatively cloud-free regions that emit strongly at 5 lm; improved knowledge of these features is crucial for fully understanding Galileo probe measurements taken during its descent through one. Hot spots are quasistable, rectangular dark areas on visible-wavelength images, with defined eastern edges that sharply contrast with surrounding clouds, but diffuse western edges serving as nebulous boundaries with adjacent equatorial plumes. Hot spots exhibit significant variations in size and shape over timescales of days and weeks. Some of these changes correspond with passing vortex systems from adjacent latitudes interacting with hot spots. Strong anticyclonic gyres present to the south and southeast of the dark areas appear to circulate into hot spots. Impressive, bright white plumes occupy spaces in between hot spots. Compact cirrus-like 'scooter' clouds flow rapidly through the plumes before disappearing within the dark areas. These clouds travel at 150-200 m/s, much faster than the 100 m/s hot spot and plume drift speed. This raises the possibility that the scooter clouds may be more illustrative of the actual jet stream speed at these latitudes. Most previously published zonal wind profiles represent the drift speed of the hot spots at their latitude from pattern matching of the entire longitudinal image strip. If a downward branch of an equatorially-trapped Rossby wave controls the overall appearance of hot spots, however, the westward phase velocity of the wave leads to underestimates of the true jet stream speed.

  13. Design and Analysis of RTGs for CRAF and Cassini Missions

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred; Noravian, Heros; Sankarankandath

    1990-11-30

    This report consists of two parts. Part 1 describes the development of novel analytical methods needed to predict the BOM performance and the subsequent performance degradation of the mutually obstructed RTGs for the CRAF and Cassini missions. Part II applies those methods to the two missions, presents the resultant predictions, and discusses their programmatic implications. The results indicate that JPL's original power demand goals could have been met with two standard GPHS RTGs for each mission. But subsequently JPL significantly increased both the power level and the mission duration for both missions, so that they can no longer by met by two standard RTGs. The resultant power gap must be closed either by reducing JPL's power demand (e.g., by decreasing contingency reserves) and/or by increasing the power system's output. One way under active consideration which more than meets the system power goal would be the addition of a third RTG for each mission. However, the author concluded that it may be possible to meet or closely approach the CRAF power demand goals with just two RTGs by relatively modest modification of their design and/or operating conditions. To explore that possibility, the effect of various modifications - either singly or in combination - was analyzed by Fairchild. The results indicate that modest modifications can meet or come very close to meeting the CRAF power goals with just two RTGs. Elimination of the third RTG would yield substantial cost and schedule savings. There are three copies in the file.

  14. The Global Geology of Titan from Cassini RADAR data

    Science.gov (United States)

    Lopes, Rosaly; Malaska, Michael J.

    The variety of geological processes on Titan is rivaled in our Solar System only on Earth. Results from the Cassini-Huygens mission obtained so far have revealed a wide range of geologic and climatological processes. We use data obtained by Cassini’s Titan Radar Mapper (13.78 GHz, lambda=2.17 cm) to analyze the distribution of different types of geologic processes occurring on Titan’s surface, both endogenic and exogenic, and to derive temporal relationships between these processes, at least at local scales. The distribution and interplay of geologic processes is important to provide constraints on models of the interior and of surface-atmosphere interactions. We mapped the SAR images in terms of characteristic morphology of geological features and their radar backscatter in order to determine possible emplacement sequences and the overall distribution of geologic processes. All the major planetary geologic processes - volcanism, tectonism, impact cratering and erosion - appear to have played a role in shaping Titan’s complex surface. This paper will review the distribution and relative ages of different geomorphologic units. While some units (craters, dunes, mountains, channels, lakes and seas) are well established in the literature, the presence of cryovolcanic features is still somewhat controversial, and the origin of undifferentiated plains (known as blandlands) is still mysterious. We now have over half of Titan’s surface imaged by SAR and the interpretation of these and other terrains is better constrained. The results from our latest analyses suggest that a sedimentary origin for the undifferentiated plains is the most likely. Cryovolcanism appears to have occurred on Titan, but it is not ubiquitous, and the major cryovolcanic area appears to be old, now partly covered by dunes. Titan’s surface shows a complex interaction between the surface and atmosphere, with erosional processes being driven by wind, liquids and dissolution.

  15. Cassini Radar at Titan : Evolving Studies of an Evolving World

    Science.gov (United States)

    Lorenz, Ralph D.

    2013-04-01

    The Cassini RADAR investigation continues to explore Titan : here I summarize some recent and ongoing developments. Geological interpretation of SAR imaging engages a wide community, in particular addressing Titan's dunes, lakes, seas and fluvial systems, impact craters and possible cryovolcanic features. Mapping of these features continues to suggest a dynamic world, with geologically-recent surface change due to tectonic, hydrological and aeolian processes. Mapping of fluvial channels and shoreline features suggests some tectonic controls and spatially-variable land/sea level changes. A despeckle filter applied to the images has proven popular for image interpretation, for example in resolving what may be star- and barchanoid dune morphologies which contrast with the dominant linear type. New observations in 2012 (T83, T84 and T86) place bounds on liquid accumulation in the northern polar regions - not expected to be substantial for another couple of years - and have highlighted a possibly cryomagma-inflated 'hot cross bun' feature and anomalous midlatitude ridges that may be paleodunes from a different climate epoch. The accumulating body of topographic data from altimetry and SARtopo has permitted the assembly of a global topographic map (albeit substantially interpolated) and an estimate of the spherical harmonic shape out to degree ~12. These datasets will be of substantial value in interpreting Titan's structure and geology, and as a boundary condition on global circulation models and fluvial studies. The growing number of overlap regions also permits stereo topography on smaller scales (e.g. of impact structures Ksa and Soi) which helps to understand the processes obliterating craters on Titan.

  16. Saturn's aurora observed by the Cassini camera at visible wavelengths

    Science.gov (United States)

    Dyudina, Ulyana A.; Ingersoll, Andrew P.; Ewald, Shawn P.; Wellington, Danika

    2016-01-01

    The first observations of Saturn's visible-wavelength aurora were made by the Cassini camera. The aurora was observed between 2006 and 2013 in the northern and southern hemispheres. The color of the aurora changes from pink at a few hundred km above the horizon to purple at 1000-1500 km above the horizon. The spectrum observed in 9 filters spanning wavelengths from 250 nm to 1000 nm has a prominent H-alpha line and roughly agrees with laboratory simulated auroras. Auroras in both hemispheres vary dramatically with longitude. Auroras form bright arcs between 70° and 80° latitude north and between 65° and 80° latitude south, which sometimes spiral around the pole, and sometimes form double arcs. A large 10,000-km-scale longitudinal brightness structure persists for more than 100 h. This structure rotates approximately together with Saturn. On top of the large steady structure, the auroras brighten suddenly on the timescales of a few minutes. These brightenings repeat with a period of ∼1 h. Smaller, 1000-km-scale structures may move faster or lag behind Saturn's rotation on timescales of tens of minutes. The persistence of nearly-corotating large bright longitudinal structure in the auroral oval seen in two movies spanning 8 and 11 rotations gives an estimate on the period of 10.65 ± 0.15 h for 2009 in the northern oval and 10.8 ± 0.1 h for 2012 in the southern oval. The 2009 north aurora period is close to the north branch of Saturn Kilometric Radiation (SKR) detected at that time.

  17. Saturn's Aurora Observed by Cassini Camera in Visible Wavelengths

    Science.gov (United States)

    Dyudina, U.; Ingersoll, A. P.; Ewald, S.; Wellington, D. F.

