WorldWideScience

Sample records for repeated observations spaced

  1. Climate Observations from Space

    Science.gov (United States)

    Briggs, Stephen

    2016-07-01

    The latest Global Climate Observing System (GCOS) Status Report on global climate observations, delivered to the UNFCCC COP21 in November 2016, showed how satellite data are critical for observations relating to climate. Of the 50 Essential Climate Variables (ECVs) identified by GCOS as necessary for understanding climate change, about half are derived only from satellite data while half of the remainder have a significant input from satellites. Hence data from Earth observing satellite systems are now a fundamental requirement for understanding the climate system and for managing the consequences of climate change. Following the Paris Agreement of COP21 this need is only greater. Not only will satellites have to continue to provide data for modelling and predicting climate change but also for a much wider range of actions relating to climate. These include better information on loss and damage, resilience, improved adaptation to change, and on mitigation including information on greenhouse gas emissions. In addition there is an emerging need for indicators of the risks associated with future climate change which need to be better quantified, allowing policy makers both to understand what decisions need to be taken, and to see the consequences of their actions. The presentation will set out some of the ways in which satellite data are important in all aspects of understanding, managing and predicting climate change and how they may be used to support future decisions by those responsible for policy related to managing climate change and its consequences.

  2. Assessing agreement with repeated measures for random observers.

    Science.gov (United States)

    Chen, Chia-Cheng; Barnhart, Huiman X

    2011-12-30

    Agreement studies are often concerned with assessing whether different observers for measuring responses on the same subject or sample can produce similar results. The concordance correlation coefficient (CCC) is a popular index for assessing the closeness among observers for quantitative measurements. Usually, the CCC is used for data without and with replications based on subject and observer effects only. However, we cannot use this methodology if repeated measurements rather than replications are collected. Although there exist some CCC-type indices for assessing agreement with repeated measurements, there is no CCC for random observers and random time points. In this paper, we propose a new CCC for repeated measures where both observers and time points are treated as random effects. A simulation study demonstrates our proposed methodology, and we use vertebral body data and image data for illustrations.

  3. Recursion Of Binary Space As A Foundation Of Repeatable Programs

    Directory of Open Access Journals (Sweden)

    Jeremy Horne

    2006-10-01

    Full Text Available Every computation, including recursion, is based on natural philosophy. Our world may be expressed in terms of a binary logical space that contains functions that act simultaneously as objects and processes (operands and operators. This paper presents an outline of the results of research about that space and suggests routes for further inquiry. Binary logical space is generated sequentially from an origin in a standard coordinate system. At least one method exists to show that each of the resulting 16 functions repeats itself by repeatedly forward-feeding outputs of a function operating over two others as new operands of the original function until the original function appears as an output, thus behaving as an apparent homeostatic automaton. As any space of any dimension is composed of one or more of these functions, so the space is recursive, as well. Semantics gives meaning to recursive structures, computer programs and fundamental constituents of our universe being two examples. Such thoughts open inquiry into larger philosophical issues as free will and determinism.

  4. Genus-specific protein binding to the large clusters of DNA repeats (short regularly spaced repeats) present in Sulfolobus genomes

    DEFF Research Database (Denmark)

    Peng, Xu; Brügger, Kim; Shen, Biao

    2003-01-01

    Short regularly spaced repeats (SRSRs) occur in multiple large clusters in archaeal chromosomes and as smaller clusters in some archaeal conjugative plasmids and bacterial chromosomes. The sequence, size, and spacing of the repeats are generally constant within a cluster but vary between clusters...... that are identical in sequence to one of the repeat variants in the S. solfataricus chromosome. Repeats from the pNOB8 cluster were amplified and tested for protein binding with cell extracts from S. solfataricus. A 17.5-kDa SRSR-binding protein was purified from the cell extracts and sequenced. The protein is N...... terminally modified and corresponds to SSO454, an open reading frame of previously unassigned function. It binds specifically to DNA fragments carrying double and single repeat sequences, binding on one side of the repeat structure, and producing an opening of the opposite side of the DNA structure. It also...

  5. Why Observable Space Is Solely Three Dimensional

    CERN Document Server

    Rabinowitz, Mario

    2015-01-01

    Quantum (and classical) binding energy considerations in n-dimensional space indicate that atoms (and planets) can only exist in three-dimensional space. This is why observable space is solely 3-dimensional. Both a novel Virial theorem analysis, and detailed classical and quantum energy calculations for 3-space circular and elliptical orbits indicate that they have no orbital binding energy in greater than 3-space. The same energy equation also excludes the possibility of atom-like bodies in strictly 1 and 2-dimensions. A prediction is made that in the search for deviations from r^-2 of the gravitational force at sub-millimeter distances such a deviation must occur at < ~ 10^-10 m (or < ~10^-12 m considering muoniom), since atoms would disintegrate if the curled up dimensions of string theory were larger than this. Callender asserts that the often-repeated claim in previous work that stable orbits are possible in only three dimensions is not even remotely established. The binding energy analysis herein ...

  6. Observing the Anthropocene from Space

    Science.gov (United States)

    Dittus, Hansjörg

    2016-07-01

    Influence of mankind on Earth's climate is evident. The growing population using the resources available, especially by burning goal, oil and gas, changes the composition of the Earth's atmosphere with the result of a continuously increasing temperature. Effects are not limited to the regional scale but are evident on the whole planet, meanwhile named Anthropocene. According to this global influence, it's necessary to also extend monitoring to the entire planet. Space-based observation systems are not limited by any artificial borders and are in principle able, to cover the whole Earth. In principle, two different ways of observation can be selected: Either a dedicated spacecraft will be send into low earth orbit (LEO) or existing platforms are used. Advantages of satellites are the more or less freely selectable orbit (with orbits covering also the polar regions) and the possible adaption of spacecraft platform for the dedicated instrument. On the other hand platforms like the ISS space station enable continuous long term coverage with different instruments. The drawback of an only limited coverage based on the orbit inclination is made up by the possibility to service systems on the station. Furthermore different generations of sensors can be run in parallel and therefore cross calibrated if needed. This paper reviews the currently available sensors types and discusses potential future needs. Included in this discussion is the international space station as an already available platform for earth observation. Furthermore, discussion should also take into account, that an increasing number of constellations with dozens or even thousand satellites are planned. Are these constellations also an option for an increased temporal and spatial monitoring of the Earth?

  7. COSMOS Hubble Space Telescope Observations

    CERN Document Server

    Scoville, N Z; Blain, A W; Calzetti, D; Comastri, A; Capak, P; Carilli, C; Carlstrom, J E; Carollo, C M; Colbert, J; Daddi, E; Ellis, Richard S; Elvis, M; Ewald, S P; Fall, M; Franceschini, A; Giavalisco, M; Green, W; Griffiths, R E; Guzzo, L; Hasinger, G; Impey, C; Kneib, J P; Koda, J; Koekemoer, A; Lefèvre, O; Lilly, S; Liu, C T; McCracken, H J; Massey, R; Mellier, Y; Miyazaki, S; Mobasher, B; Mould, J; Norman, C; Réfrégier, A; Renzini, A; Rhodes, J; Rich, M; Sanders, D B; Schiminovich, D; Schinnerer, E; Scodeggio, M; Sheth, K; Shopbell, P L; Taniguchi, Y; Tyson, N; Urry, C M; Van Waerbeke, L; Vettolani, P; White, S D M; Yan, L

    2006-01-01

    The Cosmic Evolution Survey (COSMOS) was initiated with an extensive allocation (590 orbits in Cycles 12-13) using the Hubble Space Telescope (HST) for high resolution imaging. Here we review the characteristics of the HST imaging with the Advanced Camera for Surveys (ACS) and parallel observations with NICMOS and WFPC2. A square field (1.8$\\sq$\\deg) has been imaged with single-orbit ACS I-F814W exposures with 50% completeness for sources 0.5\\arcsec in diameter at I$_{AB} $ = 26.0 mag. The ACS imaging is a key part of the COSMOS survey, providing very high sensitivity and high resolution (0.09\\arcsec FWHM, 0.05\\arcsec pixels) imaging and detecting a million objects. These images yield resolved morphologies for several hundred thousand galaxies. The small HST PSF also provides greatly enhanced sensitivity for weak lensing investigations of the dark matter distribution.

  8. Observing the Anthropocene from Space

    Science.gov (United States)

    Burrows, John

    The industrial revolution, which began in the UK in the late 18th century, has been fuelled by the use of cheap energy from fossil fuel combustion. It has facilitated a dramatic rise in both the human population, now above 7 Billion with 50% now living in urban agglomerations, and its standard of living. It is anticipated that by 2050 there will be of the order of 8.3 to 10 billion people, 75% living in cities. Anthropogenic activity has resulted in pollution from the local to the global scale changes in land use, the destruction of stratospheric ozone, the modification of biogeochemical cycling, acid deposition, impacted on ecosystems and ecosystem services, destruction of biodiversity and climate change. The impact of man has moved the earth from the Holocene to the new geological epoch of the Anthropocene. To improve our understanding of the earth atmosphere system and the accuracy of the prediction of its future changes, knowledge of the amounts and distributions of trace atmospheric constituents are essential -“One cannot manage what is not measured”. An integrated observing system, comprising ground and space based segments is required to improve our science and to provide an evidence base needed for environmental policymakers. Passive remote sensing measurements made of the up-welling radiation at the top of the atmosphere from instrumentation on space borne platforms provide a unique opportunity to retrieve globally atmospheric composition. This presentation describes results from the SCIAMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY on ESA Envsiat 2002 to 2012) and its spin offs GOME (Global Ozone Monitoring Experiment ESA ERS-2 1995 to 2011) and GOME-2 (ESA/EUMETSAT Metop series). The potential of the SCIAMACHY successors Sentinel 5, CarbonSat, and SCIA-ISS will also be addressed.

  9. Estimating thermal performance curves from repeated field observations

    Science.gov (United States)

    Childress, Evan; Letcher, Benjamin H.

    2017-01-01

    Estimating thermal performance of organisms is critical for understanding population distributions and dynamics and predicting responses to climate change. Typically, performance curves are estimated using laboratory studies to isolate temperature effects, but other abiotic and biotic factors influence temperature-performance relationships in nature reducing these models' predictive ability. We present a model for estimating thermal performance curves from repeated field observations that includes environmental and individual variation. We fit the model in a Bayesian framework using MCMC sampling, which allowed for estimation of unobserved latent growth while propagating uncertainty. Fitting the model to simulated data varying in sampling design and parameter values demonstrated that the parameter estimates were accurate, precise, and unbiased. Fitting the model to individual growth data from wild trout revealed high out-of-sample predictive ability relative to laboratory-derived models, which produced more biased predictions for field performance. The field-based estimates of thermal maxima were lower than those based on laboratory studies. Under warming temperature scenarios, field-derived performance models predicted stronger declines in body size than laboratory-derived models, suggesting that laboratory-based models may underestimate climate change effects. The presented model estimates true, realized field performance, avoiding assumptions required for applying laboratory-based models to field performance, which should improve estimates of performance under climate change and advance thermal ecology.

  10. Estimating thermal performance curves from repeated field observations.

    Science.gov (United States)

    Childress, Evan S; Letcher, Benjamin H

    2017-03-08

    Estimating thermal performance of organisms is critical for understanding population distributions and dynamics and predicting responses to climate change. Typically, performance curves are estimated using laboratory studies to isolate temperature effects, but other abiotic and biotic factors influence temperature-performance relationships in nature reducing these models' predictive ability. We present a model for estimating thermal performance curves from repeated field observations that includes environmental and individual variation. We fit the model in a Bayesian framework using MCMC sampling, which allowed for estimation of unobserved latent growth while propagating uncertainty. Fitting the model to simulated data varying in sampling design and parameter values demonstrated that the parameter estimates were accurate, precise, and unbiased. Fitting the model to individual growth data from wild trout revealed high out-of-sample predictive ability relative to laboratory-derived models, which produced more biased predictions for field performance. The field-based estimates of thermal maxima were lower than those based on laboratory studies. Under warming temperature scenarios, field-derived performance models predicted stronger declines in body size than laboratory-derived models, suggesting that laboratory-based models may underestimate climate change effects. The presented model estimates true, realized field performance, avoiding assumptions required for applying laboratory-based models to field performance, which should improve estimates of performance under climate change and advance thermal ecology. This article is protected by copyright. All rights reserved.

  11. Observing BVOC emissions from Space

    Science.gov (United States)

    Oetjen, Hilke; Hewson, William; Comyn-Platt, Edward M.; Barkley, Michael P.; Bösch, Hartmut

    2016-04-01

    Formaldehyde (HCHO) is formed in the atmosphere as an intermediate from the oxidation of methane and other hydrocarbons such as isoprene, but also from combustion processes. Further, global and accurate measurements of HCHO from space are important since they can be used to infer global isoprene emission (e.g. Barkley et al., 2013), the primary biogenic volatile organic compound (BVOC) that cannot be monitored from space directly. However, isoprene is an important source of ozone and secondary organic aerosol, and a sink for the hydroxyl radical. HCHO absorbs in the ultraviolet wavelengths range and can therefore be detected by scattered sunlight absorption spectroscopy. Here we present measurements with the GOME-2 instrument. The first of the 3 GOME-2 instruments has been flying on MetOp-A since 2006 and MetOp-B has been launched in 2012. MetOp-C is expected to be launched in 2018. The University of Leicester retrieval (Hewson et al., 2015) is a well characterised state-of-the-art algorithm which has been used to infer HCHO vertical columns from MetOp-A, and more recently from MetOp-B. The results have been employed for creating a global, multi-year time series. This dataset has been exploited to analyse regional year-to-year variations in HCHO abundances and also to test emission models via comparisons to GEOS-Chem simulations. Barkley, M. P., et al. (2013), J. Geophys. Res. Atmos., 118, 6849-6868, doi:10.1002/jgrd.50552 Hewson, W., et al. (2015), Atmos. Meas. Tech., 8, 4055-4074, doi:10.5194/amt-8-4055-2015

  12. Space-Based Observation Technology

    Science.gov (United States)

    2007-11-02

    jusqu’ici par des systèmes aéroportés, par des systèmes spatiaux. Les capteurs spatiaux sont des capteurs radar et optiques . Les capteurs optiques ...de l’observation de la terre à partir de capteurs spatiaux offre de nombreux avantages par rapport à l’observation à partir de capteurs terrestres...résolution optique . Le SAR a également d’autres fonctionnalités telles que la classification basée sur les techniques Doppler ou la polarimétrie, la

  13. Observational modeling of topological spaces

    Energy Technology Data Exchange (ETDEWEB)

    Molaei, M.R. [Department of Mathematics, Shahid Bahonar University of Kerman, Kerman 76169-14111 (Iran, Islamic Republic of)], E-mail: mrmolaei@mail.uk.ac.ir

    2009-10-15

    In this paper a model for a multi-dimensional observer by using of the fuzzy theory is presented. Relative form of Tychonoff theorem is proved. The notion of topological entropy is extended. The persistence of relative topological entropy under relative conjugate relation is proved.

  14. Observation of Pollution from Space

    Science.gov (United States)

    Burrows, J. P.; Richter, A.; Bovensmann, H.; Buchwitz, M.; Andrés Hernández, M. D.; Hilboll, A.; Schoenhardt, A.; Blechschmidt, A.; Alvarado, L.; Wittrock, F.

    2016-12-01

    The rapid growth of population since the industrial revolution has led to large changes in surface emissions and land use change. It is now over 30 years since the SCIAMACHY project was initiated. This project has led to the GOME (ESA ERS-2 1995-2011), SCIAMACHY (ESA Envisat 2002 to 2011) GOME-2 (EUMETSAT/ESA Metop A, 2006 to present, Metop B 2012 to present, Metop C planned launch 2018) and the spin offs OMI (NASA AURA 2004-present) . This presentation addresses observations of tropospheric trace gas pollutants retrieved these instruments with a focus on recent studies of the ozone precursors NO2, HCHO and CHO.CHO, the halogen oxides BrO, IO and CH4 and CO2. It will discuss the objectives of the DLR HALO EMeRGe mission. The latter is research mission combining satelltie and aircraft observations, whihc aims to study pollution from major pollution centers in Europe and Asia, and is planned to take palce in 2017 and 2018.

  15. Quantifying Snow Volume Uncertainty from Repeat Terrestrial Laser Scanning Observations

    Science.gov (United States)

    Gadomski, P. J.; Hartzell, P. J.; Finnegan, D. C.; Glennie, C. L.; Deems, J. S.

    2014-12-01

    Terrestrial laser scanning (TLS) systems are capable of providing rapid, high density, 3D topographic measurements of snow surfaces from increasing standoff distances. By differencing snow surface with snow free measurements within a common scene, snow depths and volumes can be estimated. These data can support operational water management decision-making when combined with measured or modeled snow densities to estimate basin water content, evaluate in-situ data, or drive operational hydrologic models. In addition, change maps from differential TLS scans can also be used to support avalanche control operations to quantify loading patterns for both pre-control planning and post-control assessment. However, while methods for computing volume from TLS point cloud data are well documented, a rigorous quantification of the volumetric uncertainty has yet to be presented. Using repeat TLS data collected at the Arapahoe Basin Ski Area in Summit County, Colorado, we demonstrate the propagation of TLS point measurement and cloud registration uncertainties into 3D covariance matrices at the point level. The point covariances are then propagated through a volume computation to arrive at a single volume uncertainty value. Results from two volume computation methods are compared and the influence of data voids produced by occlusions examined.

  16. Earth observations from space: A dream deferred?

    Science.gov (United States)

    McElroy, John H.

    Earth observations from space are one of the great successes of the space age. However, because the promise of this technology is a long way from being realized, the joy of success is tinged with disappointment for both researchers and operational users of the data. U.S. Earth observation programs have been in turmoil since their inception, with confusion coming to a crescendo over the past 6 years. Neither the executive or legislative branches of the government have shown that they can successfully manage this technological capability created by the space program.

  17. Repeating hemorrhage after radiotherapy for glioma. Radiological and histological observations

    Energy Technology Data Exchange (ETDEWEB)

    Kawano, Hirokazu [Miyakonojo Medical Association Hospital, Miyazaki (Japan); Wakisaka, Shinichiro; Kubota, Toshihiko; Hosotani, Kazuo

    1998-02-01

    A case of radiation necrosis which was observed six years after radiotherapy for a glioma in the right parietal lobe is reported. This patient developed hemiparesis, and radiological examinations showed similar findings consisted with recurrent glioma. Histological examination disclosed that the lesion is correspond to the radiation necrosis. (author)

  18. Development of volcano monitoring technique using repeating earthquakes observed by the Volcano Observation Network of NIED

    Science.gov (United States)

    Kohno, Y.; Ueda, H.; Kimura, H.; Nagai, M.; Miyagi, Y.; Fujita, E.; Kozono, T.; Tanada, T.

    2012-12-01

    After the Grate East Japan Earthquake (M9.0) on March 11, 2011, the M6.4 earthquake occurred beneath Mt. Fuji on March 15, 2011. Although the hypocenter seemed to be very close to an assumed magma chamber of Fuji volcano, no anomalies in volcanic activity have been observed until August 2012. As an example, after the M6.1 earthquake occurred in 1998 at southwest of Iwate volcano, a change of seismic velocity structure (e.g. Nishimura et al., 2000) was observed as well as active seismicity and crustal deformation. It had affected waveforms of repeating earthquakes occurring at a plate subduction zone, that is, the waveform similarities were reduced just after the earthquake due to upwelling of magma. In this study, first we analyzed for Mt. Fuji where such changes are expected by the occurrence of the earthquake to try to develop a tool for monitoring active volcanoes using the Volcano Observation network (V-net) data. We used seismic waveform data of repeating earthquakes observed by short period seismometers of V-net and the High Sensitivity Seismograph Network Japan (Hi-net) stations near Fuji volcano after 2007. The seismic data were recorded with a sampling rate of 100 Hz, and we applied 4-8 Hz band pass filter to reduce noise. The repeating earthquakes occurred at the plate subduction zone and their catalog is compiled by Hi-net data (Kimura et al., 2006). We extracted repeating earthquake groups that include earthquakes before and after the M6.4 earthquake on March 15, 2011. A waveform of the first event of the group and waveforms of the other events are compared and calculated cross-correlation coefficients. We adjusted P wave arrivals of each event and calculate the coefficients and lag times of the latter part of the seismic waves with the time window of 1.25 s. We searched the best fit maximizing the cross-correlation coefficients with 0.1 s shift time at each time window. As a result we found three remarkable points at this time. [1] Comparing lag times

  19. Observing photons in space a guide to experimental space astronomy

    CERN Document Server

    Pauluhn, Anuschka; Culhane, J; Timothy, J; Wilhelm, Klaus; Zehnder, Alex

    2013-01-01

    An ideal resource for lecturers, this book provides a comprehensive review of experimental space astronomy. The number of astronomers whose knowledge and interest is concentrated on interpreting observations has grown substantially in the past decades; yet, the number of scientists who are familiar with and capable of dealing with instrumentation has dwindled.  All of the authors of this work are leading and experienced experts and practitioners who have designed, built, tested, calibrated, launched and operated advanced observing equipment for space astronomy. This book also contains concise information on the history of the field, supported by appropriate references. Moreover, scientists working in other fields will be able to get a quick overview of the salient issues of observing photons in any one of the various energy, wavelength and frequency ranges accessible in space. This book was written with the intention to make it accessible to advanced undergraduate and graduate students.

  20. Crustal deformation in the Kumano Basin along the Nankai Trough inferred from repeated seafloor geodetic observations

    Science.gov (United States)

    Watanabe, T.; Tadokoro, K.; Sugimoto, S.; Okuda, T.; Muto, D.; Kimoto, A.; Miyata, K.; Kuno, M.

    2008-12-01

    At the Nankai Trough (NT), the Philippine Sea plate (PH) subducts beneath the southwest Japan at a rate of about 4-6 cm/yr, where great interplate earthquakes have repeatedly occurred every 100-200 years. A number of researchers have investigated crustal deformation caused by subduction of the PH based on geodetic measurements as represented by GPS observation. However it is difficult to infer the plate coupling strength in offshore areas, due to the poverty of offshore geodetic data. From a viewpoint of disaster mitigation, it is important to know the updip and downdip limit of the plate locking depth. For this issue, we have conducted observations of the seafloor crustal deformations around the NT using a GPS/Acoustic technique since 2004. In this system, we estimate the position of a surveying vessel by Kinematic GPS analysis and measure the distance between the vessel and the benchmark on the sea floor by Acoustic measurements. Next we determine the location of the benchmark. For the repeatability of observation, the location of benchmark is determined within a precision of 2-3 cm at horizontal components (Tadokoro et al., 2006). In the Kumano Basin, we have two seafloor benchmarks, which are located about 60 and 80 km away from the deformation front of the NT. The observations from 2005 to 2008 have illustrated that these benchmarks are moving at rates of about 5-6 cm/yr with velocity uncertainties of 1-3 cm/yr relative to the Amurian plate. In this study, in order to estimate interplate coupling at the NT, we calculated surface deformations accompanied with plate subduction in an elastic half-space and compared them with on- and offshore GPS velocities. Then, we investigated the effect of observation for the seafloor crustal deformations on slip resolution on the plate interface. We conclude that offshore crustal deformation data provide good constraints for the estimation of fault slips at the shallower part of the plate interface, especially at the depths

  1. Analysis of repeated measurements from medical research when observations are missing

    OpenAIRE

    Walker, K.

    2007-01-01

    Subject dropout is a common problem in repeated measurements health stud ies. Where dropout is related to the response, the results obtained can be substantially biased. The research in this thesis is motivated by a repeated measurements asthma clinical trial with substantial patient dropout. In practice the extent to which missing observations affect parameter esti mates and their efficiency is not clear. Through extensive simulation studies under various scenarios and missing data mechanism...

  2. Theoretical limit of repeater spacing in an optical transmission line utilizing Raman amplification

    Science.gov (United States)

    Nakashima, T.; Seikai, S.; Nakazawa, M.; Negishi, Y.

    1986-08-01

    The limit of repeater spacing is investigated theoretically for optical transmission lines utilizing stimulated Raman scattering to amplify the signal light. Achievable repeater spacing is numerically estimated on the basis of coupled power equations and measured fiber characteristics for various signal wavelengths and relative index differences. Three types of transmission line configurations are considered, i.e., utilization of forward only, backward only, and bidirectional amplification. In the third case, a transmission distance of more than 400 km is predicted for an input signal light power of 100 microW, a signal wavelength of 1.57 microns, and a pump power of 0.5 W using a fiber with a relative index difference of 1 percent for signal light amplification.

  3. Suzaku observation of the new Soft Gamma Repeater SGR 0501+4516 in outburst

    NARCIS (Netherlands)

    T. Enoto; Y.E. Nakagawa; N. Rea; P. Esposito; D. Götz; K. Hurley; G.L. Israel; M. Kokubun; K. Makishima; S. Mereghetti; H. Murakami; K. Nakazawa; T. Sakamoto; L. Stella; A. Tiengo; R. Turolla; S. Yamada; K. Yamaoka; A. Yoshida; S. Zane

    2009-01-01

    We present the first Suzaku observation of the new Soft Gamma Repeater, SGR 0501+4516, performed on 2008 August 26, four days after the onset of bursting activity of this new member of the magnetar family. The soft X-ray persistent emission was detected with the X-ray Imaging Spectrometer (XIS) at a

  4. Multiwavelength Observations of the Soft Gamma Repeater SGR 1900+14 during Its 2001 April Activation

    NARCIS (Netherlands)

    C. Kouveliotou; A. Tennant; P.M. Woods; M.C. Weisskopf; K. Hurley; R.P. Fender; S.T. Garrington; S.K. Patel; E. Göğüş

    2001-01-01

    The soft gamma repeater SGR 1900+14 became active on 2001 April 18 after about 2 years of quiescence; it had remained at a very low state of activity since the fall of 1998, when it exhibited extraordinary flaring. We have observed the source in the gamma-rays and X-rays with Ulysses and Chandra and

  5. A longitudinal Model for repeated interval-observed data with informative dropouts.

    Science.gov (United States)

    Chen, Huichao; Manatunga, Amita K

    2011-02-01

    We consider repeated measures interval-observed data with informative dropouts. We model the repeated outcomes via an unobserved random intercept and it is assumed that the probability of dropout during the study period is linearly related to the random intercept in a complementary log-log scale. Assuming the random effect follows the power variance function (PVF) family suggested by Hougaard (2000), we derive the marginal likelihood in a closed form. We evaluate the performance of the maximum likelihood estimation via simulation studies and apply the proposed method to a real data set.

  6. Marked variation in predicted and observed variability of tandem repeat loci across the human genome

    Directory of Open Access Journals (Sweden)

    Shields Denis C

    2008-04-01

    Full Text Available Abstract Background Tandem repeat (TR variants in the human genome play key roles in a number of diseases. However, current models predicting variability are based on limited training sets. We conducted a systematic analysis of TRs of unit lengths 2–12 nucleotides in Whole Genome Shotgun (WGS sequences to define the extent of variation of 209,214 unique repeat loci throughout the genome. Results We applied a multivariate statistical model to predict TR variability. Predicted heterozygosity correlated with heterozygosity in the CEPH polymorphism database (correlation ρ = 0.29, p Conclusion Variability among 2–12-mer TRs in the genome can be modeled by a few parameters, which do not markedly differ according to unit length, consistent with a common mechanism for the generation of variability among such TRs. Analysis of the distributions of observed and predicted variants across the genome showed a general concordance, indicating that the repeat variation dataset does not exhibit strong regional ascertainment biases. This revealed a deficit of variant repeats in chromosomes 19 and Y – likely to reflect a reduction in 2-mer repeats in the former and a reduced level of recombination in the latter – and excesses in chromosomes 6, 13, 20 and 21.

  7. Observation of the Earth system from space

    CERN Document Server

    Flury, Jakob; Reigber, Christoph; Rothacher, Markus; Boedecker, Gerd

    2006-01-01

    In the recent years, space-based observation methods have led to a subst- tially improved understanding of Earth system. Geodesy and geophysics are contributing to this development by measuring the temporal and spatial va- ations of the Earth's shape, gravity ?eld, and magnetic ?eld, as well as at- sphere density. In the frame of the GermanR&D programmeGEOTECHNO- LOGIEN,researchprojectshavebeen launchedin2002relatedto the satellite missions CHAMP, GRACE and ESA's planned mission GOCE, to comp- mentary terrestrial and airborne sensor systems and to consistent and stable high-precision global reference systems for satellite and other techniques. In the initial 3-year phase of the research programme (2002-2004), new gravity ?eld models have been computed from CHAMP and GRACE data which outperform previous models in accuracy by up to two orders of m- nitude for the long and medium wavelengths. A special highlight is the - termination of seasonal gravity variations caused by changes in continental water masses...

  8. Long-term clinical, microbiological, and immunological observations of a volunteer repeatedly infected with Chlamydia trachomatis.

    OpenAIRE

    Hanna, L; Jawetz, E; Dawson, C R; Thygeson, P

    1982-01-01

    A blind volunteer was inoculated in one eye with an isolate of Chlamydia trachomatis in 1961 and followed for 20 years. During this time, many observations were made of his clinical responses to the first inoculation and several subsequent inoculations with the same and other strains, chlamydial shedding, and antibody and cell-mediated immune responses. Evidence is presented that partial resistance to chlamydial eye infection developed during repeated infections and that antibodies, cell-medi...

  9. Future Observations of White Dwarfs from Space

    Science.gov (United States)

    Barstow, M. A.; Casewell, S. L.

    2015-06-01

    We outline two possible future space missions suitable for the study of white dwarfs. These lie at the extreme ends of the spectrum of such opportunities in terms of cost and timescale. The SIRIUS extreme ultraviolet spectrograph will be proposed for the ESA/Chinese Academy of Sciences small, ≍ 50M Euro, mission. If selected it will fly in 2021. ATLAST is planned to be a very large UVOIR space observatory to provide a true replacement for the capabilities of HST. If it goes ahead, it will be a several billion-dollar project and will not fly before 2030. The paper provides further details on the technical capabilities of these space telescopes.

  10. Experimental Observations of Ion Phase-Space Vortices

    DEFF Research Database (Denmark)

    Pécseli, Hans; Armstrong, R. J.; Trulsen, J.

    1981-01-01

    Experimental observations of ion phase-space vortices are reported. The ion phase-space vortices form in the region of heated ions behind electrostatic ion acoustic shocks. The results are in qualitative agreement with numerical and analytic studies....

  11. Stennis Space Center observes Disability Awareness Day

    Science.gov (United States)

    2009-01-01

    Members of STARC, a non-profit organization in Slidell, La., that seeks to help people with disabilities lead meaningful, productive lives, pose with their appreciation awards during Disability Awareness Day at Stennis Space Center on Oct. 15. The group members received appreciation awards for their dedicated service to the rocket engine testing facility. Disability Awareness Day was hosted by the Stennis Diversity Council and included guest speakers from several area agencies.

  12. Stennis Space Center observes Disability Awareness Day

    Science.gov (United States)

    2009-01-01

    Members of STARC, a non-profit organization in Slidell, La., that seeks to help people with disabilities lead meaningful, productive lives, pose with their appreciation awards during Disability Awareness Day at Stennis Space Center on Oct. 15. The group members received appreciation awards for their dedicated service to the rocket engine testing facility. Disability Awareness Day was hosted by the Stennis Diversity Council and included guest speakers from several area agencies.

  13. Seismicity along the Main Marmara Fault, Turkey: from space-time distribution to repeating events

    Science.gov (United States)

    Schmittbuhl, Jean; Karabulut, Hayrullah; Lengliné, Olivier; Bouchon, Michel

    2016-04-01

    The North Anatolian Fault (NAF) poses a significant hazard for the large cities surrounding the Marmara Sea region particularly the megalopolis of Istanbul. Indeed, the NAF is presently hosting a long unruptured segment below the Sea of Marmara. This seismic gap is approximately 150 km long and corresponds to the Main Marmara Fault (MMF). The seismicity along the Main Marmara Fault (MMF) below the Marmara Sea is analyzed here during the 2007-2012 period to provide insights on the recent evolution of this important regional seismic gap. High precision locations show that seismicity is strongly varying along strike and depth providing fine details of the fault behavior that are inaccessible from geodetic inversions. The activity strongly clusters at the regions of transition between basins. The Central basin shows significant seismicity located below the shallow locking depth inferred from GPS measurements. Its b-value is low and the average seismic slip is high. Interestingly we found also several long term repeating earthquakes in this domain. Using a template matching technique, we evidenced two new families of repeaters: a first family that typically belongs to aftershock sequences and a second family of long lasting repeaters with a multi-month recurrence period. All observations are consistent with a deep creep of this segment. On the contrary, the Kumburgaz basin at the center of the fault shows sparse seismicity with the hallmarks of a locked segment. In the eastern Marmara Sea, the seismicity distribution along the Princes Island segment in the Cinarcik basin, is consistent with the geodetic locking depth of 10km and a low contribution to the regional seismic energy release. The assessment of the locked segment areas provide an estimate of the magnitude of the main forthcoming event to be about 7.3 assuming that the rupture will not enter significantly within creeping domains.

  14. Earth Observation from Space: Competition or Cooperation?

    Science.gov (United States)

    1992-04-01

    begin in earnest in April of 1960 with the launch of TIPOS (Television and Infrared Observation Satellite) which observed weather patterns in the United...data became a candidate for entry into the commercial sector where there appeared to be an imagery market . Responsibility for system operations was...it has not been fully developed. The slow emergence of remote sensing as a commercial enterprise has been attributed to two factors; 1) poor market

  15. Tropospheric Composition Change observed from Space (Invited)

    Science.gov (United States)

    Richter, A.; Hilboll, A.; Leitao, J.; Vrekoussis, M.; Wittrock, F.; Burrows, J. P.

    2010-12-01

    The composition of the troposphere is largely influenced by surface emissions of both natural and anthropogenic origins. These emissions change over time as result of human activities and natural variability, leading to varying atmospheric levels of primary and secondary pollutants. Satellite observations of sun light scattered back by the surface and the atmosphere can be used to retrieve information on atmospheric trace gases by application of optical absorption spectroscopy. In the UV and visible part of the spectrum, these measurements have good sensitivity to the lower troposphere providing information on relevant species such as O3, NO2, SO2, HCHO or glyoxal. Here, we report on recent results on tropospheric composition changes obtained from the GOME, SCIAMACHY and GOME-2 instruments which have a combined data record of nearly 15 years. The focus is on NO2 which shows an increasing trend over Asia and many large cities in countries with growing economies. At the same time, significant reductions are observed over the US and Europe, probably as result of changes in environmental legislation. SO2 signals have been decreasing over the US since 1996 while a strong upward trend was evident over China until recently when desulphurisation of power plant emissions came into effect. There also is evidence for increases in VOC levels over China which could be either of anthropogenic origin or from biogenic emissions.

  16. Multiwavelength Observations of the Soft Gamma Repeater SGR 1900+14 During Its 2001 April Activation

    Science.gov (United States)

    Kouveliotou, C.; Tennant, A.; Woods, P. M.; Weisskopf, M. C.; Hurley, K.; Fender, R. P.; Garrington, S. T.; Patel, S. K.; Goegues, E.

    2001-01-01

    The soft gamma repeater SGR 1900+14 became active on 2001 April 18 after about two years of quiescence; it had remained at a very low state of activity since the fall of 1998, when it exhibited extraordinary flaring. We have observed the source in the gamma-rays and X-rays with Ulysses and Chandra and in the radio with MERLIN. We report here the confirmation of a two-component X-ray spectrum (power law and blackbody), indicating emission from the neutron star surface. We have determined that there is a dust halo, due to scattering in the interstellar medium, surrounding the source that extends up to approximately 100 arcsec from the center of SGR 1900+14.

  17. The repeating Fast Radio Burst FRB 121102: Multi-wavelength observations and additional bursts

    CERN Document Server

    Scholz, P; Hessels, J W T; Chatterjee, S; Cordes, J M; Kaspi, V M; Wharton, R S; Bassa, C G; Bogdanov, S; Camilo, F; Crawford, F; Deneva, J; van Leeuwen, J; Lynch, R; Madsen, E C; McLaughlin, M A; Mickaliger, M; Parent, E; Patel, C; Ransom, S M; Seymour, A; Stairs, I H; Stappers, B W; Tendulkar, S P

    2016-01-01

    We report on radio and X-ray observations of the only known repeating Fast Radio Burst (FRB) source, FRB 121102. We have detected six additional radio bursts from this source: five with the Green Bank Telescope at 2 GHz, and one at 1.4 GHz at the Arecibo Observatory for a total of 17 bursts from this source. All have dispersion measures consistent with a single value ($\\sim559$ pc cm$^{-3}$) that is three times the predicted maximum Galactic value. The 2-GHz bursts have highly variable spectra like those at 1.4 GHz, indicating that the frequency structure seen across the individual 1.4 and 2-GHz bandpasses is part of a wideband process. X-ray observations of the FRB 121102 field with the Swift and Chandra observatories show at least one possible counterpart; however, the probability of chance superposition is high. A radio imaging observation of the field with the Jansky Very Large Array at 1.6 GHz yields a 5$\\sigma$ upper limit of 0.3 mJy on any point-source continuum emission. This upper limit, combined wit...

  18. Space Weather Monitoring for ISS Space Environments Engineering and Crew Auroral Observations

    Science.gov (United States)

    Minow, Joseph; Pettit, Donald R.; Hartman, William A.

    2012-01-01

    Today s presentation describes how real time space weather data is used by the International Space Station (ISS) space environments team to obtain data on auroral charging of the ISS vehicle and support ISS crew efforts to obtain auroral images from orbit. Topics covered include: Floating Potential Measurement Unit (FPMU), . Auroral charging of ISS, . Real ]time space weather monitoring resources, . Examples of ISS auroral charging captured from space weather events, . ISS crew observations of aurora.

  19. Mirror neurons in monkey area F5 do not adapt to the observation of repeated actions.

    Science.gov (United States)

    Caggiano, Vittorio; Pomper, Joern K; Fleischer, Falk; Fogassi, Leonardo; Giese, Martin; Thier, Peter

    2013-01-01

    Repetitive presentation of the same visual stimulus entails a response decrease in the action potential discharge of neurons in various areas of the monkey visual cortex. It is still unclear whether this repetition suppression effect is also present in single neurons in cortical premotor areas responding to visual stimuli, as suggested by the human functional magnetic resonance imaging literature. Here we report the responses of 'mirror neurons' in monkey area F5 to the repeated presentation of action movies. We find that most single neurons and the population at large do not show a significant decrease of the firing rate. On the other hand, simultaneously recorded local field potentials exhibit repetition suppression. As local field potentials are believed to be better linked to the blood-oxygen-level-dependent (BOLD) signal exploited by functional magnetic resonance imaging, these findings suggest caution when trying to derive conclusions on the spiking activity of neurons in a given area based on the observation of BOLD repetition suppression.

  20. Dynamic in situ observation of voltage-driven repeatable magnetization reversal at room temperature

    Science.gov (United States)

    Gao, Ya; Hu, Jia-Mian; Nelson, C. T.; Yang, T. N.; Shen, Y.; Chen, L. Q.; Ramesh, R.; Nan, C. W.

    2016-03-01

    Purely voltage-driven, repeatable magnetization reversal provides a tantalizing potential for the development of spintronic devices with a minimum amount of power consumption. Substantial progress has been made in this subject especially on magnetic/ferroelectric heterostructures. Here, we report the in situ observation of such phenomenon in a NiFe thin film grown directly on a rhombohedral Pb(Mg1/3Nb2/3)0.7Ti0.3O3(PMN-PT) ferroelectric crystal. Under a cyclic voltage applied perpendicular to the PMN-PT without a magnetic field, the local magnetization of NiFe can be repetitively reversed through an out-of-plane excursion and then back into the plane. Using phase field simulations we interpret magnetization reversal as a synergistic effect of the metastable ferroelastic switching in the PMN-PT and an electrically rotatable local exchange bias field arising from the heterogeneously distributed NiO clusters at the interface.

  1. The Platform Design of Space-based Optical Observations of Space Debris

    Science.gov (United States)

    Bing-er, Chen; Jian-ning, Xiong

    2017-01-01

    The basic method to design a platform for the space-based optical observations of space debris is introduced. The observation schemes of GEO (geosynchronous equatorial orbit) and LEO (low Earth orbit) debris are given respectively, including the orbital parameters of platforms and the pointing of telescopes, etc. The debris studied here are all taken from the foreign catalog. According to the real orbits of space debris, the observational results of different schemes are simulated. By studying the single platform, the optimal observing altitude for the GEO debris and the optimal telescope's deflection angles at different altitudes for the LEO debris are given. According to these, the multi-platform observation networks are designed. By analyzing the advantages and disadvantages of different schemes, it can provide a reference for the application of space-based optical observations of space debris

  2. Comments on Current Space Systems Observing the Climate

    Science.gov (United States)

    Fisk, L. A.

    2016-07-01

    The Global Climate Observing System (GCOS), which was established in 1992, has been effective in specifying the observations needed for climate studies, and advocating that these observations be made. As a result, there are essential climate variables being observed, particularly from space, and these have formed the basis for our ever-improving models of how the Earth system functions and the human impact on it. We cannot conclude, however, that the current observing system in space is adequate. Climate change is accelerating, and we need to ensure that our observations capture, with completeness and with proper resolution and cadence, the most important changes. Perhaps of most significance, we need to use observations from space to guide the mitigation and adaptation strategies on which at last our civilization seems prepared to embark. And we need to use our observations to educate particularly policy makers on the reality of climate change, so that none deny the need to act. COSPAR is determined to play its part in highlighting the need to strengthen the climate observing system and notably its research component. This is being accomplished through events like the present roundtable, through the work of its Scientific Commission A, its Task Group on GEO (where COSPAR is serving as a member of its Program Board), and by promoting among space agencies and policy-makers the recently released scientific roadmap on Integrated Earth System Science for the period 2016-2025.

  3. A Dynamic Earth: 50 Years of Observations from Space

    Science.gov (United States)

    Evans, Cynthia A.

    2013-01-01

    Observations of the surface of the Earth began more than a half century ago with the earliest space missions. The global geopolitical environment at the beginning of the space age fueled advances in rocketry and human exploration, but also advances in remote sensing. At the same time that space-based Earth Observations were developing, global investments in infrastructure that were initiated after World War II accelerated large projects such as the construction of highways, the expansion of cities and suburbs, the damming of rivers, and the growth of big agriculture. These developments have transformed the Earth s surface at unprecedented rates. Today, we have a remarkable library of 50 years of observations of the Earth taken by satellite-based sensors and astronauts, and these images and observations provide insight into the workings of the Earth as a system. In addition, these observations record the footprints of human activities around the world, and illustrate how our activities contribute to the changing face of the Earth. Starting with the iconic "Blue Marble" image of the whole Earth taken by Apollo astronauts, we will review a timeline of observations of our planet as viewed from space.

  4. A preliminary estimate of geoid-induced variations in repeat orbit satellite altimeter observations

    Science.gov (United States)

    Brenner, Anita C.; Beckley, B. D.; Koblinsky, C. J.

    1990-01-01

    Altimeter satellites are often maintained in a repeating orbit to facilitate the separation of sea-height variations from the geoid. However, atmospheric drag and solar radiation pressure cause a satellite orbit to drift. For Geosat this drift causes the ground track to vary by + or - 1 km about the nominal repeat path. This misalignment leads to an error in the estimates of sea surface height variations because of the local slope in the geoid. This error has been estimated globally for the Geosat Exact Repeat Mission using a mean sea surface constructed from Geos 3 and Seasat altimeter data. Over most of the ocean the geoid gradient is small, and the repeat-track misalignment leads to errors of only 1 to 2 cm. However, in the vicinity of trenches, continental shelves, islands, and seamounts, errors can exceed 20 cm. The estimated error is compared with direct estimates from Geosat altimetry, and a strong correlation is found in the vicinity of the Tonga and Aleutian trenches. This correlation increases as the orbit error is reduced because of the increased signal-to-noise ratio.

  5. A preliminary estimate of geoid-induced variations in repeat orbit satellite altimeter observations

    Science.gov (United States)

    Brenner, Anita C.; Beckley, B. D.; Koblinsky, C. J.

    1990-01-01

    Altimeter satellites are often maintained in a repeating orbit to facilitate the separation of sea-height variations from the geoid. However, atmospheric drag and solar radiation pressure cause a satellite orbit to drift. For Geosat this drift causes the ground track to vary by + or - 1 km about the nominal repeat path. This misalignment leads to an error in the estimates of sea surface height variations because of the local slope in the geoid. This error has been estimated globally for the Geosat Exact Repeat Mission using a mean sea surface constructed from Geos 3 and Seasat altimeter data. Over most of the ocean the geoid gradient is small, and the repeat-track misalignment leads to errors of only 1 to 2 cm. However, in the vicinity of trenches, continental shelves, islands, and seamounts, errors can exceed 20 cm. The estimated error is compared with direct estimates from Geosat altimetry, and a strong correlation is found in the vicinity of the Tonga and Aleutian trenches. This correlation increases as the orbit error is reduced because of the increased signal-to-noise ratio.

  6. Improvements in Anatomy Knowledge When Utilizing a Novel Cyclical "Observe-Reflect-Draw-Edit-Repeat" Learning Process

    Science.gov (United States)

    Backhouse, Mark; Fitzpatrick, Michael; Hutchinson, Joseph; Thandi, Charankumal S.; Keenan, Iain D.

    2017-01-01

    Innovative educational strategies can provide variety and enhance student learning while addressing complex logistical and financial issues facing modern anatomy education. "Observe-Reflect-Draw-Edit-Repeat" (ORDER), a novel cyclical artistic process, has been designed based on cognitivist and constructivist learning theories, and on…

  7. Improvements in Anatomy Knowledge When Utilizing a Novel Cyclical "Observe-Reflect-Draw-Edit-Repeat" Learning Process

    Science.gov (United States)

    Backhouse, Mark; Fitzpatrick, Michael; Hutchinson, Joseph; Thandi, Charankumal S.; Keenan, Iain D.

    2017-01-01

    Innovative educational strategies can provide variety and enhance student learning while addressing complex logistical and financial issues facing modern anatomy education. "Observe-Reflect-Draw-Edit-Repeat" (ORDER), a novel cyclical artistic process, has been designed based on cognitivist and constructivist learning theories, and on…

  8. ESA takes part in Earth observation and space science experiments on board the Space Shuttle

    Science.gov (United States)

    1993-03-01

    The ATLAS-2 mission is focusing on Earth observation and space science; three out of the seven instruments have been developed by scientific institutes in Belgium, France and Germany, with support from ESA. Four experiments have been provided by NASA and US scientists. The three European instruments have already shown an excellent performance during the first Atlas mission in March 1992, when they were tended by payload specialist Dirk Frimout, a Belgian astronaut and ESA staff member. Although the main scientific objective of the series of Atlas missions is to achieve continuity of annual measurements over a period as long as a decade, the first scientific results from Atlas can already be considered as a contribution to critical research topics, in particular the environment. The data from ATLAS-2 will add to this achievement. Two European instruments, Solcon and Solspec, are measuring to a very high degree of precision the total irradiation the Earth receives from the Sun - the "solar constant" -and the spectral distribution of this radiation over a wide range of wavelengths. Knowledge of the solar constant and the solar radiation spectrum matters not only for a better understanding of the Sun, but also for improving numerical models of climate and climate change. SOLCON was developed under the responsibility of Dr. Dominique Crommelynck of the Royal Meteorological Institute of Brussels, Belgium. SOLSPEC was instead developed under the responsibility of Dr. Gerard Thuillier of the CNRS, Verrieres le Buisson, France. One of these instruments will be fully remote-controlled by scientists from a laboratory in Belgium, via telecommunications links to the Shuttle, and the data of another will be transmitted to Belgium in real time to follow the results obtained. This approach is known as telescience: using telescience, a scientist can monitor his experiment in real-time, repeat it with different settings, consult his team, process data and adapt his measurements when

  9. Earth Observation from Space - The Issue of Environmental Sustainability

    Science.gov (United States)

    Durrieu, Sylvie; Nelson, Ross F.

    2013-01-01

    Remote sensing scientists work under assumptions that should not be taken for granted and should, therefore, be challenged. These assumptions include the following: 1. Space, especially Low Earth Orbit (LEO), will always be available to governmental and commercial space entities that launch Earth remote sensing missions. 2. Space launches are benign with respect to environmental impacts. 3. Minimization of Type 1 error, which provides increased confidence in the experimental outcome, is the best way to assess the significance of environmental change. 4. Large-area remote sensing investigations, i.e. national, continental, global studies, are best done from space. 5. National space missions should trump international, cooperative space missions to ensure national control and distribution of the data products. At best, all of these points are arguable, and in some cases, they're wrong. Development of observational space systems that are compatible with sustainability principles should be a primary concern when Earth remote sensing space systems are envisioned, designed, and launched. The discussion is based on the hypothesis that reducing the environmental impacts of thedata acquisition step,which is at the very beginning of the information streamleading to decision and action, will enhance coherence in the information streamand strengthen the capacity of measurement processes to meet their stated functional goal, i.e. sustainable management of Earth resources. We suggest that unconventional points of view should be adopted and when appropriate, remedial measures considered that could help to reduce the environmental footprint of space remote sensing and of Earth observation and monitoring systems in general. This article discusses these five assumptions inthe contextof sustainablemanagementof Earth's resources. Takingeachassumptioninturn,we find the following: (1) Space debris may limit access to Low Earth Orbit over the next decades. (2) Relatively speaking, given

  10. Repeatability of Cone Spacing Measures in Eyes With Inherited Retinal Degenerations

    National Research Council Canada - National Science Library

    Zayit-Soudry, Shiri; Sippl-Swezey, Nicolas; Porco, Travis C; Lynch, Stephanie K; Syed, Reema; Ratnam, Kavitha; Menghini, Moreno; Roorda, Austin J; Duncan, Jacque L

    2015-01-01

    ...)-derived cone spacing measures in eyes with inherited retinal degenerations (IRD) and in normal eyes. Twenty IRD patients and 10 visually normal subjects underwent AOSLO imaging at two visits separated by no more than 1 month...

  11. PHYSICAL CONCEPT APPLIED TO SPACE OBSERVATION BY LANDASAT 7 TM

    Directory of Open Access Journals (Sweden)

    C TOUMIAT

    2015-06-01

    Full Text Available Physical concept has been applied to space observation by using images and data of LANDASAT 7 in order to  to extract quantitative information  about the studied areas facilitate . The final product should respect a norm in presenting a list of physical indicators or minimal reference classes.

  12. Improved Space Object Observation Techniques Using CMOS Detectors

    Science.gov (United States)

    Schildknecht, T.; Hinze, A.; Schlatter, P.; Silha, J.; Peltonen, J.; Santti, T.; Flohrer, T.

    2013-08-01

    CMOS-sensors, or in general Active Pixel Sensors (APS), are rapidly replacing CCDs in the consumer camera market. Due to significant technological advances during the past years these devices start to compete with CCDs also for demanding scientific imaging applications, in particular in the astronomy community. CMOS detectors offer a series of inherent advantages compared to CCDs, due to the structure of their basic pixel cells, which each contain their own amplifier and readout electronics. The most prominent advantages for space object observations are the extremely fast and flexible readout capabilities, feasibility for electronic shuttering and precise epoch registration, and the potential to perform image processing operations on-chip and in real-time. Presently applied and proposed optical observation strategies for space debris surveys and space surveillance applications had to be analyzed. The major design drivers were identified and potential benefits from using available and future CMOS sensors were assessed. The major challenges and design drivers for ground-based and space-based optical observation strategies have been analyzed. CMOS detector characteristics were critically evaluated and compared with the established CCD technology, especially with respect to the above mentioned observations. Similarly, the desirable on-chip processing functionalities which would further enhance the object detection and image segmentation were identified. Finally, the characteristics of a particular CMOS sensor available at the Zimmerwald observatory were analyzed by performing laboratory test measurements.

  13. High-precision repeat-groundtrack orbit design and maintenance for Earth observation missions

    Science.gov (United States)

    He, Yanchao; Xu, Ming; Jia, Xianghua; Armellin, Roberto

    2017-02-01

    The focus of this paper is the design and station keeping of repeat-groundtrack orbits for Sun-synchronous satellites. A method to compute the semimajor axis of the orbit is presented together with a station-keeping strategy to compensate for the perturbation due to the atmospheric drag. The results show that the nodal period converges gradually with the increase of the order used in the zonal perturbations up to J_{15} . A differential correction algorithm is performed to obtain the nominal semimajor axis of the reference orbit from the inputs of the desired nodal period, eccentricity, inclination and argument of perigee. To keep the satellite in the proximity of the repeat-groundtrack condition, a practical orbit maintenance strategy is proposed in the presence of errors in the orbital measurements and control, as well as in the estimation of the semimajor axis decay rate. The performance of the maintenance strategy is assessed via the Monte Carlo simulation and the validation in a high fidelity model. Numerical simulations substantiate the validity of proposed mean-elements-based orbit maintenance strategy for repeat-groundtrack orbits.

  14. High-precision repeat-groundtrack orbit design and maintenance for Earth observation missions

    Science.gov (United States)

    He, Yanchao; Xu, Ming; Jia, Xianghua; Armellin, Roberto

    2017-06-01

    The focus of this paper is the design and station keeping of repeat-groundtrack orbits for Sun-synchronous satellites. A method to compute the semimajor axis of the orbit is presented together with a station-keeping strategy to compensate for the perturbation due to the atmospheric drag. The results show that the nodal period converges gradually with the increase of the order used in the zonal perturbations up to J_{15}. A differential correction algorithm is performed to obtain the nominal semimajor axis of the reference orbit from the inputs of the desired nodal period, eccentricity, inclination and argument of perigee. To keep the satellite in the proximity of the repeat-groundtrack condition, a practical orbit maintenance strategy is proposed in the presence of errors in the orbital measurements and control, as well as in the estimation of the semimajor axis decay rate. The performance of the maintenance strategy is assessed via the Monte Carlo simulation and the validation in a high fidelity model. Numerical simulations substantiate the validity of proposed mean-elements-based orbit maintenance strategy for repeat-groundtrack orbits.

  15. Observing supernova 1987A with the refurbished Hubble Space Telescope.

    Science.gov (United States)

    France, Kevin; McCray, Richard; Heng, Kevin; Kirshner, Robert P; Challis, Peter; Bouchet, Patrice; Crotts, Arlin; Dwek, Eli; Fransson, Claes; Garnavich, Peter M; Larsson, Josefin; Lawrence, Stephen S; Lundqvist, Peter; Panagia, Nino; Pun, Chun S J; Smith, Nathan; Sollerman, Jesper; Sonneborn, George; Stocke, John T; Wang, Lifan; Wheeler, J Craig

    2010-09-24

    Observations with the Hubble Space Telescope (HST), conducted since 1990, now offer an unprecedented glimpse into fast astrophysical shocks in the young remnant of supernova 1987A. Comparing observations taken in 2010 with the use of the refurbished instruments on HST with data taken in 2004, just before the Space Telescope Imaging Spectrograph failed, we find that the Lyα and Hα lines from shock emission continue to brighten, whereas their maximum velocities continue to decrease. We observe broad, blueshifted Lyα, which we attribute to resonant scattering of photons emitted from hot spots on the equatorial ring. We also detect N v λλ1239, 1243 angstrom line emission, but only to the red of Lyα. The profiles of the N v lines differ markedly from that of Hα, suggesting that the N4+ ions are scattered and accelerated by turbulent electromagnetic fields that isotropize the ions in the collisionless shock.

  16. Observing Supernova 1987A with the Refurbished Hubble Space Telescope

    CERN Document Server

    France, Kevin; Heng, Kevin; Kirshner, Robert; Challis, Peter; Bouchet, Patrice; Crotts, Arlin; Dwek, Eli; Fransson, Claes; Garnavich, Peter; Larsson, Josefin; Lawrence, Stephen; Lundqvist, Peter; Panagia, Nino; Pun, Chun; Smith, Nathan; Sollerman, Jesper; Sonneborn, George; Stocke, John; Wang, Lifan; Wheeler, Craig

    2010-01-01

    Observations with the Hubble Space Telescope (HST), conducted since 1990, now offer an unprecedented glimpse into fast astrophysical shocks in the young remnant of supernova 1987A. Comparing observations taken in 2010 using the refurbished instruments on HST with data taken in 2004, just before the Space Telescope Imaging Spectrograph failed, we find that the Ly-a and H-a lines from shock emission continue to brighten, while their maximum velocities continue to decrease. We observe broad blueshifted Ly-a, which we attribute to resonant scattering of photons emitted from hotspots on the equatorial ring. We also detect NV~\\lambda\\lambda 1239,1243 A line emission, but only to the red of Ly-A. The profiles of the NV lines differ markedly from that of H-a, suggesting that the N^{4+} ions are scattered and accelerated by turbulent electromagnetic fields that isotropize the ions in the collisionless shock.

  17. Astronomical Observations Astronomy and the Study of Deep Space

    CERN Document Server

    2010-01-01

    Our Search for knowledge about the universe has been remarkable, heartbreaking, fantastical, and inspiring, and this search is just beginning. Astronomical Observations is part of a 7 book series that takes readers through a virtual time warp of our discovery. From the nascent space programs of the 1960's to today's space tourism and the promise of distant planet colonization, readers will be transfixed. Throughout this journey of the mind, Earth-bound explorers gain keen insight into the celestial phenomena that have fascinated humans for centuries. Thrilling narratives about indefatigable sc

  18. Technique for observation derived boundary conditions for Space Weather

    Science.gov (United States)

    Pagano, Paolo; Mackay, Duncan; Yeates, Anthony

    2017-04-01

    We propose a new efficient and accurate modelling technique suitable for the next generation of Space Weather predictive tools. Specifically, we put forward an approach that can provide interplanetary Space Weather forecasting models with an accurate time dependent boundary condition of erupting flux ropes in the upper Solar Corona. The unique strength of this technique is that it follows the time evolution of coronal magnetic fields directly driven from observations and captures the full life span of magnetic flux ropes from formation to ejection. To produce accurate and effective boundary conditions we couple two different modelling techniques, MHD simulations with quasi-static non-potential modelling. Our modelling approach uses a time series of observed synoptic magnetograms to drive the non-potential evolution model of the coronal magnetic field to follow the formation and loss of equilibrium of magnetic flux ropes. Following this a MHD simulation captures the dynamic evolution of the ejection phase of the flux rope into interplanetary space. We focus here on the MHD simulation that describes the ejection of two magnetic flux ropes through the solar corona to the outer boundary. At this boundary we then produce time dependent boundary conditions for the magnetic field and plasma that in the future may be applied to interplanetary space weather prediction models. We illustrate that the coupling of observationally derived quasi-static non-potential magnetic field modelling and MHD simulations can significantly reduce the computational time for producing realistic observationally derived boundary conditions at the boundary between the corona and interplanetary space.

  19. Observing the solid Earth, oceans and land waters from space

    Directory of Open Access Journals (Sweden)

    Cazenave A.

    2009-02-01

    Full Text Available In this article, we present a number of significant results related to the solid Earth and its fluid envelopes obtained in the recent years/decades using remote sensing techniques. We first discuss measurements of the Earth gravity field at different spatial scales and the recovery of seafloor topography from satellite altimetry. We briefly mention precise positioning results based on GPS and other space techniques, and applications to tectonic motions and crustal deformations. Next we discuss recent advances in ocean dynamics based on high-precision satellite altimetry missions, and focus on sea level rise. We also discuss how remote sensing techniques, including space gravimetry, inform on the mass balance of the ice sheets and corresponding contribution to sea level rise. As a final example, we report on the monitoring of surface water levels (lakes, rivers, floodplains by satellite altimetry and on total land water storage change at river basin scale, using space gravimetry observations.

  20. Observables and density matrices embedded in dual Hilbert spaces

    Science.gov (United States)

    Prosen, T.; Martignon, L.; Seligman, T. H.

    2015-06-01

    The introduction of operator states and of observables in various fields of quantum physics has raised questions about the mathematical structures of the corresponding spaces. In the framework of third quantization it had been conjectured that we deal with Hilbert spaces although the mathematical background was not entirely clear, particularly, when dealing with bosonic operators. This in turn caused some doubts about the correct way to combine bosonic and fermionic operators or, in other words, regular and Grassmann variables. In this paper we present a formal answer to the problems on a simple and very general basis. We illustrate the resulting construction by revisiting the Bargmann transform and finding the known connection between {{L}}2({{R}}) and the Bargmann-Hilbert space. We pursue this line of thinking one step further and discuss the representations of complex extensions of linear canonical transformations as isometries between dual Hilbert spaces. We then use the formalism to give an explicit formulation for Fock spaces involving both fermions and bosons thus solving the problem at the origin of our considerations.

  1. Observing terrestrial ecosystems and the carbon cycle from space

    Energy Technology Data Exchange (ETDEWEB)

    Schimel, David [Jet Propulsion Laboratory, California Institute of Technology, Pasadena CA 91101 USA; Pavlick, Ryan [Jet Propulsion Laboratory, California Institute of Technology, Pasadena CA 91101 USA; Fisher, Joshua B. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena CA 91101 USA; Asner, Gregory P. [Department of Global Ecology, Carnegie Institution for Science, 260 Panama St. Stanford CA 94305 USA; Saatchi, Sassan [Jet Propulsion Laboratory, California Institute of Technology, Pasadena CA 91101 USA; Townsend, Philip [University of Wisconsin-Madison, Madison WI 53706 USA; Miller, Charles [Jet Propulsion Laboratory, California Institute of Technology, Pasadena CA 91101 USA; Frankenberg, Christian [Jet Propulsion Laboratory, California Institute of Technology, Pasadena CA 91101 USA; Hibbard, Kathy [Pacific Northwest National Laboratory, PO Box 999 MSIN: K9-34 Richland WA 99352 USA; Cox, Peter [College of Engineering, Mathematics and Physical Sciences, University of Exeter, North Park Road Streatham Campus Harrison Building Exeter EX4 4QF UK

    2015-02-06

    Modeled terrestrial ecosystem and carbon cycle feedbacks contribute substantial uncertainty to projections of future climate. The limitations of current observing networks contribute to this uncertainty. Here we present a current climatology of global model predictions and observations for photosynthesis, biomass, plant diversity and plant functional diversity. Carbon cycle tipping points occur in terrestrial regions where fluxes or stocks are largest, and where biological variability is highest, the tropics and Arctic/Boreal zones. Global observations are predominately in the mid-latitudes and are sparse in high and low latitude ecosystems. Observing and forecasting ecosystem change requires sustained observations of sufficient density in time and space in critical regions. Using data and theory available now, we can develop a strategy to detect and forecast terrestrial carbon cycle-climate interactions, by combining in situ and remote techniques.

  2. Methane hydrate distribution from prolonged and repeated formation in natural and compacted sand samples: X-ray CT observations

    Energy Technology Data Exchange (ETDEWEB)

    Rees, E.V.L.; Kneafsey, T.J.; Seol, Y.

    2010-07-01

    To study physical properties of methane gas hydrate-bearing sediments, it is necessary to synthesize laboratory samples due to the limited availability of cores from natural deposits. X-ray computed tomography (CT) and other observations have shown gas hydrate to occur in a number of morphologies over a variety of sediment types. To aid in understanding formation and growth patterns of hydrate in sediments, methane hydrate was repeatedly formed in laboratory-packed sand samples and in a natural sediment core from the Mount Elbert Stratigraphic Test Well. CT scanning was performed during hydrate formation and decomposition steps, and periodically while the hydrate samples remained under stable conditions for up to 60 days. The investigation revealed the impact of water saturation on location and morphology of hydrate in both laboratory and natural sediments during repeated hydrate formations. Significant redistribution of hydrate and water in the samples was observed over both the short and long term.

  3. LISA Pathfinder: First steps to observing gravitational waves from space

    Science.gov (United States)

    McNamara, Paul; LISA Pathfinder Collaboration

    2017-01-01

    With the first direct detection of gravitational waves a little over a year ago, the gravitational window to the Universe has been opened. The gravitational wave spectrum spans many orders of magnitude in frequency, with several of the most interesting astronomical sources emitting gravitational waves at frequencies only observable from space The European Space Agency (ESA) has been active in the field of space-borne gravitational wave detection for many years, and in 2013 selected the Gravitational Universe as the science theme for the third large class mission in the Cosmic Vision science programme. In addition, ESA took the step of developing the LISA Pathfinder mission to demonstrate the critical technologies required for a future mission. The goal of the LISA Pathfinder mission is to place a test body in free fall such that any external forces (acceleration) are reduced to levels lower than those expected from the passage of a gravitational wave LISA Pathfinder was launched on the 3rd December 2015 from the European Spaceport in Kourou, French Guiana. After a series of 6 apogee raising manoeuvres, the satellite left earth orbit, and travelled to its final science orbit around the first Sun-Earth Lagrange point (L1). Following a relatively short commissioning phase, science operations began on 1st March 2016. In the following 3 months over 100 experiments and over 1500hours of noise measurements have been performed, demonstrating that the observation of gravitational waves from space can be realised.

  4. SMM hard X-ray observations of the soft gamma-ray repeater 1806-20

    Science.gov (United States)

    Kouveliotou, C.; Norris, J. P.; Cline, T. L.; Dennis, B. R.; Desai, U. D.; Orwig, L. E.

    1987-01-01

    Six bursts from the soft gamma-ray repeater (SGR) 1806-20 have been recorded with the SMM Hard X-ray Burst Spectrometer during a highly active phase in 1983. Rise and decay times of less than 5 ns have been detected. Time profiles of these events indicate low-level emission prior to and after the main peaks. The results suggest that SGRs are distinguished from classical gamma-ray bursts by repetition, softer nonvarying spectra, short durations, simple temporal profiles, and a tendency for source locations to correlate with Population I objects. SGR characteristics differ from those of type I X-ray bursts, but they appear to have similarities with the type II bursts from the Rapid Burster.

  5. Clinical Observation on Chinese and Western Integrative Medicine in Treating Repeatedly Recurrent Chronic Pyelonephritis

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: To explore the clinical efficacy of Chinese and western integrative medicine (TCM-WM) in treating repeatedly recurrent chronic pyelonephritis (CPN) and its therapeutic mechanism. Methods: Ninety-one repeatedly recurrent CPN patients were randomly divided into 2 groups, the control group (45 cases) treated with sufficient amount of sensitive antibiotics and other WM, the treated group (46 cases) treated with above-mentioned WM complemented with TCM syndrome differentiation (SD). Results: In the treated group completely cured was 14 cases (30.4%), markedly effective 14 cases (30.4%), the total effective rate was 91.3%; while that of the control group was 4 (8.9%), 5 (11.1%), and 48.9% respectively, (P<0.05) and (P<0.01); the mean days of urinary bacteria and urinary routine negative conversion were in the treated group 19.6±12.6 days and 24.3±11.5 days, obviously shorter than those of the control group (35.6±14.6 days and 53.6±16.4 days), P<0.01; the various symptoms of the treated group improved or disappeared in a short time, while in the control group a few patients improved in a longer period (P<0.01); the various immune parameters improved in the treated group, while in the control group only IgA was elevated to some extent (P<0.05), in comparing these data, the difference was significant (P<0.01). Conclusion: The TCM-WM integrative treatment could obviously raise the clinical efficacy, accelerate the symptom improvement, and enhance the immune function.

  6. Meteorological radar methods for validating space observations of precipitation

    Science.gov (United States)

    Thiele, Otto W.

    1991-01-01

    Meteorological approaches to verification of space measurements of rainfall are examined; validation of Tropical Rainfall Measuring Mission (TRMM) observations is expected to depend significantly on ground-based radars. Two methods of comparison are initially contemplated. TRMM rainfall data over time periods of a month for large areas (500 x 500 km) are averaged and compared with similarly averaged ground truth measurements. Both the rainfall and height distribution data from TRMM are compared with the instantaneous values observed at one or more 'ground truth' stations and from airborne radar and radiometers as available.

  7. Space-based observation of the extensive airshowers

    Directory of Open Access Journals (Sweden)

    Ebisuzaki T.

    2013-06-01

    Full Text Available Space based observations of extensive air showers constitute the next experimental challenge for the study of the universe at extreme energy. Space observation will allow a “quantum jump” in the observational area available to detect the UV light tracks produced by particles with energies higher than 1020 eV. These are thought to reach the Earth almost undeflected by the cosmic magnetic field. This new technique will contribute to establish the new field of astronomy and astrophysics performed with charged particles and neutrinos at the highest energies. This idea was created by the incredible efforts of three outstanding comic ray physicists: John Linsley, Livio Scarsi, and Yoshiyuki Takahashi. This challenging technique has four significant merits in comparison with ground-based observations: 1 Very large observational area, 2 Well constrained distances of the showers, 3 Clear and stable atmospheric transmission in the above half troposphere, 4 Uniform Exposure across both the north and south skies. Four proposed and planned missions constitute the roadmap of the community: TUS, JEM-EUSO, KLPVE, and Super-EUSO will contribute step-by-step to establish this challenging field of research.

  8. Humanly space objects-Perception and connection with the observer

    Science.gov (United States)

    Balint, Tibor S.; Hall, Ashley

    2015-05-01

    Expanding humanity into space is an inevitable step in our quest to explore our world. Yet space exploration is costly, and the awaiting environment challenges us with extreme cold, heat, vacuum and radiation, unlike anything encountered on Earth. Thus, the few pioneers who experience it needed to be well protected throughout their spaceflight. The resulting isolation heightens the senses and increases the desire to make humanly connections with any other perceived manifestation of life. Such connections may occur via sensory inputs, namely vision, touch, sound, smell, and taste. This then follows the process of sensing, interpreting, and recognizing familiar patterns, or learning from new experiences. The desire to connect could even transfer to observed objects, if their movements and characteristics trigger the appropriate desires from the observer. When ordered in a familiar way, for example visual stimuli from lights and movements of an object, it may create a perceived real bond with an observer, and evoke the feeling of surprise when the expected behavior changes to something no longer predictable or recognizable. These behavior patterns can be designed into an object and performed autonomously in front of an observer, in our case an astronaut. The experience may introduce multiple responses, including communication, connection, empathy, order, and disorder. While emotions are clearly evoked in the observer and may seem one sided, in effect the object itself provides a decoupled bond, connectivity and communication between the observer and the artist-designer of the object. In this paper we will discuss examples from the field of arts and other domains, including robotics, where human perception through object interaction was explored, and investigate the starting point for new innovative design concepts and future prototype designs, that extend these experiences beyond the boundaries of Earth, while taking advantage of remoteness and the zero gravity

  9. Repeat Observations of New Impact Sites on Mars: Changes in Blast Zones

    Science.gov (United States)

    Daubar, I.; Geissler, P. E.; McEwen, A. S.; Dundas, C. M.; Byrne, S.

    2012-12-01

    New, dated craters on Mars (Malin et al. 2006, Daubar et al. 2012) are the freshest available examples of impact processes, and some of the only recently-modified surfaces with known ages for the initial surface disturbance. HiRISE has monitored many of these sites over three Mars years. The rates and characteristics of changes at these sites help us understand the initial impact processes and the modification processes that have occurred since. Future applications might include constraining ages of similar impacts that cannot be definitively dated by previous images and measuring variations in the rate of fading over time, perhaps even seasonal variations that would be important for dating dark marks that are only a few Mars years old. New impacts have an extended "blast zone" of (usually) lower albedo surrounding the craters. Blast zones are created by removal of high-albedo surface dust by various atmosphere/surface interactions of the shock waves associated with the descent and impact of the impactor and ejecta (Malin et al. 2006). Their creation could also (in addition?) be related to shock effects on small-scale surface texture. Features vary by site and include diffuse dark halos, dark arcuate or radial rays, light and dark-toned ejecta, slope streaks, and complex combinations thereof. Geissler et al. (2010a) reported that out of 14 sites with repeat imaging, only one site showed significant changes thus far. With 245 known impacts and many more repeat images, we can now extend this study to sites with different ages, target materials, and types of blast features. Surprisingly, some sites still show no detectable changes after three martian years, even after the 2007 global dust storm. In comparison, rover tracks fade on timescales of one martian year (Geissler et al. 2010b). Many other sites show changes, most commonly fading of the blast zone. Fading is most likely due to airfall of dust bringing the blast zones back to the ambient surrounding albedo. In

  10. BATMAN flies: a compact spectro-imager for space observation

    Science.gov (United States)

    Zamkotsian, Frederic; Ilbert, Olivier; Zoubian, Julien; Delsanti, Audrey; Boissier, Samuel; Lancon, Ariane

    2014-08-01

    BATMAN flies is a compact spectro-imager based on MOEMS for generating reconfigurable slit masks, and feeding two arms in parallel. The FOV is 25 x 12 arcmin2 for a 1m telescope, in infrared (0.85-1.7μm) and 500-1000 spectral resolution. Unique science cases for Space Observation are reachable with this deep spectroscopic multi-survey instrument: deep survey of high-z galaxies down to H=25 on 5 deg2 with continuum detection and all z>7 candidates at H=26.2 over 5 deg2; deep survey of young stellar clusters in nearby galaxies; deep survey of the Kuiper Belt of ALL known objects down to H=22. Pathfinder towards BATMAN in space is already running with ground-based demonstrators.