    2014-12-01

    Cassini camera's movies in 2009-2013 show Saturn's aurora in both the northern and southern hemispheres. The color of the aurora changes from pink at a few hundreds of km above the cloud tops to purple at 1000-1500 km above the cloud tops. The spectrum observed in 9 lters spanning wavelengths from 250 nm to 1000 nm has a prominent H-alpha line and roughly agrees with the laboratory simulated auroras [1]. Auroras in both hemispheres vary dramatically with longitude. Auroras form bright arcs, sometimes a spiral around the pole, and sometimes double arcs at 70-75 both north and south latitude. 10,000-km-scale longitudinal brightness structures can persist for more than 100 hours. This structures rotate together with Saturn. Besides the steady structure, the auroras brighten suddenly on the timescales of few minutes. 1000-km-scale disturbances may move faster or lag behind Saturn's rotation on timescales of tens of minutes. The persistence of the longitudinal structure of the aurora in two long observations in 2009 and 2012 allowed us to estimate its period of rotation of 10.65±0.15 h for 2009 and 10.8±0.1 h for 2012. The 2009 north aurora period is close to the north branch of Saturn Kilometric Radiation (SKR) detected at that time. The 2012 south aurora period is longer than the SKR periods detected at the time. These periods are also close to the rotation period of the lightning storms on Saturn. We discuss those periodicities and their relevance to Saturn's internal rotation. [1] Aguilar, A. et al. The Electron-Excited Mid-Ultraviolet to Near-Infrared Spectrum of H2:Cross Sections and Transition Probabilities. Astrophys. J. Supp. Ser. 177, 388-407 (2008).

  18. New constraints on Saturn's interior from Cassini astrometric data

    Science.gov (United States)

    Lainey, Valéry; Jacobson, Robert A.; Tajeddine, Radwan; Cooper, Nicholas J.; Murray, Carl; Robert, Vincent; Tobie, Gabriel; Guillot, Tristan; Mathis, Stéphane; Remus, Françoise; Desmars, Josselin; Arlot, Jean-Eudes; De Cuyper, Jean-Pierre; Dehant, Véronique; Pascu, Dan; Thuillot, William; Le Poncin-Lafitte, Christophe; Zahn, Jean-Paul

    2017-01-01

    Using astrometric observations spanning more than a century and including a large set of Cassini data, we determine Saturn's tidal parameters through their current effects on the orbits of the eight main and four coorbital Moons. We have used the latter to make the first determination of Saturn's Love number from observations, k2=0.390 ± 0.024, a value larger than the commonly used theoretical value of 0.341 (Gavrilov & Zharkov, 1977), but compatible with more recent models (Helled & Guillot, 2013) for which the static k2 ranges from 0.355 to 0.382. Depending on the assumed spin for Saturn's interior, the new constraint can lead to a significant reduction in the number of potential models, offering great opportunities to probe the planet's interior. In addition, significant tidal dissipation within Saturn is confirmed (Lainey et al., 2012) corresponding to a high present-day tidal ratio k2/Q=(1.59 ± 0.74) × 10-4 and implying fast orbital expansions of the Moons. This high dissipation, with no obvious variations for tidal frequencies corresponding to those of Enceladus and Dione, may be explained by viscous friction in a solid core, implying a core viscosity typically ranging between 1014 and 1016 Pa.s (Remus et al., 2012). However, a dissipation increase by one order of magnitude at Rhea's frequency could suggest the existence of an additional, frequency-dependent, dissipation process, possibly from turbulent friction acting on tidal waves in the fluid envelope of Saturn (Ogilvie & Lin, 2004; Fuller et al. 2016).

  19. Cassini Attitude and Articulation Control Subsystem Fault Protection Challenges During Saturn Proximal Orbits

    Science.gov (United States)

    Bates, David M.

    2015-01-01

    NASA's Cassini Spacecraft, launched on October 15th, 1997 arrived at Saturn on June 30th, 2004, is the largest and most ambitious interplanetary spacecraft in history. As the first spacecraft to achieve orbit at Saturn, Cassini has collected science data throughout its four-year prime mission (2004-08), and has since been approved for a first and second extended mission through 2017. As part of the final extended mission, Cassini will begin an aggressive and exciting campaign of high inclination low altitude flybys within the inner most rings of Saturn, skimming Saturn's outer atmosphere, until the spacecraft is finally disposed of via planned impact with the planet. This final campaign, known as the proximal orbits, presents unique fault protection related challenges, the details of which are discussed in this paper.

  20. Cassini's Maneuver Automation Software (MAS) Process: How to Successfully Command 200 Navigation Maneuvers

    Science.gov (United States)

    Yang, Genevie Velarde; Mohr, David; Kirby, Charles E.

    2008-01-01

    To keep Cassini on its complex trajectory, more than 200 orbit trim maneuvers (OTMs) have been planned from July 2004 to July 2010. With only a few days between many of these OTMs, the operations process of planning and executing the necessary commands had to be automated. The resulting Maneuver Automation Software (MAS) process minimizes the workforce required for, and maximizes the efficiency of, the maneuver design and uplink activities. The MAS process is a well-organized and logically constructed interface between Cassini's Navigation (NAV), Spacecraft Operations (SCO), and Ground Software teams. Upon delivery of an orbit determination (OD) from NAV, the MAS process can generate a maneuver design and all related uplink and verification products within 30 minutes. To date, all 112 OTMs executed by the Cassini spacecraft have been successful. MAS was even used to successfully design and execute a maneuver while the spacecraft was in safe mode.

  1. The Double Flybys of the Cassini Mission: Navigation Challenges and Lessons Learned

    Science.gov (United States)

    Wagner, Sean; Buffington, Brent

    2014-01-01

    Since 2004, the Cassini spacecraft has flown by Titan and other Saturn moons numerous times, successfully accomplishing its 100th targeted encounter of Titan in March 2014. The navigation of Cassini is challenging, even more so with "double flybys," two encounters separated by at most a few days. Because of this tight spacing, there is not enough time for a maneuver in between. Additionally, maneuvers prior to a double flyby only target one of the two encounters. This paper discusses the challenges faced by the Cassini Navigation Team with each double flyby, as well as lessons learned during operational support of each dual encounter. The strengths and weaknesses of the targeting strategies considered for each double flyby are also detailed, by comparing downstream ?V costs and changes to the non-targeted flyby conditions.

  2. Cassini Operational Sun Sensor Risk Management During Proximal Orbit Saturn Ring Plane Crossings

    Science.gov (United States)

    Bates, David M.

    2016-01-01

    NASA's Cassini Spacecraft, launched on October 15th, 1997 which arrived at Saturn on June 30th, 2004, is the largest and most ambitious interplanetary spacecraft in history. As the first spacecraft to achieve orbit at Saturn, Cassini has collected science data throughout its four-year prime mission (2004–08), and has since been approved for a first and second extended mission through 2017. As part of the final extended missions, Cassini will begin an aggressive and exciting campaign of high inclination, low altitude flybys within the inner most rings of Saturn, skimming Saturn’s outer atmosphere, until the spacecraft is finally disposed of via planned impact with the planet. This final campaign, known as the proximal orbits, requires a strategy for managing the Sun Sensor Assembly (SSA) health, the details of which are presented in this paper.

  3. Cassini Attitude and Articulation Control Subsystem Fault Protection Challenges During Saturn Proximal Orbits

    Science.gov (United States)

    Bates, David M.

    2015-01-01

    NASA's Cassini Spacecraft, launched on October 15th, 1997 arrived at Saturn on June 30th, 2004, is the largest and most ambitious interplanetary spacecraft in history. As the first spacecraft to achieve orbit at Saturn, Cassini has collected science data throughout its four-year prime mission (2004-08), and has since been approved for a first and second extended mission through 2017. As part of the final extended mission, Cassini will begin an aggressive and exciting campaign of high inclination low altitude flybys within the inner most rings of Saturn, skimming Saturn's outer atmosphere, until the spacecraft is finally disposed of via planned impact with the planet. This final campaign, known as the proximal orbits, presents unique fault protection related challenges, the details of which are discussed in this paper.