  11. Atmospheric Variability of CO2 impact on space observation Requirements

    Science.gov (United States)

    Swanson, A. L.; Sen, B.; Newhart, L.; Segal, G.

    2009-12-01

    If International governments are to reduce GHG levels by 80% by 2050, as recommended by most scientific bodies concerned with avoiding the most hazardous changes in climate, then massive investments in infrastructure and new technology will be required over the coming decades. Such an investment will be a huge commitment by governments and corporations, and while it will offer long-term dividends in lower energy costs, a healthier environment and averted additional global warming, the shear magnitude of upfront costs will drive a call for a monitoring and verification system. Such a system will be required to offer accountability to signatories of governing bodies, as well as, for the global public. Measuring the average global distribution of CO2 is straight forward, as exemplified by the long running station measurements managed by NOAA’s Global Monitoring Division that includes the longterm Keeling record. However, quantifying anthropogenic and natural source/sink distributions and atmospheric mixing have been much more difficult to constrain. And, yet, an accurate accounting of all anthropogenic source strengths is required for Global Treaty verification. The only way to accurately assess Global GHG emissions is to construct an integrated system of ground, air and space based observations with extensive chemical modeling capabilities. We look at the measurement requirements for the space based component of the solutions. To determine what space sensor performance requirements for ground resolution, coverage, and revisit, we have analyzed regional CO2 distributions and variability using NASA and NOAA aircraft flight campaigns. The results of our analysis are presented as variograms showing average spatial variability over several Northern Hemispheric regions. There are distinct regional differences with the starkest contrast between urban versus rural and Coastal Asia versus Coastal US. The results suggest specific consequences on what spatial and temporal

  12. Observing power blackouts from space - A disaster related study

    Science.gov (United States)

    Aubrecht, C.; Elvidge, C. D.; Ziskin, D.; Baugh, K. E.; Tuttle, B.; Erwin, E.; Kerle, N.

    2009-04-01

    capability of detecting power blackouts in OLS data have been identified (e.g. sunlight, heavy cloud cover and bright moonlight). Furthermore, the change detection procedure only works when power blackouts happen or still persist at night at the time of an OLS overpass. In some cases (e.g. Hurricane Katrina) it has been possible to track the gradual recovery of power by repeating the procedure on nights following a disaster event. In this paper several examples of successful power blackout detection following natural disasters including hurricanes (e.g. Isabel 2003 and Wilma 2005 in the USA) and earthquakes (e.g. Gujarat Earthquake 2001 in India) will be presented, whereas overlaid hurricane paths and earthquake epicenters serve as landmarks and indicate locations around the potential highest impact. Disaster impact assessment and post-disaster research is strongly related to impacts on population, related infrastructure and activities (Kerle et al. 2005, Zhang and Kerle 2008). In particular in the case of emergency management and response humans are the main actors and first-pass assessment of affected population and locations of affected areas are essential. Space-based power blackout detection, as described above, has the potential to delineate the spatial extent of the disaster impact. Overlaying the respective OLS data with regional population data such as LandScan (Dobson et al. 2000) or Gridded Population of the World (CIESIN and CIAT 2005) allows estimating a potential number of affected people. Without a doubt such estimates comprise a considerable number of uncertainties. However, the capability of providing the information in near-real time as offered by using DMSP-OLS makes the presented approach very valuable for emergency and disaster managers worldwide. REFERENCES Center for International Earth Science Information Network CIESIN at Columbia University, and Centro Internacional de Agricultura Tropical CIAT (2005). Gridded Population of the World Version 3 (GPWv

  13. Giant Planet Observations with the James Webb Space Telescope

    CERN Document Server

    Norwood, James; Fletcher, Leigh N; Orton, Glenn; Irwin, Patrick G J; Atreya, Sushil; Rages, Kathy; Cavalié, Thibault; Sánchez-Lavega, Agustin; Hueso, Ricardo; Chanover, Nancy

    2015-01-01

    This white paper examines the benefit of the upcoming James Webb Space Telescope for studies of the Solar System's four giant planets: Jupiter, Saturn, Uranus, and Neptune. JWST's superior sensitivity, combined with high spatial and spectral resolution, will enable near- and mid-infrared imaging and spectroscopy of these objects with unprecedented quality. In this paper we discuss some of the myriad scientific investigations possible with JWST regarding the giant planets. This discussion is preceded by the specifics of JWST instrumentation most relevant to giant planet observations. We conclude with identification of desired pre-launch testing and operational aspects of JWST that would greatly benefit future studies of the giant planets.

  14. Space-Based Observations of Satellites From the MOST Microsatellite

    Science.gov (United States)

    2006-11-01

    observations spatiales canadiennes d’un objet en orbite terrestre . Deux satellites de géolocalisation GPS ont été suivis à l’aide du télescope optique monté...the derived orbital metric data with high precision ephemerides yielded root mean square errors of 13 arcseconds. The errors are shown to result...space surveillance from an orbiting platform. Résumé Le 12 octobre 2005, le microsatellite MOST du Canada a acquis les premières images

  15. Do monkey F5 mirror neurons show changes in firing rate during repeated observation of natural actions?

    Science.gov (United States)

    Kilner, J M; Kraskov, A; Lemon, R N

    2014-03-01

    Mirror neurons were first discovered in area F5 of macaque monkeys. In humans, noninvasive studies have demonstrated an increased blood oxygen level-dependent (BOLD) signal in homologous motor areas during action observation. One approach to demonstrating that this indicates the existence of mirror neurons in humans has been to employ functional (f)MRI adaptation to test whether the same population of neurons is active during both observation and execution conditions. Although a number of human studies have reported fMRI adaptation in these areas, a recent study has shown that macaque mirror neurons do not attenuate their firing rate with two repetitions. Here we investigated whether mirror neurons modulate their firing rate when monkeys observed the same repeated natural action multiple times. We recorded from 67 mirror neurons in area F5 of two macaque monkeys while they observed an experimenter perform a reach-to-grasp action on a small food reward using a precision grip. Although no changes were detectable for the first two repetitions, we show that both the firing rate and the latency at which mirror neurons discharged during observation were subtly modulated by the repetition of the observed action over 7-10 trials. Significant adaption was mostly found in the period immediately before the grasp was performed. We also found that the local field potential activity in F5 (beta-frequency range, 16-23 Hz), which is attenuated during action observation, also showed systematic changes with repeated observation. These LFP changes occurred well in advance of the mirror neuron adaptation. We conclude that macaque mirror neurons can show intra-modal adaptation, but whether this is related to fMRI adaptation of the BOLD signal requires further investigation.

  16. Physical features observation: is it repeatable in zygosity determination of Chinese adult twins?

    Science.gov (United States)

    Gao, Wenjing; Li, Liming; Cao, Weihua; Zhan, Siyan; Zhao, Yunlong; Wang, Hui; Hu, Yonghua

    2010-02-01

    This study reports on the inter- and intrarater reliability of physical features observation. Study subjects were 176 Chinese adult persons, consisting of 89 males and 87 females. Three trained research assistants responded simultaneously and respectively to 12 items regarding the subject's physical features including 'hair', 'Mongoloid folds', left and right 'ear lobes', 'earwax', 'nostril shape', 'tongue rolling', left and right 'hitchhiker's thumb', 'mid-digital hair' and left and right 'simian crease' at the moment of interview. And 14 days later, these subjects received the same observation once again. The results showed that the inter- and intra-observer agreements of 'hair', 'earwax', 'tongue rolling', 'mid-digital hair' and 'simian crease' were almost perfect with most kappa (kappa) coefficients >or= .80, while 'Mongoloid fold' and 'nostril shape' showed poor inter-observer agreement and 'nostril shape' showed poor intra-observer agreement (kappa digital hair' and 'simian crease' could be considered in zygosity determination of Chinese adult twins, while the two features, 'Mongoloid fold' and 'nostril shape', should be abandoned.

  17. Inter- and Intra-Observer Repeatability of Quantitative Whole-Body, Diffusion-Weighted Imaging (WBDWI in Metastatic Bone Disease.

    Directory of Open Access Journals (Sweden)

    Matthew D Blackledge

    Full Text Available Quantitative whole-body diffusion-weighted MRI (WB-DWI is now possible using semi-automatic segmentation techniques. The method enables whole-body estimates of global Apparent Diffusion Coefficient (gADC and total Diffusion Volume (tDV, both of which have demonstrated considerable utility for assessing treatment response in patients with bone metastases from primary prostate and breast cancers. Here we investigate the agreement (inter-observer repeatability between two radiologists in their definition of Volumes Of Interest (VOIs and subsequent assessment of tDV and gADC on an exploratory patient cohort of nine. Furthermore, each radiologist was asked to repeat his or her measurements on the same patient data sets one month later to identify the intra-observer repeatability of the technique. Using a Markov Chain Monte Carlo (MCMC estimation method provided full posterior probabilities of repeatability measures along with maximum a-posteriori values and 95% confidence intervals. Our estimates of the inter-observer Intraclass Correlation Coefficient (ICCinter for log-tDV and median gADC were 1.00 (0.97-1.00 and 0.99 (0.89-0.99 respectively, indicating excellent observer agreement for these metrics. Mean gADC values were found to have ICCinter = 0.97 (0.81-0.99 indicating a slight sensitivity to outliers in the derived distributions of gADC. Of the higher order gADC statistics, skewness was demonstrated to have good inter-user agreement with ICCinter = 0.99 (0.86-1.00, whereas gADC variance and kurtosis performed relatively poorly: 0.89 (0.39-0.97 and 0.96 (0.69-0.99 respectively. Estimates of intra-observer repeatability (ICCintra demonstrated similar results: 0.99 (0.95-1.00 for log-tDV, 0.98 (0.89-0.99 and 0.97 (0.83-0.99 for median and mean gADC respectively, 0.64 (0.25-0.88 for gADC variance, 0.85 (0.57-0.95 for gADC skewness and 0.85 (0.57-0.95 for gADC kurtosis. Further investigation of two anomalous patient cases revealed that a very small

  18. Hubble Space Telescope: The Telescope, the Observations & the Servicing Mission

    Science.gov (United States)

    1999-11-01

    Today the HST Archives contain more than 260 000 astronomical observations. More than 13 000 astronomical objects have been observed by hundreds of different groups of scientists. Direct proof of the scientific significance of this project is the record-breaking number of papers published : over 2400 to date. Some of HST's most memorable achievements are: * the discovery of myriads of very faint galaxies in the early Universe, * unprecedented, accurate measurements of distances to the farthest galaxies, * significant improvement in the determination of the Hubble constant and thus the age of the Universe, * confirmation of the existence of blacks holes, * a far better understanding of the birth, life and death of stars, * a very detailed look at the secrets of the process by which planets are created. Europe and HST ESA's contribution to HST represents a nominal investment of 15%. ESA provided one of the two imaging instruments - the Faint Object Camera (FOC) - and the solar panels. It also has 15 scientists and computer staff working at the Space Telescope Science Institute in Baltimore (Maryland). In Europe the astronomical community receives observational assistance from the Space Telescope European Coordinating Facility (ST-ECF) located in Garching, Munich. In return for ESA's investment, European astronomers have access to approximately 15% of the observing time. In reality the actual observing time competitively allocated to European astronomers is closer to 20%. Looking back at almost ten years of operation, the head of ST-ECF, European HST Project Scientist Piero Benvenuti states: "Hubble has been of paramount importance to European astronomy, much more than the mere 20% of observing time. It has given the opportunity for European scientists to use a top class instrument that Europe alone would not be able to build and operate. In specific areas of research they have now, mainly due to HST, achieved international leadership." One of the major reasons for

  19. Solar System Observations with the James Webb Space Telescope

    Science.gov (United States)

    Norwood, James; Hammel, Heidi; Milam, Stefanie; Stansberry, John; Lunine, Jonathan; Chanover, Nancy; Hines, Dean; Sonneborn, George; Tiscareno, Matthew; Brown, Michael; hide

    2016-01-01

    The James Webb Space Telescope (JWST) will enable a wealth of new scientific investigations in the near- and mid-infrared, with sensitivity and spatial/spectral resolution greatly surpassing its predecessors. In this paper, we focus upon Solar System science facilitated by JWST, discussing the most current information available concerning JWST instrument properties and observing techniques relevant to planetary science. We also present numerous example observing scenarios for a wide variety of Solar System targets to illustrate the potential of JWST science to the Solar System community. This paper updates and supersedes the Solar System white paper published by the JWST Project in 2010. It is based both on that paper and on a workshop held at the annual meeting of the Division for Planetary Sciences in Reno, NV, in 2012.

  20. The Potential of Small Space Telescopes for Exoplanet Observations

    Science.gov (United States)

    Serabyn, E.

    2010-01-01

    The imaging of faint exoplanets near bright stars requires the development of very high contrast detection techniques, including both precise wavefront control and deep starlight rejection. A system-level proof-of-principle experiment carried out at at the Palomar Observatory has recently demonstrated that exoplanets can be detected very near stars even with a fairly small (1.5 m diameter) telescope aperture, such as someday might be used by a first space-based exoplanet imaging mission. Using fine-scale wavefront correction across this small aperture, together with fine pointing and focus control, pre- and post-detection speckle reduction, and a vector vortex coronagraph, it has been possible to achieve extremely good starlight rejection within a small number of diffractions beams of the stellar position. This performance has recently allowed the imaging of the three HR8799 planets and the HD32297 disk, thus providing a first system-level validation of the steps needed to achieve high-contrast observations at very small angles. These results thus serve to highlight the potential of small space telescopes aiming at high-contrast exoplanet observations. Specifically, a small-angle coronagraph enables the use of smaller telescopes, thus potentially reducing mission cost significantly.

  1. A new space technology for ocean observation: the SMOS mission

    Directory of Open Access Journals (Sweden)

    Jordi Font

    2012-09-01

    Full Text Available Capability for sea surface salinity observation was an important gap in ocean remote sensing in the last few decades of the 20th century. New technological developments during the 1990s at the European Space Agency led to the proposal of SMOS (Soil Moisture and Ocean Salinity, an Earth explorer opportunity mission based on the use of a microwave interferometric radiometer, MIRAS (Microwave Imaging Radiometer with Aperture Synthesis. SMOS, the first satellite ever addressing the observation of ocean salinity from space, was successfully launched in November 2009. The determination of salinity from the MIRAS radiometric measurements at 1.4 GHz is a complex procedure that requires high performance from the instrument and accurate modelling of several physical processes that impact on the microwave emission of the ocean’s surface. This paper introduces SMOS in the ocean remote sensing context, and summarizes the MIRAS principles of operation and the SMOS salinity retrieval approach. It describes the Spanish SMOS high-level data processing centre (CP34 and the SMOS Barcelona Expert Centre on Radiometric Calibration and Ocean Salinity (SMOS-BEC, and presents a preliminary validation of global sea surface salinity maps operationally produced by CP34.

  2. Steady subsidence of a repeatedly erupting caldera through InSAR observations: Aso, Japan

    KAUST Repository

    Nobile, Adriano

    2017-04-05

    The relation between unrest and eruption at calderas is still poorly understood. Aso caldera, Japan, shows minor episodic phreatomagmatic eruptions associated with steady subsidence. We analyse the deformation of Aso using SAR images from 1993 to 2011 and compare it with the eruptive activity. Although the dataset suffers from limitations (e.g. atmospheric effects, coherence loss, low signal-to-noise ratio), we observe a steady subsidence signal from 1996 to 1998, which suggests an overall contraction of a magmatic source below the caldera centre, from 4 to 5 km depth. We propose that the observed contraction may have been induced by the release of the magmatic fluids feeding the eruptions. If confirmed by further data, this hypothesis suggests that degassing processes play a crucial role in triggering minor eruptions within open conduit calderas, such as at Aso. Our study underlines the importance of defining any eruptive potential also from deflating magmatic systems with open conduit.

  3. Observing Supernova 1987A with the Refurbished Hubble Space Telescope

    Science.gov (United States)

    France, Kevin; McCray, Richard; Heng, Kevin; Kirshner, Robert P.; Challis, Peter; Bouchet, Patrice; Crotts, Arlin; Dwek, Eli; Fransson, Claes; Garnavich, Peter M.; hide

    2010-01-01

    The young remnant of supernova 1987A (SN 1987A) offers an unprecedented glimpse into the hydrodynamics and kinetics of fast astrophysical shocks. We have been monitoring SN 1987A with the Hubble Space Telescope (HST) since it was launched. The recent repair of the Space Telescope Imaging Spectrograph (STIS) allows us to compare observations in 2004, just before its demise, with those in 2010, shortly after its resuscitation by NASA astronauts. We find that the Ly-alpha and H-alpha lines from shock emission continue to brighten, while their maximum velocities continue to decrease. We report evidence for nearly coherent, resonant scattering of Lya photons (to blueshifts approximately -12,000 km /s) from hotspots on the equatorial ring. We also report emission to the red of Ly-alpha that we attribute to N v lambda lambda 1239,1243 Angstrom line emission. These lines are detectable because, unlike hydrogen atoms, N4+ ions emit hundreds of photons before they are ionized. The profiles of the N v lines differ markedly from that of H-alpha. We attribute this to scattering of N4+ ions by magnetic fields in the ionized plasma. Thus, N v emission provides a unique probe of the isotropization zone of the collisionless shock. Observations with the recently installed Cosmic Origins Spectrograph (COS) will enable us to observe the N v lambda lambda 1239,1243 Angstrom line profiles with much higher signal-to-noise ratios than possible with STIS and may reveal lines of other highly ionized species (such as C IVlambda lambda 1548,1551 Angstrom) that will test our explanation for the N v emission

  4. Space perception of strabismic observers in the real world environment.

    Science.gov (United States)

    Ooi, Teng Leng; He, Zijiang J

    2015-02-19

    Space perception beyond the near distance range (>2 m) is important for target localization, and for directing and guiding a variety of daily activities, including driving and walking. However, it is unclear whether the absolute (egocentric) localization of a single target in the intermediate distance range requires binocular vision, and if so, whether having subnormal stereopsis in strabismus impairs one's ability to localize the target. We investigated this by measuring the perceived absolute location of a target by observers with normal binocular vision (n = 8; mean age, 24.5 years) and observers with strabismus (n = 8; mean age, 24.9 years) under monocular and binocular conditions. The observers used the blind walking-gesturing task to indicate the judged location of a target located at various viewing distances (2.73-6.93 m) and heights (0, 30, and 90 cm) above the floor. Near stereopsis was assessed with the Randot Stereotest. Both groups of observers accurately judged the absolute distance of the target on the ground (height = 0 cm) either with monocular or binocular viewing. However, when the target was suspended in midair, the normal observers accurately judged target location with binocular viewing, but not with monocular viewing (mean slant angle, 0.8° ± 0.5° vs. 7.4° ± 1.4°; P monocular viewing (r(2) = 0.0002, P = 0.963). Locating a single target on the ground is sufficient with monocular depth information, but binocular depth information is required when the target is suspended in midair. Since the absolute binocular disparity information of the single target is weak beyond 2 m, we suggest the visual system localizes the single target using the relative binocular disparity information between the midair target and the visible ground surface. Consequently, strabismic observers with residual stereopsis localize a target more accurately than their counterparts without stereo ability. Copyright 2015 The Association for Research in Vision and

  5. Space weathering of asteroids: Lessons from Itokawa for future observations

    Science.gov (United States)

    Sasaki, Sho; HIroi, Takahiro

    2016-07-01

    Introduction Space weathering of surface silicate minerals is the main process that should control the change of brightness and color of airless silicate bodies such and the Moon, Mercury and asteroids. Spectra of S-type asteroids exhibit more overall depletion and reddening, and more weakening of absorption bands than spectra of ordinary chondrites. These spectral mismatches are explained by the space weathering, where the primary proven mechanism of such spectral change is production of nanophase metallic iron particles (npFe0) 1), which were confirmed in the amorphous rim of lunar soil grains 2,3). Vapor-deposition through at high-velocity dust particle impacts as well as implantation of intensive solar wind ions would be responsible for producing the space weathering rims bearing nano-iron particles (npFe0). Simulation experiments using nanosecond pulse laser successfully produced vapor-deposition type npFe0 to change optical properties 4,5,6). Laser experiments showed that pyroxene would be weathered less than olivine, for pyroxene, pulse laser irradiation produced melt (amorphous) droplets containing npFe0, rather than vapour deposited rim that should provide stronger optical effect trough multiple scattering of incidental light. Itokawa Observed by Remote Sensing In November 2005, Japanese Asteroid Sample Return Mission HAYABUSA spacecraft rendezvoused S-type asteroid (25143) Itokawa. Optically, the surface of Itokawa is divided into brighter (and bluer) areas and darker (and redder) areas 7,8). In rough zones, dark boulder-rich surfaces usually superpose on bright materials. The near-infrared spectrometer (NIRS) confirmed previous disk-integrated results that suggested Itokawa's spectrum closely matched a weakly weathered LL5/6 chondrite 9). Although the surface is covered with rocks and is apparently lack of fine regolith, Itokawa's surface show darkening and reddening by space weathering. Experimental results suggest rocky meteorite fragments can be

  6. Repeatability of measurements: Non-Hermitian observables and quantum Coriolis force

    Science.gov (United States)

    Gardas, Bartłomiej; Deffner, Sebastian; Saxena, Avadh

    2016-08-01

    A noncommuting measurement transfers, via the apparatus, information encoded in a system's state to the external "observer." Classical measurements determine properties of physical objects. In the quantum realm, the very same notion restricts the recording process to orthogonal states as only those are distinguishable by measurements. Therefore, even a possibility to describe physical reality by means of non-Hermitian operators should volens nolens be excluded as their eigenstates are not orthogonal. Here, we show that non-Hermitian operators with real spectra can be treated within the standard framework of quantum mechanics. Furthermore, we propose a quantum canonical transformation that maps Hermitian systems onto non-Hermitian ones. Similar to classical inertial forces this map is accompanied by an energetic cost, pinning the system on the unitary path.

  7. Breath acidification in adolescent runners exposed to atmospheric pollution: A prospective, repeated measures observational study

    Directory of Open Access Journals (Sweden)

    Van Sickle David

    2008-03-01

    Full Text Available Abstract Background Vigorous outdoors exercise during an episode of air pollution might cause airway inflammation. The purpose of this study was to examine the effects of vigorous outdoor exercise during peak smog season on breath pH, a biomarker of airway inflammation, in adolescent athletes. Methods We measured breath pH both pre- and post-exercise on ten days during peak smog season in 16 high school athletes engaged in daily long-distance running in a downwind suburb of Atlanta. The association of post-exercise breath pH with ambient ozone and particulate matter concentrations was tested with linear regression. Results We collected 144 pre-exercise and 146 post-exercise breath samples from 16 runners (mean age 14.9 years, 56% male. Median pre-exercise breath pH was 7.58 (interquartile range: 6.90 to 7.86 and did not change significantly after exercise. We observed no significant association between ambient ozone or particulate matter and post-exercise breath pH. However both pre- and post-exercise breath pH were strikingly low in these athletes when compared to a control sample of 14 relatively sedentary healthy adults and to published values of breath pH in healthy subjects. Conclusion Although we did not observe an acute effect of air pollution exposure during exercise on breath pH, breath pH was surprisingly low in this sample of otherwise healthy long-distance runners. We speculate that repetitive vigorous exercise may induce airway acidification.

  8. Steady subsidence of a repeatedly erupting caldera through InSAR observations: Aso, Japan

    Science.gov (United States)

    Nobile, Adriano; Acocella, Valerio; Ruch, Joel; Aoki, Yosuke; Borgstrom, Sven; Siniscalchi, Valeria; Geshi, Nobuo

    2016-04-01

    The relation between unrest and eruption at calderas is still poorly understood. Aso caldera, Japan, shows minor episodic eruptions, mainly phreatic, associated with steady subsidence. We analyse the recent deformation of Aso using SAR images from 1993 to 2011 and compare this with the eruptive activity. Although the dataset suffers from limitations (e.g., atmospheric effects, coherence loss, low signal to noise ratio), we observe a steady subsidence signal from 1996 to 1998, that suggests an overall contraction of a magmatic source below the caldera centre, from 4.5 to 7 km depth. Because of the similar volumes of the contracting source and erupted material, we propose that the contraction may have been induced by the release of the magmatic fluids feeding the eruptions. If confirmed by further data, this hypothesis suggests that degassing processes play a crucial role in triggering minor eruptions within open conduit calderas, as at Aso. These features underline the importance of defining any eruptive potential also from deflating magmatic systems with open conduit.

  9. Simultaneous X-Ray, Gamma-Ray, and Radio Observations of the Repeating Fast Radio Burst FRB 121102

    Science.gov (United States)

    Scholz, P.; Bogdanov, S.; Hessels, J. W. T.; Lynch, R. S.; Spitler, L. G.; Bassa, C. G.; Bower, G. C.; Burke-Spolaor, S.; Butler, B. J.; Chatterjee, S.; Cordes, J. M.; Gourdji, K.; Kaspi, V. M.; Law, C. J.; Marcote, B.; McLaughlin, M. A.; Michilli, D.; Paragi, Z.; Ransom, S. M.; Seymour, A.; Tendulkar, S. P.; Wharton, R. S.

    2017-09-01

    We undertook coordinated campaigns with the Green Bank, Effelsberg, and Arecibo radio telescopes during Chandra X-ray Observatory and XMM-Newton observations of the repeating fast radio burst FRB 121102 to search for simultaneous radio and X-ray bursts. We find 12 radio bursts from FRB 121102 during 70 ks total of X-ray observations. We detect no X-ray photons at the times of radio bursts from FRB 121102 and further detect no X-ray bursts above the measured background at any time. We place a 5σ upper limit of 3 × 10‑11 erg cm‑2 on the 0.5–10 keV fluence for X-ray bursts at the time of radio bursts for durations fast radio bursts in general.

  10. Remote observations of reentering spacecraft including the space shuttle orbiter

    Science.gov (United States)

    Horvath, Thomas J.; Cagle, Melinda F.; Grinstead, Jay H.; Gibson, David M.

    Flight measurement is a critical phase in development, validation and certification processes of technologies destined for future civilian and military operational capabilities. This paper focuses on several recent NASA-sponsored remote observations that have provided unique engineering and scientific insights of reentry vehicle flight phenomenology and performance that could not necessarily be obtained with more traditional instrumentation methods such as onboard discrete surface sensors. The missions highlighted include multiple spatially-resolved infrared observations of the NASA Space Shuttle Orbiter during hypersonic reentry from 2009 to 2011, and emission spectroscopy of comparatively small-sized sample return capsules returning from exploration missions. Emphasis has been placed upon identifying the challenges associated with these remote sensing missions with focus on end-to-end aspects that include the initial science objective, selection of the appropriate imaging platform and instrumentation suite, target flight path analysis and acquisition strategy, pre-mission simulations to optimize sensor configuration, logistics and communications during the actual observation. Explored are collaborative opportunities and technology investments required to develop a next-generation quantitative imaging system (i.e., an intelligent sensor and platform) with greater capability, which could more affordably support cross cutting civilian and military flight test needs.

  11. A Tropical "NAT-like" belt observed from space

    CERN Document Server

    Chepfer, Hélène; 10.1029/2008GL036289

    2009-01-01

    The optical properties of cold tropical tropopause clouds are examined on a global scale, using two years of space-borne lidar observations from CALIPSO (June 2006 ? May 2008). The linear depolarization ratio, color ratio and backscatter signal are analyzed in tropical clouds colder than 200 K in a way similar to recent studies of Polar Stratospheric Clouds (PSCs). It is found that the three categories of particles encountered in PSC (Ice, Sulfate Ternary Solutions or STS, and Nitric Acid Trihydrate or NAT) do also occur in tropical cold cloud layers. Particles with optical properties similar to NAT are few, but they cover the tropical belt and represent about 20% of cold cloud tropical particles. The optical behavior of these particles requires them to be small, non-spherical, optically thin, and persistent in the TTL at temperatures colder than 200 K; NAT particles and very small ice crystals meet these criteria.

  12. Plant development in space: Observations on root formation and growth

    Science.gov (United States)

    Levine, H. G.; Kann, R. P.; Krikorian, Abraham D.

    1990-01-01

    Root growth in space is discussed and observations on root production from plants flown as part of the Chromex project that were defined as to their origin, stage of development and physiological status, are presented. Roots were generated from fully differentiated, aseptically maintained individuals of Haplopappus gracilis (Compositae) under spaceflight conditions. Results are compared for tissue culture generated plantlets and comparably sized seedling clone individuals, both of which had their roots trimmed on Earth before they were loaded into NASA's plant growth unit and subjected to a 5 day shuttle flight (STS-29). Asepsis was maintained throughout the experiment. Overall root production was 40 to 50 percent greater under spaceflight conditions than during ground control tests. However, root formation slowed down towards the end of the flight. This decrease in new roots did not occur in the ground controls that sought to simulate flight except for microgravity.

  13. Space shuttle observation of an unusual transient atmospheric emission

    Science.gov (United States)

    Yair, Yoav; Price, Colin; Ziv, Baruch; Israelevich, Peter L.; Sentman, Davis D.; São-Sabbas, Fernanda T.; Devir, Adam D.; Sato, Mitsuteru; Rodger, Craig J.; Moalem, Meir; Greenberg, Eran; Yaron, Ofer

    2005-01-01

    We report an observation of an unusual transient luminous event (TLE) detected in the near IR, south of Madagascar above the Indian Ocean. The event was imaged from the space shuttle Columbia during the MEIDEX sprite campaign [Yair et al., 2004]. It was delayed 0.23 seconds from a preceding visual lightning flash which was horizontally displaced >1000 km from the event. The calculated brightness in the 860 (+/-50) nm filter was ~310 +/- 30 kR, and the morphology of the emitting volume did not resemble any known class of TLE (i.e., sprites, ELVES or halos). This TIGER event (Transient Ionospheric Glow Emission in Red) may constitute a new class of TLE, not necessarily induced by a near-by thunderstorm. We discuss possible generation mechanisms, including the conjugate sprite hypothesis caused by lightning at the magnetic mirror point, lightning-induced electron precipitation and an extraterrestrial source, meteoric or cometary.

  14. Ocean Surface Carbon Dioxide Fugacity Observed from Space

    Science.gov (United States)

    Liu, W. Timothy; Xie, Xiaosu

    2014-01-01

    We have developed and validated a statistical model to estimate the fugacity (or partial pressure) of carbon dioxide (CO2) at sea surface (pCO2sea) from space-based observations of sea surface temperature (SST), chlorophyll, and salinity. More than a quarter million in situ measurements coincident with satellite data were compiled to train and validate the model. We have produced and made accessible 9 years (2002-2010) of the pCO2sea at 0.5 degree resolutions daily over the global ocean. The results help to identify uncertainties in current JPL Carbon Monitoring System (CMS) model-based and bottom-up estimates over the ocean. The utility of the data to reveal multi-year and regional variability of the fugacity in relation to prevalent oceanic parameters is demonstrated.

  15. HXMT satellite for space hard X-ray observation

    Science.gov (United States)

    Wu, Y.; Ren, D.; You, Z.

    Space hard X-ray in the energy band from 10Kev to 250KeV is very important to the research of high energy astrophysical processes, especially some of the fundamental problems in astrophysics. Due to imaging difficulty in the hard X-ray band, Observations made over this band is comparatively less than other bands such as soft X-ray and gamma -ray. Up to now, there has been no hard X ray all sky- survey of high sensitivity. Based on the Direct Demodulation imaging method recently developed, the Hard X- ray Modulation Telescope(HXMT) mission is proposed under the Major State Basic Research Development Program of China. The scientific objective of HXMT mission is to realize the first hard X-ray all sky survey of high sensitivy and angular resolution in the world, and to present the first detailed sky map of hard X r a y - distribution. In this article, the physical basis, the imaging principle and the basic structure of HXMT are briefly introduced. The expected angular resolution of observation and position accuracy of radiant source are 2' and 0.2' respectively. Based on the analysis of the mission requirement of HXMT, the mission design of HXMT satellite is presented in which the concept of integrative design approach is presented and implemented. The design of spacecraft subsystems such as strcuture,C&DH and energy are also introduced. To meet the high precision demand of the attitude determination of HXMT, a new Attitude Determination &Control Subsystem(ADCS) scheme is presented in which the Microminiature Inertial Measurement Unit(MIMU) is employed as one of the key attitude sensors. Combined with star tracker, the expected attitude measurement accuracy is 0.01° in the normal mission mode. Based on all these thoughts, the ADCS is analyzed and its general design is presented in the paper. As the first chinese space hard X-ray observatory, the design approach of HXMT satellite is also helpful for other space exploration missions such as solar activity inspection

  16. Usefulness of multichannel Holter ECG recording in the third intercostal space for detecting type 1 Brugada ECG: comparison with repeated 12-lead ECGs.

    Science.gov (United States)

    Shimeno, Kenji; Takagi, Masahiko; Maeda, Keiko; Tatsumi, Hiroaki; Doi, Atsushi; Yoshiyama, Minoru

    2009-09-01

    Type 1 Brugada ECG is essential for the diagnosis of Brugada syndrome. We aimed to evaluate the usefulness of multichannel Holter ECG recording in the third intercostal space for detecting type 1 Brugada ECG. We enrolled 60 consecutive individuals with type 1 Brugada ECG and 31 individuals with type 2 or 3 Brugada ECG, in the presence or absence of Na+ channel blockers. All individuals underwent 12-lead ECGs recorded in the standard position and the third intercostal space at least 5 times every 3 months (4L-ECGs, 3L-ECGs, respectively) and multichannel Holter ECG. On multichannel Holter ECG, the precordial electrodes were attached at standard positions (4L-Holter) and the third intercostal space (3L-Holter) for leads V1 and V2. Among the 60 individuals, type 1 Brugada ECG in 4L-ECGs, 3L-ECGs, 4L-Holter, and 3L-Holter was detected in 15 (25%), 26 (43.3%), 23 (38.3%), and 33 individuals (55%), respectively, whereas detected in none of the 31 individuals. The documented duration of type 1 Brugada ECG on 3L-Holter was significantly longer than that on 4L-Holter (700 +/- 467 vs 372 +/- 422 min; P = 0.01, 3L-Holter vs 4L-Holter, respectively), and type 1 Brugada ECG was most frequently observed between 6 pm and 12 pm. Neither the presence nor the duration of the appearance of type 1 Brugada ECG differed significantly between symptomatic and asymptomatic individuals. Multichannel Holter ECG recording in the third intercostal space is more sensitive and useful for the diagnosis of type 1 Brugada ECG than repeated 12-lead ECGs or multichannel Holter ECG in the standard position.

  17. Tectonomagnetic study in the seismoactive area of Narmada–Son lineament, central India: Preliminary results on repeat field observations

    Indian Academy of Sciences (India)

    S Y Waghmare; S D Pimprikar; P B Gawali; L Carlo; A G Patil

    2009-06-01

    Repeated measurements of the total geomagnetic field on the five profiles have revealed a picture of stress-induced tectonomagnetic effect in the form of secular variation of the total geomagnetic field in the tectonically and seismically active area of Jabalpur and adjoining areas of the Narmada-Son lineament (NSL),central India.For this experiment,a reference base station was established within the study area at Jabalpur.Using proton precession magnetometers with a sensitivity of 0.1 nT, simultaneous measurements of total geomagnetic field were made annually at the base and all field stations.Five cycles of repeated observations have been performed between 2003 and 2007.For data analysis,a difference method has been applied and the residuals have been calculated as secular variations of the total geomagnetic field with values ranging from ± 0.1nT to about > ± 14.6nT/yr over the different stations.The anomalies in secular variation of the total geomagnetic field may be related to anomalous accumulation of tectonic stresses and tensions on the deep fault zones and crustal blocks due to recent geodynamic processes and active geological inhomogeneities in the NSL.