  4. Cassini's Maneuver Automation Software (MAS) Process: How to Successfully Command 200 Navigation Maneuvers

    Science.gov (United States)

    Yang, Genevie Velarde; Mohr, David; Kirby, Charles E.

    2008-01-01

    To keep Cassini on its complex trajectory, more than 200 orbit trim maneuvers (OTMs) have been planned from July 2004 to July 2010. With only a few days between many of these OTMs, the operations process of planning and executing the necessary commands had to be automated. The resulting Maneuver Automation Software (MAS) process minimizes the workforce required for, and maximizes the efficiency of, the maneuver design and uplink activities. The MAS process is a well-organized and logically constructed interface between Cassini's Navigation (NAV), Spacecraft Operations (SCO), and Ground Software teams. Upon delivery of an orbit determination (OD) from NAV, the MAS process can generate a maneuver design and all related uplink and verification products within 30 minutes. To date, all 112 OTMs executed by the Cassini spacecraft have been successful. MAS was even used to successfully design and execute a maneuver while the spacecraft was in safe mode.

  5. Discovering habitable environments and life in the Saturn System (Jean Dominique Cassini Medal Lecture)

    Science.gov (United States)

    Lunine, Jonathan I.

    2015-04-01

    One of the most notable scientific adventures of our time is being conducted jointly by Europe and the United States around the solar system's great ringed planet, Saturn. The Cassini-Huygens mission arrived in orbit in 2004, and the Huygens probe descended through Titan's atmosphere in January 2005. Titan's surface has been found to host a rich and still-enigmatic methane cycle, complete with lakes, seas, rivers and rain. Enceladus is jetting its interior volatiles into space, where the Cassini Orbiter detected and measured a number of species within the resulting plume. These include water, organic molecules, nitrogen compounds, and salts. Cassini radio science detected the presence within both Enceladus and Titan of internal water oceans. Variability with orbital phase of the Enceladus plume, also discovered by the Cassini Orbiter, makes a convincing case for the jets themselves being derived from the deep interior and controlled by tidal forces. Both Enceladus and Titan host potentially habitable environments, and they represent unique opportunities for testing whether either or both of these bodies harbor life. Titan's interior will be difficult to access, but its large surface hydrocarbon seas can be explored in situ with Huygens-like vehicles. The Cassini Orbiter determined the liquid in Titan's seas to be methane and ethane, which raises the question of whether simple chemistry can evolve into autocatalysis and self-replication in a non-aqueous liquid environment. In effect, is there an exotic kind of "life" in the Titan seas? Enceladus is perhaps more straightforward: given that the interior water ocean as expressed through the plume appears to satisfy the formal requirements for habitability, is biological activity occurring there? Answering these questions will require a new generation of robotic vehicles beyond Cassini-Huygens -- and new opportunities for international collaborations in planetary exploration.

  6. The Orbits of Saturn's Small Satellites Derived from Combined Historic and Cassini Imaging Observations

    Science.gov (United States)

    Spitale, J. N.; Jacobson, R. A.; Porco, C. C.; Owen, W. M., Jr.

    2006-08-01

    We report on the orbits of the small, inner Saturnian satellites, either recovered or newly discovered in recent Cassini imaging observations. The orbits presented here reflect improvements over our previously published values in that the time base of Cassini observations has been extended, and numerical orbital integrations have been performed in those cases in which simple precessing elliptical, inclined orbit solutions were found to be inadequate. Using combined Cassini and Voyager observations, we obtain an eccentricity for Pan 7 times smaller than previously reported because of the predominance of higher quality Cassini data in the fit. The orbit of the small satellite (S/2005 S1 [Daphnis]) discovered by Cassini in the Keeler gap in the outer A ring appears to be circular and coplanar; no external perturbations are apparent. Refined orbits of Atlas, Prometheus, Pandora, Janus, and Epimetheus are based on Cassini , Voyager, Hubble Space Telescope, and Earth-based data and a numerical integration perturbed by all the massive satellites and each other. Atlas is significantly perturbed by Prometheus, and to a lesser extent by Pandora, through high-wavenumber mean-motion resonances. Orbital integrations involving Atlas yield a mass of GMAtlas=(0.44+/-0.04)×10-3 km3 s -2, 3 times larger than reported previously (GM is the product of the Newtonian constant of gravitation G and the satellite mass M). Orbital integrations show that Methone is perturbed by Mimas, Pallene is perturbed by Enceladus, and Polydeuces librates around Dione's L5 point with a period of about 791 days. We report on the nature and orbits of bodies sighted in the F ring, two of which may have persisted for a year or more.

  7. Cassini Dust Measurements at Enceladus and Implications for the Origin of the E Ring

    Science.gov (United States)

    Spahn, Frank; Schmidt, Jürgen; Albers, Nicole; Hörning, Marcel; Makuch, Martin; Seiß, Martin; Kempf, Sascha; Srama, Ralf; Dikarev, Valeri; Helfert, Stefan; Moragas-Klostermeyer, Georg; Krivov, Alexander V.; Sremčević, Miodrag; Tuzzolino, Anthony J.; Economou, Thanasis; Grün, Eberhard

    2006-03-01

    During Cassini's close flyby of Enceladus on 14 July 2005, the High Rate Detector of the Cosmic Dust Analyzer registered micron-sized dust particles enveloping this satellite. The dust impact rate peaked about 1 minute before the closest approach of the spacecraft to the moon. This asymmetric signature is consistent with a locally enhanced dust production in the south polar region of Enceladus. Other Cassini experiments revealed evidence for geophysical activities near Enceladus' south pole: a high surface temperature and a release of water gas. Production or release of dust particles related to these processes may provide the dominant source of Saturn's E ring.

  8. VIMS spectral mapping observations of Titan during the Cassini prime mission

    Science.gov (United States)

    Barnes, J.W.; Soderblom, J.M.; Brown, R.H.; Buratti, B.J.; Sotin, Christophe; Baines, K.H.; Clark, R.N.; Jaumann, R.; McCord, T.B.; Nelson, R.; Le, Mouelic S.; Rodriguez, S.; Griffith, C.; Penteado, P.; Tosi, F.; Pitman, K.M.; Soderblom, L.; Stephan, K.; Hayne, P.; Vixie, G.; Bibring, J.-P.; Bellucci, G.; Capaccioni, F.; Cerroni, P.; Coradini, A.; Cruikshank, D.P.; Drossart, P.; Formisano, V.; Langevin, Y.; Matson, D.L.; Nicholson, P.D.; Sicardy, B.

    2009-01-01

    This is a data paper designed to facilitate the use of and comparisons to Cassini/visual and infrared mapping spectrometer (VIMS) spectral mapping data of Saturn's moon Titan. We present thumbnail orthographic projections of flyby mosaics from each Titan encounter during the Cassini prime mission, 2004 July 1 through 2008 June 30. For each flyby we also describe the encounter geometry, and we discuss the studies that have previously been published using the VIMS dataset. The resulting compliation of metadata provides a complementary big-picture overview of the VIMS data in the public archive, and should be a useful reference for future Titan studies. ?? 2009 Elsevier Ltd.

  9. Constraints on MOND theory from radio tracking data of the Cassini spacecraft

    CERN Document Server

    Hees, A; Jacobson, R A; Park, R S

    2014-01-01

    The MOdified Newtonian Dynamics (MOND) is an attempt to modify the gravitation theory to solve the Dark Matter problem. This phenomenology is very successful at the galactic level. The main effect produced by MOND in the Solar System is called the External Field Effect parametrized by the parameter $Q_2$. We have used 9 years of Cassini range and Doppler measurements to constrain $Q_2$. Our estimate of this parameter based on Cassini data is given by $Q_2=(3 \\pm 3)\\times 10^{-27} \\ \\rm{s^{-2}}$ which shows no deviation from General Relativity and excludes a large part of the relativistic MOND theories.