  18. Characterization of informational completeness for covariant phase space observables

    Science.gov (United States)

    Kiukas, J.; Lahti, P.; Schultz, J.; Werner, R. F.

    2012-10-01

    In the nonrelativistic setting with finitely many canonical degrees of freedom, a shift-covariant phase space observable is uniquely characterized by a positive operator of trace one and, in turn, by the Fourier-Weyl transform of this operator. We study three properties of such observables, and characterize them in terms of the zero set of this transform. The first is informational completeness, for which it is necessary and sufficient that the zero set has dense complement. The second is a version of informational completeness for the Hilbert-Schmidt class, equivalent to the zero set being of measure zero, and the third, known as regularity, is equivalent to the zero set being empty. We give examples demonstrating that all three conditions are distinct. The three conditions are the special cases for p = 1, 2, ∞ of a more general notion of p-regularity defined as the norm density of the span of translates of the operator in the Schatten-p class. We show that the relation between zero sets and p-regularity can be mapped completely to the corresponding relation for functions in classical harmonic analysis.

  19. Observations on Irreducible Sets and Sob er Spaces

    Institute of Scientific and Technical Information of China (English)

    CHEN Dong-li; ZHANG Yan

    2014-01-01

    This paper, using the monads theory in the topological space, gives a new charac-terization of irreducible sets in the nonstandard enlarged models. Further, the discretization expression of Sober topological spaces is presented.

  20. Earth observations from space: History, promise, and reality. Executive summary

    Science.gov (United States)

    1995-01-01

    In this report the Committee on Earth Studies (CES), a standing committee of the Space Studies Board (SSB) within the National Research Council (NRC), reviews the recent history (nominally from 1981 to 1995) of the U.S. earth observations programs that serve civilian needs. The principal observations programs examined are those of NASA and the National Oceanic and Atmospheric Administration (NOAA). The Air Force' s Defense Meteorological Satellite Program (DMSP) is discussed, but only from the perspective of its relationship to civil needs and the planned merger with the NOAA polar-orbiting system. The report also reviews the interfaces between the earth observations satellite programs and the major national and international environmental monitoring and research programs. The monitoring and research programs discussed are the U.S. Global Change Research Program (USGCRP), the International Geosphere-Biosphere Program (IGBP), the World Climate Research Program (WCRP), related international scientific campaigns, and operational programs for the sharing and application of environmental data. The purpose of this report is to provide a broad historical review and commentary based on the views of the CES members, with particular emphasis on tracing the lengthy record of advisory committee recommendations. Any individual topic could be the subject of an extended report in its own right. Indeed, extensive further reviews are already under way to that end. If the CES has succeeded in the task it has undertaken. This report will serve as a useful starting point for any such more intensive study. The report is divided into eight chapters: ( I ) an introduction, (2) the evolution of the MTPE, (3) its relationship to the USGCRP, (4) applications of earth observations data, (5) the role that smaller satellites can play in research and operational remote sensing, (6) earth system modeling and information systems, (7) a number of associated activities that contribute to the MTPE

  1. Multiple Observing Modes for Wide-field Optical Surveillance of GEO Space

    Science.gov (United States)

    McGraw, J.; Zimmer, P.; Ackermann, M.

    2016-09-01

    Very wide field of view optical sensors with silicon detectors are being used in multiple survey modes by J. T. McGraw and Associates to provide persistent, affordable surveillance of GEO space to faint limiting magnitudes. Examples include: classical staring mode with typical integration times of seconds provided by multiple co-directed sensors to provide a deep mosaic of tens of square degrees per exposure to faint limiting magnitude b) step-and-stare observations of several second integration time from which a continuous, overlapped, mosaicked image of GEO space can be provided time-delay and integrate (TDI) imagery obtained by driving the telescope in declination and stepping the telescope in the E-W direction, which produces repeated, overlapping (if desired), synoptic images of GEO space. With current 350 mm diameter optics, detection limits for concentrated observations (e.g. "neighborhood watch") detection limits of magnitude 18 are achieved, and for uncued survey the detection limits are fainter than magnitude 16. Each of these techniques can employ multiple telescopes to obtain search rates in excess of 1000 square degrees per hour, allowing complete uncued CONUS GEO surveillance to +/- 15 degrees latitude every two nighttime hours. With appropriate placement, sensors could provide complete coverage of GEO to these limiting magnitudes at the same survey rate. At each step of the development of this unique capability we discuss the fundamental underlying physical principals of optics, detectors, search modes and siting that enable this survey, a valuable adjunct to RF, radar, GEODSS and other optical surveys of GEO space.

  2. Hubble Space Telescope Observations of the HD 202628 Debris Disk

    Science.gov (United States)

    Krist, John E.; Stapelfeldt, Karl R.; Bryden, Geoffrey; Plavchan, Peter

    2012-01-01

    A ring-shaped debris disk around the G2V star HD 202628 (d = 24.4 pc) was imaged in scattered light at visible wavelengths using the coronagraphic mode of the Space Telescope Imaging Spectrograph on the Hubble Space Telescope. The ring is inclined by approx.64deg from face-on, based on the apparent major/minor axis ratio, with the major axis aligned along PA = 130deg. It has inner and outer radii (> 50% maximum surface brightness) of 139 AU and 193 AU in the northwest ansae and 161 AU and 223 AU in the southeast ((Delta)r/r approx. = 0.4). The maximum visible radial extent is approx. 254 AU. With a mean surface brightnesses of V approx. = 24 mag arcsec.(sup -2), this is the faintest debris disk observed to date in reflected light. The center of the ring appears offset from the star by approx.28 AU (deprojected). An ellipse fit to the inner edge has an eccentricity of 0.18 and a = 158 AU. This offset, along with the relatively sharp inner edge of the ring, suggests the influence of a planetary-mass companion. There is a strong similarity with the debris ring around Fomalhaut, though HD 202628 is a more mature star with an estimated age of about 2 Gyr. We also provide surface brightness limits for nine other stars in our study with strong Spitzer excesses around which no debris disks were detected in scattered light (HD 377, HD 7590, HD 38858, HD 45184, HD 73350, HD 135599, HD 145229, HD 187897, and HD 201219).

  3. Adapting a Planetary Science Observational Facility for Space Situational Awareness

    Science.gov (United States)

    Bland, P.; DFN Team

    2016-09-01

    The Desert Fireball Network (DFN) is designed to track meteoroids entering the atmosphere, determine pre-entry orbits (their origin in the solar system), and pinpoint fall positions for recovery by field teams. Fireball observatories are sited at remote dark-sky sites across Australia - logistics for power, sensor platforms, and data connection are in place. Each observatory is a fully autonomous unit, taking 36MP all-sky images (with fisheye lenses) throughout the night, capable of operating for 12 months in a harsh environment, and storing all imagery collected over that period. They are intelligent imaging systems, using neural network algorithms to recognize and report fireball events. An automated data reduction pipeline delivers orbital data and meteorite fall positions. Currently the DFN stands at 50 observing stations covering 2.5 million km2. A sub-set of the existing stations will be upgraded with a parallel camera package using 50mm prime lenses. Paired stations will allow triangulation. The high resolution array would deliver a Gpixel tiled image of the visible sky every 10 sec, at 20 arcsec resolution, with a limiting magnitude of 13 in a 10 sec snapshot. There are benefits in transient astronomy (optical flashes associated with gamma-ray bursts; flares from sources that generate ultra-high energy cosmic rays), and space situational awareness. The hardware upgrade would extend the resolution of the DFN into the V=11-12 magnitude range for objects in LEO, allowing us to observe significant activity during the terminator period. The result would be a wide field array, capable of triangulation, with a 3500km baseline enabling a larger terminator observing window.

  4. Observational study: microgravity testing of a phase-change reference on the International Space Station.

    Science.gov (United States)

    Topham, T Shane; Bingham, Gail E; Latvakoski, Harri; Podolski, Igor; Sychev, Vladimir S; Burdakin, Andre

    2015-01-01

    Orbital sensors to monitor global climate change during the next decade require low-drift rates for onboard thermometry, which is currently unattainable without on-orbit recalibration. Phase-change materials (PCMs), such as those that make up the ITS-90 standard, are seen as the most reliable references on the ground and could be good candidates for orbital recalibration. Space Dynamics Lab (SDL) has been developing miniaturized phase-change references capable of deployment on an orbital blackbody for nearly a decade. Improvement of orbital temperature measurements for long duration earth observing and remote sensing. To determine whether and how microgravity will affect the phase transitions, SDL conducted experiments with ITS-90 standard material (gallium, Ga) on the International Space Station (ISS) and compared the phase-change temperature with earth-based measurements. The miniature on-orbit thermal reference (MOTR) experiment launched to the ISS in November 2013 on Soyuz TMA-11M with the Expedition 38 crew and returned to Kazakhstan in March 2014 on the Soyuz TMA-10 spacecraft. MOTR tested melts and freezes of Ga using repeated 6-h cycles. Melt cycles obtained on the ground before and after launch were compared with those obtained on the ISS. To within a few mK uncertainty, no significant difference between the melt temperature of Ga at 1 g and in microgravity was observed.

  5. Multi-Wavelength Observations of the Soft Gamma Repeater SGR 1900+14 During its April 2001 Activation

    Science.gov (United States)

    Kouveliotou, C.; Tennant, A. F.; Woods, P.; Hurley, K.; Fender, R. P.; Garrington, S. T.; Patel, S. K.; Gogus, E.; Whitaker, Ann F. (Technical Monitor)

    2001-01-01

    The soft-gamma repeater SGR became active on 18 April 2001 after about a year of quiescence; it had remained at a very low state of activity since the fall of 1998, when it exhibited extraordinary flaring. We have observed the source in the gamma and X-rays with \\ulysses and \\chandra, and in the radio with MERLIN. We report here the confirmation of a two component X-ray spectrum (power law $+$ blackbody), indicating emission from the neutron star surface. We have determined that there is a dust halo surrounding the source that extends up to $\\gtrsim100^{\\prime\\prime}$ from the SGR center, which is due to the scattering in the Interstellar Medium.

  6. Observations and Impact Assessments of Extreme Space Weather Events

    Science.gov (United States)

    Baker, D. N.

    2007-05-01

    "Space weather" refers to conditions on the Sun, in the solar wind, and in Earth`s magnetosphere, ionosphere, and thermosphere. Activity on the Sun such as solar flares and coronal mass ejections can lead to high levels of radiation in space and can cause major magnetic storms at the Earth. Space radiation can come as energetic particles or as electromagnetic emissions. Adverse conditions in the near-Earth space environment can cause disruption of satellite operations, communications, navigation, and electric power distribution grids. This can lead to a variety of socioeconomic losses. Astronauts and airline passengers exposed to high levels of radiation are also at risk. Society`s vulnerability to space weather effects is an issue of increasing concern. We are dependent on technological systems that are becoming more susceptible to space weather disturbances. We also have a permanent human presence in space with the International Space Station and the President and NASA have expressed a desire to expand our human space activities with missions to the moon and Mars. This will make space weather of even greater concern in the future. In this talk I will describe many space weather effects and will describe some of the societal and economic impacts that extreme events have had.

  7. Present-day crustal deformation along the Magallanes-Fagnano Fault System in Tierra del Fuego from repeated GPS observations

    Science.gov (United States)

    Mendoza, L.; Perdomo, R.; Hormaechea, J. L.; Del Cogliano, D.; Fritsche, M.; Richter, A.; Dietrich, R.

    2011-03-01

    The present-day deformation of the earth crust in the Argentine part of Tierra del Fuego main island (southernmost South America) is here investigated based on repeated geodetic GPS observations. The island is traversed by the active transform boundary between the South American and Scotia tectonic plates, represented by the Magallanes-Fagnano fault system. Since 1993 a regional network comprising to date 29 GPS sites has been observed almost every year. The complete set of accumulated observations was processed using the Bernese GPS software and state-of-the-art processing strategies and models. The utilization of homogeneous GPS products resulting from a reprocessing of the global IGS network warrants a stable realization of a global reference frame. For each GPS site 3-D positions and linear velocities with error estimates were obtained. A strain analysis of the horizontal velocity components revealed the zones of major deformation activity. A 30-km-wide deformation belt centred on the main trace of the fault system was identified. This belt is bordered to the north (South America) and south (Scotia) by geodynamically stable zones, which move horizontally with a relative average velocity of 4.4 ± 0.6 (east) and -0.3 ± 0.4 (north) mm a-1. Within the deformation belt a maximum strain rate in the order of 0.25 μstrain per year has been detected. A pronounced change in the deformation style from transtension (east) to transpression (west) is observed. The area of predominating shortening of the crust coincides with a local rotation minimum and relative uplift. Throughout the period covered by the GPS observations the displacements and deformations occurred to be linear with time.

  8. A perspective about the total solar eclipse observation from future space settlements and a review of Indonesian space researches

    Science.gov (United States)

    Sastradipradja, D.; Dwivany, F. M.; Swandjaja, L.

    2016-11-01

    Viewing astronomy objects from space is superior to that from Earth due to the absence of terrestrial atmospheric disturbances. Since decades ago, there has been an idea of building gigantic spaceships to live in, i.e., low earth orbit (LEO) settlement. In the context of solar eclipse, the presuming space settlements will accommodate future solar eclipse chasers (amateur or professional astronomers) to observe solar eclipse from space. Not only for scientific purpose, human personal observation from space is also needed for getting aesthetical mental impression. Furthermore, since space science indirectly aids solar eclipse observation, we will discuss the related history and development of Indonesian space experiments. Space science is an essential knowledge to be mastered by all nations.

  9. Improvements in anatomy knowledge when utilizing a novel cyclical "Observe-Reflect-Draw-Edit-Repeat" learning process.

    Science.gov (United States)

    Backhouse, Mark; Fitzpatrick, Michael; Hutchinson, Joseph; Thandi, Charankumal S; Keenan, Iain D

    2017-01-01

    Innovative educational strategies can provide variety and enhance student learning while addressing complex logistical and financial issues facing modern anatomy education. Observe-Reflect-Draw-Edit-Repeat (ORDER), a novel cyclical artistic process, has been designed based on cognitivist and constructivist learning theories, and on processes of critical observation, reflection and drawing in anatomy learning. ORDER was initially investigated in the context of a compulsory first year surface anatomy practical (ORDER-SAP) at a United Kingdom medical school in which a cross-over trial with pre-post anatomy knowledge testing was utilized and student perceptions were identified. Despite positive perceptions of ORDER-SAP, medical student (n = 154) pre-post knowledge test scores were significantly greater (P learning methods (3.26, SD = ±2.25) than with ORDER-SAP (2.17, ±2.30). Based on these findings, ORDER was modified and evaluated in the context of an optional self-directed gross anatomy online interactive tutorial (ORDER-IT) for participating first year medical students (n = 55). Student performance was significantly greater (P  0.05) to those students without these characteristics. These findings will be of value to anatomy instructors seeking to engage students from diverse learning backgrounds in a research-led, innovative, time and cost-effective learning method, in the context of contrasting learning environments. Anat Sci Educ 10: 7-22. © 2016 American Association of Anatomists.

  10. A distance for probability spaces, and long-term values in Markov Decision Processes and Repeated Games

    CERN Document Server

    Renault, Jérôme

    2012-01-01

    Given a finite set $K$, we denote by $X=\\Delta(K)$ the set of probabilities on $K$ and by $Z=\\Delta_f(X)$ the set of Borel probabilities on $X$ with finite support. Studying a Markov Decision Process with partial information on $K$ naturally leads to a Markov Decision Process with full information on $X$. We introduce a new metric $d_*$ on $Z$ such that the transitions become 1-Lipschitz from $(X, \\|.\\|_1)$ to $(Z,d_*)$. In the first part of the article, we define and prove several properties of the metric $d_*$. Especially, $d_*$ satisfies a Kantorovich-Rubinstein type duality formula and can be characterized by using disintegrations. In the second part, we characterize the limit values in several classes of "compact non expansive" Markov Decision Processes. In particular we use the metric $d_*$ to characterize the limit value in Partial Observation MDP with finitely many states and in Repeated Games with an informed controller with finite sets of states and actions. Moreover in each case we can prove the ex...

  11. Observing Exoplanets with the James Webb Space Telescope

    Science.gov (United States)

    Clampin Mark

    2011-01-01

    The search for exoplanets and characterization of their properties has seen increasing success over the last few years. In excess of 500 exoplanets are known and Kepler has approx. 1000 additional candidates. Recently, progress has been made in direct imaging planets, both from the ground and in space. This presentation will discuss the history and current state of technology used for such discoveries, and highlight the new capabilities that will be enabled by the James Webb Space Telescope.

  12. Constraining Parameters in Pulsar Models of Repeating FRB 121102 with High-energy Follow-up Observations

    Science.gov (United States)

    Xiao, Di; Dai, Zi-Gao

    2017-09-01

    Recently, a precise (sub-arcsecond) localization of the repeating fast radio burst (FRB) 121102 led to the discovery of persistent radio and optical counterparts, the identification of a host dwarf galaxy at a redshift of z = 0.193, and several campaigns of searches for higher-frequency counterparts, which gave only upper limits on the emission flux. Although the origin of FRBs remains unknown, most of the existing theoretical models are associated with pulsars, or more specifically, magnetars. In this paper, we explore persistent high-energy emission from a rapidly rotating highly magnetized pulsar associated with FRB 121102 if internal gradual magnetic dissipation occurs in the pulsar wind. We find that the efficiency of converting the spin-down luminosity to the high-energy (e.g., X-ray) luminosity is generally much smaller than unity, even for a millisecond magnetar. This provides an explanation for the non-detection of high-energy counterparts to FRB 121102. We further constrain the spin period and surface magnetic field strength of the pulsar with the current high-energy observations. In addition, we compare our results with the constraints given by the other methods in previous works and expect to apply our new method to some other open issues in the future.

  13. Observing the Anthropocene from Space: Challenges and Needs

    Science.gov (United States)

    Burrows, John

    2016-07-01

    The rapid growth of human population since the industrial revolution has been coupled with a much increased standard of living and bountiful production of food. The dominant energy source sustaining this development has been fossil fuel combustion. However this has resulted in pollution which now spans all scales. There have significant impacts on air quality, water quality, stratospheric ozone and climate. The impacts can sudden and large and also slowly accumulate over time in the long term. The first decades of the space age resulted in pioneering efforts to establish adequate measurement capability. This process is continuing to evolve. Over the past two decades there have been a number of efforts to define the contribution and needs for a space segment which can separate anthropogenic form natural changes in the earth system. This talk introduces this topic of the use of the space segment to deconvolve change from anthropogenic activity and natural phenomena.

  14. First results of European VLBI radar observations of space objects

    CERN Document Server

    Molotov, I; Nechaeva, M; Dugin, N; Konovalenko, A A; Falkovich, I; Gorshenkov, Yu N; Liu, X; Volvach, A; Agapov, V; Pushkarev, A B; Titenko, V; Buttacio, S; Rumyantsev, V; Shmeld, I

    2004-01-01

    Since 1999 we carried out seven trial VLBI radar experiments under LFVN project. The aim of this work is to adjust new research technique for investigating the Solar system bodies (planets, asteroids, space debris). It is planned to obtain the information on their movement parameters, proper rotation and structure of surface. The transmitter of Evpatoria RT-70 sounded the space objects. Array of Bear Lakes RT-64, Noto RT-32, Urumqi RT-25, Simeiz RT-22 received the echo-signals. The data were processed with NIRFI-3 Mk-2 correlator in N. Novgorod, Russia and NRTV processor in Noto, Italy. The first results of these experiments are presented.

  15. First results of European VLBI radar observations of space objects

    Science.gov (United States)

    Molotov, I.; Tuccari, G.; Nechaeva, M.; Dugin, N.; Konovalenko, A.; Falkovich, I.; Gorshenkov, Y.; Liu, X.; Volvach, A.; Agapov, V.; Pushkarev, A.; Titenko, V.; Buttacio, S.; Rumyantsev, V.; Shmeld, I.

    Since 1999 we carried out seven trial VLBI radar experiments under LFVN project. The aim of this work is to adjust new research technique for investigating the Solar system bodies (planets, asteroids, space debris). It is planned to obtain the information on their movement parameters, proper rotation and structure of surface. The transmitter of Evpatoria RT-70 sounded the space objects. Array of Bear Lakes RT-64, Noto RT-32, Urumqi RT-25, Simeiz RT-22 received the echo-signals. The data were processed with NIRFI-3 Mk-2 correlator in N. Novgorod, Russia and NRTV processor in Noto, Italy. The first results of these experiments are presented. (astro-ph/0412694)

  16. Multipoint observations of plasma phenomena made in space by Cluster

    Science.gov (United States)

    Goldstein, M. L.; Escoubet, P.; Hwang, K.-Joo; Wendel, D. E.; Viñas, A.-F.; Fung, S. F.; Perri, S.; Servidio, S.; Pickett, J. S.; Parks, G. K.; Sahraoui, F.; Gurgiolo, C.; Matthaeus, W.; Weygand, J. M.

    2015-06-01

    Plasmas are ubiquitous in nature, surround our local geospace environment, and permeate the universe. Plasma phenomena in space give rise to energetic particles, the aurora, solar flares and coronal mass ejections, as well as many energetic phenomena in interstellar space. Although plasmas can be studied in laboratory settings, it is often difficult, if not impossible, to replicate the conditions (density, temperature, magnetic and electric fields, etc.) of space. Single-point space missions too numerous to list have described many properties of near-Earth and heliospheric plasmas as measured both in situ and remotely (see http://www.nasa.gov/missions/#.U1mcVmeweRY for a list of NASA-related missions). However, a full description of our plasma environment requires three-dimensional spatial measurements. Cluster is the first, and until data begin flowing from the Magnetospheric Multiscale Mission (MMS), the only mission designed to describe the three-dimensional spatial structure of plasma phenomena in geospace. In this paper, we concentrate on some of the many plasma phenomena that have been studied using data from Cluster. To date, there have been more than 2000 refereed papers published using Cluster data but in this paper we will, of necessity, refer to only a small fraction of the published work. We have focused on a few basic plasma phenomena, but, for example, have not dealt with most of the vast body of work describing dynamical phenomena in Earth's magnetosphere, including the dynamics of current sheets in Earth's magnetotail and the morphology of the dayside high latitude cusp. Several review articles and special publications are available that describe aspects of that research in detail and interested readers are referred to them (see for example, Escoubet et al. 2005 Multiscale Coupling of Sun-Earth Processes, p. 459, Keith et al. 2005 Sur. Geophys. 26, 307-339, Paschmann et al. 2005 Outer Magnetospheric Boundaries: Cluster Results, Space Sciences Series

  17. Earth scenes in polarized light observed from the Space Shuttle

    Science.gov (United States)

    Whitehead, Victor S.; Coulson, Kinsell L.

    1989-01-01

    By means of a pair of boresighted and synchronized cameras fitted with orthogonally oriented polarizing filters and carried aboard the Space Shuttle, a large number of polarized images of the earth's surface have been obtained from orbital altitude. Selected pairs of images, both in color and in black and white, have been digitized and computer-processed to yield analogous images in each of the three Stokes parameters necessary for characterizing the state of linear polarization of the emergent light. Many of the images show surface properties more distinctly in degree and plane of polarization than in simple intensity alone. It is believed that these are the first, and certainly the most extensive, set of polarized images of the earth ever obtained from space. Selected pairs of the images are presented here along with some early results of analysis.

  18. LISA Pathfinder: First steps to observing gravitational waves from space

    Science.gov (United States)

    LISA Pathfinder Collaboration

    2017-05-01

    LISA Pathfinder, the European Space Agency’s technology demonstrator mission for future spaceborne gravitational wave observatories, was launched on 3 December 2015, from the European space port of Kourou, French Guiana. After a short duration transfer to the final science orbit, the mission has been gathering science data since. This data has allowed the science community to validate the critical technologies and measurement principle for low frequency gravitational wave detection and thereby confirming the readiness to start the next generation gravitational wave observatories, such as LISA. This paper will briefly describe the mission, followed by a description of the science operations highlighting the performance achieved. Details of the various experiments performed during the nominal science operations phase can be found in accompanying papers in this volume.

  19. Stennis Space Center observes 2009 Energy Awareness Day

    Science.gov (United States)

    2009-01-01

    Stennis Space Center employees Maria Etheridge (l to r), Linda Sauland Maurice Prevost visit a Coast Electric Power Association display featuring energy-efficient light bulbs during 2009 Energy Awareness Day activities on Oct. 20. The exhibit was one of several energy-efficiency and energy-awareness displays on-site for employees to visit. Vendors included Mississippi Power Company, Coast Electric Power Association, Mississippi Development Authority - Energy Division,Jacobs FOSC Environmental, Southern Energy Technologies, and Siemens Building Technologies.

  20. The Transform between the space of observed values and the space of possible values of the parameter

    CERN Document Server

    Bityukov, S; Smirnova, V; Taperechkina, V

    2013-01-01

    In ref [math.ST/0411462] the notion of statistically dual distributions is introduced. The reconstruction of confidence density [AIP Conference Proceedings 803 (2005) 398] for the location parameter for several pairs of statistically dual distributions (Poisson and Gamma, normal and normal, Cauchy and Cauchy, Laplace and Laplace) in the case of single observation of the random variable is a unique. It allows to introduce the Transform between the space of observed values and the space of possible values of the parameter.

  1. An Integrated Management System of Multipoint Space Weather Observation

    Directory of Open Access Journals (Sweden)

    H Watanabe

    2013-03-01

    Full Text Available An outline of a planned system for the global space-weather monitoring network of NICT (National Institute of Information and Communications Technology is given. This system can manage data collection much more easily than our current system by installations of autonomous recovery, periodical state monitoring, and dynamic warning procedures. According to a provisional experiment using a network simulator, the new system will work under limited network conditions, e.g., a 160 msec delay, a 10 % packet loss rate, and a 500 Kbps bandwidth.

  2. Combining Solar Science and Asteroid Science with the Space Weather Observation Network (SWON)

    OpenAIRE

    Maiwald, Volker; Weiß, André; Jansen, Frank

    2011-01-01

    The peculiarity of space weather for Earth orbiting satellites, air traffic and power grids on Earth and especially the financial and operational risks posed by damage due to space weather, underline the necessity of space weather observation. The importance of such observations is even more increasing due to the impending solar maximum. In recognition of this importance we propose a mission architecture for solar observation as an alternative to already published mission plans like Solar Pro...

  3. OCEANSAT_2 : an Indian space mission devoted to Earth observation

    Science.gov (United States)

    Venkata Rao, M.; de Cosmo, V.; Vespe, F.

    The first OCEANSAT a satellite devoted to Ocean applications was launched in May 1999 and had a lifetime of 6 years It carried two Payloads the Ocean Color Monitor OCM and Multi-frequency Scanning Microwave Radiometer MSMR These payloads provided valuable data which were used for various applications helpful for India as well as by International users The main applications of the OCM were the identification of Potential Fishery Zones PFZ while from the sea surface field of temperatures got by the MSMR the prediction of Monsoon arrival The second OCEANSAT mission is exactly a follow on of the first but with improved releases of the payloads The OCM is 8-narrow Band multi-spectral camera with 360 m Resolution 1420 Kms Swath and 2 days revisiting time The scatterometer is a Ku-band 13 515GHz radar with V H polarization and works with two-beam conical scanning On last October a memorandum of Understanding between the Indian and the Italian qSpace Agencies ISRO ASI was signed just to enrich the mission with another payload developed by ASI the space-borne GPS receiver devoted to radio occultation ROSA The goals of the mission the payloads and their applications will be described in detail

  4. Observing and understanding the Earth system variations from space geodesy

    OpenAIRE

    Jin, Shuanggen; van Dam, Tonie; Wdowinski, Shimon

    2013-01-01

    The interaction and coupling of the Earth system components that include the atmosphere, hydrosphere, cryosphere, lithosphere, and other fluids in Earth's interior, influence the Earth's shape, gravity field and its rotation (the three pillars of geodesy). The effects of global climate change, such as sea level rise, glacier melting, and geoharzards, also affect these observables. However, observations and models of Earth's system change have large uncertainties due to the lack of direct high...

  5. High Fidelity Airborne Imaging System for Remote Observation of Space Launch/Reentry Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The utility of airborne remote observation of hypersonic reentry vehicles was demonstrated by the NASA Hypersonic Thermodynamic Infrared Measurement (HYTHIRM)...

  6. Observing the Impact of the Anthropocene from Space: the Evolution of Atmospheric Observation

    Science.gov (United States)

    Burrows, John P.

    2016-04-01

    From the Neolithic revolution to the industrial revolution over ~ 10 000 years, the earth's population rose from several millions to 1 Billion powered by energy from a mixture of biofuels, water and solar power and a limited amount of the combustion of coal. The industrial revolution began in the UK in the late 18th century, and has been fuelled by the combustion of fossil fuels, initially coal but then oil and gas. This has led to a dramatic rise in both the human population, now comprising over 7 Billion with more than 50% living in urban areas, and its standard of living. The expectation is that by 2050 population will be of the order of 10 Billion with 75% dwelling in urban areas. Anthropogenic activity has resulted in pollution from the local to the global scale, changes in land use, the destruction of stratospheric ozone, the modification of biogeochemical cycling, the destruction of species, ecosystems and ecosystem services and climate change. The earth has entered a new geological epoch the anthropocene. The observation of atmospheric composition provides a unique early warning of the natural and anthropogenic origins of change. Consistent and consolidated measurements from the local to the global scale are required to test our knowledge of the biogeochemical cycles, which determine atmospheric composition, and to assess and attribute accurately their modification by anthropogenic activity. To achieve global measurements of atmospheric constituents (trace gases, aerosol and cloud parameters) the SCIAMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY), Project was initiated in the early 1980s. This was the first passive remote sensing space based instrumentation, designed to make simultaneous contiguous measurements of the solar upwelling radiation at the top of the atmosphere from the ultraviolet to the shortwave infrared. The SCIAMACHY project resulted in measurements of the instruments GOME, originally called SCIA-mini, on ESA

  7. Information Content of Bistatic Lidar Observations of Aerosols from Space

    Science.gov (United States)

    Alexandrov, Mikhail D.; Mishchenko, Michael I.

    2017-01-01

    We present, for the first time, a quantitative retrieval error-propagation study for a bistatic high spectral resolution lidar (HSRL) system intended for detailed quasi-global monitoring of aerosol properties from space. Our results demonstrate that supplementing a conventional monostatic HSRL with an additional receiver flown in formation at a scattering angle close to 165 degrees dramatically increases the information content of the measurements and allows for a sufficiently accurate characterization of tropospheric aerosols. We conclude that a bistatic HSRL system would far exceed the capabilities of currently flown or planned orbital instruments in monitoring global aerosol effects on the environment and on the Earth's climate. We also demonstrate how the commonly used a priori 'regularization' methodology can artificially reduce the propagated uncertainties and can thereby be misleading as to the real retrieval capabilities of a measurement system.

  8. The first decade of RR Lyrae space photometric observations

    CERN Document Server

    Molnár, Lászlo

    2016-01-01

    Space-based photometric telescopes stirred up stellar astrophysics in the last decade, and RR Lyrae stars have not been an exception from that either. The long, quasi-continuous, high-precision data from MOST, CoRoT and Kepler revealed a wealth of new insights about this well-known variable class. One of the most surprising mysteries turned out to be the apparent omnipresence of a common additional mode in all RRd and RRc stars. Moreover, fundamental-mode stars seem to populate two distinct classes, one of which is characterized by the presence of additional modes and/or modulation, and another limited to strict single-mode pulsation. The presence of additional modes and multiple modulations in RRab stars allowed us to construct Petersen diagrams for these parameters: while the pulsation modes show clear structures according to period ratios, there seems to be no relation between the modulation periods themselves.

  9. Quiet but still bright: XMM-Newton observations of the soft gamma-ray repeater SGR 0526-66

    NARCIS (Netherlands)

    A. Tiengo; P. Esposito; S. Mereghetti; G.L. Israel; L. Stella; R. Turolla; S. Zane; N. Rea; D. Götz; M. Feroci

    2009-01-01

    SGR 0526-66 was the first soft gamma-ray repeater (SGR) from which a giant flare was detected in March 1979, suggesting the existence of magnetars, i.e. neutron stars powered by the decay of their extremely strong magnetic field. Since then, very little information has been obtained on this object,

  10. The First Simultaneous Microlensing Observations by Two Space telescopes

    DEFF Research Database (Denmark)

    Shvartzvald, Y.; Li, Z.; Udalski, A.

    2016-01-01

    Simultaneous observations of microlensing events from multiple locations allow for the breaking of degeneracies between the physical properties of the lensing system, specifically by exploring different regions of the lens plane and by directly measuring the “microlens parallax.” We report the di...

  11. Tropical sources and sinks of carbonyl sulfide observed from space

    Science.gov (United States)

    Glatthor, Norbert; Höpfner, Michael; Baker, Ian T.; Berry, Joe; Campbell, Elliott; Kawa, Stephan R.; Krysztofiak, Gisele; Sinnhuber, Björn-Martin; Stiller, Gabriele; Stinecipher, Jim; von Clarmann, Thomas

    2016-04-01

    According to current budget estimations the seasonal variation of carbonyl sulfide (COS) is governed by oceanic release and vegetation uptake. Its assimilation by plants is assumed to be similar to the photosynthetic uptake of CO2 but, contrary to the latter process, to be irreversible. Therefore COS has been suggested as co-tracer of the carbon cycle. Observations of COS, however, are sparse, especially in tropical regions. We use the comprehensive data set of spaceborne measurements of the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) to analyze its global distribution. Two major features are observed in the tropical upper troposphere around 250 hPa: enhanced amounts over the western Pacific and the Maritime Continent, peaking around 550 pptv in boreal summer, and a seasonally varying depletion of COS extending from tropical South America to Africa. The large-scale COS depletion, which in austral summer amounts up to -40 pptv as compared to the rest of the respective latitude band, has not been observed before and reveals the seasonality of COS uptake through tropical vegetation. The observations can only be reproduced by global models, when a large vegetation uptake and a corresponding increase in oceanic emissions as proposed in several recent publications is assumed.

  12. Space-based observation of volcanic iodine monoxide

    Science.gov (United States)

    Schönhardt, Anja; Richter, Andreas; Theys, Nicolas; Burrows, John P.

    2017-04-01

    Volcanic eruptions inject substantial amounts of halogens into the atmosphere. Chlorine and bromine oxides have frequently been observed in volcanic plumes from different instrumental platforms such as from ground, aircraft and satellites. The present study is the first observational evidence that iodine oxides are also emitted into the atmosphere during volcanic eruptions. Large column amounts of iodine monoxide, IO, are observed in satellite measurements following the major eruption of the Kasatochi volcano, Alaska, in 2008. The IO signal is detected in measurements made both by SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric CHartographY) on ENVISAT (Environmental Satellite) and GOME-2 (Global Ozone Monitoring Experiment-2) on MetOp-A (Meteorological Operational Satellite A). Following the eruption on 7 August 2008, strongly elevated levels of IO slant columns of more than 4 × 1013 molec cm-2 are retrieved along the volcanic plume trajectories for several days. The retrieved IO columns from the different instruments are consistent, and the spatial distribution of the IO plume is similar to that of bromine monoxide, BrO. Details in the spatial distribution, however, differ between IO, BrO and sulfur dioxide, SO2. The column amounts of IO are approximately 1 order of magnitude smaller than those of BrO. Using the GOME-2A observations, the total mass of IO in the volcanic plume injected into the atmosphere from the eruption of Kasatochi on 7 August 2008, is determined to be on the order of 10 Mg.

  13. FIREBall-2: Trailblazing observations of the space UV circumgalactic medium

    Science.gov (United States)

    Martin, Christopher

    and science strategies for a future space mission to map emission from CGM and IGM baryons. Its flights will continue to provide important training for the next generation of space astrophysicists working in UV and other wavelength instrumentation. Most importantly, FIREBall-2 will detect emission from the CGM of nearby galaxies, providing the first census of the density and kinematics of this material for low z galaxies and open-ing a new field of CGM science.

  14. Time Dependent Couplings as Observables in de Sitter Space

    CERN Document Server

    Kitamoto, Hiroyuki

    2014-01-01

    We summarize and expand our investigations concerning the soft graviton effects on microscopic matter dynamics in de Sitter space. The physical couplings receive IR logarithmic corrections which are sensitive to the IR cut-off at the one-loop level. The scale invariant spectrum in the gravitational propagator at the super-horizon scale is the source of the de Sitter symmetry breaking. The quartic scalar, Yukawa and gauge couplings become time dependent and diminish with time. In contrast, the Newton's constant increases with time. We clarify the physical mechanism behind these effects in terms of the conformal mode dynamics in analogy with 2d quantum gravity. We show that they are the inevitable consequence of the general covariance and lead to gauge invariant predictions. We construct a simple model in which the cosmological constant is self-tuned to vanish due to UV-IR mixing effect. We also discuss phenomenological implications such as decaying Dark Energy and SUSY breaking at the Inflation era. The quantu...

  15. MAXI: all-sky observation from the International Space Station

    CERN Document Server

    Mihara, Tatehiro; Matsuoka, Masaru; Tomida, Hiroshi; Ueno, Shiro; Negoro, Hitoshi; Yoshida, Atsumasa; Tsunemi, Hiroshi; Nakajima, Motoki; Ueda, Yoshihiro; Yamauchi, Makoto

    2014-01-01

    Monitor of All-sky X-ray Image (MAXI) is mounted on the International Space Station (ISS). Since 2009 it has been scanning the whole sky in every 92 minutes with ISS rotation. Due to high particle background at high latitude regions the carbon anodes of three GSC cameras were broken. We limit the GSC operation to low-latitude region around equator. GSC is suffering a double high background from Gamma-ray altimeter of Soyuz spacecraft. MAXI issued the 37-month catalog with 500 sources above ~0.6 mCrab in 4-10 keV. MAXI issued 133 to Astronomers Telegram and 44 to Gammaray burst Coordinated Network so far. One GSC camera had a small gas leak by a micrometeorite. Since 2013 June, the 1.4 atm Xe pressure went down to 0.6 atm in 2014 May 23. By gradually reducing the high voltage we keep using the proportional counter. SSC with X-ray CCD has detected diffuse soft X-rays in the all-sky, such as Cygnus super bubble and north polar spur, as well as it found a fast soft X-ray nova MAXI J0158-744. Although we operate C...

  16. Contrail observations from space using NOAA-AVHRR data

    Energy Technology Data Exchange (ETDEWEB)

    Mannstein, H. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere

    1997-12-31

    The infrared channels of the Advanced Very High Resolution Radiometer (AVHRR) onboard of the weather satellites of the NOAA series allow the detection of contrails. An automated detection scheme is described and tested against computer aided visual classifications by two experts. The algorithm seems to identify contrails within the satellite data with a skill comparable to the human observers. Clusters of contrails within the satellite images are connected to outline regions where the atmospheric properties are favourable for the existence of observable contrails. Air traffic data shows that, over Middle Europe at least, in the main flight levels most of these regions should be marked by detectable contrails. The mean areal coverage of these regions is estimated to be in the range of 10% to 20%, the cloud coverage by detected contrails was 0.9% in 60 AVHRR scenes covering Central Europe. (author) 3 refs.

  17. About death and dying: a space for observation

    Directory of Open Access Journals (Sweden)

    Ana Maria Yamaguchi Ferreira

    2013-10-01

    Full Text Available This article discusses thoughts and concepts about Palliative Care and Thanatology, sciences that deal with issues such as death and the dying process, aiming to broaden the already existing observations, analysis and discussions about the theme, in order to help the layman public as well as the health professionals, to handle death and the dying process in a more humanized and approachable way, considering that these are conditions that relate to each and every human being.  

  18. Space debris observational test with the Medicina-Evpatoria bistatic radar.

    Science.gov (United States)

    Pupillo, G.; Bartolini, M.; Cevolani, G.; Di Martino, M.; Falkovich, I.; Konovalenko, A. A.; Malevinskij, S.; Montebugnoli, S.; Nabatov, A.; Pluchino, S.; Salerno, E.; Schillirò, F.; Zoni, L.

    In the framework of the space debris monitoring program of the Italian Space Agency (ASI), the Italian Institute of Radioastronomy (IRA), the Turin Astronomical Observatory (OATO) and the Ukrainian Institute of Radioastronomy performed a space debris observational test by using the Medicina-Evpatoria bistatic radar. Several kinds of objects orbiting in LEO, MEO, GEO and HEO were selected as target in order to validate the hardware setup and new observational techniques. Echoes coming from small space debris were detected with an extremely high signal to noise ratio as well as still unknown orbiting objects were presumably discovered during the observations.

  19. MAXI: all-sky observation from the International Space Station

    Science.gov (United States)

    Mihara, Tatehiro; Sugizaki, Mutsumi; Matsuoka, Masaru; Tomida, Hiroshi; Ueno, Shiro; Negoro, Hitoshi; Yoshida, Atsumasa; Tsunemi, Hiroshi; Nakajima, Motoki; Ueda, Yoshihiro; Yamauchi, Makoto

    2014-07-01

    Monitor of All-sky X-ray Image (MAXI) is mounted on the International Space Station (ISS). Since 2009 it has been scanning the whole sky in every 92 minutes with ISS rotation. Due to high particle background at high latitude regions the carbon anodes of three GSC cameras were broken. We limit the GSC operation to low-latitude region around equator. GSC is suffering a double high background from Gamma-ray altimeter of Soyuz spacecraft. MAXI issued the 37-month catalog with 500 sources above ~0.6 mCrab in 4-10 keV. MAXI issued 133 to Astronomers Telegram and 44 to Gammaray burst Coordinated Network so far. One GSC camera had a small gas leak by a micrometeorite. Since 2013 June, the 1.4 atm Xe pressure went down to 0.6 atm in 2014 May 23. By gradually reducing the high voltage we keep using the proportional counter. SSC with X-ray CCD has detected diffuse soft X-rays in the all-sky, such as Cygnus super bubble and north polar spur, as well as it found a fast soft X-ray nova MAXI J0158-744. Although we operate CCD with charge-injection, the energy resolution is degrading. In the 4.5 years of operation MAXI discovered 6 of 12 new black holes. The long-term behaviors of these sources can be classified into two types of the outbursts, 3 Fast Rise Exponential Decay (FRED) and 3 Fast Rise and Flat Top (FRFT). The cause of types is still unknown.

  20. Asteroid observations with the Hubble Space Telescope and the Space Infrared Telescope Facility

    Science.gov (United States)

    Zellner, B.; Wells, Eddie N.; Chapman, Clark R.; Cruikshank, D. P.

    1989-01-01

    The ways that the asteroids can be studied with the Hubble Space Telescope (HST) and the Space Infrared Telescope Facility (SIRTF) are examined. Spectrophotometry of asteroids and the study of asteroid surfaces, shape, spins, configuration, normal reflectance, and limb darkening of asteroids using the HST are addressed along with the detection of asteroid satellites and the discovery of small asteroids using the HST. The relation of the HST to its ground system is described, as are the spectrophotometric instruments of the HST. Imaging with the HST using the Faint Object Camera and the Wide Field and Planetary Camera is examined. Finally, the SIRTF observatory, instrumentation, and capabilities for solar system science are discussed.

  1. An Efficient Optical Observation Ground Network is the Fundamental basis for any Space Based Debris Observation Segment

    Science.gov (United States)

    Cibin, L.; Chiarini, M.; Annoni, G.; Milani, A.; Bernardi, F.; Dimare, L.; Valsecchi, G.; Rossi, A.; Ragazzoni, R.; Salinari, P.

    2013-08-01

    A matter which is strongly debated in the SSA Community, concerns the observation of Space Debris from Space [1]. This topic has been preliminary studied by our Team for LEO, MEO and GEO orbital belts, allowing to remark a fundamental concept, residing in the fact that to be suitable to provide a functionality unavailable from ground in a cost to performance perspective, any Space Based System must operate in tight collaboration with an efficient Optical Ground Observation Network. In this work an analysis of the different functionalities which can be implemented with this approach for every orbital belt is illustrated, remarking the different achievable targets in terms of population size as a function of the observed orbits. Further, a preliminary definition of the most interesting missions scenarios, together with considerations and assessments on the observation strategy and P/L characteristics are presented.

  2. Model and observed seismicity represented in a two dimensional space

    Directory of Open Access Journals (Sweden)

    M. Caputo

    1976-06-01

    Full Text Available In recent years theoretical seismology lias introduced
    some formulae relating the magnitude and the seismic moment of earthquakes
    to the size of the fault and the stress drop which generated the
    earthquake.
    In the present paper we introduce a model for the statistics of the
    earthquakes based on these formulae. The model gives formulae which
    show internal consistency and are also confirmed by observations.
    For intermediate magnitudes the formulae reproduce also the trend
    of linearity of the statistics of magnitude and moment observed in all the
    seismic regions of the world. This linear trend changes into a curve with
    increasing slope for large magnitudes and moment.
    When a catalogue of the magnitudes and/or the seismic moment of
    the earthquakes of a seismic region is available, the model allows to estimate
    the maximum magnitude possible in the region.

  3. Simulations and Tests of Prototype Antenna System for Low Frequency Radio Experiment (LORE) Space Payload for Space Weather Observations

    Science.gov (United States)

    Pethe, Kaiwalya; Galande, Shridhar; Jamadar, Sachin; Mahajan, S. P.; Patil, R. A.; Joshi, B. C.; Manoharan, P. K.; Roy, Jayashree; Kate, G.

    2016-03-01

    Low frequency Radio Experiment (LORE) is a proposed space payload for space weather observations from space, operating between few kHz to 30 MHz. This paper presents preliminary design and practical implementation of LORE antenna systems, which consist of three mutually orthogonal mono-poles. Detailed computational electromagnetic simulations, carried out to study the performance of the antenna systems, are presented followed up by laboratory tests of the antennas as well as radiation tests with a long range test range, designed for this purpose. These tests form the first phase of the design and implementation of the full LORE prototype later in the year.

  4. Observing phytoplankton physiology and ocean ecosystem structure from space

    Science.gov (United States)

    Schultz, Patrick

    Changes in ocean circulation in response to anthropogenic climate change affect ocean biology on a global scale. Based on a previously published empirical model that links ocean circulation to chlorophyll and chlorophyll to primary production, I predict an increase in primary production of 10--27% at the end of the 23rd century under four times pre-industrial atmospheric CO 2. The uncertainty in this prediction largely stems from the reliance on chlorophyll as the only model constraint. Chlorophyll concentrations are difficult to interpret, as they depend on phytoplankton biomass and cellular pigmentation, which adjusts to growth conditions. The objective of this thesis is to bridge the gap between laboratory-based knowledge of physiological adjustments to growth conditions and global satellite observations to reduce ambiguities in the interpretation of chlorophyll concentrations on a global scale. Satellite estimates of phytoplankton carbon and the chlorophyll to carbon ratio (Chl:C), a measure of pigmentation, are the foundation of this work. My main contribution is a re-evaluation of chlorophyll variability in the eastern subarctic Pacific, which updates the old paradigm for seasonal phytoplankton dynamics in this iron-limited region. In contrast to previous studies, I conclude that the consistently low chlorophyll concentrations are caused by a suppression of Chl:C by iron stress, rather than by reduced accumulation of phytoplankton biomass. Field observations during iron enrichment experiments and model simulations confirm that the satellite-observed suppression of Chl:C is consistent with physiological adjustments to low iron. On a global scale, I analyze how phytoplankton biomass and pigmentation interact to yield the spatial structure in surface chlorophyll and I employ a mechanistic photoacclimation model to diagnose the contributions of light, nutrients and temperature to the spatial structure in Chl:C. I further argue that the temporal variability of

  5. Microwave atmospheric sounder for earth limb observations from space

    Science.gov (United States)

    The Microwave Atmospheric Sounder (MAS) experiment which will be performed from a Spacelab pallet on board the Shuttle to study the dynamic structure of the mesosphere and stratosphere is described. The MAS package is the 4th mode of the microwave remote sensing experiment and comprises a SAR, a frequency scatterometer, and a passive radiometer. An elevation scan mode will involve observing through the elevation angle range of 10-16 deg at a constant velocity of 1.25 deg/sec. In a pointing mode, the pallet will operate at a fixed angle which can be changed by telemetered command to within 0.04 deg accuracy. A parabolic antenna receives the earth limb radiation at 62, 184, and 204 GHz. Radiometers down-convert the signal to around 10 GHz for spectral analysis based on chirp compressive receivers with 138 channels, each having 10 bit resolution.

  6. Plasma density fluctuations observed during Space Shuttle Orbiter water releases

    Science.gov (United States)

    Pickett, J. S.; D'Angelo, N.; Kurth, W. S.

    1989-01-01

    Observations by the Langmuir probe on the Plasma Diagnostics Package flown as part of the Spacelab 2 mission in the summer of 1985 show a strong increase in the level of turbulence near the Shuttle Orbiter during operations in which liquid water is released. The spectrum of the plasma density fluctuations peaks at the lowest frequencies measured (a few Hz) and extends up to a few kHz, near the lower hybrid frequency. Two potential mechanisms for generating the plasma turbulence are suggested which are both based on the production of water ions as a result of charge exchange with the ambient oxygen ions in the ionosphere. The first mechanism proposed is the ion-plasma instability which arises from the drift of the contaminant with respect to the ambient oxygen ions. The other mechanism proposed is the Ott-Farley instability, which is a result of the ring distribution formed by the 'pick-up' water ions.

  7. Observing quantum gravity in asymptotically AdS space

    Science.gov (United States)

    Emelyanov, Slava

    2015-12-01

    The question is studied of whether an observer can discover quantum gravity in the semiclassical regime. It is shown that it is indeed possible to probe a certain quantum gravity effect by employing an appropriately designed detector. The effect is related to the possibility of having topologically inequivalent geometries in the path-integral approach at the same time. A conformal field theory (CFT) state which is expected to describe the eternal anti-de Sitter (AdS) black hole in the large-N limit is discussed. It is argued under certain assumptions that the black hole boundary should be merely a patch of the entire AdS boundary. This leads then to a conclusion that that CFT state is the ordinary CFT vacuum restricted to that patch. If existent, the bulk CFT operators can behave as the ordinary semiclassical quantum field theory in the large-N limit in the weak sense.

  8. Intermediate CAG repeat expansion in the ATXN2 gene is a unique genetic risk factor for ALS--a systematic review and meta-analysis of observational studies.

    Directory of Open Access Journals (Sweden)

    Ming-Dong Wang

    Full Text Available Amyotrophic lateral sclerosis (ALS is a rare degenerative condition of the motor neurons. Over 10% of ALS cases are linked to monogenic mutations, with the remainder thought to be due to other risk factors, including environmental factors, genetic polymorphisms, and possibly gene-environmental interactions. We examined the association between ALS and an intermediate CAG repeat expansion in the ATXN2 gene using a meta-analytic approach. Observational studies were searched with relevant disease and gene terms from MEDLINE, EMBASE, and PsycINFO from January 2010 through to January 2014. All identified articles were screened using disease terms, gene terms, population information, and CAG repeat information according to PRISMA guidelines. The final list of 17 articles was further evaluated based on the study location, time period, and authors to exclude multiple usage of the same study populations: 13 relevant articles were retained for this study. The range 30-33 CAG repeats in the ATXN2 gene was most strongly associated with ALS. The meta-analysis revealed that the presence of an intermediate CAG repeat (30-33 in the ATXN2 gene was associated with an increased risk of ALS [odds ratio (OR = 4.44, 95%CI: 2.91-6.76] in Caucasian ALS patients. There was no significant difference in the association of this CAG intermediate repeat expansion in the ATXN2 gene between familial ALS cases (OR = 3.59, 1.58-8.17 and sporadic ALS cases (OR = 3.16, 1.88-5.32. These results indicate that the presence of intermediate CAG repeat expansion in the ATXN2 gene is a specific genetic risk factor for ALS, unlike monogenic mutations with an autosomal dominant transmission mode, which cause a more severe phenotype of ALS, with a higher prevalence in familial ALS.

  9. Intermediate CAG repeat expansion in the ATXN2 gene is a unique genetic risk factor for ALS--a systematic review and meta-analysis of observational studies.

    Science.gov (United States)

    Wang, Ming-Dong; Gomes, James; Cashman, Neil R; Little, Julian; Krewski, Daniel

    2014-01-01

    Amyotrophic lateral sclerosis (ALS) is a rare degenerative condition of the motor neurons. Over 10% of ALS cases are linked to monogenic mutations, with the remainder thought to be due to other risk factors, including environmental factors, genetic polymorphisms, and possibly gene-environmental interactions. We examined the association between ALS and an intermediate CAG repeat expansion in the ATXN2 gene using a meta-analytic approach. Observational studies were searched with relevant disease and gene terms from MEDLINE, EMBASE, and PsycINFO from January 2010 through to January 2014. All identified articles were screened using disease terms, gene terms, population information, and CAG repeat information according to PRISMA guidelines. The final list of 17 articles was further evaluated based on the study location, time period, and authors to exclude multiple usage of the same study populations: 13 relevant articles were retained for this study. The range 30-33 CAG repeats in the ATXN2 gene was most strongly associated with ALS. The meta-analysis revealed that the presence of an intermediate CAG repeat (30-33) in the ATXN2 gene was associated with an increased risk of ALS [odds ratio (OR) = 4.44, 95%CI: 2.91-6.76)] in Caucasian ALS patients. There was no significant difference in the association of this CAG intermediate repeat expansion in the ATXN2 gene between familial ALS cases (OR = 3.59, 1.58-8.17) and sporadic ALS cases (OR = 3.16, 1.88-5.32). These results indicate that the presence of intermediate CAG repeat expansion in the ATXN2 gene is a specific genetic risk factor for ALS, unlike monogenic mutations with an autosomal dominant transmission mode, which cause a more severe phenotype of ALS, with a higher prevalence in familial ALS.

  10. Clinical Observation on 46 Cases of Infantile Repeated Respiratory Tract Infection Treated by Mild-Moxibustion over Acupoints on Back

    Institute of Scientific and Technical Information of China (English)

    龙训; 常奇; 寿琼

    2001-01-01

    @@Repeated respiratory tract infection is a frequently-occurring disease during childhood. At present, western medicine doctors generally adopt anti-infectives and immunomodulators to treat the disease, while traditional Chinese medicine doctors mainly administer decoction of Chinese herbs. The authors treated 46 cases of repeated respiratory tract infection from March 1990 to April 1996 by applying mild-moxibustion over points on the back with satisfactory therapeutic results. A report follows. Clinical Data All the 86 cases were outpatients in our hospital with duration of common cold for over 10 days and characterized by relapse of respiratory tract infection. There were over 7-time relapse of respiratory tract infection on each case within a year. Eighty-six cases were randomly divided into treatment group (46 cases) and control group (40 cases). Of the 46 cases in the treatment group, 22 were boys and 24 girls. 17 cases (36.9%) were 6 months to 4 years old, 18 (39.1%) 4 to 6 years, and 11 (23.9%) 6 to 12 years. Among the 40 cases in the control group, 19 cases were boys and 21 girls.

  11. Clinical Observation on Termination of Early Pregnancy of 213 Cases after Caesarian Section with Repeated Use of Mifepristone and Misoprostol

    Institute of Scientific and Technical Information of China (English)

    高佩佩; 汪平

    1999-01-01

    Objective To investigate the efficacy and safety in women after caesarian section for termination of early pregnancies by treatment, or repeated treatment with mifepristone and misoprostot.Subjects and Methods A total of 213 pregnant women with amenorrhea of 34-69d after caesarian section who asked for medical abortion were recruited,including 63 cases undergoing their second medical abortion.A total amount of mi feprisstone of 150 mg given in separate doses(25 mg×4 and 50 mg at the first time)was administered orally within 3d, followed by misoprostot of 0.6 mg orally in the morning of d 3.Results The complete abortion rate was 92.5%,incomplete abortion was 4.7% and failure was 2.8%.Conclusion The sequential use of mifepristone and misoprostol could be successfully and repeatedly used for induced abortion in those women with a caesarian section histo-ry.Its efficacy was similar to that for ordinary population.Its safety and effec-tiveness were satisfactory.

  12. The role of SANSA's geomagnetic observation network in space weather monitoring: A review

    Science.gov (United States)

    Kotzé, P. B.; Cilliers, P. J.; Sutcliffe, P. R.

    2015-10-01

    Geomagnetic observations play a crucial role in the monitoring of space weather events. In a modern society relying on the efficient functioning of its technology network such observations are important in order to determine the potential hazard for activities and infrastructure. Until recently, it was the perception that geomagnetic storms had no or very little adverse effect on radio communication and electric power infrastructure at middle- and low-latitude regions like southern Africa. The 2003 Halloween storm changed this perception. In this paper we discuss the role of the geomagnetic observation network operated by the South African National Space Agency (SANSA) in space weather monitoring. The primary objective is to describe the geomagnetic data sets available to characterize and monitor the various types of solar-driven disturbances, with the aim to better understand the physics of these processes in the near-Earth space environment and to provide relevant space weather monitoring and prediction.

  13. Using and Experiencing the Academic Library: A Multisite Observational Study of Space and Place

    Science.gov (United States)

    May, Francine; Swabey, Alice

    2015-01-01

    This study examines how students are using academic library spaces and the role these spaces are playing in the campus community. Data were collected on five campuses (two community colleges, two undergraduate universities, and one technical institute) via observational seating sweeps and questionnaires. The study found remarkably similar usage…

  14. Large micro-mirror arrays: key components in future space instruments for Universe and Earth Observation

    Directory of Open Access Journals (Sweden)

    Zamkotsian Frederic

    2015-01-01

    Full Text Available In future space missions for Universe and Earth Observation, scientific return could be optimized using MOEMS devices. Micro-mirror arrays are used for designing new generation of instruments, multi-object spectrographs in Universe Observation and programmable wide field spectrographs in Earth Observation. Mock-ups have been designed and built for both applications and they show very promising results.

  15. An observer for a deployable antenna. [for large space structure flight experiment

    Science.gov (United States)

    Waites, H. B.

    1981-01-01

    An observer is derived for use on an Orbiter-Deployable Antenna configuration. The unique feature of this observer design for this flight experiment is that all the plant inputs are not required to be directly accessible for the observer to ferret out the system states. The observer uses state and rate of the state information to reconstruct the plant states. Results are presented which show how effectively this observer design works for this large space structure flight experiment.

  16. Design and Development of the Observation and Analysis of Smectic Islands in Space Experiment

    Science.gov (United States)

    Hall, Nancy Rabel; Tin, Padetha; Sheehan, C. C.; Stannarius, R.; Trittel, T.; Clark, N.; Maclennan, J.; Glaser, M.; Park, C.

    2012-01-01

    The primary objective of Observation and Analysis of Smectic Islands in Space (OASIS) experiment is to exploit the unique characteristics of freely suspended liquid crystals in a microgravity environment to advance the understanding of fluid state physics

  17. Ukrainian network of Optical Stations for man-made space objects observation

    Science.gov (United States)

    Sybiryakova, Yevgeniya

    2016-07-01

    The Ukrainian Network of Optical Stations (UNOS) for man-made objects research was founded in 2012 as an association of professional astronomers. The main goals of network are: positional and photometric observations of man-made space objects, calculation of orbital elements, research of shape and period of rotation. The network consists of 8 stations: Kiev, Nikolaev, Odesa, Uzhgorod, Lviv, Yevpatoriya, Alchevsk. UNOS has 12 telescopes for observation of man-made space objects. The new original methods of positional observation were developed for optical observation of geosynchronous and low earth orbit satellites. The observational campaigns of LEO satellites held in the network every year. The numerical model of space object motion, developed in UNOS, is using for orbit calculation. The results of orbital elements calculation are represented on the UNOS web-site http://umos.mao.kiev.ua/eng/. The photometric observation of selected objects is also carried out in network.

  18. Observing Ultra High Energy Cosmic Particles from Space: SEUSO, the Super Extreme Universe Space Observatory Mission

    CERN Document Server

    Santangelo, Andrea

    2009-01-01

    The experimental search for ultra high energy cosmic messengers, from $E\\sim 10^{19}$ eV to beyond $E\\sim 10^{20}$ eV, at the very end of the known energy spectrum, constitutes an extraordinary opportunity to explore a largely unknown aspect of our universe. Key scientific goals are the identification of the sources of ultra high energy particles, the measurement of their spectra and the study of galactic and local intergalactic magnetic fields. Ultra high energy particles might, also, carry evidence of unknown physics or of exotic particles relics of the early universe. To meet this challenge a significant increase in the integrated exposure is required. This implies a new class of experiments with larger acceptances and good understanding of the systematic uncertainties. Space based observatories can reach the instantaneous aperture and the integrated exposure necessary to systematically explore the ultra high energy universe. In this paper, after briefly summarising the science case of the mission, we desc...

  19. Observing the Calving Dynamics of Breiðamerkurjökull, Iceland, with Repeat UAV Aerial Photogrammetry

    Science.gov (United States)

    Jarosch, A. H.

    2014-12-01

    Since the summer of 2014, a cost-effective, fixed-wing UAV platform is used to map changes at the calving front of Breiðamerkurjökull, one of the largest outlet-glaciers of Vatnajökull, Iceland. The utilized wide angle camera (21 mm equivalent) delivers aerial images with a ground pixel resolution of approximately 18 cm, which are subsequently combined to digital elevation models (DEMs) mapping the calving front. Ground control points in the study area, measured with L1 phase GNSS receivers, are used to geo-locate the produced DEMs and ensure high quality co-registration between subsequent data sets. The 2 m wing span UAV platform is capable of 40 - 60 minutes of autonomous flight, guided by an open-source, open-hardware autopilot system (pixhawk.org) and thus can map rather large areas of the calving glacier. I will present results from the 2014 field season during which the calving front of Breiðamerkurjökull has been mapped repeatedly with data acquisition intervals ranging from hours to weeks. A lidar dataset from 2011 of the study region is used to validate the acquired DEM data and accuracy/precision statistics will be presented. I will also detail the UAV platform design, including instrumentation and flight mission planning.

  20. Observing floods from space: Experience gained from COSMO-SkyMed observations

    Science.gov (United States)

    Pierdicca, N.; Pulvirenti, L.; Chini, M.; Guerriero, L.; Candela, L.

    2013-03-01

    The COSMO-SkyMed mission offers a unique opportunity to obtain all weather radar images characterized by short revisit time, thus being useful for flood evolution mapping. The COSMO-SkyMed system has been activated several times in the last few years in occasion of flood events all over the world in order to provide very high resolution X-band SAR images useful for flood detection purposes. This paper discusses the major outcomes of the experience gained, within the framework of the OPERA Pilot Project funded by the Italian Space Agency, from using COSMO-SkyMed data for the purpose of near real time generation of flood maps. A review of the mechanisms which determine the imprints of the inundation on the radar images and of the fundamental simulation tools able to predict these imprints and help image interpretation is provided. The approach developed to process the data and to generate the flood maps is also summarized. Then, the paper illustrates the experience gained with COSMO-SkyMed by describing and discussing a number of significant examples. These examples demonstrate the potential of the COSMO-SkyMed system and the suitability of the approach developed for generating the final products, but they also highlight some critical aspects that require further investigations to improve the reliability of the flood maps.

  1. Repeating the errors of our parents? Family-of-origin spouse violence and observed conflict management in engaged couples.

    Science.gov (United States)

    Halford, W K; Sanders, M R; Behrens, B C

    2000-01-01

    Based on a developmental social learning analysis, it was hypothesized that observing parental violence predisposes partners to difficulties in managing couple conflict. Seventy-one engaged couples were assessed on their observation of parental violence in their family of origin. All couples were videotaped discussing two areas of current relationship conflict, and their cognitions during the interactions were assessed using a video-mediated recall procedure. Couples in which the male partner reported observing parental violence (male-exposed couples) showed more negative affect and communication during conflict discussions than couples in which neither partner reported observing parental violence (unexposed couples). Couples in which only the female partner reported observing parental violence (female-exposed couples) did not differ from unexposed couples in their affect or behavior. Female-exposed couples reported more negative cognitions than unexposed couples, but male-exposed couples did not differ from unexposed couples in their reported cognitions.

  2. Fixed-flexion knee radiography using a new positioning device produced highly repeatable measurements of joint space width: ELSA-Brasil Musculoskeletal Study (ELSA-Brasil MSK).

    Science.gov (United States)

    Telles, Rosa Weiss; Costa-Silva, Luciana; Machado, Luciana A C; Reis, Rodrigo Citton Padilha Dos; Barreto, Sandhi Maria

    To describe the performance of a non-fluoroscopic fixed-flexion PA radiographic protocol with a new positioning device, developed for the assessment of knee osteoarthritis (OA) in Brazilian Longitudinal Study of Adult Health Musculoskeletal Study (ELSA-Brasil MSK). A test-retest design including 19 adults (38 knee images) was conducted. Feasibility of the radiographic protocol was assessed by image quality parameters and presence of radioanatomic alignment according to intermargin distance (IMD) values. Repeatability was assessed for IMD and joint space width (JSW) measured at three different locations. Approximately 90% of knee images presented excellent quality. Frequencies of nearly perfect radioanatomic alignment (IMD ≤1mm) ranged from 29% to 50%, and satisfactory alignment was found in up to 71% and 76% of the images (IMD ≤1.5mm and ≤1.7mm, respectively). Repeatability analyses yielded the following results: IMD [SD of mean difference=1.08; coefficient of variation (%CV)=54.68%; intraclass correlation coefficient (ICC) (95%CI)=0.59 (0.34-0.77)]; JSW [SD of mean difference=0.34-0.61; %CV=4.48%-9.80%; ICC (95%CI)=0.74 (0.55-0.85)-0.94 (0.87-0.97)]. Adequately reproducible measurements of IMD and JSW were found in 68% and 87% of the images, respectively. Despite the difficulty in achieving consistent radioanatomic alignment between subsequent radiographs in terms of IMD, the protocol produced highly repeatable JSW measurements when these were taken at midpoint and 10mm from the medial extremity of the medial tibial plateau. Therefore, measurements of JSW at these locations can be considered adequate for the assessment of knee OA in ELSA-Brasil MSK. Copyright © 2016. Published by Elsevier Editora Ltda.

  3. CEOS Contributions to Informing Energy Management and Policy Decision Making Using Space-Based Earth Observations

    Science.gov (United States)

    Eckman, Richard S.

    2009-01-01

    Earth observations are playing an increasingly significant role in informing decision making in the energy sector. In renewable energy applications, space-based observations now routinely augment sparse ground-based observations used as input for renewable energy resource assessment applications. As one of the nine Group on Earth Observations (GEO) societal benefit areas, the enhancement of management and policy decision making in the energy sector is receiving attention in activities conducted by the Committee on Earth Observation Satellites (CEOS). CEOS has become the "space arm" for the implementation of the Global Earth Observation System of Systems (GEOSS) vision. It is directly supporting the space-based, near-term tasks articulated in the GEO three-year work plan. This paper describes a coordinated program of demonstration projects conducted by CEOS member agencies and partners to utilize Earth observations to enhance energy management end-user decision support systems. I discuss the importance of engagement with stakeholders and understanding their decision support needs in successfully increasing the uptake of Earth observation products for societal benefit. Several case studies are presented, demonstrating the importance of providing data sets in formats and units familiar and immediately usable by decision makers. These projects show the utility of Earth observations to enhance renewable energy resource assessment in the developing world, forecast space-weather impacts on the power grid, and improve energy efficiency in the built environment.

  4. Tachyphylaxis associated with repeated epidural injections of lidocaine is not related to changes in distribution or the rate of elimination from the epidural space

    Energy Technology Data Exchange (ETDEWEB)

    Mogensen, T.; Simonsen, L.; Scott, N.B.; Henriksen, J.H.; Kehlet, H. (Univ. of Copenhagen (Denmark))

    1989-08-01

    The relationship between tachyphylaxis (measured as a decrease in the rate of regression of sensory levels of analgesia) during repeated epidural injections of lidocaine and both the distribution of lidocaine within the epidural space (as measured by spread of simultaneous injection of the tracer technetium-99m diethylenetriaminepentaacetate (99mTc-DTPA)) and elimination of lidocaine from the epidural space (as measured by serum concentrations of lidocaine) was investigated in 18 patients undergoing minor surgery during lumbar epidural analgesia. Twelve patients received four injections of 20 mL of 2% lidocaine at 2-hr intervals. Epidural distribution was assessed by injection of 99mTc-DTPA diluted in saline on the preoperative day and diluted in an equal volume of 2% lidocaine on the morning before surgery and again after the fourth injection of lidocaine 6 hr later. The distribution of 99mTc-DTPA in the epidural space was unchanged during the three measurements despite significant tachyphylaxis in both sensory analgesia and motor blockade (11 of 12 patients had sensory analgesia 2 hr after the first injection in contrast to only 3 of 12 patients during the third injection). In another six patients 20 mL of 2% lidocaine were injected three times at 2-hr intervals before surgery, with measurements of serum concentrations of lidocaine after the first and last injections. Despite tachyphylaxis (no patient had sensory analgesia 2 hr after the third injection), there was no difference in the rate of disappearance of lidocaine from the epidural space as assessed by plasma lidocaine concentration curves during the first and third injection (0.5 +/- 0.1 and 0.3 +/- 0.04 microgram.mL-1.min-1, respectively).

  5. Coordinated observations using the world largest low-frequency radio telescopes and space misiions

    Science.gov (United States)

    Konovalenko, A. A.; Zarka, Ph.; Kolyadin, V. L.; Zakharenko, V. V.; Stepkin, S. V.; Panchenko, M.; Lecacheux, A.; Rucker, H. O.; Fischer, G.; Ulyanov, O. M.; Melnik, V. N.; Litvinenko, G. V.; Sidorchuk, M. A.; Bubnov, I. N.; Vasilyeva, Ya. Yu.; Bojko, A. I.; Shaposhnikov, V.; Mann, G.; Kalinichenko, N. N.; Falkovich, I. S.; Koval, A. A.; Mylostna, K.; Pylaev, O. S.; Shepelev, V. A.; Reznik, A. P.

    2013-09-01

    The positive possibilities of astrophysical objects studies(including the Solar system investigations) using coordinated observations with the largest existing and coming low frequency radio telescopes are shown. The observations of the Sun, Jupiter, Saturn, ant others with UTR-2, URAN, NDA radio telescopes, and WIND, Cassini and STEREO space missions at frequencies lower than 40 MHz have been carried out.

  6. Observer homogeneity in the histologic diagnosis of Helicobacter pylori. Latent class analysis, kappa coefficient, and repeat frequency

    DEFF Research Database (Denmark)

    Christensen, A H; Gjørup, T; Hilden, J;

    1992-01-01

    that uncertain statements were less frequently (61%) confirmed than were certain ones (85%). It is concluded that observer homogeneity is only moderate with regard to the histologic diagnosis of H. pylori, which should be considered both in daily clinical routine and in scientific studies. Disagreement between...

  7. Relative pointing offset analysis of calibration targets with repeated observations with Herschel-SPIRE Fourier-Transform Spectrometer

    CERN Document Server

    Valtchanov, Ivan; Polehampton, Edward; Benielli, Dominique; Fulton, Trevor; Imhof, Peter; Konopczynski, Tomasz; Lim, Tanya; Lu, Nanyao; Marchili, Nicola; Naylor, David; Swinyard, Bruce

    2014-01-01

    We present a method to derive the relative pointing offsets for SPIRE Fourier-Transform Spectrometer (FTS) solar system object (SSO) calibration targets, which were observed regularly throughout the Herschel mission. We construct ratios of the spectra for all observations of a given source with respect to a reference. The reference observation is selected iteratively to be the one with the highest observed continuum. Assuming that any pointing offset leads to an overall shift of the continuum level, then these ratios represent the relative flux loss due to mispointing. The mispointing effects are more pronounced for a smaller beam, so we consider only the FTS short wavelength array (SSW, 958-1546 GHz) to derive a pointing correction. We obtain the relative pointing offset by comparing the ratio to a grid of expected losses for a model source at different distances from the centre of the beam, under the assumption that the SSW FTS beam can be well approximated by a Gaussian. In order to avoid dependency on the...

  8. The INAF contribution to the ASI Space Debris program: observational activities.

    Science.gov (United States)

    Pupillo, G.; Salerno, E.; Bartolini, M.; Di Martino, M.; Mattana, A.; Montebugnoli, S.; Portelli, C.; Pluchino, S.; Schillirò, F.; Konovalenko, A.; Nabatov, A.; Nechaeva, M.