  10. Twenty Years of Systems Engineering on the Cassini-Huygens Mission

    Science.gov (United States)

    Manor-Chapman, Emily

    2013-01-01

    Over the past twenty years, the Cassini-Huygens Mission has successfully utilized systems engineering to develop and execute a challenging prime mission and two mission extensions. Systems engineering was not only essential in designing the mission, but as knowledge of the system was gained during cruise and science operations, it was critical in evolving operational strategies and processes. This paper discusses systems engineering successes, challenges, and lessons learned on the Cassini-Huygens Mission gathered from a thorough study of mission plans and developed scenarios, and interviews with key project leaders across its twenty-year history.

  11. Temperature Variations of Saturn Rings with Viewing Geometries from Prime to Equinox Cassini Missions

    Science.gov (United States)

    Deau, E. A.; Spilker, L. J.; Morishima, R.; Brooks, S.; Pilorz, S.; Altobelli, N.

    2011-01-01

    After more than six years in orbit around Saturn, the Cassini Composite Infrared Spectrometer (CIRS) has acquired an extensive set of measurements of Saturn's main rings (A, B, C and Cassini Division) in the thermal infrared. Temperatures were retrieved for the lit and unlit rings over a variety of ring geometries that include phase angle, solar and spacecraft elevations and local time. We show that some of these parameters (solar and spacecraft elevations, phase angle) play a role in the temperature variations in the first order, while the others (ring and particle local time) produced second order effects. The results of this comparison will be presented.

  12. Classification of conics and Cassini curves in Minkowski space-time plane

    Directory of Open Access Journals (Sweden)

    Emad N. Shonoda

    2016-04-01

    Full Text Available In this paper we use the Apollonius definition of conics to generate algebraic curves in the Minkowski space-time plane M2, which turn out to be different from classical conic sections. We extend and classify this sort of “M-conics”. We discuss the cases of the singularity points of these M-conics, coming from the transition from timelike world to spacelike world through the lightlike one. Finally, we translate the classical concept of Cassini curves with two foci and that of (multifocal Cassini curves to Minkowski planes M2.

  13. Cassini Attitude Control Flight Software: from Development to In-Flight Operation

    Science.gov (United States)

    Brown, Jay

    2008-01-01

    The Cassini Attitude and Articulation Control Subsystem (AACS) Flight Software (FSW) has achieved its intended design goals by successfully guiding and controlling the Cassini-Huygens planetary mission to Saturn and its moons. This paper describes an overview of AACS FSW details from early design, development, implementation, and test to its fruition of operating and maintaining spacecraft control over an eleven year prime mission. Starting from phases of FSW development, topics expand to FSW development methodology, achievements utilizing in-flight autonomy, and summarize lessons learned during flight operations which can be useful to FSW in current and future spacecraft missions.

  14. Cassini Attitude Control Flight Software: from Development to In-Flight Operation

    Science.gov (United States)

    Brown, Jay

    2008-01-01

    The Cassini Attitude and Articulation Control Subsystem (AACS) Flight Software (FSW) has achieved its intended design goals by successfully guiding and controlling the Cassini-Huygens planetary mission to Saturn and its moons. This paper describes an overview of AACS FSW details from early design, development, implementation, and test to its fruition of operating and maintaining spacecraft control over an eleven year prime mission. Starting from phases of FSW development, topics expand to FSW development methodology, achievements utilizing in-flight autonomy, and summarize lessons learned during flight operations which can be useful to FSW in current and future spacecraft missions.

  15. An INCA model for pathogens in rivers and catchments: Model structure, sensitivity analysis and application to the River Thames catchment, UK.

    Science.gov (United States)

    Whitehead, P G; Leckie, H; Rankinen, K; Butterfield, D; Futter, M N; Bussi, G

    2016-12-01

    Pathogens are an ongoing issue for catchment water management and quantifying their transport, loss and potential impacts at key locations, such as water abstractions for public supply and bathing sites, is an important aspect of catchment and coastal management. The Integrated Catchment Model (INCA) has been adapted to model the sources and sinks of pathogens and to capture the dominant dynamics and processes controlling pathogens in catchments. The model simulates the stores of pathogens in soils, sediments, rivers and groundwaters and can account for diffuse inputs of pathogens from agriculture, urban areas or atmospheric deposition. The model also allows for point source discharges from intensive livestock units or from sewage treatment works or any industrial input to river systems. Model equations are presented and the new pathogens model has been applied to the River Thames in order to assess total coliform (TC) responses under current and projected future land use. A Monte Carlo sensitivity analysis indicates that the input coliform estimates from agricultural sources and decay rates are the crucial parameters controlling pathogen behaviour. Whilst there are a number of uncertainties associated with the model that should be accounted for, INCA-Pathogens potentially provides a useful tool to inform policy decisions and manage pathogen loading in river systems. Copyright © 2016. Published by Elsevier B.V.

  16. Simulating dissolved organic carbon dynamics at the swedish integrated monitoring sites with the integrated catchments model for carbon, INCA-C.

    Science.gov (United States)

    Futter, M N; Löfgren, S; Köhler, S J; Lundin, L; Moldan, F; Bringmark, L

    2011-12-01

    Surface water concentrations of dissolved organic carbon ([DOC]) are changing throughout the northern hemisphere due to changes in climate, land use and acid deposition. However, the relative importance of these drivers is unclear. Here, we use the Integrated Catchments model for Carbon (INCA-C) to simulate long-term (1996-2008) streamwater [DOC] at the four Swedish integrated monitoring (IM) sites. These are unmanaged headwater catchments with old-growth forests and no major changes in land use. Daily, seasonal and long-term variations in streamwater [DOC] driven by runoff, seasonal temperature and atmospheric sulfate (SO₄(2-)) deposition were observed at all sites. Using INCA-C, it was possible to reproduce observed patterns of variability in streamwater [DOC] at the four IM sites. Runoff was found to be the main short-term control on [DOC]. Seasonal patterns in [DOC] were controlled primarily by soil temperature. Measured SO₄(2-) deposition explained some of the long-term [DOC] variability at all sites.

  17. The Making of the Hero in the Land of the Cinnamon Tree: Gonzalo Pizarro in the Royal Commentaries of Garcilaso Inca

    Directory of Open Access Journals (Sweden)

    Carmela Zanelli Velásquez

    2014-11-01

    Full Text Available Prior to his rebellion against the Spanish Crown in 1544, Gonzalo Pizarro (Francisco’s younger brother accomplished the Conquest of Charcas (present-day northwestern Bolivia, survived the siege of Cuzco by Manco Inca and attempted the failed exploration of the mythical «Land of the Cinnamon Tree», located somewhere in the Amazonian basin, according to Garcilaso’s historical account. During this doomed expedition, Pizarro endured treason, lost companions and was defeated by the forces of an aggressive environment. However, he ma­naged to emerge as the legendary political and military leader that rebelled against the first Viceroy of Peru, Blasco Nuñez Vela in 1546. Nuñez Vela would be defeated in battlefield and later executed. Gonzalo Pizarro’s pretension of becoming king of Peru by virtue of a political alliance with the surviving Incas would be seen in Garcilaso’s account as a proof of Pizarro’s heroic stature, albeit a tragic one.