    Space debris are man made objects orbiting around Earth that pose a serious hazard for both present and future human activities in space. Since 2007 the Istituto Nazionale di Astrofisica (INAF) carried out a number of radar campaigns in the framework of the ASI ``Space Debris'' program. The observations were performed by using bi- and multi-static radars, composed of the INAF 32-m Italian radiotelescopes located at Medicina and Noto (used as receivers) and the 70-m parabolic antenna at Evpatoria (Ukraine) used as transmitter. The 32 m Ventspils antenna in Latvia also participated in the last campaign at the end of June 2010. Several kinds of objects in various orbital regions (radar calibrators, rocket upper stages, debris of different sizes) were observed and successfully detected. Some unknown objects were also discovered in LEO during the beam-park sessions. In this paper we describe some results of the INAF-ASI space debris research activity.

  9. NASA's Earth Observations Commercialization Applications Program: A model for government promotion of commercial space opportunities

    Science.gov (United States)

    Macauley, Molly K.

    1995-01-01

    The role of government in promoting space commerce is a topic of discussion in every spacefaring nation. This article describes a new approach to government intervention which, based on its five-year track record, appears to have met with success. The approach, developed in NASA's Earth Observations Commercialization Application Program (EOCAP), offer several lessons for effective government sponsorship of commercial space development in general and of commercial remote sensing in particular.

  10. Tracking with particle filter for high-dimensional observation and state spaces

    CERN Document Server

    Dubuisson, Séverine

    2015-01-01

    This title concerns the use of a particle filter framework to track objects defined in high-dimensional state-spaces using high-dimensional observation spaces.  Current tracking applications require us to consider complex models for objects (articulated objects, multiple objects, multiple fragments, etc.) as well as multiple kinds of information (multiple cameras, multiple modalities, etc.). This book presents some recent research that considers the main bottleneck of particle filtering frameworks (high dimensional state spaces) for tracking in such difficult conditions.

  11. Spacetime and observer space symmetries in the language of Cartan geometry

    Science.gov (United States)

    Hohmann, Manuel

    2016-08-01

    We introduce a definition of symmetry generating vector fields on manifolds which are equipped with a first-order reductive Cartan geometry. We apply this definition to a number of physically motivated examples and show that our newly introduced notion of symmetry agrees with the usual notions of symmetry of affine, Riemann-Cartan, Riemannian, and Weizenböck geometries, which are conventionally used as spacetime models. Further, we discuss the case of Cartan geometries which can be used to model observer space instead of spacetime. We show which vector fields on an observer space can be interpreted as symmetry generators of an underlying spacetime manifold, and may hence be called "spatio-temporal." We finally apply this construction to Finsler spacetimes and show that symmetry generating vector fields on a Finsler spacetime are indeed in a one-to-one correspondence with spatio-temporal vector fields on its observer space.

  12. Impact of curvature divergences on physical observers in a wormhole space-time with horizons

    CERN Document Server

    Olmo, Gonzalo J; Sanchez-Puente, A

    2016-01-01

    The impact of curvature divergences on physical observers in a black hole space-time which, nonetheless, is geodesically complete is investigated. This space-time is an exact solution of certain extensions of General Relativity coupled to Maxwell's electrodynamics and, roughly speaking, consists on two Reissner-Nordstr\\"{o}m (or Schwarzschild or Minkowski) geometries connected by a spherical wormhole near the center. We find that, despite the existence of infinite tidal forces, causal contact is never lost among the elements making up the observer. This suggests that curvature divergences may not be as pathological as traditionally thought.

  13. Clarification on Polarity of Bipolar Electric Field Solitary Structures in Space Plasmas with Satellite Observation

    Institute of Scientific and Technical Information of China (English)

    M. N. S.Qureshi; SHI Jian-Kui; LIU Zhen-Xing; Klaus Torkar

    2011-01-01

    The bipolar electric field solitary (EFS) structures observed frequently in space plasmas by satellites have two different polarities, first positive electric field peak then negative (i.e., positive/negative) and first negative then positive peak (i.e., negative/positive). We provide the physical explanation on the polarity of observed bipolar EFS structures with an electrostatic ion fluid model. The results show that ii initial electric field E0 > 0, the polarity of the bipolar EFS structure will be positive/negative; and if E0 < 0, the polarity of the bipolar EFS structure will be negative/positive. However, for a fixed polarity of the EFS, either positive/negative or negative/positive, if the satellite is located at the positive side of the EFS, the observed polarity should be positive/negative, if the satellite is located at the negative side of the EFS, the observed polarity should be negative/positive. Therefore, we provide a method to clarify the natural polarity of the EFS with observed polarity by satellites. Our results are significant to understand the physical process in space plasma with the satellite observation.%@@ The bipolar electric field solitary (EFS) structures observed frequently in space plasmas by satellites have two different polarities, first positive electric Held peak then negative (i.e., positive/negative) and first negative then positive peak (i.e., negative/positive).We provide the physical explanation on the polarity of observed bipolar EFS structures with an electrostatic ion fluid model.

  14. Preliminary Results from Reflectance Spectroscopy Observations of Space Debris in GEO

    Science.gov (United States)

    Vananti, A.; Schidknecht, T.; Krag, H.; Erd, C.

    2009-03-01

    The space debris environment in the Geostationary Earth Orbit (GEO) region is mostly investigated using optical telescopes. The detection of the objects and the determination of their orbits are based on optical observations. However, for a better characterization of the environment it would be necessary to know the shape and the material of the objects. The area-to-mass ratio can be estimated from orbit determinations. In some rare case additional information can be derived from photometric measurements. A possible technique to investigate the material type of the debris is the reflectance spectroscopy. This paper discusses preliminary results obtained from spectrometric observations of orbital space debris. The observations were acquired at the 1-meter ESA Space Debris Telescope (ESASDT) on Tenerife with a low-resolution spectrograph in the wavelength range of 450-960 nm. The observed objects are space debris in GEO orbits with brightness as small as magnitude 16. The spectra show shape variations expected to be caused by the different physical properties of the objects. The determination of the material and of the type of object is still in a preliminary phase. Limitations of the acquisition process of the spectra and the subsequent analysis are discussed. Future steps planned for a better characterization of the debris from the observed data are briefly outlined.

  15. Ground-based Observations of the Solar Sources of Space Weather (Invited Review)

    CERN Document Server

    Veronig, Astrid M

    2016-01-01

    Monitoring of the Sun and its activity is a task of growing importance in the frame of space weather research and awareness. Major space weather disturbances at Earth have their origin in energetic outbursts from the Sun: solar flares, coronal mass ejections and associated solar energetic particles. In this review we discuss the importance and complementarity of ground-based and space-based observations for space weather studies. The main focus is drawn on ground-based observations in the visible range of the spectrum, in particular in the diagnostically manifold H$\\alpha$ spectral line, which enables us to detect and study solar flares, filaments, filament eruptions, and Moreton waves. Existing H$\\alpha$ networks such as the GONG and the Global High-Resolution H$\\alpha$ Network are discussed. As an example of solar observations from space weather research to operations, we present the system of real-time detection of H$\\alpha$ flares and filaments established at Kanzelh\\"ohe Observatory (KSO; Austria) in the...

  16. On observation distributions for state space models of population survey data.

    Science.gov (United States)

    Knape, Jonas; Jonzén, Niclas; Sköld, Martin

    2011-11-01

    1. State space models are starting to replace more simple time series models in analyses of temporal dynamics of populations that are not perfectly censused. By simultaneously modelling both the dynamics and the observations, consistent estimates of population dynamical parameters may be obtained. For many data sets, the distribution of observation errors is unknown and error models typically chosen in an ad-hoc manner. 2. To investigate the influence of the choice of observation error on inferences, we analyse the dynamics of a replicated time series of red kangaroo surveys using a state space model with linear state dynamics. Surveys were performed through aerial counts and Poisson, overdispersed Poisson, normal and log-normal distributions may all be adequate for modelling observation errors for the data. We fit each of these to the data and compare them using AIC. 3. The state space models were fitted with maximum likelihood methods using a recent importance sampling technique that relies on the Kalman filter. The method relaxes the assumption of Gaussian observation errors required by the basic Kalman filter. Matlab code for fitting linear state space models with Poisson observations is provided. 4. The ability of AIC to identify the correct observation model was investigated in a small simulation study. For the parameter values used in the study, without replicated observations, the correct observation distribution could sometimes be identified but model selection was prone to misclassification. On the other hand, when observations were replicated, the correct distribution could typically be identified. 5. Our results illustrate that inferences may differ markedly depending on the observation distributions used, suggesting that choosing an adequate observation model can be critical. Model selection and simulations show that for the models and parameter values in this study, a suitable observation model can typically be identified if observations are

  17. Monitoring of Landslides using Repeated Kinematics GPS Observables in Sevketiye Town, Biga Peninsula, Çanakkale, NW Turkey

    Science.gov (United States)

    Cuneyt Erenoglu, Ramazan; Akcay, Ozgun; Karaca, Zeki; Erenoglu, Oya; Sengul Uluocak, Ebru; Yucel, Mehmet Ali

    2014-05-01

    Landslide is one of the most important natural events, and is also a result of earth's crust movements. Landslides generally result in the outward and downward movement of slope-forming materials consisting soil, rock, artificial fill and etc. Moreover, possible earthquakes are one of the main reasons of triggering landslides in active areas seismically. There have been many studies based on the Global Positioning System (GPS) observables to compute the three dimensional positioning of established sites, and to model landslides precisely. We can monitor landslide with GPS using continuous data collection or the type of campaign surveying. While continuous data collection provide a millimetre-level of accuracy, the accuracy decreases with the shorter sessions, e.g. campaign surveying, due to possible sources of error. The area, located west of the Çanakkale, has been studied to identify the landslide susceptibility and geology. Çanakkale, NW Turkey, is located on the territory of the Biga Peninsula and the Gallipoli Peninsula. The section of remaining at the west of the line from the Gulf of Edremit to the Gulf of Erdek is called Biga Peninsula, and it covers an area of approximately 10 thousand km². In the Biga Peninsula, the main morphological units are at the western, northern and southern of coastal plains, and on their behind the hills, plateaus and mountainous areas of the inland. But at the middle areas, it is often possible to find the tectonic depressions sandwiched between the masses plateau and mountainous. In general, moving down the slope of a rock, soil or debris can be defined as landslides that are ranks second in terms of caused losses after earthquakes in Turkey. Landslides, harm to urbanization as well as loss of lives and economic losses. Moreover they adversely affects to agricultural, forest areas and the quality of the rivers. For example, the gas pipeline connecting Turkey and Greece, which will provide gas to the Southern Europe passes

  18. Observations of Interstellar Pickup Ions and their Suprathermal Tails in Interplanetary Space and in the Heliosheath

    Science.gov (United States)

    Gloeckler, George; Fisk, Len

    2014-10-01

    Since the invention of space-borne time-of-flight mass spectrometers in the late 1990s, distribution functions of singly charged interstellar pickup ions, produced primarily by charge exchange with the solar wind and by photoionization of the interstellar neutral gas, have been observed from 1 to ~5 AU in interplanetary space. Here we summarize observed characteristics of pickup ion spectra (primarily of H+ and He+) as well as of the pickup ion tails that are readily produced in Local Acceleration Regions in space, both at 1 AU and in the heliosheath, and briefly discuss the most likely mechanisms for producing interstellar pickup ions as well as their tails that in the heliosheath extend to high (~10 MeV/nuc) energies.

  19. Lightning Observations from the International Space Station (ISS) for Science Research and Operational Applications

    Science.gov (United States)

    Blakeslee, R. J.; Christian, H. J.; Mach, D. M.; Buechler, D. E.; Koshak, W. J.; Walker, T. D.; Bateman, M.; Stewart, M. F.; O'Brien, S.; Wilson, T.; hide

    2015-01-01

    There exist several core science applications of LIS lightning observations, that range from weather and climate to atmospheric chemistry and lightning physics due to strong quantitative connections that can be made between lightning and other geophysical processes of interest. The space-base vantage point, such as provided by ISS LIS, still remains an ideal location to obtain total lightning observations on a global basis.

  20. Choosing the observational likelihood in state-space stock assessment models

    DEFF Research Database (Denmark)

    Albertsen, Christoffer Moesgaard; Nielsen, Anders; Thygesen, Uffe Høgsbro

    By implementing different observational likelihoods in a state-space age-based stock assessment model, we are able to compare the goodness-of-fit and effects on estimated fishing mortallity for different model choices. Model fit is improved by estimating suitable correlations between agegroups. We...

  1. Observing at-surface irradiance and albedo from space: the Tibet experiment

    NARCIS (Netherlands)

    Roupioz, L.

    2015-01-01

    Monitoring the solar radiation budget on a daily basis is a prerequisite to study land surface processes, especially in climatology and hydrology, and in derived applications like drought early warning. Current space-born radiometers can provide daily observations to derive surface radiative fluxes

  2. Infrared Space Observatory with the observations of solid carbon dioxide in molecular clouds

    NARCIS (Netherlands)

    Gerakines, PA; Whittet, DCB; Ehrenfreund, P; Boogert, ACA; Tielens, AGGM; Schutte, WA; Chiar, JE; van Dishoeck, EF; Prusti, T; Helmich, FP; de Graauw, T

    1999-01-01

    Spectra of interstellar CO2 ice absorption features at a resolving power of lambda/Delta lambda approximate to 1500-2000 are presented for 14 lines of sight. The observations were made with the Short-Wavelength Spectrometer (SWS) of the Infrared Space Observatory (ISO). Spectral coverage includes th

  3. Earth Observation for Ecosystems Monitoring in Space and Time: A Special Issue in Remote Sensing

    OpenAIRE

    Duccio Rocchini

    2015-01-01

    This Editorial introduces the papers published in the special issue “Earth Observation for Ecosystems Monitoring in Space and Time” which includes the most important researchers in the field and the most challenging aspects of the application of remote sensing to study ecosystems.

  4. Quantifying Spatial and Seasonal Variability in Atmospheric Ammonia with In Situ and Space-Based Observations

    Science.gov (United States)

    Ammonia plays an important role in many biogeochemical processes, yet atmospheric mixing ratios arc not well known. Recently, methods have been developed for retrieving NH3 from space-based observations, but they have not been compared to in situ measurements. We have ...

  5. Weak lensing analysis of C1 1358+62 using Hubble Space Telescope observations

    NARCIS (Netherlands)

    Hoekstra, H; Franx, M; Kuijken, K; Squires, G

    1998-01-01

    We report on the detection of weak gravitational lensing of faint, distant background objects by Cl 1358+62, a rich cluster of galaxies at a redshift of z = 0.33. The observations consist of a large, multicolor mosaic of Hubble Space Telescope WFPC2 images. The number density of approximately 50 bac

  6. Multiple asteroid systems : Dimensions and thermal properties from Spitzer Space Telescope and ground-based observations

    NARCIS (Netherlands)

    Marchis, F.; Enriquez, J. E.; Emery, J. P.; Mueller, M.; Baek, M.; Pollock, J.; Assafin, M.; Vieira Martins, R.; Berthier, J.; Vachier, F.; Cruikshank, D. P.; Lim, L. F.; Reichart, D. E.; Ivarsen, K. M.; Haislip, J. B.; LaCluyze, A. P.

    2012-01-01

    We collected mid-IR spectra from 5.2 to 38 μm using the Spitzer Space Telescope Infrared Spectrograph of 28 asteroids representative of all established types of binary groups. Photometric lightcurves were also obtained for 14 of them during the Spitzer observations to provide the context of the

  7. Recent space shuttle observations of the South Atlantic anomaly and the radiation belt models

    Science.gov (United States)

    Konradi, A.; Badhwar, G. D.; Braby, L. A.

    1994-01-01

    Active ingredients consisting of Tissue Equivalent Proportional Counter (TEPC) and a Proton and Heavy Ion Detector (PHIDE) have been carried on a number of Space Shuttle flights. These instruments have allowed us to map out parts of the South Atlantic Particle Anomaly (SAA) and to compare some of it's features with predictions of the AP-8 energetic proton flux models. We have observed that consistent with the generally observed westward drift of the surface features of the terrestial magnetic field of the SAA has moved west by about 6.9 degrees longitude between the epoch year 1970 of the AP-8 solar maximum model and the Space Shuttle observations made twenty years later. However, calculations indicate that except for relatively brief periods following very large magnetic storms the SAA seems to occupy the same position in L-space as in 1970. After the great storm of 24 March 1991 reconfiguration of the inner radiation belt and/or proton injection into the inner belt, a second energetic proton belt was observed to form at approximately equal to 2. As confirmed by a subsequent flight observations, this belt was shown to persist at least for six months. Our measurements also indicate an upward shift in the L location of the primary belt from L = 1.4 to L = 1.5. In addition we confirm through direct real time observations the existence and the approximate magnitude of the East-West effect. If the need exists for improved and updated radiation belt models in the Space Station era, these observations point out the specific features that should be considered and incorporated when this task is undertaken.

  8. Observations of an extreme storm in interplanetary space caused by successive coronal mass ejections

    CERN Document Server

    Liu, Ying D; Kajdič, Primož; Kilpua, Emilia K J; Lugaz, Noé; Nitta, Nariaki V; Möstl, Christian; Lavraud, Benoit; Bale, Stuart D; Farrugia, Charles J; Galvin, Antoinette B

    2014-01-01

    Space weather refers to dynamic conditions on the Sun and in the space environment of the Earth, which are often driven by solar eruptions and their subsequent interplanetary disturbances. It has been unclear how an extreme space weather storm forms and how severe it can be. Here we report and investigate an extreme event with multi-point remote-sensing and in-situ observations. The formation of the extreme storm showed striking novel features. We suggest that the in-transit interaction between two closely launched coronal mass ejections resulted in the extreme enhancement of the ejecta magnetic field observed near 1 AU at STEREO A. The fast transit to STEREO A (in only 18.6 hours), or the unusually weak deceleration of the event, was caused by the preconditioning of the upstream solar wind by an earlier solar eruption. These results provide a new view crucial to solar physics and space weather as to how an extreme space weather event can arise from a combination of solar eruptions.

  9. Earth Observations from Space: The First 50 Years of Scientific Achievements

    Science.gov (United States)

    Minster, B.; Campbell, J. W.; Dozier, J.; Fleming, J. R.; Gille, J. C.; Hartmann, D. L.; Jezek, K.; Kidder, S.; Ramankutty, N.; Thompson, A.; Ustin, S. L.; Yoder, J.; Probst, L.; Mengelt, C.

    2007-12-01

    Observing the Earth from space over the last five decades has fundamentally transformed the way people view our home planet. The image of the "blue marble" is taken for granted now, but it was revolutionary when it was first taken in 1972 by the crew on Apollo 17. Since then, the capability to look at Earth from space has grown increasingly sophisticated and evolved from simple photographs to quantitative measurements of Earth properties such as temperature, atmospheric gases, and exact elevation of land and ocean. Consequently, every new method of imaging the Earth from space has resulted in scientific accomplishments that have enabled new discoveries, transformed the field, refined scientific understanding, opened new avenues of research, or provided important societal benefits by improving the predictability of Earth system processes. This National Research Council (NRC) study highlights selected scientific achievements made possible by the first 50 years of Earth satellite observations by space-faring nations. It follows on a recent report from the NRC entitled "Earth Science and Applications from Space: National Imperatives for the Next Decade and Beyond" (NRC 2007), also referred to as the "decadal study."

  10. Space-borne imaging observation of the terrestrial upper atmosphere by ISS-IMAP

    Science.gov (United States)

    Saito, Akinori; Otsuka, Yuichi; Yamamoto, Mamoru; Yamazaki, Atsushi; Yoshikawa, Ichiro; Sakanoi, Takeshi

    ISS-IMAP (Ionosphere, Mesosphere, upper Atmosphere, and Plasmasphere mapping) mission is a space-borne mission on the international space station (ISS) to elucidate the mesoscale structures in the ionosphere, the mesosphere, and the plasmasphere by imaging observations. ISS-IMAP measures the following three parameters: (1) distribution of the atmospheric gravity wave in the mesopause (87km), the ionospheric E-region (95km), and the ionospheric F-region (250km) (2) distribution of the ionized atmosphere in the ionospheric F-region (3) distribution of O+ and He+ ions in the ionosphere and plasmasphere. After the initial check outs, its observation was started in October 2012. ISS-IMAP consists of two imaging instruments on the Exposed Facility of Japanese Experiment Module of the International Space Station, EF of ISS-JEM. Visible-light and infrared spectrum imager (VISI) observes the Mesosphere and the Ionosphere. Extra ultraviolet imager (EUVI) observes the Ionosphere and the Plasmasphere. VISI observes the airglow of 730nm (OH, Alt. 85km), 762nm (O2, Alt. 95km), and 630nm (O, Alt. 250km) in the Nadir direction. The global distributions of the airglow structures whose scale size is 50-500km in the nightside of the Mesosphere and the Ionosphere have been obtained by the VISI observation. EUVI measures the resonant scattering of 30.4nm [He+] and 83.4nm [O+]. Its field- of-view is 15 degrees, and points the limb of the Earth to observe the vertical distribution of the ions. The continuous observation of ISS-IMAP started in October 2012. The coordinated observation between ISS-IMAP and the several ground-based instruments have been carried out to elucidate the coupling process between the lower atmosphere and the upper atmosphere by the wave structures in this scale.

  11. The James Webb Space Telescope and its Capability for for Exoplanet Observations

    Science.gov (United States)

    Clampin, Mark

    2012-01-01

    The James Webb Space Telescope (JWST) is a large aperture (6.5 .meter), cryogenic space telescope with a suite of near and mid-infrared instruments covering the wavelength range of 0.6 micron to 28 micron. JWST's primary science goal is to detect and characterize the first galaxies. It will also study the assembly of galaxies, star formation, and the formation of evolution of planetary systems. In this presentation we will discuss the status of the JWST project and review the expected scientific performance of the observatory for observations of exosolar planets by means of transit observations, and direct coronagraphic imaging. In particular we will discuss recent simulations of photometric and spectroscopic transit observations that demonstrate the capabilities of JWST to characterize superearth atmospheres in the light of recent Kepler and Corot discoveries

  12. The potential of space observations for pulsating pre-main sequence stars

    CERN Document Server

    Zwintz, Konstanze

    2016-01-01

    The first asteroseismic studies of pre-main sequence (pre-MS) pulsators have been conducted based on data from the space telescopes MOST and CoRoT with typical time bases of less than 40 days. With these data, a relation between the pulsational properties of pre-MS delta Scuti stars and their relative evolutionary phase on their way from the birthline to the zero-age main sequence was revealed. But it is evident from comparison with the more evolved pulsators in their main sequence or post-main sequence stages observed by the main Kepler mission, that many more questions could be addressed with significantly longer time bases and ultra-high precision. Here, I will discuss the observational status of pre-MS asteroseismology and the potential of future space observations for this research field.

  13. Simultaneous radar and spaced receiver VHF scintillation observations of ESF irregularities

    Directory of Open Access Journals (Sweden)

    D. Tiwari

    2006-07-01

    Full Text Available Simultaneous observations of equatorial spread F (ESF irregularities made on 10 nights during March-April 1998 and 1999, using an 18-MHz radar at Trivandrum (77° E, 8.5° N, dip 0.5° N and two spaced receivers recording scintillations on a 251-MHz signal at Tirunelveli (77.8° E, 8.7° N, dip 0.4° N, have been used to study the evolution of Equatorial Spread F (ESF irregularities. Case studies have been carried out on the day-to-day variability in ESF structure and dynamics, as observed by 18-MHz radar, and with spaced receiver measurements of average zonal drift Vo of the 251-MHz radio wave diffraction pattern on the ground, random velocity Vc, which is a measure of random changes in the characteristics of scintillation-producing irregularities, and maximum cross-correlation CI of the spaced receivers signals. Results show that in the initial phase of plasma bubble development, the greater the maximum height of ESF irregularities responsible for the radar backscatter, the greater the decorrelation is of the spaced receiver scintillation signals, indicating greater turbulence. The relationship of the maximum spectral width derived from the radar observations and CI also supports this result.

  14. Image processing improvement for optical observations of space debris with the TAROT telescopes

    Science.gov (United States)

    Thiebaut, C.; Theron, S.; Richard, P.; Blanchet, G.; Klotz, A.; Boër, M.

    2016-07-01

    CNES is involved in the Inter-Agency Space Debris Coordination Committee (IADC) and is observing space debris with two robotic ground based fully automated telescopes called TAROT and operated by the CNRS. An image processing algorithm devoted to debris detection in geostationary orbit is implemented in the standard pipeline. Nevertheless, this algorithm is unable to deal with debris tracking mode images, this mode being the preferred one for debris detectability. We present an algorithm improvement for this mode and give results in terms of false detection rate.

  15. Planet Sensitivity from Combined Ground- and Space-based Microlensing Observations

    CERN Document Server

    Zhu, Wei; Beichman, Charles; Novati, Sebastiano Calchi; Carey, Sean; Gaudi, B Scott; Henderson, Calen B; Penny, Matthew; Shvartzvald, Yossi; Yee, Jennifer C; Udalski, A; Poleski, R; Skowron, J; Kozlowski, S; Mroz, P; Pietrukowicz, P; Pietrzynski, G; Szymanski, M K; Soszynski, I; Ulaczyk, K; Wyrzykowski, L; Abe, F; Barry, R K; Bennett, D P; Bhattacharya, A; Fukunaga, D; Inayama, K; Koshimoto, N; Namba, S; Sumi, T; Suzuki, D; Tristram, P J; Wakiyama, Y; Yonehara, A; Maoz, D; Kaspi, S; Friedmann, M

    2015-01-01

    To move one step forward toward a Galactic distribution of planets, we present the first planet sensitivity analysis for microlensing events with simultaneous observations from space and the ground. We present this analysis for two such events, OGLE-2014-BLG-0939 and OGLE-2014-BLG-0124, which both show substantial planet sensitivity even though neither of them reached high magnification. This suggests that an ensemble of low to moderate magnification events can also yield significant planet sensitivity and therefore probability to detect planets. The implications of our results to the ongoing and future space-based microlensing experiments to measure the Galactic distribution of planets are discussed.

  16. Choosing the observational likelihood in state-space stock assessment models

    DEFF Research Database (Denmark)

    Albertsen, Christoffer Moesgaard; Nielsen, Anders; Thygesen, Uffe Høgsbro

    2016-01-01

    Data used in stock assessment models result from combinations of biological, ecological, fishery, and sampling processes. Since different types of errors propagate through these processes it can be difficult to identify a particular family of distributions for modelling errors on observations...... a priori. By implementing several observational likelihoods, modelling both numbers- and proportions-at-age, in an age based state-space stock assessment model, we compare the model fit for each choice of likelihood along with the implications for spawning stock biomass and average fishing mortality. We...... propose using AIC intervals based on fitting the full observational model for comparing different observational likelihoods. Using data from four stocks, we show that the model fit is improved by modelling the correlation of observations within years. However, the best choice of observational likelihood...

  17. Choosing the observational likelihood in state-space stock assessment models

    DEFF Research Database (Denmark)

    Albertsen, Christoffer Moesgaard; Nielsen, Anders; Thygesen, Uffe Høgsbro

    2017-01-01

    propose using AIC intervals based on fitting the full observational model for comparing different observational likelihoods. Using data from four stocks, we show that the model fit is improved by modelling the correlation of observations within years. However, the best choice of observational likelihood......Data used in stock assessment models result from combinations of biological, ecological, fishery, and sampling processes. Since different types of errors propagate through these processes it can be difficult to identify a particular family of distributions for modelling errors on observations...... a priori. By implementing several observational likelihoods, modelling both numbers- and proportions-at-age, in an age based state-space stock assessment model, we compare the model fit for each choice of likelihood along with the implications for spawning stock biomass and average fishing mortality. We...

  18. Space-time anisotropy: theoretical issues and the possibility of an observational test

    CERN Document Server

    , Sergey; Brinzei, Nicoleta

    2008-01-01

    The specific astrophysical data collected during the last decade causes the need for the modification of the expression for the Einstein-Hilbert action, and several attempts sufficing this need are known. The modification suggested in this paper stems from the possible anisotropy of space-time and this means the natural change of the simplest scalar in the least action principle. To provide the testable support to this idea, the optic-metrical parametric resonance is regarded - an experiment on the galactic scale based on the interaction between the electromagnetic radiation of cosmic masers and periodical gravitational waves emitted by close double systems or pulsars. Since the effect depends on the space-time metric, the possible anisotropy could reveal itself through observations. To give the corresponding theory predicting the corrections to the expected results of the experiment, the specific mathematical formalism of Finsler geometry was chosen. It was found that in case the anisotropy of the space-time...

  19. The magnetic field of the earth - Performance considerations for space-based observing systems

    Science.gov (United States)

    Webster, W. J., Jr.; Taylor, P. T.; Schnetzler, C. C.; Langel, R. A.

    1985-01-01

    Basic problems inherent in carrying out observations of the earth magnetic field from space are reviewed. It is shown that while useful observations of the core and crustal fields are possible at the peak of the solar cycle, the greatest useful data volume is obtained during solar minimum. During the last three solar cycles, the proportion of data with a planetary disturbance index of less than 2 at solar maximum was in the range 0.4-0.8 in comparison with solar minimum. It is found that current state of the art orbit determination techniques should eliminate orbit error as a problem in gravitational field measurements from space. The spatial resolution obtained for crustal field anomalies during the major satellite observation programs of the last 30 years are compared in a table. The relationship between observing altitude and the spatial resolution of magnetic field structures is discussed. Reference is made to data obtained using the Magsat, the Polar Orbiting Geophysical Observatory (POGO), and instruments on board the Space Shuttle.

  20. Ground-based Observations of the Solar Sources of Space Weather

    Science.gov (United States)

    Veronig, A. M.; Pötzi, W.

    2016-04-01

    Monitoring of the Sun and its activity is a task of growing importance in the frame of space weather research and awareness. Major space weather disturbances at Earth have their origin in energetic outbursts from the Sun: solar flares, coronal mass ejections and associated solar energetic particles. In this review we discuss the importance and complementarity of ground-based and space-based observations for space weather studies. The main focus is drawn on ground-based observations in the visible range of the spectrum, in particular in the diagnostically manifold Hα spectral line, which enables us to detect and study solar flares, filaments (prominences), filament (prominence) eruptions, and Moreton waves. Existing Hα networks such as the GONG and the Global High-Resolution Hα Network are discussed. As an example of solar observations from space weather research to operations, we present the system of real-time detection of Hα flares and filaments established at Kanzelhöhe Observatory (KSO; Austria) in the frame of the space weather segment of the ESA Space Situational Awareness programme (swe.ssa.esa.int). An evaluation of the system, which is continuously running since July 2013 is provided, covering an evaluation period of almost 2.5 years. During this period, KSO provided 3020 hours of real-time Hα observations at the ESA SWE portal. In total, 824 Hα flares were detected and classified by the real-time detection system, including 174 events of Hα importance class 1 and larger. For the total sample of events, 95 % of the automatically determined flare peak times lie within ±5 min of the values given in the official optical flares reports (by NOAA and KSO), and 76 % of the start times. The heliographic positions determined are better than ±5°. The probability of detection of flares of importance 1 or larger is 95 %, with a false alarm rate of 16 %. These numbers confirm the high potential of automatic flare detection and alerting from ground

  1. Halo Observations from the Ground and from Space: Further Checks on the Sprite Polarity Paradox

    Science.gov (United States)

    Williams, E.; Kuo, C.; Bor, J.; Satori, G.; Newsome, R. T.; Boldi, R. A.; Downes, E.; Saba, M. M.; Taylor, M. J.; Chen, A. B.; Lyons, W. A.

    2009-12-01

    In continuing efforts to verify the hypothesis that halos produced by negative polarity ground flashes provide a resolution to the ‘sprite polarity paradox’ and are caused by the fast initial charge transfer in the lightning return stroke, additional halo observations are considered from the ground and from space. The ground-based observations include standard frame-rate video cameras, a high-time resolution (40 microsec)) photometer (called PIPER), the National Lightning Detection Network (NLDN), and ELF charge moment observations from Nagycenk Observatory in Hungary. The space-based observations are measurements from the limb-viewing ISUAL satellite. The observations in support of the hypothesis are: (1) charge moments of the same magnitude required for sprites are evident for ‘negative’ halos, (2) negative halos outnumber positive halos in both ISUAL and PIPER observations, (3) short (working hypothesis are (1) ISUAL peak lightning brightnesses are no larger for negative than for positive halo-parent lightning flashes, (2) NLDN peak currents for brighter ‘positive’ halos are not notably larger than for dimmer ‘negative’ flashes, and (3) ELF measurements of charge moments for negative flashes tend to be greater than for positive flashes. An additional similarity between ground- and space-based observations is the tendency for halos to be produced by single-stroke negative flashes, a distinct departure from the statistics of stroke multiplicity for all negative flashes with large peak current. The reason for the polarity asymmetry in the parent lightning flash, at the origin of the sprite polarity asymmetry, remains an open question.

  2. Snowfall estimation from space-borne active and passive microwave observations

    Science.gov (United States)

    Grecu, M.

    2006-12-01

    In this study, an algorithm to estimate snowfall from passive and active microwave observations is formulated and analyzed using both simulated and real observations. A high resolution cloud resolving model (CRM) is used to simulate a snowfall event and space-borne radar and radiometer observations similar to those of the future Global Precipitation Mission (GPM) are synthesized from the CRM data. Then a combined radar- radiometer similar to that of Grecu et al. (2004) is applied to the synthetic data. It is found that in spite of dual-frequency radar and millimeter-wave radiometer observations, snow retrievals from GPM-like observations are subject to various uncertainties. Simple parameterizations are devised to minimize these uncertainties. The combined radar-radiometer, modified to account for differences between the instruments deployed in Wakasa Bay Experiment and the GPM instruments, is applied to real data from the Wakasa Bay Experiment. Results show the algorithm's feasibility.

  3. Space-based infrared scanning sensor LOS determination and calibration using star observation

    Science.gov (United States)

    Chen, Jun; Xu, Zhan; An, Wei; Deng, Xin-Pu; Yang, Jun-Gang

    2015-10-01

    This paper provides a novel methodology for removing sensor bias from a space based infrared (IR) system (SBIRS) through the use of stars detected in the background field of the sensor. Space based IR system uses the LOS (line of sight) of target for target location. LOS determination and calibration is the key precondition of accurate location and tracking of targets in Space based IR system and the LOS calibration of scanning sensor is one of the difficulties. The subsequent changes of sensor bias are not been taking into account in the conventional LOS determination and calibration process. Based on the analysis of the imaging process of scanning sensor, a theoretical model based on the estimation of bias angles using star observation is proposed. By establishing the process model of the bias angles and the observation model of stars, using an extended Kalman filter (EKF) to estimate the bias angles, and then calibrating the sensor LOS. Time domain simulations results indicate that the proposed method has a high precision and smooth performance for sensor LOS determination and calibration. The timeliness and precision of target tracking process in the space based infrared (IR) tracking system could be met with the proposed algorithm.

  4. Investigations into Generalization of Constraint-Based Scheduling Theories with Applications to Space Telescope Observation Scheduling

    Science.gov (United States)

    Muscettola, Nicola; Smith, Steven S.

    1996-01-01

    This final report summarizes research performed under NASA contract NCC 2-531 toward generalization of constraint-based scheduling theories and techniques for application to space telescope observation scheduling problems. Our work into theories and techniques for solution of this class of problems has led to the development of the Heuristic Scheduling Testbed System (HSTS), a software system for integrated planning and scheduling. Within HSTS, planning and scheduling are treated as two complementary aspects of the more general process of constructing a feasible set of behaviors of a target system. We have validated the HSTS approach by applying it to the generation of observation schedules for the Hubble Space Telescope. This report summarizes the HSTS framework and its application to the Hubble Space Telescope domain. First, the HSTS software architecture is described, indicating (1) how the structure and dynamics of a system is modeled in HSTS, (2) how schedules are represented at multiple levels of abstraction, and (3) the problem solving machinery that is provided. Next, the specific scheduler developed within this software architecture for detailed management of Hubble Space Telescope operations is presented. Finally, experimental performance results are given that confirm the utility and practicality of the approach.

  5. Space-Borne Observations of Intense Gamma-Ray Flashes (TGFs) Above Thunderstorms

    Science.gov (United States)

    Fishman, Gerald J.

    2010-01-01

    Intense millisecond flashes of MeV photons are being observed with space-borne detectors. These terrestrial gamma-ray flashes (TGFs) were discovered with the Burst and Transient Source Experiment (BATSE) aboard the Compton Gamma-Ray Observatory (CGRO) in the early 1990s. They are now being observed with several other instruments, including the Gamma-ray Burst Monitor (GBM) detectors on the Fermi Gamma-ray Space Telescope. Although Fermi-GBM was designed and optimized for the observation of cosmic gamma-ray bursts (GRBs), it has unprecedented capabilities for TGF observations. The TGFs usually have extremely hard continuous spectra, typical of highly-Comptonized bremsstrahlung radiation. These spectral are harder than those of GRBs, with photons extending to over 40 MeV. The most likely origin of these high-energy photons is bremsstrahlung radiation produced by a relativistic runaway avalanche electron beam. Such a beam is expected to be produced in an extended, intense electric field in or above thunderstorm regions. The altitude of origin and beaming characteristics of the radiation are quite uncertain. These TGFs may produce an appreciable radiation dose to passengers and crew in nearby aircraft. They have generated considerable observational and theoretical interest in recent years. Instruments are being designed specifically for TGF observations from new spacecraft as well as from airborne platforms.

  6. Observed Versus Modeled O 1356 Å and N2 LBH Emissions from the Earth's Space Environment

    Science.gov (United States)

    Hays, J.; Eastes, R.

    2011-12-01

    The O/N2 ratio, which can be derived from the O 1356 Å to N2 LBH (Lyman-Birge-Hopfield) emission ratio, is frequently used to quantify changes in the state of Earth's space environment. The brightness of these emissions also provides important constraints on the state of the space environment and its drivers, e.g., the solar irradiance. In this work, the observed O 1356 Å and LBH emissions from the GUVI (Global Ultraviolet Imager) on the TIMED (Thermosphere Ionosphere Mesosphere Energetics and Dynamics) satellite is compared to the calculated O 1356 Å and LBH emissions from the GLOW model. These comparisons allow us to examine the agreement between the observed and calculated emissions as well as their dependence on the emission cross sections. GUVI observations from 2010-2011 and coincident with solar irradiance observations from the Solar Dynamics Observatory (SDO), both at 30 second cadence, are used in the analysis. In addition, recent experimental excitation cross-section data are used to determine the N2 LBH brightness and its ratio to O 1356 Å. The observed 1356/LBH emission ratio (which is proportional to the O/N2 ratio) is approximately half that calculated, while the calculated emissions are both brighter than those observed. While uncertainties in both the calibrations of the instruments and the neutral densities of the atmosphere may contribute to the lack of agreement, the differences in the emission ratios indicate a need for better O 1356 Å emission cross sections.

  7. Influence of nuclear de-excitation on observables relevant for space exploration

    CERN Document Server

    Mancusi, Davide; Cugnon, Joseph; David, Jean-Christophe; Leray, Sylvie

    2010-01-01

    The composition of the space radiation environment inside spacecrafts is modified by the interaction with shielding material, with equipment and even with the astronauts' bodies. Accurate quantitative estimates of the effects of nuclear reactions are necessary, for example, for dose estimation and prediction of single-event-upset rates. To this end, it is necessary to construct predictive models for nuclear reactions, which usually consist of an intranuclear-cascade or quantum-molecular-dynamics stage, followed by a nuclear-de-excitation stage. While it is generally acknowledged that it is necessary to accurately simulate the first reaction stage, transport-code users often neglect or underestimate the importance of the choice of the de-excitation code. The purpose of this work is to prove that the de-excitation model is in fact a non-negligible source of uncertainty for the prediction of several observables of crucial importance for space applications. For some particular observables, the systematic uncertai...

  8. Space-Based Gravitational-Wave Observations as Tools for Testing General Relativity

    Science.gov (United States)

    Will, Clifford M.

    2004-01-01

    We continued a project, to analyse the ways in which detection and study of gravitational waves could provide quantitative tests of general relativity, with particular emphasis on waves that would be detectable by space-based observatories, such as LISA. This work had three foci: 1) Tests of scalar-tensor theories of gravity that, could be done by analyzing gravitational waves from neutron stars inspiralling into massive black holes, as detectable by LISA; 2) Study of alternative theories of gravity in which the graviton could be massive, and of how gravitational-wave observations by space-based detectors, solar-system tests, and cosmological observations could constrain such theories; and 3) Study of gravitational-radiation back reaction of particles orbiting black holes in general relativity, with emphasis on the effects of spin.

  9. Prospects for Observing Ultracompact Binaries with Space-Based Gravitational Wave Interferometers and Optical Telescopes

    Science.gov (United States)

    Littenberg, T. B.; Larson, S. L.; Nelemans, G.; Cornish, N. J.

    2012-01-01

    Space-based gravitational wave interferometers are sensitive to the galactic population of ultracompact binaries. An important subset of the ultracompact binary population are those stars that can be individually resolved by both gravitational wave interferometers and electromagnetic telescopes. The aim of this paper is to quantify the multimessenger potential of space-based interferometers with arm-lengths between 1 and 5 Gm. The Fisher information matrix is used to estimate the number of binaries from a model of the Milky Way which are localized on the sky by the gravitational wave detector to within 1 and 10 deg(exp 2) and bright enough to be detected by a magnitude-limited survey.We find, depending on the choice ofGW detector characteristics, limiting magnitude and observing strategy, that up to several hundred gravitational wave sources could be detected in electromagnetic follow-up observations.

  10. Observer Interface Analysis for Standardization to a Cloud Based Real-Time Space Situational Awareness (SSA)

    Science.gov (United States)

    Eilers, J.

    2013-09-01

    The interface analysis from an observer of space objects makes a standard necessary. This standardized dataset serves as input for a cloud based service, which aimed for a near real-time Space Situational Awareness (SSA) system. The system contains all advantages of a cloud based solution, like redundancy, scalability and an easy way to distribute information. For the standard based on the interface analysis of the observer, the information can be separated in three parts. One part is the information about the observer e.g. a ground station. The next part is the information about the sensors that are used by the observer. And the last part is the data from the detected object. Backbone of the SSA System is the cloud based service which includes the consistency check for the observed objects, a database for the objects, the algorithms and analysis as well as the visualization of the results. This paper also provides an approximation of the needed computational power, data storage and a financial approach to deliver this service to a broad community. In this context cloud means, neither the user nor the observer has to think about the infrastructure of the calculation environment. The decision if the IT-infrastructure will be built by a conglomerate of different nations or rented on the marked should be based on an efficiency analysis. Also combinations are possible like starting on a rented cloud and then go to a private cloud owned by the government. One of the advantages of a cloud solution is the scalability. There are about 3000 satellites in space, 900 of them are active, and in total there are about ~17.000 detected space objects orbiting earth. But for the computation it is not a N(active) to N problem it is more N(active) to N(apo peri) quantity of N(all). Instead of 15.3 million possible collisions to calculate a computation of only approx. 2.3 million possible collisions must be done. In general, this Space Situational Awareness System can be used as a

  11. First results of functioning of the Ukraine-China Telescope Network on Space Debris Observations

    Science.gov (United States)

    Shulga, A. V.; Kozyrev, E. S.; Sibiryakova, E. S.; Koshkin, N. I.; Blagodyr, Ya. T.; Epishev, V. P.; Blagodyr, Ya. T.; Epishev, V. P.; Mao, Yi; Li, Y.; Chen, Zh.; Tang, Zh.

    2010-05-01

    Substantial growth of space debris (SD) on the near-Earth orbits is caused by increasing launch number of the Earth artificial satellites (EAS). Leading space countries assign considerable efforts and contributions for creation, maintenance and development of space control systems (SCS). Effective work of SCS is achieved by usage of radio and optical means based both on the ground and space. Control system of space environment (CSSE) developed by National Space Agency is working in Ukraine. CSSE provides space tracking of up to 300 objects and supplies information about them to customers. Usage of optical telescopes belonging to Ukrainian research institutes and universities of Ministry of Education and Science (MES) is a prospective way to enlarge number of information sources about the SD at low orbits (less than 2500 km) for CSSE. The network of the MES telescopes has a perspective in international cooperation in particular with People's Republic of China. Ukraine and China are members of the Interagency Coordinating Committee on Space Debris; and in accordance with the resolution of the United Nations General Assembly #61/11, they are responsible for collection and distribution of data on SD. This project is directed towards creation of the first Ukrainian-Chinese network of optical telescopes for observations of the SD on the low orbits. The telescopes are equipped with the short focus objectives and sensitive TV CCD Watec cameras. A list of telescope features, such as an institution name, telescope abbreviation, focal length, f-number, field of view are given below: 1) RI NAO, FRT, 85 mm, 1.8, 4.2° x 3.2°; 2) RI AOONU, KT-50, 250 mm, 2.5, 1.5° x 1.1°; 3) AOLNU, TPL1M, 250 mm, 2.5, 1.5° x 1.1°; 4) LSRUNU, TPL1M, 85 mm, 1.5, 4.2° x3.2°; 5) ShAO, TV,85 mm, 1.8, 4.2° x 3.2°. An original method of TV observations of the low orbit objects with a static telescope was tested at all the telescopes. This method was developed and successfully used in RI NAO in

  12. The AFP-675 Far Ultraviolet Cameras experiment - Observations of the far-UV space environment

    Science.gov (United States)

    Carruthers, George R.; Morrill, Jeff S.; Dohne, Brian C.; Christensen, Susan A.

    1993-01-01

    The NRL's Far UV Cameras experiment flew aboard the Shuttle Orbiter on STS-39, in 1991: obtaining 105-200 nm measurements of the upper atmosphere, astronomical targets, and the Shuttle environment. Attention is presently given to observations of O2 density vs altitude in the nighttime atmosphere, the nocturnal ionosphere, Space Shuttle FUV glow, and photometry for both the stars and diffuse sources of 12 star fields at high and low galactic latitudes. The first FUV observations of the extended region of reflection nebulosity in Scorpius are included.

  13. Evidence for Type Ia Supernova Diversity from Ultraviolet Observations with the Hubble Space Telescope

    Science.gov (United States)

    2012-04-20

    reserved. Printed in the U.S.A. EVIDENCE FOR TYPE Ia SUPERNOVA DIVERSITY FROM ULTRAVIOLET OBSERVATIONS WITH THE HUBBLE SPACE TELESCOPE Xiaofeng Wang1,2,3...DATES COVERED 00-00-2012 to 00-00-2012 4. TITLE AND SUBTITLE Evidence for Type Ia Supernova Diversity from Ultraviolet Observations with the...spectroscopy and photometry of four Type Ia supernovae (SNe 2004dt, 2004ef, 2005M and 2005cf) obtained with the UV prism of the Advanced Camera for Surveys on

  14. On the Frontier: Some Observations of Surface Tension Phenomena from the International Space Station

    Science.gov (United States)

    Pettit, Don

    2016-11-01

    Frontiers are interesting places; they offer the possibility to make observations outside our normal range of experience. The International Space Station is such a frontier offering a local reduction in acceleration force by nearly a factor of a million thus allowing the observation of subtle phenomena that are typically masked on Earth. In this presentation we show a variety of unusually large length scale fluid interfacial phenomena dominated by electro-hydrodynamics, Marangoni convection, and non-Newtonian fluid mechanics. The experimental results presented are largely performed during weekends and other brief time-off periods allotted to the astronaut crew on the ISS.

  15. Observations of the Earth in polarized light from the US Space Shuttle

    Science.gov (United States)

    Roger, Jean-Claude; Santer, Richard; Herman, M.; Deuze, J.-L.; Whitehead, V. C.

    1991-01-01

    During the four American Space Shuttle missions of year 1985, the crewmembers took pictures of the Earth in polarized light. Different problems were encountered in the quantitative use of the data: induced polarization by the shuttle window, lack of calibration correction of the window polarization and enveloped in flight calibration methods. The analysis of the selected data first confirmed the previous observation over snow and sand. A low polarization on these surfaces was observed. On the other hand, the measurements show the potentiability of the polarization for agricultural inventory. Contamination of the atmosphere is well characterized.

  16. Gradual approach to realize lightning monitoring from space by means of VHF observations

    Science.gov (United States)

    Morimoto, T.; Kikuchi, H.; Ushio, T.; Kawasaki, Z.

    2010-12-01

    Lightning Research Group of Osaka University (LRG-OU) has been developing VHF Broadband Digital Interferometer (DITF) to image precise lightning channels and monitor lightning activity widely. DITF is an equipment to locate sources of impulsive VHF radiation based on the digital interferometric technique. In other words, DITF is a system to visualize lightning channel by VHF radio observations. The feature of DITF is its ultra-wide bandwidth (from 25 MHz to 100 MHz) and implicit redundancy for the direction-of-arrival (DOA) estimation. LRG-OU considers an application of the broadband DITF to the spaceborne measurement system because its fairly high resolutions and the compactness of the system are great advantages to be the space-borne one. To realize space-borne DITF, LRG-OU intends to have gradual approach for the development. As their first step, a VHF sensor on Maido-1 satellite is proposed to examine the feasibility of receiving VHF lightning impulses in space. Maido-1 is a small satellite manufactured by factory members of SOHLA (Space Oriented Higashi-Osaka Leading Associate). The SOHLA project represents a technology transfer program to expand the range of the space development community in Japan. The objective is to get SMEs (Small and Medium sized manufacturing Enterprises) involved in small space projects and new space technologies. Under the cooperative agreement, JAXA (Japan Aerospace Exploration Agency) intends to contribute to socio-economic development by returning its R&D results to the society, and SOHLA tries to revitalize the local economy through the commercialization of versatile small satellites. Maido-1 is in sun-synchronous polar orbit at an altitude of 660 kilometers. The VHF sensor comprises a single pair of an antenna, a band-pass filter with a pass band of 30-100MHz, an amplifier with a gain of 45dB and an analog-to-digital converter with a sampling rate of 200MS/s and 8-bit resolution to record broadband VHF signals. The 100 waveforms

  17. New color images of transient luminous events from dedicated observations on the International Space Station

    Science.gov (United States)

    Yair, Yoav; Rubanenko, Lior; Mezuman, Keren; Elhalel, Gal; Pariente, Meidad; Glickman-Pariente, Maya; Ziv, Baruch; Takahashi, Yukihiro; Inoue, Tomohiro

    2013-09-01

    During July-August 2011, Expedition 28/29 JAXA astronaut Satoshi Furukawa conducted TLE observations from the International Space Station in conjunction with the “Cosmic Shore” program produced by NHK. An EMCCD normal video-rate color TV camera was used to conduct directed observations from the Earth-pointing Cupola module. The target selection was based on the methodology developed for the MEIDEX sprite campaign on board the space shuttle Columbia in January 2003 (Ziv et al., 2004). The observation geometry was pre-determined and uploaded daily to the ISS with pointing options to limb, oblique or nadir, based on the predicted location of the storm with regards to the ISS. The pointing angle was rotated in real-time according to visual eyesight by the astronaut. We present results of 10 confirmed TLEs: 8 sprites, 1 sprite halo and 1 gigantic jet, out of displaced form the lightning light and (b) from the oblique view of a sprite halo, enable the calculation of dimensions and volumes occupied by these TLEs. Since time stamping on the ISS images was accurate within 1 s, matching with ELF and WWLLN data for the parent lightning location is limited. Nevertheless, the results prove that the ISS is an ideal platform for lightning and TLE observations, and careful operational procedures greatly enhance the value of observation time.

  18. Deployment Repeatability

    Science.gov (United States)

    2016-04-01

    controlled to great precision, but in a Cubesat , there may be no attitude determination at all. Such a Cubesat might treat sun angle and tumbling rates as...could be sensitive to small differences in motor controller timing. In these cases, the analyst might choose to model the entire deployment path, with...knowledge of the material damage model or motor controller timing precision. On the other hand, if many repeated and environmentally representative

  19. New Horizons: Long-Range Kuiper Belt Targets Observed by the Hubble Space Telescope

    Science.gov (United States)

    Benecchi, S. D.; Noll, K. S.; Weaver, H. A.; Spencer, J. R.; Stern, S. A.; Buie, M. W.; Parker, A. H.

    2014-01-01

    We report on Hubble Space Telescope (HST) observations of three Kuiper Belt Objects (KBOs), discovered in our dedicated ground-based search campaign, that are candidates for long-range observations from the New Horizons spacecraft: 2011 epochY31, 2011 HZ102, and 2013 LU35. Astrometry with HST enables both current and future critical accuracy improvements for orbit precision, required for possible New Horizons observations, beyond what can be obtained from the ground. Photometric colors of all three objects are red, typical of the Cold Classical dynamical population within which they reside; they are also the faintest KBOs to have had their colors measured. None are observed to be binary with HST above separations of approx. 0.02 arcsec (approx. 700 km at 44 AU) and delta m less than or equal to 0.5.

  20. Spatial scale invariance of aggregated dynamics - Application to crops cycle observed from space

    Science.gov (United States)

    Mangiarotti, S.; Le Jean, F.

    2014-12-01

    Observational data is always associated to specific time and space scales. When the observed area of study is homogeneous, the same dynamics can be expected at different observed scales. It is generally not the case. This is a common obstacle when comparing data or products of different resolution. This question is investigated here considering the cycles of rainfed crops observed from space in semi-arid regions. In such context, the rainfed crops are coupled to the climatic dynamics in a synchronized way, the observational signal can thus be seen as an aggregation of phase synchronized dynamics. In the first part of this work, a case study is implemented. Rössler chaotic systems are used for this purpose as elementary oscillators relating to homogeneous behavior. The 'observational' signal is obtained by aggregating additively the signals of several elementary chaotic systems. Analytically, it is found that the aggregated signal can be approximated by the Rössler system itself but with some parameterization changes. This result can be generalized to any system for which a canonical approximation is possible. Using the global modeling technique [1], this theoretical result is then illustrated practically, by showing that an approximation of the Rössler dynamics can be retrieved, without any a priori knowledge, from the aggregated signal. In the second part, the cycle of cereal crops observed from space in semi-arid conditions is investigated from real observational data (the GIMMS product of Normalized Difference Vegetation Index [2] is used for this purpose). A low-dimensional chaotic model could recently be obtained from a spatially aggregated signal which presents properties never observed from real data before: a toroidal and weakly dissipative dynamics [3]. These unusual properties are then retrieved at various places and scales. [1] Mangiarotti S., Coudret R., Drapeau L. & Jarlan L., 2012. Polynomial search and Global modelling: two algorithms for modeling

  1. Space charge and octupole driven resonance trapping observed at the CERN proton synchrotron

    CERN Document Server

    Franchetti, Giuliano; Giovannozzi, Massimo; Martini, Michel; Métral, Elias

    2003-01-01

    The combined effect of space charge and nonlinear resonance on beam loss and emittance was measured in a benchmarking experiment over a 1.2 s long flat bottom at 1.4 GeV kinetic energy in the presence of a single controllable octupole. By lowering the working point towards the resonance, a gradual transition from a loss-free core emittance blowup to a regime dominated by continuous loss was found. We compare the observation with 3D simulations based on a new analytical space charge model and obtain good agreement in the emittance blowup regime. Our explanation is in terms of the synchrotron oscillation, which causes a periodic tune modulation due to space charge, and leads to trapping and detrapping on the resonance islands. For working points very close to the resonance this induces a beam halo with large radius. The underlying dynamics is studied in detail, and it is claimed that the predicted halo in conjunction with a reduced dynamic aperture for the real machine lattice is the source of the loss observed...

  2. State of Art in space weather observational activities and data management in Europe

    Science.gov (United States)

    Stanislawska, Iwona

    One of the primary scientific and technical goals of space weather is to produce data in order to investigate the Sun impact on the Earth and its environment. Studies based on data mining philosophy yield increase the knowledge of space weather physical properties, modelling capabilities and gain applications of various procedures in space weather monitoring and forecasting. Exchanging tailored individually and/or jointly data between different entities, storing of the databases and making data accessible for the users is the most important task undertaken by investigators. National activities spread over Europe is currently consolidated pursuant to the terms of effectiveness and individual contributions embedded in joint integrated efforts. The role of COST 724 Action in animation of such a movement is essential. The paper focuses on the analysis of the European availability in the Internet near-real time and historical collections of the European ground based and satellite observations, operational indices and parameters. A detailed description of data delivered is included. The structure of the content is supplied according to the following selection: (1) observations, raw and/or corrected, updated data, (2) resolution, availability of real-time and historical data, (3) products, as the results of models and theory including (a) maps, forecasts and alerts, (b) resolution, availability of real-time and historical data, (4) platforms to deliver data. Characterization of the networking of stations, observatories and space related monitoring systems of data collections is integrated part of the paper. According to these provisions operational systems developed for these purposes is presented and analysed. It concerns measurements, observations and parameters from the theory and models referred to local, regional collections, European and worldwide networks. Techniques used by these organizations to generate the digital content are identified. As the reference pan

  3. Automated genotyping of dinucleotide repeat markers

    Energy Technology Data Exchange (ETDEWEB)

    Perlin, M.W.; Hoffman, E.P. [Carnegie Mellon Univ., Pittsburgh, PA (United States)]|[Univ. of Pittsburgh, PA (United States)

    1994-09-01

    The dinucleotide repeats (i.e., microsatellites) such as CA-repeats are a highly polymorphic, highly abundant class of PCR-amplifiable markers that have greatly streamlined genetic mapping experimentation. It is expected that over 30,000 such markers (including tri- and tetranucleotide repeats) will be characterized for routine use in the next few years. Since only size determination, and not sequencing, is required to determine alleles, in principle, dinucleotide repeat genotyping is easily performed on electrophoretic gels, and can be automated using DNA sequencers. Unfortunately, PCR stuttering with these markers generates not one band for each allele, but a pattern of bands. Since closely spaced alleles must be disambiguated by human scoring, this poses a key obstacle to full automation. We have developed methods that overcome this obstacle. Our model is that the observed data is generated by arithmetic superposition (i.e., convolution) of multiple allele patterns. By quantitatively measuring the size of each component band, and exploiting the unique stutter pattern associated with each marker, closely spaced alleles can be deconvolved; this unambiguously reconstructs the {open_quotes}true{close_quotes} allele bands, with stutter artifact removed. We used this approach in a system for automated diagnosis of (X-linked) Duchenne muscular dystrophy; four multiplexed CA-repeats within the dystrophin gene were assayed on a DNA sequencer. Our method accurately detected small variations in gel migration that shifted the allele size estimate. In 167 nonmutated alleles, 89% (149/167) showed no size variation, 9% (15/167) showed 1 bp variation, and 2% (3/167) showed 2 bp variation. We are currently developing a library of dinucleotide repeat patterns; together with our deconvolution methods, this library will enable fully automated genotyping of dinucleotide repeats from sizing data.

  4. Understanding the Longitudinal Variability of Equatorial Electrodynamics using integrated Ground- and Space-based Observations

    Science.gov (United States)

    Yizengaw, E.; Moldwin, M.; Zesta, E.

    2015-12-01

    The currently funded African Meridian B-Field Education and Research (AMBER) magnetometer array comprises more than thirteen magnetometers stationed globally in the vicinity of geomagnetic equator. One of the main objectives of AMBER network is to understand the longitudinal variability of equatorial electrodynamics as function of local time, magnetic activity, and season. While providing complete meridian observation in the region and filling the largest land-based gap in global magnetometer coverage, the AMBER array addresses two fundamental areas of space physics: first, the processes governing electrodynamics of the equatorial ionosphere as a function of latitude (or L-shell), local time, longitude, magnetic activity, and season, and second, ULF pulsation strength at low/mid-latitude regions and its connection with equatorial electrojet and density fluctuation. The global AMBER network can also be used to augment observations from space-based instruments, such us the triplet SWARM mission and the upcoming ICON missions. Thus, in coordination with space-based and other ground-based observations, the AMBER magnetometer network provides a great opportunity to understand the electrodynamics that governs equatorial ionosphere motions. In this paper we present the longitudinal variability of the equatorial electrodynamics using the combination of instruments onboard SWARM and C/NOFS satellites and ground-based AMBER network. Both ground- and pace-based observations show stronger dayside and evening sector equatorial electrodynamics in the American and Asian sectors compared to the African sector. On the other hand, the African sector is home to stronger and year-round ionospheric bubbles/irregularities compared to the American and Asian sectors. This raises the question if the evening sector equatorial electrodynamics (vertical drift), which is believed to be the main cause for the enhancement of Rayleigh-Taylor (RT) instability growth rate, is stronger in the

  5. Kaluza-Klein-Carmeli Metric from Quaternion-Clifford Space, Lorentz' Force, and Some Observables

    Directory of Open Access Journals (Sweden)

    Christianto V.

    2008-04-01

    Full Text Available It was known for quite long time that a quaternion space can be generalized to a Clifford space, and vice versa; but how to find its neat link with more convenient metric form in the General Relativity theory, has not been explored extensively. We begin with a representation of group with non-zero quaternions to derive closed FLRW metric [1], and from there obtains Carmeli metric, which can be extended further to become 5D and 6D metric (which we propose to call Kaluza-Klein-Carmeli metric. Thereafter we discuss some plausible implications of this metric, beyond describing a galaxy’s spiraling motion and redshift data as these have been done by Carmeli and Hartnett [4, 5, 6]. In subsequent section we explain Podkletnov’s rotating disc experiment. We also note possible implications to quantum gravity. Further observations are of course recommended in order to refute or verify this proposition.

  6. Coronagraphic demonstration experiment using aluminum mirrors for space infrared astronomical observations

    CERN Document Server

    Oseki, Shinji; Ishihara, Daisuke; Enya, Keigo; Haze, Kanae; Kotani, Takayuki; Kaneda, Hidehiro; Nishiyama, Miho; Abe, Lyu; Yamamuro, Tomoyasu

    2015-01-01

    For future space infrared astronomical coronagraphy, we perform experimental studies on the application of aluminum mirrors to a coronagraph. Cooled reflective optics is required for broad-band mid-infrared observations in space, while high-precision optics is required for coronagraphy. For the coronagraph instrument originally proposed for the next-generation infrared astronomical satellite project SPICA (SCI: SPICA Coronagraph Instrument), we fabricated and evaluated the optics consisting of high-precision aluminum off-axis mirrors with diamond-turned surfaces, and conducted a coronagraphic demonstration experiment using the optics with a coronagraph mask. We first measured the wave front errors (WFEs) of the aluminum mirrors with a He-Ne Fizeau interferometer to confirm that the power spectral densities of the WFEs satisfy the SCI requirements. Then we integrated the mirrors into an optical system and evaluated the overall performance of the system. As a result, we estimate the total WFE of the optics to b...

  7. Space Based Observations of Coronal Cavities in Conjunction with the Total Solar Eclipse of July 2010

    Science.gov (United States)

    Kucera, T. A.; Berger, T. E.; Druckmuller, M.; Dietzel, M.; Gibson, S. E.; Habbal, S. R.; Morgan, H.; Reeves, K. K.; Schmit, D. J.; Seaton, D. B.

    2010-01-01

    In conjunction with the total solar eclipse on July 11, 2010 we coordinated a campaign between ground and space based observations. Our specific goal was to augment the ground based measurement of corona) prominence cavity temperatures made using iron lines in the IR (Habbal et al. 2010 ApJ 719 1362) with measurements performed by space based instruments. Included in the campaign were Hinode/EIS, XRT and SOT, PROBA2/SWAP, SDO/AIA, SOHO/CDS and STEREO/SECCHI/EUVI, in addition to the ground based IR measurements. We plan to use a combination of line ratio and forward modeling techniques to investigate the density and temperature structure of the cavities at that time.

  8. Particle Filtering for Large Dimensional State Spaces with Multimodal Observation Likelihoods

    CERN Document Server

    Vaswani, Namrata

    2008-01-01

    We study efficient importance sampling techniques for particle filtering (PF) when either (a) the observation likelihood (OL) is frequently multimodal or heavy-tailed, or (b) the state space dimension is large or both. When the OL is multimodal, but the state transition pdf (STP) is narrow enough, the optimal importance density is usually unimodal. Under this assumption, many techniques have been proposed. But when the STP is broad, this assumption does not hold. We study how existing techniques can be generalized to situations where the optimal importance density is multimodal, but is unimodal conditioned on a part of the state vector. Sufficient conditions to test for the unimodality of this conditional posterior are derived. The number of particles, N, to accurately track using a PF increases with state space dimension, thus making any regular PF impractical for large dimensional tracking problems. We propose a solution that partially addresses this problem. An important class of large dimensional problems...

  9. Distributed Space Mission Design for Earth Observation Using Model-Based Performance Evaluation

    Science.gov (United States)

    Nag, Sreeja; LeMoigne-Stewart, Jacqueline; Cervantes, Ben; DeWeck, Oliver

    2015-01-01

    Distributed Space Missions (DSMs) are gaining momentum in their application to earth observation missions owing to their unique ability to increase observation sampling in multiple dimensions. DSM design is a complex problem with many design variables, multiple objectives determining performance and cost and emergent, often unexpected, behaviors. There are very few open-access tools available to explore the tradespace of variables, minimize cost and maximize performance for pre-defined science goals, and therefore select the most optimal design. This paper presents a software tool that can multiple DSM architectures based on pre-defined design variable ranges and size those architectures in terms of predefined science and cost metrics. The tool will help a user select Pareto optimal DSM designs based on design of experiments techniques. The tool will be applied to some earth observation examples to demonstrate its applicability in making some key decisions between different performance metrics and cost metrics early in the design lifecycle.

  10. Dynamic auroral storms on Saturn as observed by the Hubble Space Telescope.

    Science.gov (United States)

    Nichols, J D; Badman, S V; Baines, K H; Brown, R H; Bunce, E J; Clarke, J T; Cowley, S W H; Crary, F J; Dougherty, M K; Gérard, J-C; Grocott, A; Grodent, D; Kurth, W S; Melin, H; Mitchell, D G; Pryor, W R; Stallard, T S

    2014-05-28

    We present observations of significant dynamics within two UV auroral storms observed on Saturn using the Hubble Space Telescope in April/May 2013. Specifically, we discuss bursts of auroral emission observed at the poleward boundary of a solar wind-induced auroral storm, propagating at ∼330% rigid corotation from near ∼01 h LT toward ∼08 h LT. We suggest that these are indicative of ongoing, bursty reconnection of lobe flux in the magnetotail, providing strong evidence that Saturn's auroral storms are caused by large-scale flux closure. We also discuss the later evolution of a similar storm and show that the emission maps to the trailing region of an energetic neutral atom enhancement. We thus identify the auroral form with the upward field-aligned continuity currents flowing into the associated partial ring current.

  11. Observation of quantum particles on a large space-time scale

    Science.gov (United States)

    Landau, L. J.

    1994-10-01

    A quantum particle observed on a sufficiently large space-time scale can be described by means of classical particle trajectories. The joint distribution for large-scale multiple-time position and momentum measurements on a nonrelativistic quantum particle moving freely in R v is given by straight-line trajectories with probabilities determined by the initial momentum-space wavefunction. For large-scale toroidal and rectangular regions the trajectories are geodesics. In a uniform gravitational field the trajectories are parabolas. A quantum counting process on free particles is also considered and shown to converge in the large-space-time limit to a classical counting process for particles with straight-line trajectories. If the quantum particle interacts weakly with its environment, the classical particle trajectories may undergo random jumps. In the random potential model considered here, the quantum particle evolves according to a reversible unitary one-parameter group describing elastic scattering off static randomly distributed impurities (a quantum Lorentz gas). In the large-space-time weak-coupling limit a classical stochastic process is obtained with probability one and describes a classical particle moving with constant speed in straight lines between random jumps in direction. The process depends only on the ensemble value of the covariance of the random field and not on the sample field. The probability density in phase space associated with the classical stochastic process satisfies the linear Boltzmann equation for the classical Lorentz gas, which, in the limit h→0, goes over to the linear Landau equation. Our study of the quantum Lorentz gas is based on a perturbative expansion and, as in other studies of this system, the series can be controlled only for small values of the rescaled time and for Gaussian random fields. The discussion of classical particle trajectories for nonrelativistic particles on a macroscopic spacetime scale applies also to

  12. Evaluating tropospheric humidity observations from modern space-borne microwave instruments

    Science.gov (United States)

    Moradi, I.; Ferraro, R. R.

    2013-12-01

    Two main sources of tropospheric humidity data include radiosonde measurements as well as observations from space-borne microwave instruments operating at the frequencies close to the water vapor absorption line at 183 GHz. Radiosonde data are available for a long-period and have a high vertical resolution compared to the microwave satellite data. On the other hand, satellite data provide global coverage, but radiosonde stations are very sparse. Both space-based and radiosonde observations are prone to different errors. Radiosonde data are affected by several factors including sensor contamination, daytime radiation bias, sensor icing in mid-upper troposphere, and discontinuity in the data because of the difference between observations from different sonde sensors. Microwave satellite data are also prone to several errors including calibration drift, geolocation error, sensor degradation, and inter-satellite biases. We present the results of evaluating observations from microwave instruments aboard recently launched the Suomi National Polar-orbiting Partnership (NPP, ATMS instrument) and Megha-Tropiques (SAPHIR instrument) satellites. The study includes inter-comparison and inter-calibration of observations of similar channels from the two satellites, evaluation of the satellite data using high-quality radiosonde data from Atmospheric Radiation Measurement Program, as well as geolocation error correction. The results of this study are valuable for generating climate data records from these instruments as well as for extending current climate data records from similar instruments such as AMSU-B and MHS to the ATMS and SAPHIR instruments. Brightness temperatures from different SAPHIR channels Inter-comparing SAPHIR and ATMS data (observations and simulations)

  13. Space Weather Observations by GNSS Radio Occultation: From FORMOSAT-3/COSMIC to FORMOSAT-7/COSMIC-2

    Science.gov (United States)

    Yue, Xinan; Schreiner, William S; Pedatella, Nicholas; Anthes, Richard A; Mannucci, Anthony J; Straus, Paul R; Liu, Jann-Yenq

    2014-01-01

    The joint Taiwan-United States FORMOSAT-3/COSMIC (Constellation Observing System for Meteorology, Ionosphere, and Climate) mission, hereafter called COSMIC, is the first satellite constellation dedicated to remotely sense Earth's atmosphere and ionosphere using a technique called Global Positioning System (GPS) radio occultation (RO). The occultations yield abundant information about neutral atmospheric temperature and moisture as well as space weather estimates of slant total electron content, electron density profiles, and an amplitude scintillation index, S4. With the success of COSMIC, the United States and Taiwan are moving forward with a follow-on RO mission named FORMOSAT-7/COSMIC-2 (COSMIC-2), which will ultimately place 12 satellites in orbit with two launches in 2016 and 2019. COSMIC-2 satellites will carry an advanced Global Navigation Satellite System (GNSS) RO receiver that will track both GPS and Russian Global Navigation Satellite System signals, with capability for eventually tracking other GNSS signals from the Chinese BeiDou and European Galileo system, as well as secondary space weather payloads to measure low-latitude plasma drifts and scintillation at multiple frequencies. COSMIC-2 will provide 4–6 times (10–15X in the low latitudes) the number of atmospheric and ionospheric observations that were tracked with COSMIC and will also improve the quality of the observations. In this article we focus on COSMIC/COSMIC-2 measurements of key ionospheric parameters. PMID:26213514

  14. Status of Telescope Fabra ROA at Montsec: Optical Observations for Space Surveillance & Tracking

    CERN Document Server

    Fors, O; Nunez, J; Muinos, J L; Boloix, J; Baena, R; Morcillo, R; Merino, M

    2011-01-01

    The telescope Fabra ROA at Montsec (TFRM) is a 0.5m f/1 refurbished Baker-Nunn Camera (BNC) operated by a collaboration between the Fabra Observatory - Royal Academy of Arts and Sciences of Barcelona and the Spanish Navy Observatory (ROA), and installed at Montsec Astronomical Observatory (Spain). Among other capabilities, its CCD FoV (4.4{\\deg}x4.4{\\deg}), the telescope tracking at arbitrary RA and DEC rates, and the CCD shutter commanding at will during the exposure are specially remarkable for Space Surveillance and Tracking (SST) observational programs. On Feb 2011, the TFRM participated, in the CO-VI third run satellite tracking campaign of the ESA SST/Space Surveillance Awareness Preparatory Program (SST/SSA-PP). During this multi-asset 7-day campaign the TFRM conducted systematic observations of artificial satellites which yielded to the determination of 1137 accurate position measurements. Since Feb 2011, the TFRM is observing in remote and fully unattended robotic modes under commissioning status. A ...