  18. Cassini's Ring Grazing and Grand Finale Orbits: Topping Off an Awesome Mission

    Science.gov (United States)

    Edgington, Scott; Spilker, Linda; Coustenis, Athena

    2017-04-01

    The Cassini-Huygens mission, a joint collaboration between NASA, ESA, and the Italian Space Agency, is in its last year of operations after nearly 13 years in orbit around Saturn. Cassini will send back its final bits of unique data on September 15th, 2017 as it plunges into Saturn's atmosphere, vaporizing and satisfying planetary protection requirements. Before that time Cassini will continue its legacy of exploration and discovery in 2017 and return unique science data provided by orbits taking the spacecraft into unexplored regions near Saturn and its rings. From the new vantage points, Cassini will continue to study seasonal and temporal changes in the system as northern summer solstice approaches. With the exception of one remaining targeted Titan flyby, all of Cassini's close icy satellite flybys, including those of Enceladus, are now completed. In November 2016, Cassini transitioned to a series of orbits with peripases just outside Saturn's F ring. These 20 orbits include close flybys of some tiny ring moons and excellent views of the F ring and Saturn's outer A ring. The 126th and final close flyby of Titan will propel Cassini across Saturn's main rings and into its Grand Finale series of orbits. Cassini's Grand Finale, starting in April 2017, is comprised of 22 orbits at an inclination of 63 degrees. Cassini will repeatedly dive between Saturn's innermost rings and upper atmosphere providing insights into fundamental questions unattainable during the rest of the mission. Cassini will be the first spacecraft to explore this region. These close orbits provide the highest resolution observations of both the rings and Saturn, and direct in-situ sampling of the ring particles, composition, plasma, Saturn's exosphere and the innermost radiation belts. Saturn's gravitational field will be measured to unprecedented accuracy, providing information on the interior structure of the planet, winds in the outer layers of Saturn's atmosphere, and the mass distribution in

  19. Cassini results on Titan's atmospheric and surface properties changes since the northern equinox

    Science.gov (United States)

    Coustenis, Athena; Drossart, Pierre; Flasar, F. Michael; Achterberg, Richard K.; Rodriguez, Sebastien; Nixon, Conor; Bampasidis, Georgios; Solomonidou, Anezina; Jennings, Donald; Lavvas, Panayiotis

    2016-07-01

    -term variations both in the atmosphere and the surface and the two environments are connected. Deposits from the atmosphere can be found on the ground and the tropospheric processes (clouds, rain) affect the appearance of the surface. Thus, we analyse spectro-imaging data (0.8-5.2 µm) from Cassini/VIMS to study Titan's surface multivariable geological terrain and its interactions with the lower atmosphere. The Cassini's Visual and Infrared Mapping Spectrometer (VIMS) and other instruments have provided a better understanding of the dynamic and complex surface expressions of this Saturnian moon, suggesting exogenic and endogenic processes [3;4;5].We apply a Radiative transfer code to analyse different regions and to monitor their spectral behavior with time [6;7,8]. We have already shown that temporal variations of surface albedo (in chemical composition and/or morphology) exist for some areas, but that their origin may differ from one region to the other. Tui Regio and Sotra Patera for instance change with time becoming darker and brighter respectively in terms of surface albedo while the undifferentiated plains and the suggested evaporitic areas in the equatorial regions do not present any significant change [8]. We will infer information on the haze content that we will compare with findings from the stratosphere by CIRS and we will compare with cloud monitoring over specific regions [9]. It remains to identify the role the atmosphere plays in the surface changes. References: [1] Coustenis, et al., Icarus 207, 461, 2010 ; Astrophys. J. 799, 177, 9p ; Icarus, in press, 2015 ; [2] Jennings et al., ApJ 804, L34, 5, 2015; [3] Lopes, R.M.C., et al.: JGR, 118, 416-435, 2013 ; [4] Solomonidou, A., et al.: PSS, 70, 77-104, 2013 ; [5] Moore, J.M., and Howard, A.D.: GRL, 37, L22205, 2010; [6] Hirtzig, M., et al.: Icarus, 226, 470-486, 2013 ; [7] Solomonidou, A., et al.: JGR, 119, 1729-1747, 2014; [8] Solomonidou, A., et al.: Icarus, in press, 2015; [9] Rodriguez et al., Icarus 216, 89

  20. Temporal variations of Titan's surface with Cassini/VIMS

    Science.gov (United States)

    Solomonidou, Anezina; Coustenis, A.; Hirtzig, M.; Rodriguez, S.; Stephan, K.; Lopes, R. M. C.; Drossart, P.; Sotin, C.; Le Mouélic, S.; Lawrence, K.; Bratsolis, E.; Jaumann, R.; Brown, R. H.

    2016-05-01

    We analyze Cassini VIMS data of several areas on Titan's surface looking for variations with time. Three of these locations are near the equator (10-30°S), namely Hotei Regio, Tui Regio and Sotra Patera; in some cases changes in brightness and/or in appearance were reported therein. We also investigate a portion of the undifferentiated plains, areas relatively homogeneous and dark in radar observations, located near 20-25°N. This is a follow-up on a previous paper in which we had inferred surface albedos for some distinct regions of interest (RoIs) identified within the Hotei, Tui and Sotra areas through a Principal Component Analysis (PCA) and radiative transfer (RT) modeling (Solomonidou [2014]. J. Geophys. Res. 119, 1729-1747). We apply the same methods here to a larger dataset looking for variations of the surface albedo with time and using the Huygens landing site as the 'ground truth' for calibration purposes. As expected, the undifferentiated plains remain unchanged from January 2010 to June 2012. Our analysis of Hotei Regio data from March 2005 to March 2009 also does not show any significant surface albedo variations within uncertainties. We note however that our RT retrievals are not optimal in this case because of the use of a plane-parallel code and the unfavorable geometry of the associated datasets. Conversely, Tui Regio and Sotra Patera show surface albedo fluctuations with time with pronounced trends for darkening and for brightening respectively. The Tui Regio spectrum exhibits a surface albedo decrease from March 2005 to February 2009, at 0.94, 1.08, 2.03, and 5 μm wavelengths, while the spectrum shape remains the same over that time. On the contrary, the Sotra Patera area became at least two times brighter within a year (April 2005-February 2006), at 1.58 μm, 2.03 μm, and 5 μm. We also retrieved surface albedo spectra for three reference regions surrounding Hotei, Tui and Sotra and for three additional regions we use as 'test cases' that

  1. Constraints on Saturn's Tropospheric General Circulation from Cassini ISS Images

    Science.gov (United States)

    DelGenio, Anthony D.; Barbara, John M.

    2013-01-01

    An automated cloud tracking algorithm is applied to Cassini Imaging Science Subsystem high-resolution apoapsis images of Saturn from 2005 and 2007 and moderate resolution images from 2011 and 2012 to define the near-global distribution of zonal winds and eddy momentum fluxes at the middle troposphere cloud level and in the upper troposphere haze. Improvements in the tracking algorithm combined with the greater feature contrast in the northern hemisphere during the approach to spring equinox allow for better rejection of erroneous wind vectors, a more objective assessment at any latitude of the quality of the mean zonal wind, and a population of winds comparable in size to that available for the much higher contrast atmosphere of Jupiter. Zonal winds at cloud level changed little between 2005 and 2007 at all latitudes sampled. Upper troposphere zonal winds derived from methane band images are approx. 10 m/s weaker than cloud level winds in the cores of eastward jets and approx. 5 m/s stronger on either side of the jet core, i.e., eastward jets appear to broaden with increasing altitude. In westward jet regions winds are approximately the same at both altitudes. Lateral eddy momentum fluxes are directed into eastward jet cores, including the strong equatorial jet, and away from westward jet cores and weaken with increasing altitude on the flanks of the eastward jets, consistent with the upward broadening of these jets. The conversion rate of eddy to mean zonal kinetic energy at the visible cloud level is larger in eastward jet regions (5.2x10(exp -5) sq m/s) and smaller in westward jet regions (1.6x10(exp -5) sqm/s) than the global mean value (4.1x10(ep -5) sq m/s). Overall the results are consistent with theories that suggest that the jets and the overturning meridional circulation at cloud level on Saturn are maintained at least in part by eddies due to instabilities of the large-scale flow near and/or below the cloud level.

  2. Icy Satellite Science Today and in Cassini's Final Three Years

    Science.gov (United States)

    Buratti, B. J.

    2014-12-01

    The Cassini Mission has turned our view of Saturn's icy moons from scientific sketches to fully realized worlds. Among the major discoveries are: Activity on Enceladus and associated plumes that originate in small hot spots on its south pole and that appear to be modulated by tidal forces; a liquid subsurface water ocean on Enceladus that is a habitable environment; several new moons; debris rings associated with moons; a unique equatorial ridge on Iapetus; the identity of new constituents on the moons including carbon dioxide ice on most of them and polycyclic aromatic hydrocarbons (PAHs)on Iapetus; differentiated or partially differentiated interiors; nano-iron on the surfaces of the moons and in the rings; volatile segregation on Iapetus and Hyperion; and a bewildering array of geologic processes on the small moons. But our new view of these icy worlds has spawned new questions. Among these unanswered questions are: How variable are the plumes? Have any other moons had activity similar to that on Enceladus and did it continue up to the recent past? How much dust do the moons contribute to the region around Saturn? What caused the ridge on Iapetus? What are the interiors of the moons like? How differentiated and compensated are they? Five additional targeted flybys, two of Dione and three of Enceladus, have been designed to answer these questions and will be implemented during the remainder of the Solstice Mission. The Dione flybys both include gravity passes to determine its state of differentiation. One of the flybys is optimized to measure the fields and particle environment around Dione. One of the two remote-sensing flybys of Enceladus will scrutinize the south polar region to further understand the size, temperature, and variability of the emitting areas, while the other will observe the north pole to determine why it is so different from the south. The third Enceladus flyby involves an unprecedented pass less than 50 km above the surface into the midst of

  3. Methane Band and Continuum Band Imaging of Titan's Atmosphere Using Cassini ISS Narrow Angle Camera Pictures from the CURE/Cassini Imaging Project

    Science.gov (United States)

    Shitanishi, Jennifer; Gillam, S. D.

    2009-05-01

    The study of Titan's atmosphere, which bears resemblance to early Earth's, may help us understand more of our own. Constructing a Monte Carlo model of Titan's atmosphere is helpful to achieve this goal. Methane (MT) and continuum band (CB) images of Titan taken by the CURE/Cassini Imaging Project, using the Cassini Narrow Angle Camera (NAC) were analyzed. They were scheduled by Cassini Optical Navigation. Images were obtained at phase 53°, 112°, 161°, and 165°. They include 22 total MT1(center wavelength at 619nm), MT2(727nm), MT3(889nm), CB1(635nm), CB2(751nm), and CB3(938nm) images. They were reduced with previously written scripts using the National Optical Astronomy Observatory Image Reduction and Analysis Facility scientific analysis suite. Correction for horizontal and vertical banding and cosmic ray hits were made. The MT images were registered with corresponding CB images to ensure that subsequently measured fluxes ratios came from the same parts of the atmosphere. Preliminary DN limb-to-limb scans and loci of the haze layers will be presented. Accurate estimates of the sub-spacecraft points on each picture will be presented. Flux ratios (FMT/FCB=Q0) along the scans and total absorption coefficients along the lines of sight from the spacecraft through the pixels (and into Titan) will also be presented.

  4. Esofagectomia trans-hiatal versus transtorácica: experiência do Instituto Nacional do Câncer (INCA

    Directory of Open Access Journals (Sweden)

    Emerson Luis Gama Prisco

    Full Text Available OBJETIVO: Analisar comparativamente a morbimortalidade e sobrevida após esofagectomia trans-hiatal (TH ou transtorácica (TT. METODOS: Estudo retrospectivo não randomizado de 68 pacientes com neoplasia de esôfago operados no INCA entre 1997 e 2005, divididos em dois grupos: 1 - TH (33 pacientes; e 2 - TT (35 pacientes. RESULTADOS: A idade média foi 40,7 anos (25 - 74 anos, sendo 73,5% homens. Tumores do 1/3 médio predominaram no Grupo 2 (48,6% versus 21,2%, p = 0,02. A média de linfonodos dissecados foi maior no Grupo 2 (21,6 versus 17,8 linfonodos, p = 0,04, porém sem diferença no número de linfonodos metastáticos (4,1 versus 3,9 linfonodos, p = 0,85. O tempo cirúrgico médio foi maior no Grupo 2 (410 versus 270 minutos, p = 0,001. O tempo médio de internação também foi maior no Grupo 2 (19 versus 14 dias, p = 0,001. A morbidade operatória foi 50%, sem diferença significativa (42,4% versus 57,1%, p = 0,23. Fístula esofágica ocorreu em 13,2%, sem diferença significativa (9,1% versus 17,1%, p = 0,23. A mortalidade foi 5,8% (04 pacientes, sem diferença significativa (1,4% versus 4,4%, p = 0,83. CONCLUSÃO: Neste estudo, a morbimortalidade não apresentou diferença em relação à via de acesso para a esofagectomia, apesar do maior tempo cirúrgico e de permanência hospitalar na via TT. A sobrevida global em 3 e 5 anos também foi maior na TT, possivelmente devido a maior freqüência de estágios iniciais em pacientes submetidos à transtorácica.

  5. Alignment and Polarization Sensitivity Study for the Cassini-Composite InfraRed Spectrometer (CIRS) Far InfraRed (FIR) Interferometer

    Science.gov (United States)

    Crooke, Julie A.; Hagopian, John G.

    1998-01-01

    The Composite InfraRed Spectrometer (CIRS) instrument flying on the Cassini spacecraft to Saturn is a cryogenic spectrometer with far-infrared (FIR) and mid-infrared (MIR) channels. The CIRS FIR channel is a polarizing interferometer that contains three polarizing grid components. These components are an input polarizer, a polarizing beamsplitter, and an output polarizer/analyzer. They consist of a 1.5 micron thick mylar substrate with 2 gm wide copper wires, with 2 gm spacing (4 micron pitch) photolithographically deposited on the substrate. This paper details the polarization sensitivity studies performed on the output polarizer/analyzer, and the alignment sensitivity studies performed on the input polarizer and beamsplitter components in the FIR interferometer.

  6. Titan's surface at 2.2-cm wavelength imaged by the Cassini RADAR radiometer: Calibration and first results

    Science.gov (United States)

    Janssen, M.A.; Lorenz, R.D.; West, R.; Paganelli, F.; Lopes, R.M.; Kirk, R.L.; Elachi, C.; Wall, S.D.; Johnson, W.T.K.; Anderson, Y.; Boehmer, R.A.; Callahan, P.; Gim, Y.; Hamilton, G.A.; Kelleher, K.D.; Roth, L.; Stiles, B.; Le, Gall A.

    2009-01-01

    The first comprehensive calibration and mapping of the thermal microwave emission from Titan's surface is reported based on radiometric data obtained at 2.2-cm wavelength by the passive radiometer included in the Cassini Radar instrument. The data reported were accumulated from 69 separate observational segments in Titan passes from Ta (October 2004) through T30 (May 2007) and include emission from 94% of Titan's surface. They are diverse in the key observing parameters of emission angle, polarization, and spatial resolution, and their reduction into calibrated global mosaic maps involved several steps. Analysis of the polarimetry obtained at low to moderate resolution (50+ km) enabled integration of the radiometry into a single mosaic of the equivalent brightness temperature at normal incidence with a relative precision of about 1 K. The Huygens probe measurement of Titan's surface temperature and radiometry obtained on Titan's dune fields allowed us to infer an absolute calibration estimated to be accurate to a level approaching 1 K. The results provide evidence for a surface that is complex and varied on large scales. The radiometry primarily constrains physical properties of the surface, where we see strong evidence for subsurface (volume) scattering as a dominant mechanism that determines the emissivity, with the possibility of a fluffy or graded-density surface layer in many regions. The results are consistent with, but not necessarily definitive of a surface composition resulting from the slow deposition and processing of organic compounds from the atmosphere. ?? 2008 Elsevier Inc.

  7. The source of widespread 3-$\\mu$m absorption in Jupiter's clouds: Constraints from 2000 Cassini VIMS observations

    CERN Document Server

    Sromovsky, Lawrence

    2015-01-01

    The Cassini flyby of Jupiter in 2000 provided spatially resolved spectra of Jupiter's atmosphere using the Visual and Infrared Mapping Spectrometer (VIMS). These spectra contain a strong absorption at wavelengths from about 2.9 $\\mu$m to 3.1 $\\mu$m, previously noticed in a 3-$\\mu$m spectrum obtained by the Infrared Space Observatory (ISO) in 1996. While Brooke et al. (1998, Icarus 136, 1-13) were able to fit the ISO spectrum very well using ammonia ice as the sole source of particulate absorption, Sromovsky and Fry (2010, Icarus 210, 211-229), using significantly revised NH$_3$ gas absorption models, showed that ammonium hydrosulfide (NH$_4$SH) provided a better fit to the ISO spectrum than NH$_3$ , but that the best fit was obtained when both NH$_3$ and NH$_4$SH were present. Although the large FOV of the ISO instrument precluded identification of the spatial distribution of these two components, the VIMS spectra at low and intermediate phase angles show that 3-$\\mu$m absorption is present in zones and belts...

  8. FMT (Flight Software Memory Tracker) For Cassini Spacecraft-Software Engineering Using JAVA

    Science.gov (United States)

    Kan, Edwin P.; Uffelman, Hal; Wax, Allan H.

    1997-01-01

    The software engineering design of the Flight Software Memory Tracker (FMT) Tool is discussed in this paper. FMT is a ground analysis software set, consisting of utilities and procedures, designed to track the flight software, i.e., images of memory load and updatable parameters of the computers on-board Cassini spacecraft. FMT is implemented in Java.

  9. Using AUTORAD for Cassini File Uplinks: Incorporating Automated Commanding into Mission Operations

    Science.gov (United States)

    Goo, Sherwin

    2014-01-01

    As the Cassini spacecraft embarked on the Solstice Mission in October 2010, the flight operations team faced a significant challenge in planning and executing the continuing tour of the Saturnian system. Faced with budget cuts that reduced the science and engineering staff by over a third in size, new and streamlined processes had to be developed to allow the Cassini mission to maintain a high level of science data return with a lower amount of available resources while still minimizing the risk. Automation was deemed an important key in enabling mission operations with reduced workforce and the Cassini flight team has made this goal a priority for the Solstice Mission. The operations team learned about a utility called AUTORAD which would give the flight operations team the ability to program selected command files for radiation up to seven days in advance and help minimize the need for off-shift support that could deplete available staffing during the prime shift hours. This paper will describe how AUTORAD is being utilized by the Cassini flight operations team and the processes that were developed or modified to ensure that proper oversight and verification is maintained in the generation and execution of radiated command files.

  10. In-Flight Position Calibration of the Cassini Articulated Reaction Wheel Assembly

    Science.gov (United States)

    Brown, Todd S.

    2012-01-01

    NASA's long-lived Cassini-Huygens spacecraft is currently in its 14th year of flight and in the midst of its second, and final, extended mission. Cassini is a massive interplanetary spacecraft that is three axis stabilized and can maintain attitude control using either its reaction control system thrusters or using reaction wheel control. Cassini has four identical reaction wheels, of which three are mutually orthogonal and have a fixed orientation. The fourth reaction wheel has an articulation motor that allows this reaction wheel to be aligned with the momentum direction of any of the other three fixed reaction wheels. The articulation motor allows this reaction wheel to be used as a replacement for any of the other three wheels without any performance degradation. However, due to limitations in the design of this backup system, there are few telemetric indications of the orientation of this reaction wheel following an articulation. This investigation serves to outline the procedures that have been developed by the Cassini Attitude and Articulation Control Subsystem to calibrate the position of the articulated reaction wheel assembly in the event that the momentum direction of this reaction wheel must be reoriented.

  11. Galileo SSI and Cassini ISS Observations of Io's Pele Hotspot: Temperatures, Areas, and Variation with Time

    Science.gov (United States)

    Radebaugh, J.; McEwen, A. S.; Milazzo, M.; Davies, A. G.; Keszthelyi, L. P.; Geissler, P.

    2002-01-01

    Temperatures of Io's Pele hotspot were found using dual-filter observations from Galileo and Cassini. Temperatures average 1375 K, but vary widely over tens of minutes. Dropoff in emission with rotation consistent with lava fountaining at a lava lake. Additional information is contained in the original extended abstract.

  12. Cassini Radio Science Experiments on Saturn and Titan Preserved Because of Lewis Analysis

    Science.gov (United States)

    Wilson, Jeffrey D.

    1999-01-01

    The Cassini mission to Saturn is an international venture with participation from NASA, the European Space Agency, and the Italian Space Agency. The Cassini spacecraft was launched from Cape Canaveral in October 1997 and is scheduled to arrive at Saturn in July 2004. After arrival, the spacecraft will orbit Saturn about 60 times over a period of 4 years. During this time, the Cassini Radio Science Subsystem will be used to investigate the atmosphere and rings of Saturn and the atmosphere of its largest moon, Titan--which is larger than Mercury and is the only moon in our solar system with a dense atmosphere. A critical component in Cassini s Radio Science Subsystem is a traveling-wave tube (TWT) that was designed at the NASA Lewis Research Center and built by Hughes Electronic Dynamics Division (ref. 1). This TWT will amplify downlink microwave signals at a frequency of 32 GHz for the Deep Space Network and will be involved in a number of experiments. These include occultation experiments in which the microwave signal will be beamed through rings and atmospheres toward Earth. Researchers will analyze the received signals to determine the sizes and distributions of the particles in the rings and the structure and composition of the atmospheres. The Radio Science Subsystem also will also be used to more accurately determine the mass and size of Saturn and its moons, to investigate the solar corona, and to search for gravity waves from outside the solar system.

  13. Galileo SSI and Cassini ISS Observations of Io's Pele Hotspot: Temperatures, Areas, and Variation with Time

    Science.gov (United States)

    Radebaugh, J.; McEwen, A. S.; Milazzo, M.; Davies, A. G.; Keszthelyi, L. P.; Geissler, P.

    2002-01-01

    Temperatures of Io's Pele hotspot were found using dual-filter observations from Galileo and Cassini. Temperatures average 1375 K, but vary widely over tens of minutes. Dropoff in emission with rotation consistent with lava fountaining at a lava lake. Additional information is contained in the original extended abstract.

  14. Cassini Radio Science Experiments on Saturn and Titan Preserved Because of Lewis Analysis

    Science.gov (United States)

    Wilson, Jeffrey D.

    1999-01-01

    The Cassini mission to Saturn is an international venture with participation from NASA, the European Space Agency, and the Italian Space Agency. The Cassini spacecraft was launched from Cape Canaveral in October 1997 and is scheduled to arrive at Saturn in July 2004. After arrival, the spacecraft will orbit Saturn about 60 times over a period of 4 years. During this time, the Cassini Radio Science Subsystem will be used to investigate the atmosphere and rings of Saturn and the atmosphere of its largest moon, Titan--which is larger than Mercury and is the only moon in our solar system with a dense atmosphere. A critical component in Cassini s Radio Science Subsystem is a traveling-wave tube (TWT) that was designed at the NASA Lewis Research Center and built by Hughes Electronic Dynamics Division (ref. 1). This TWT will amplify downlink microwave signals at a frequency of 32 GHz for the Deep Space Network and will be involved in a number of experiments. These include occultation experiments in which the microwave signal will be beamed through rings and atmospheres toward Earth. Researchers will analyze the received signals to determine the sizes and distributions of the particles in the rings and the structure and composition of the atmospheres. The Radio Science Subsystem also will also be used to more accurately determine the mass and size of Saturn and its moons, to investigate the solar corona, and to search for gravity waves from outside the solar system.

  15. Equatorial belt of Titan: Aaru Region as seen by VIMS/Cassini

    Science.gov (United States)

    Florian Brossier, Jeremy; Rodriguez, Sébastien; Maltagliati, Luca; Le Mouélic, Stéphane; Solomonidou, Anezina; Coustenis, Athena; Hirtzig, Mathieu; Jaumann, Ralf; Brown, Robert H.

    2016-10-01

    Since eleven years of observation, near-infrared imaging data from the Visual and Infrared Mapping Spectrometer (VIMS) onboard Cassini1 reveal a variety of surface units that are compositionally and structurally distinct2, 3. The analysis of these units enables constraining the surface composition of Titan, which is of prime importance for modelling Titan's interior, surface, and atmosphere, particularly in the search for an endogenic methane source. For this study, we investigate a selection of units of interest seen in VIMS data by comparatively applying an empirical correction4, 5 and a radiative transfer code6-8 in order to correct for atmospheric contributions and retrieve surface albedo. SAR swaths from the Radar instrument are also used for geomorphological mapping purposes. We focus on the region of Aaru, located in the equatorial belt and centered at 10°N and 340°W, where several geological features have been identified: (1) infrared-brown dunes material; (2) a strongly eroded impact crater named Paxsi9 (3) mountainous and infrared-bright plateaus; and (4) infrared-blue areas devoid of dunes (similar to those seen in other regions probably enriched in water-ice, such as Chusuk Planitia10). By using our radiative transfer model, we estimate the surface albedo of regions of our interest within different infrared units of the Aaru region and compare with spectra of surface candidates, starting with water-ice and tholins. As seen in the similar study over Sinlap crater and its surroundings11, this method of analysis allows understanding of the compositional and structural relations between the different spectral units.References: 1 Brown, R. H. et al. (2005) SSR. 2 Barnes, J. W. et al. (2007) Icarus, 186 (1). 3 Soderblom, L. A. et al. (2007) PSS, 55 (13). 4 Cornet, T. et al. (2012) Icarus, 218 (2). 5 Le Mouélic, S. et al. (2012) PSS, 73 (1). 6 Hirtzig, M. et al. (2013) Icarus, 226 (1). 7 Solomonidou, A. et al. (2014) JGR, 119 (8). 8 Maltagliati, L. et al

  16. Titan's mid-latitude surface regions with Cassini VIMS and SAR

    Science.gov (United States)

    Solomonidou, Anezina; Coustenis, Athena; Drossart, Pierre; Brown, Robert H.; Sohl, Frank; Stephan, Katrin; Jaumann, Ralf; Rodriguez, Sebastien; Bratsolis, Emmanuel; Schmitt, Bernard; Le Gall, Alice; Lopes, Rosaly; Malaska, Michael; Janssen, Michael; Maltagliati, Luca; Villanueva, Edward; Matsoukas, Christos

    2016-07-01

    We investigate the surface of Saturn's moon Titan by means of two Cassini instruments used in synergy. We apply a radiative transfer code to VIMS hyperspectral data to correct the strong atmospheric contribution and extract information on surface composition (Hirtzig et al. 2014; Solomonidou et al. 2014; 2015). We then put this in the context of terrain morphology by use of denoised Synthetic Aperture Radar (SAR) images (Bratsolis et al. 2012). We examine here the mid-latitude zones extending from 50ºN to 50ºS, which includes key geological features identified in Lopes et al. (2010, 2015) and Malaska et al. (2015): mountains, plains, labyrinths, dune fields, and possible cryovolcanic and/or evaporitic deposits. We find that many of the different units show compositional variations while units of significant geomorphological differences seem to consist of very similar material mixtures. The Huygens landing site and the candidate evaporitic regions are compositionally similar to the variable plains. We also find that temporal variations of surface albedo exist for two of the candidate cryovolcanic regions Tui Regio and Sotra Patera, suggesting the presence of surface activity, while a number of other regions such as Hotei Regio and the undifferentiated plains remain unchanged (Solomonidou et al. 2015). The surface albedo variations, together with the presence of volcanic-like morphological features, suggest that the active regions are possibly related to the deep interior, possibly via cryovolcanic processes (with important implications for the satellite's astrobiological potential) as also indicated by recent interior structure models of Titan and corresponding calculations of the spatial pattern of maximum tidal stresses (Sohl et al. 2014). In previous studies (Lopes et al. 2015; Solomonidou et al. 2015) we showed that a variety of surface processes could be linked to the formation of the various geomorphological units (aeolian, fluvial, sedimentary, lacustrine

  17. Clumping in the Cassini Division and C Ring: Constraints from Stellar Occultations

    Science.gov (United States)

    Colwell, J. E.; Jerousek, R. G.; Esposito, L. W.

    2014-12-01

    Particles in Saturn's rings are engaged in a constant tug-of-war between interparticle gravitational and adhesive forces that lead to clumping, on the one hand, and Keplerian shear that inhibits accretion on the other. Depending on the surface mass density of the rings and the local orbital velocity, ephemeral clumps or self-gravity wakes can form, giving the rings granularity on the scale of the most-unstable length scale against gravitational collapse. The A ring and many regions of the B ring are dominated by self-gravity wakes with a typical radial wavelength of ~50-100 m. A characteristic of self-gravity wakes is that they can effectively shadow the relatively empty spaces in between them, depending on viewing geometry. This leads to geometry-dependent measurements of optical depth in occultations of the rings. The C ring and Cassini Division have significantly lower surface mass densities than the A and B ring such that in most of these regions the most-unstable wavelength is comparable to the size of the ring particles (~1 m) so that self-gravity wake formation is not expected nor have its characteristics in various measurements been observed. Here we present measurements of the optical depth of the C ring and Cassini Division with the Cassini Ultraviolet Imaging Spectrograph (UVIS) showing variations with viewing geometry in the "ramp" regions and the Cassini Division "triple band". These variations are characteristic of self-gravity wakes. We place limits on clumping in other regions of the C ring and Cassini Division.

  18. Comparisons of cirrus cloud properties between polluted and pristine air based on in-situ observations from the NSF HIPPO, EU INCA and NASA ATTREX campaigns

    Science.gov (United States)

    Diao, M.; Schumann, U.; Jensen, J. B.; Minikin, A.

    2015-12-01

    The radiative forcing of cirrus clouds is influenced by microphysical (e.g., ice crystal number concentration and size distribution) and macroscopic properties. Currently it is still unclear how the formation of cirrus clouds and their microphysical properties are influenced by anthropogenic emissions. In this work, we use airborne in-situ observations to compare cirrus cloud properties between polluted and pristine regions. Our dataset includes: the NSF HIAPER Pole-to-Pole Observations (HIPPO) Global campaign (2009-2011), the EU Interhemispheric Differences In Cirrus Properties from Anthropogenic Emissions (INCA) campaign (2000) and the NASA Airborne Tropical Tropopause Experiment (ATTREX) campaign (2014). The combined dataset include observations of both extratropical (HIPPO and INCA) and tropical (ATTREX) cirrus, over the Northern and Southern Hemispheres. We use the in-situ measured carbon monoxide (CO) mixing ratio as a pollution indicator, and compare