  15. Extreme wave analysis in the space-time domain: from observations to applications

    Science.gov (United States)

    Barbariol, Francesco; Alves, Jose-Henrique; Benetazzo, Alvise; Bergamasco, Filippo; Carniel, Sandro; Chao, Yung Y.; Chawla, Arun; Ricchi, Antonio; Sclavo, Mauro

    2016-04-01

    The occurrence of extreme waves is one of the most dangerous marine hazards and one of the most challenging sea surface phenomena to be understood. Many severe accidents and casualties at sea are ascribed to the occurrence of abnormally high waves. Despite significant efforts to investigate their occurrence, up to now research has not yet provided exhaustive experimental and theoretical frameworks able to fully explain the development of extremely large waves (i.e. waves that are outlier from standard wave statistics). Recently, relying on the stereo-photogrammetric instrumentation known as "Wave Acquisition Stereo System", it was observed that the number of waves that can be labeled as "freak" increases significantly if the domain of observation is extended from the time (i.e. the classical point time series), to the space-time (i.e. a time sequence of sea surface snapshots covering an area). The empirical statistics of such extremely high waves gathered during a sea state over an area, outlying standard linear and nonlinear extreme value models, have been found in fair agreement with a statistical model accounting for the probability of a maximum crest height occurring in a space-time domain of given size. This model, developed by Fedele (2012) and extended to second order nonlinear waves by Benetazzo et al (2015), relies upon the Euler Characteristics approach of Adler and Taylor (2007), and upon the knowledge of kinematic and geometric properties of the sea state that can be obtained from the directional spectrum of the sea surface. Therefore, new efforts have been put on applying this approach to provide an interpretation of the occurrence of extreme crest heights in sea states, observed via stereo photography. Results have allowed the development of applications in ocean engineering and weather forecasting. In the former, the statistical model of Fedele has been used to investigate the role of metocean forcings on the space-time extremes of sea states. To

  16. Predictability of GNSS signal observations in support of Space Situational Awareness using passive radar

    Science.gov (United States)

    Mahmud, M. S.; Lambert, A.; Benson, C.

    2015-07-01

    GNSS signals have been proposed as emitters of opportunity to enhance Space Situational Awareness (SSA) by tracking small items of space debris using bistatic radar. Although the scattered GNSS signal levels from small items of space debris are incredibly low, the dynamic disturbances of the observed object are very small, and the phase of the scattered signals is well behaved. It is therefore plausible that coherent integration periods on the order of many minutes could be achieved. However, even with long integration periods, very large receiver arrays with extensive, but probably viable, processing are required to recover the scattered signal. Such large arrays will be expensive, and smaller more affordable arrays will collect insufficient signal power to detect the small objects (relative to wavelength) that are necessary to maintain the necessary phase coherency. The investments necessary to build a large receiver array are unlikely without substantial risk reduction. Pini and Akos have previously reported on use of very large radio telescopes to analyse the short-term modulation performance of GNSS satellite signals. In this work we report on tracking of GPS satellites with a radio-astronomy VLBI antenna system to assess the stability of the observed GPS signal over a time period indicative of that proposed for passive radar. We also confirm some of the processing techniques that may be used in both demonstrations and the final system. We conclude from the limited data set that the signal stability when observed by a high-gain tracking antenna and compared against a high quality, low phase-noise clock is excellent, as expected. We conclude by framing further works to reduce risk for a passive radar SSA capability using GNSS signals. http://www.ignss.org/Conferences/PastConferencePapers/2015ConferencePastPapers/2015PeerReviewedPapers/tabid/147/Default.aspx

  17. Space geodetic observations of nazca-south america convergence across the central andes

    Science.gov (United States)

    Norabuena; Leffler-Griffin; Mao; Dixon; Stein; Sacks; Ocola; Ellis

    1998-01-16

    Space geodetic data recorded rates and directions of motion across the convergent boundary zone between the oceanic Nazca and continental South American plates in Peru and Bolivia. Roughly half of the overall convergence, about 30 to 40 millimeters per year, accumulated on the locked plate interface and can be released in future earthquakes. About 10 to 15 millimeters per year of crustal shortening occurred inland at the sub-Andean foreland fold and thrust belt, indicating that the Andes are continuing to build. Little (5 to 10 millimeters per year) along-trench motion of coastal forearc slivers was observed, despite the oblique convergence.

  18. Markov chain Monte Carlo methods for state-space models with point process observations.

    Science.gov (United States)

    Yuan, Ke; Girolami, Mark; Niranjan, Mahesan

    2012-06-01

    This letter considers how a number of modern Markov chain Monte Carlo (MCMC) methods can be applied for parameter estimation and inference in state-space models with point process observations. We quantified the efficiencies of these MCMC methods on synthetic data, and our results suggest that the Reimannian manifold Hamiltonian Monte Carlo method offers the best performance. We further compared such a method with a previously tested variational Bayes method on two experimental data sets. Results indicate similar performance on the large data sets and superior performance on small ones. The work offers an extensive suite of MCMC algorithms evaluated on an important class of models for physiological signal analysis.

  19. The relativistic invariant Lie algebra for the kinematical observables in quantum space-time

    CERN Document Server

    Khrushchov, V V

    2003-01-01

    The deformation of the canonical algebra for the kinematical observables in Minkowski space has been considered under the condition of Lorentz invariance. A new relativistic invariant algebra depends on the fundamental constants $M$, $L$ and $H$ with the dimensionality of mass, length and action, respectively. In some limit cases the algebra obtained goes over into the well-known Snyder or Yang algebras. In general case the algebra represents a class of Lie algebras, which are either simple algebras, or semidirect sums of simple algebras integrable ones. T and C noninvariance for certain algebras of this class have been elucidated.

  20. The Planning of Lander Science Observations after ROSETTA Deep Space Hibernation

    Science.gov (United States)

    Barthelemy, Maud; Ulamec, Stephan; Gaudon, Philippe; Biele, Jens; Pätz, Brigitte; Ashman, Mike

    2014-05-01

    Scientists. It is then validated with the Ground Reference Model (GRM). The telecommands are then sent to Rosetta Ground Segment for uplink and execution. The Rosetta mission is very challenging particularly with respect to the landing. Once landed, the Lander will have to repeatedly charge its battery. Planning observations in advance without knowing the landing site nor the battery charging status at a given time is also a great challenge. Finally, further complexity is introduced with the need to plan and execute combined observations between complimentary Lander and Orbiter instruments.

  1. Precision simulation of ground-based lensing data using observations from space

    CERN Document Server

    Mandelbaum, Rachel; Leauthaud, Alexie; Massey, Richard J; Rhodes, Jason

    2011-01-01

    Current and upcoming wide-field, ground-based, broad-band imaging surveys promise to address a wide range of outstanding problems in galaxy formation and cosmology. Several such uses of ground-based data, especially weak gravitational lensing, require highly precise measurements of galaxy image statistics with careful correction for the effects of the point-spread function (PSF). In this paper, we introduce the SHERA (SHEar Reconvolution Analysis) software to simulate ground-based imaging data with realistic galaxy morphologies and observing conditions, starting from space-based data (from COSMOS, the Cosmological Evolution Survey) and accounting for the effects of the space-based PSF. This code simulates ground-based data, optionally with a weak lensing shear applied, in a model-independent way using a general Fourier space formalism. The utility of this pipeline is that it allows for a precise, realistic assessment of systematic errors due to the method of data processing, for example in extracting weak len...

  2. The performance of field scientists undertaking observations of early life fossils while in simulated space suit

    Science.gov (United States)

    Willson, D.; Rask, J. C.; George, S. C.; de Leon, P.; Bonaccorsi, R.; Blank, J.; Slocombe, J.; Silburn, K.; Steele, H.; Gargarno, M.; McKay, C. P.

    2014-01-01

    We conducted simulated Apollo Extravehicular Activity's (EVA) at the 3.45 Ga Australian 'Pilbara Dawn of life' (Western Australia) trail with field and non-field scientists using the University of North Dakota's NDX-1 pressurizable space suit to overview the effectiveness of scientist astronauts employing their field observation skills while looking for stromatolite fossil evidence. Off-world scientist astronauts will be faced with space suit limitations in vision, human sense perception, mobility, dexterity, the space suit fit, time limitations, and the psychological fear of death from accidents, causing physical fatigue reducing field science performance. Finding evidence of visible biosignatures for past life such as stromatolite fossils, on Mars, is a very significant discovery. Our preliminary overview trials showed that when in simulated EVAs, 25% stromatolite fossil evidence is missed with more incorrect identifications compared to ground truth surveys but providing quality characterization descriptions becomes less affected by simulated EVA limitations as the science importance of the features increases. Field scientists focused more on capturing high value characterization detail from the rock features whereas non-field scientists focused more on finding many features. We identified technologies and training to improve off-world field science performance. The data collected is also useful for NASA's "EVA performance and crew health" research program requirements but further work will be required to confirm the conclusions.

  3. Comparison of optical observational capabilities for the coming decades: ground versus space

    CERN Document Server

    Mountain, Matt; Soummer, Remi; Koekemoer, Anton; Ferguson, Harry; Postman, Marc; Gavel, Donald T; Guyon, Olivier; Simons, Douglas; Traub, Wesley A

    2009-01-01

    Ground-based adaptive optics (AO) in the infrared has made exceptional advances in approaching space-like image quality at higher collecting area. Optical-wavelength applications are now also growing in scope. We therefore provide here a comparison of the pros and cons of observational capabilities from the ground and from space at optical wavelengths. With an eye towards the future, we focus on the comparison of a ~30m ground-based telescope with an 8-16m space-based telescope. We review the current state-of-the-art in AO, and summarize the expected future improvements in image quality, field of view, contrast, and low-wavelength cut-off. We discuss the exciting advances in extreme AO for exoplanet studies and explore what the theoretical limitations in achievable contrast might be. Our analysis shows that extreme AO techniques face both fundamental and technological hurdles to reach the contrast of 1E-10 necessary to study an Earth-twin at 10 pc. Based on our assessment of the current state-of-the-art, the ...

  4. Observability and Estimation of Distributed Space Systems via Local Information-Exchange Networks

    Science.gov (United States)

    Fathpour, Nanaz; Hadaegh, Fred Y.; Mesbahi, Mehran; Rahmani, Amirreza

    2011-01-01

    Spacecraft formation flying involves the coordination of states among multiple spacecraft through relative sensing, inter-spacecraft communication, and control. Most existing formation-flying estimation algorithms can only be supported via highly centralized, all-to-all, static relative sensing. New algorithms are proposed that are scalable, modular, and robust to variations in the topology and link characteristics of the formation exchange network. These distributed algorithms rely on a local information exchange network, relaxing the assumptions on existing algorithms. Distributed space systems rely on a signal transmission network among multiple spacecraft for their operation. Control and coordination among multiple spacecraft in a formation is facilitated via a network of relative sensing and interspacecraft communications. Guidance, navigation, and control rely on the sensing network. This network becomes more complex the more spacecraft are added, or as mission requirements become more complex. The observability of a formation state was observed by a set of local observations from a particular node in the formation. Formation observability can be parameterized in terms of the matrices appearing in the formation dynamics and observation matrices. An agreement protocol was used as a mechanism for observing formation states from local measurements. An agreement protocol is essentially an unforced dynamic system whose trajectory is governed by the interconnection geometry and initial condition of each node, with a goal of reaching a common value of interest. The observability of the interconnected system depends on the geometry of the network, as well as the position of the observer relative to the topology. For the first time, critical GN&C (guidance, navigation, and control estimation) subsystems are synthesized by bringing the contribution of the spacecraft information-exchange network to the forefront of algorithmic analysis and design. The result is a

  5. NASA's Earth Observations of the Global Environment: Our Changing Planet and the View from Space

    Science.gov (United States)

    King, Michael D.

    2008-01-01

    Observations of the Earth from space over the past 30 years has enabled an increasingly detailed view of our Earth's atmosphere, land, oceans, and cryosphere, and its many alterations over time. With the advent of improvements in technology, together with increased understanding of the physical principles of remote sensing, it is now possible to routinely observe the global distribution of atmospheric constituents, including both cloud and aerosol optical properties, land surface reflectance, sea ice and glaciers, and numerous properties of the world's oceans. This talk will review the current status of recent NASA Earth observing missions, and summarize key findings. These missions include EOS missions such as Landsat 7, QuikScat, Terra, Jason-1, Aqua, ICESat, SORCE, and Aura, as well as Earth probe missions such as TRMM and SeaWiFS. Recent findings from Cloud- Sat and CALIPSO from the Earth System Science Pathfinder program will also be summarized, if time permits. Due to its wide utilization by the Earth science community, both in the US and abroad, special emphasis will be placed on the Moderate Resolution Imaging Spectroradiometer (MODIS), developed by NASA and launched onboard the Terra spacecraft in 1999 and the Aqua spacecraft in 2002. As the quintessential instrument of the Earth Observing System, it is widely used for studies of the oceans, land, and atmosphere, and its lengthening time series of Earth observations is finding utilization in many communities for both climate, weather, and applications use.

  6. Non-Blazhko RR Lyrae Stars Observed with the KEPLER Space Telescope

    CERN Document Server

    Nemec, J M; Benko, J M; Moskalik, P; Kolenberg, K; Szabo, R; Kurtz, D W; Bryson, S; Guggenberger, E; Chadid, M; Jeon, Y -B; Kunder, A; Layden, A C; Kinemuchi, K; Kiss, L L; Poretti, E; Christensen-Dalsgaard, J; Kjeldsen, H; Caldwell, D; Ripepi, V; Derekas, A; Nuspl, J; Mullally, F; Thompson, S E; Borucki, W J

    2011-01-01

    This paper summarizes the main results of our recent study of the non-Blazhko RR Lyrae stars observed with the Kepler space telescope. These stars offer the opportunity for studying the stability of the pulsations of RR Lyrae stars and for providing a reference against which the Blazhko RR Lyrae stars can be compared. Of particular interest is the stability of the low-dispersion (sigma < 1mmag) light curves constructed from ~18,000 long-cadence (30-min) and (for FN Lyr and AW Dra) the ~150,000 short-cadence (1-min) photometric data points. Fourier-based [Fe/H] values and other physical characteristics are also derived. When the observed periods are compared with periods computed with the Warsaw non-linear convective pulsation code better agreement is achieved assuming pulsational L and M values rather than the (higher) evolutionary L and M values.

  7. In Situ Observations of Ion Scale Current Sheets and Associated Electron Heating in Turbulent Space Plasmas

    Science.gov (United States)

    Chasapis, A.; Retino, A.; Sahraoui, F.; Greco, A.; Vaivads, A.; Khotyaintsev, Y. V.; Sundkvist, D. J.; Canu, P.

    2014-12-01

    We present a statistical study of ion-scale current sheets in turbulent space plasma. The study was performed using in situ measurements from the Earth's magnetosheath downstream of the quasi-parallel shock. Intermittent structures were identified using the Partial Variance of Increments method. We studied the distribution of the identified structures as a function of their magnetic shear angle, the PVI index and the electron heating. The properties of the observed current sheets were different for high (>3) and low (3) structures that accounted for ~20% of the total. Those current sheets have high magnetic shear (>90 degrees) and were observed mostly in close proximity to the bow shock with their numbers reducing towards the magnetopause. Enhancement of the estimated electron temperature within these current sheets suggest that they are important for local electron heating and energy dissipation.

  8. James Webb Space Telescope Observations of Stellar Occultations by Solar System Bodies and Rings

    Science.gov (United States)

    Santos-Sanz, P.; French, R. G.; Pinilla-Alonso, N.; Stansberry, J.; Lin, Z-Y.; Zhang, Z-W.; Vilenius, E.; Mueller, Th.; Ortiz, J. L.; Braga-Ribas, F.; hide

    2016-01-01

    In this paper, we investigate the opportunities provided by the James Webb Space Telescope (JWST) for significant scientific advances in the study of Solar System bodies and rings using stellar occultations. The strengths and weaknesses of the stellar occultation technique are evaluated in light of JWST's unique capabilities. We identify several possible JWST occultation events by minor bodies and rings and evaluate their potential scientific value. These predictions depend critically on accurate a priori knowledge of the orbit of JWST near the Sun–Earth Lagrange point 2 (L2). We also explore the possibility of serendipitous stellar occultations by very small minor bodies as a byproduct of other JWST observing programs. Finally, to optimize the potential scientific return of stellar occultation observations, we identify several characteristics of JWST's orbit and instrumentation that should be taken into account during JWST's development.

  9. THEMIS ground-space observations during the development of auroral spirals

    Directory of Open Access Journals (Sweden)

    A. Keiling

    2009-11-01

    Full Text Available A simultaneous observation of an auroral spiral and its generator region in the near-Earth plasma sheet is rather unlikely. Here we present such observations using the THEMIS spacecraft as well as the THEMIS ground network of all-sky imagers and magnetometers. Two consecutive auroral spirals separated by approximately 14 min occurred during a substorm on 19 February 2008. The spirals formed during the expansion phase and a subsequent intensification, and were among the brightest features in the aurora with diameters of 200–300 km. The duration for the formation and decay of each spiral was less than 60 s. Both spirals occurred shortly after the formation of two oppositely rotating plasma flow vortices in space, which were also accompanied by dipolarizations and ion injections, at ~11 RE geocentric distance. Observations and model calculations also give evidence for a magnetic-field-aligned current generation of approximately 0.1 MA via the flow vortices, connecting the generator region of the spirals with the ionosphere, during the formation of both spirals. In the ionosphere, a pair of equivalent ionospheric current (EIC vortices with opposite rotations (corresponding to upward and downward currents was present during both auroral spirals with enhanced EICs and ionospheric flows at the locations of the auroral spirals and along the auroral arcs. The combined ground and space observations suggest that each auroral spiral was powered by two oppositely rotating plasma flow vortices that caused a current enhancement in the substorm current wedge.

  10. On the non-equivalence of observables in phase-space reconstructions from recorded time series

    Science.gov (United States)

    Letellier, C.; Maquet, J.; LeSceller, L.; Gouesbet, G.; Aguirre, L. A.

    1998-10-01

    In practical problems of phase-space reconstruction, it is usually the case that the reconstruction is much easier using a particular recorded scalar variable. This seems to contradict the general belief that all variables of a dynamical system are equivalent in phase-space reconstruction problems. This paper will argue that, in many cases, the choice of a particular scalar time series from which to reconstruct the original dynamics could be critical. It is argued that different dynamical variables do not provide the same level of information (observability) of the underlying dynamics and, as a consequence, the quality of a global reconstruction critically depends on the recorded variable. Examples in which the choice of observables is critical are discussed and the level of information contained in a given variable is quantified in the case where the original system is known. A clear example of such a situation arises in the Rössler system for which the performance of a global vector field reconstruction technique is investigated using time series of variables x, y or z, taken one at a time.

  11. Alcatel-Space in hyper/multispectral Earth observation programs from MERIS to SPECTRA

    Science.gov (United States)

    Labandibar, Jean-Yves; Baudin, Gilles; Baillion, Yvan

    2004-02-01

    ALCATEL-SPACE has been involved for years in the development of highest performance space optical payload for Earth observation, notably in the domain of multi/super/hyperspectral observation, through the successful development of VEGETATION (for CNES) and MERIS (for ESA). The paper will analyse how the lessons of the development of MERIS are key benefits for the definition of the next generation hyperspectral payload of the ESA SPECTRA mission. It will highlight the areas where a direct heritage is applicable, such as the calibration strategy, and domains where technology progresses allow major evolutions, such as for instance in the definition of the payload's data processing architecture. SPECTRA (Surface Processes and Ecosystem Changes Through Response Analysis) is one of the three candidate missions in the ESA Earth Core Explorer program of research oriented missions that is currently under phase A study. Its scientific objective is to describe, understand and model the role of terrestrial vegetation in the global carbon cycle and its response to climate variability under the increasing pressure of human activity.

  12. Space time disaggregation of precipitation using daily precipitation and radar observations.

    Science.gov (United States)

    Bàrdossy, Andràs; Pegram, Geoffrey

    2016-04-01

    Radar measurements provide useful information on the spatial and temporal distribution of precipitation. Unfortunately the measurements are often erroneous and biased. Traditional raingauge based observations offer point values. The purpose of this contribution is to investigate the possibility of combining high frequency pluviometer rainfall observations, daily data and radar measurements to obtain sets of possible realizations of the "real" space-time distribution of precipitation. The stochastic model uses space-time copulas, and simulates realizations using a random mixing approach. The method does not intend to provide a single best estimate, but instead to generate many realizations of precipitation fields using the stochastic model. The realizations reflect the different sources of information and represent the corresponding uncertainty. Different levels of information derived from considering radar data are investigated starting with the use of (i) radar zeros only, then (ii) intensity classes and (iii) rank based combinations. The methods are tested and compared on selected events recorded by a dense radar network in South-West Germany, which has been carefully bias corrected.

  13. Spatial distribution of water in the stratosphere of Jupiter from observations with the Herschel space observatory

    Science.gov (United States)

    Cavalié, T.; Feuchtgruber, H.; Lellouch, E.; de Val-Borro, M.; Jarchow, C.; Moreno, R.; Hartogh, P.; Orton, G.; Greathouse, T. K.; Billebaud, F.; Dobrijevic, M.; Lara, L. M.; Gonzalez, A.; Sagawa, H.

    2013-09-01

    Water in the atmospheres of the outer planets has both an internal and an external source (e.g., [1] and [2] for Jupiter). These sources are separated by a condensation layer, the tropopause cold trap, which acts as a transport barrier between the troposphere and the stratosphere. Thus, the water vapor observed by the Infrared Space Observatory (ISO) in the stratosphere of the giant planets has an external origin [3]. This external supply of water may have several sources: (i) a permanent flux from interplanetary dust particles produced from asteroid collisions and from comet activity [4], (ii) local sources from planetary environments (rings, satellites) [5], (iii) cometary "Shoemaker-Levy 9 (SL9) type" impacts [6]. In the past 15 years, several studies suggested that water in the stratosphere of Jupiter originated from the SL9 comet impacts in July 1994, but a direct proof was missing. We will report the first high S/N spatially resolved mapping observations of water in Jupiter's stratosphere carried out with the Heterodyne Instrument for the Far Infrared (HIFI) [7] and Photodetector Array Camera and Spectrometer (PACS) [8] instruments onboard the ESA Herschel Space Observatory [9]. These observations have been obtained in the framework of the Guaranteed Time Key Program "Water and related chemistry in the Solar System", also known as "Herschel Solar System Observations" (HssO) [10]. In parallel, we have monitored Jupiter's stratospheric temperature with the NASA Infrared Telescope Facility (IRTF) to separate temperature from water variability. We will present the results recently published by our team [11]. Water is found to be restricted to pressures lower than 2mbar. Its column density decreases by a factor of 2-3 between southern and northern latitudes (see Fig. 1), consistently between the HIFI and the PACS 66.4μm maps. Latitudinal temperature variability cannot explain the global north-south asymmetry in the water maps. From the latitudinal and vertical

  14. Observed Coupling Between the International Space Station PCU Plasma and a FPMU Langmuir Probe Facilitated by the Geomagnetic Field

    Science.gov (United States)

    Hartman, William; Koontz, Steven L.

    2010-01-01

    Electrical charging of the International Space Station (ISS) is a matter of serious concern resulting from the possibility of vehicle arcing and electrical shock hazard to crew during extravehicular activity (EVA). A Plasma Contactor Unit (PCU) was developed and integrated into ISS in order to control the ISS floating potential, thereby, minimize vehicle charging and associated hazards. One of the principle factors affecting ISS electrical charging is the ionosphere plasma state (i.e., electron temperature and density). To support ISS electrical charging studies a Floating Potential Monitoring Unit (FPMU) is also integrated into ISS in order to measure the ionosphere properties using Langmuir probes (LP). The FPMU was located on the Starboard side of ISS. The PCU is located near the center of ISS with its plasma exhaust pointed to port. From its integration on ISS in 2006 through November of 2009, the FPMU data exhibited nominal characteristics during PCU operation. On November 21, 2009 the FPMU was relocated from the Starboard location to a new Port location. After relocation significant enhanced noise was observed in both the LP current-voltage sweeps and the derived electron temperature data. The enhanced noise only occurred when the PCU was in discharge and at unique and repeatable locations of the ISS orbit. The cause of this enhanced noise was investigated. It was found that there is coupling occurring between the PCU plasma and the FPMU LP. In this paper we shall 1) present the on-orbit data and the presence of enhanced noise, 2) demonstrate that the coupling of the PCU plasma and the FPMU measurements is geomagnetically organized, 3) show that coupling of the PCU plasma and the FPMU is primarily due to and driven by particle-wave interaction and 4) show that the ionosphere conditions are adequate for Alfven waves to be generated by the PCU plasma.

  15. Deployment Repeatability

    Science.gov (United States)

    2016-08-31

    potential future space-based mission through large-scale, ground-based testing. Full-scale deployment testing of two petal segments combined with...capture data for incorporation into larger analysis models. Stability testing of two full-scale composite strongback segments , including in a relevant...errors. The NuSTAR project opted for a metrology and adjustment system, which had many advantages for the project and few disadvantages . Because a

  16. The impact of FORMOSAT-5/AIP observations on the ionospheric space weather

    Directory of Open Access Journals (Sweden)

    Chia-Hung Chen

    2017-01-01

    Full Text Available This paper assimilates the in-situ O+ fluxes observations obtained from the Advanced Ionospheric Probe (AIP onboard the upcoming FORMOSAT-5 (FS-5 satellite and evaluates its possible impact on the ionospheric space weather forecast model. The Observing System Simulation Experiment (OSSE, designed for the global O+ fluxes, is shown to improve the electron density specification in the vicinity of satellite orbits. The root-mean-square-error (RMSE of the ionospheric electron density obtained from assimilating the daytime O+ fluxes could be improved by ~10 and ~5% for the forecast and nowcast, respectively. Although the improvement of nighttime O+ flux assimilation is less significant compared to the daytime assimilation, it still reveals impacts on the model result. This suggests that nighttime observations might not be sufficient to alter the model trajectory in the positive direction as with the daytime result. Alternative data assimilation approaches, such as assimilation of the empirical model built by using the nighttime FS-5/AIP together with other existing satellite observations of O+ flux could obtain better accuracy of the electron density forecast.

  17. Transferring Knowledge from a Bird's-Eye View - Earth Observation and Space Travels in Schools

    Science.gov (United States)

    Rienow, Andreas; Hodam, Henryk; Menz, Gunter; Voß, Kerstin

    2014-05-01

    In spring 2014, four commercial cameras will be transported by a Dragon spacecraft to the International Space Station (ISS) and mounted to the ESA Columbus laboratory. The cameras will deliver live earth observation data from different angles. The "Columbus-Eye"* project aims at distributing the video and image data produced by those cameras through a web portal. It should primary serve as learning portal for pupils comprising teaching material around the ISS earth observation imagery. The pupils should be motivated to work with the images in order to learn about curriculum relevant topics of natural sciences. The material will be prepared based on the experiences of the FIS* (German abbreviation for "Remote Sensing in Schools") project and its learning portal. Recognizing that in-depth use of satellite imagery can only be achieved by the means of computer aided learning methods, a sizeable number of e-Learning contents in German and English have been created throughout the last 5 years since FIS' kickoff. The talk presents the educational valorization of remote sensing data as well as their interactive implementation for teachers and pupils in both learning portals. It will be shown which possibilities the topic of remote sensing holds ready for teaching the regular curricula of Geography, Biology, Physics, Math and Informatics. Beside the sequenced implementation into digital and interactive teaching units, examples of a richly illustrated encyclopedia as well as easy-to-use image processing tools are given. The presentation finally addresses the question of how synergies of space travels can be used to enhance the fascination of earth observation imagery in the light of problem-based learning in everyday school lessons.

  18. Coordinated Observations of Space Debris as Optimisation Problem of Inter-Dependent Metrics

    Science.gov (United States)

    Sciotti, M.; Charlish, A.

    2013-08-01

    Optimal allocation of sensor resources is addressed in this paper in the frame of space surveillance application. Inspiration is taken from the optimal management of multi-functional sensors and netted surveillance sensors, for which the Sensor Management problem is often addressed as a Markov Decision Process. This approach allows determining the optimal decision at each discrete time instant by quantifying the expected payoff coming from the selected action. An action might be the assignment of the i -th surveillance task to the m -th sensor in the network ('tasking'), the selection of the i -th task at the k -th time slot ('scheduling'), or the activation of a specific sensor configuration for the completion of the i -th task ('resource allocation'). The common objective is the maximization of the global reward coming from the selected sequence of actions over a finite or infinite time horizon. This leads to a sequence of coordinated observations carried out by the sensor(s), which are determined statically or dynamically by the Sensor Manager. In this paper, the allocation of space surveillance resources is analysed as a management problem for sensor(s) with finite resources. The proposed allocation is driven by the operational requirements for space objects cataloguing, such as the object population coverage and the track accuracy. A sequential resource allocation strategy is formulated in order to cope with such inter-dependent, concurring performance metrics. The approach can be also extended to multiple sensors with different performance or nature. Promising results are demonstrated over a phased array radar case study.

  19. In-situ Observations of the Ionospheric F2-Region from the International Space Station

    Science.gov (United States)

    Coffey, Victoria N.; Wright, Kenneth H.; Minow, Joseph I.; Chandler, Michael O.; Parker, Linda N.

    2008-01-01

    The International Space Station orbit provides an ideal platform for in-situ studies of space weather effects on the mid and low latitude F-2 region ionosphere. The Floating Potential Measurement Unit (FPMU) operating on the ISS since Aug 2006, is a suite of plasma instruments: a Floating Potential Probe (FPP), a Plasma Impedance Probe (PIP), a Wide-sweep Langmuir Probe (WLP), and a Narrow-sweep Langmuir Probe (NLP). This instrument package provides a new opportunity for collaborative multi-instrument studies of the F-region ionosphere during both quiet and disturbed periods. This presentation first describes the operational parameters for each of the FPMU probes and shows examples of an intra-instrument validation. We then show comparisons with the plasma density and temperature measurements derived from the TIMED GUVI ultraviolet imager, the Millstone Hill ground based incoherent scatter radar, and DIAS digisondes, Finally we show one of several observations of night-time equatorial density holes demonstrating the capabilities of the probes for monitoring mid and low latitude plasma processes.

  20. Crop Production for Advanced Life Support Systems - Observations From the Kennedy Space Center Breadboard Project

    Science.gov (United States)

    Wheeler, R. M.; Sager, J. C.; Prince, R. P.; Knott, W. M.; Mackowiak, C. L.; Stutte, G. W.; Yorio, N. C.; Ruffe, L. M.; Peterson, B. V.; Goins, G. D.

    2003-01-01

    The use of plants for bioregenerative life support for space missions was first studied by the US Air Force in the 1950s and 1960s. Extensive testing was also conducted from the 1960s through the 1980s by Russian researchers located at the Institute of Biophysics in Krasnoyarsk, Siberia, and the Institute for Biomedical Problems in Moscow. NASA initiated bioregenerative research in the 1960s (e.g., Hydrogenomonas) but this research did not include testing with plants until about 1980, with the start of the Controlled Ecological Life Support System (CELSS) Program. The NASA CELSS research was carried out at universities, private corporations, and NASA field centers, including Kennedy Space Center (KSC). The project at KSC began in 1985 and was called the CELSS Breadboard Project to indicate the capability for plugging in and testing various life support technologies; this name has since been dropped but bioregenerative testing at KSC has continued to the present under the NASA s Advanced Life Support (ALS) Program. A primary objective of the KSC testing was to conduct pre-integration tests with plants (crops) in a large, atmospherically closed test chamber called the Biomass Production Chamber (BPC). Test protocols for the BPC were based on observations and growing procedures developed by university investigators, as well as procedures developed in plant growth chamber studies at KSC. Growth chamber studies to support BPC testing focused on plant responses to different carbon dioxide (CO2) concentrations, different spectral qualities from various electric lamps, and nutrient film hydroponic culture techniques.

  1. Hubble Space Telescope observations of Europa in and out of eclipse

    Science.gov (United States)

    Sparks, W.B.; McGrath, M.; Hand, K.; Ford, H.C.; Geissler, P.; Hough, J.H.; Turner, E.L.; Chyba, C.F.; Carlson, R.; Turnbull, M.

    2010-01-01

    Europa is a prime target for astrobiology and has been prioritized as the next target for a National Aeronautics and Space Administration flagship mission. It is important, therefore, that we advance our understanding of Europa, its ocean and physical environment as much as possible. Here, we describe observations of Europa obtained during its orbital eclipse by Jupiter using the Hubble Space Telescope. We obtained Advanced Camera for Surveys Solar Blind Channel far ultraviolet low-resolution spectra that show oxygen line emission both in and out of eclipse. We also used the Wide-Field and Planetary Camera-2 and searched for broad-band optical emission from fluorescence of the surface material, arising from the very high level of incident energetic particle radiation on ices and potentially organic substances. The high-energy particle radiation at the surface of Europa is extremely intense and is responsible for the production of a tenuous oxygen atmosphere and associated FUV line emission. Approximately 50% of the oxygen emission lasts at least a few hours into the eclipse. We discuss the detection limits of the optical emission, which allow us to estimate the fraction of incident energy reradiated at optical wavelengths, through electron-excited emission, Cherenkov radiation in the ice and fluorescent processes. ?? 2010 Cambridge University Press.

  2. Induced polarization dependence on pore space geometry: Empirical observations and mechanistic predictions

    Science.gov (United States)

    Weller, A.; Slater, L. D.

    2015-12-01

    We use an extensive database to compare empirical observations and previously proposed empirical models against recently developed mechanistic formulations for the induced polarization (IP) response in porous media as a function of pore space geometry and interfacial chemistry. These comparisons support the argument that the pore-volume normalized internal surface (Spor) is the most important geometric parameter influencing the polarization. The specific polarizability derived from the empirical relationship between imaginary conductivity σ″ and Spor is independent of the porosity. By contrast, equivalent specific polarizability terms in recently proposed mechanistic models are found to be significantly correlated with porosity, and thus do not appear to represent an interfacial chemistry factor independent of the pore space geometry. Furthermore, the database shows no evidence for a significant decrease in the counterion mobility of clayey materials relative to clay-free materials, as postulated in recent studies. On the contrary, a single value of cp is consistent with no significant differences in ionic mobility given that all samples were saturated with a NaCl solution close to a common salinity of about 100 mS/m.

  3. New Hubble Space Telescope Observations of Heavy Elements in Four Metal-Poor Stars

    CERN Document Server

    Roederer, Ian U; Sobeck, Jennifer S; Beers, Timothy C; Cowan, John J; Frebel, Anna; Ivans, Inese I; Schatz, Hendrik; Sneden, Christopher; Thompson, Ian B

    2012-01-01

    Elements heavier than the iron group are found in nearly all halo stars. A substantial number of these elements, key to understanding neutron-capture nucleosynthesis mechanisms, can only be detected in the near-ultraviolet. We report the results of an observing campaign using the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope to study the detailed heavy element abundance patterns in four metal-poor stars. We derive abundances or upper limits from 27 absorption lines of 15 elements produced by neutron-capture reactions, including seven elements (germanium, cadmium, tellurium, lutetium, osmium, platinum, and gold) that can only be detected in the near-ultraviolet. We also examine 202 heavy element absorption lines in ground-based optical spectra obtained with the Magellan Inamori Kyocera Echelle Spectrograph on the Magellan-Clay Telescope at Las Campanas Observatory and the High Resolution Echelle Spectrometer on the Keck I Telescope on Mauna Kea. We have detected up to 34 elements hea...

  4. A Ground-Based Array to Observe Geospace Electrodynamics During Adverse Space Weather Conditions

    Science.gov (United States)

    Sojka, J. J.; Eccles, J. V.; Rice, D.

    2004-05-01

    Geomagnetic Storms occur with surprising frequency and create adverse space weather conditions. During these periods, our knowledge and ability to specify or forecast in adequate detail for user needs is negligible. Neither experimental observations nor theoretical developments have made a significant new impact on the problem for over two decades. Although we can now map Total Electron Content (TEC) in the ionosphere over a continent with sufficient resolution to see coherent long-lived structures, these do not provide constraints on the geospace electrodynamics that is at the heart of our lack of understanding. We present arguments for the need of a continental deployment of ground-based sensors to stepwise advance our understanding of the geospace electrodynamics when it is most adverse from a space weather perspective and also most frustrating from an understanding of Magnetosphere-Ionosphere coupling. That a continental-scale deployment is more productive at addressing the problem than a realizable global distribution is shown. Each measurement is discussed from the point-of-view of either providing new knowledge or becoming a key for future real-time specification and forecasting for user applications. An example of a storm database from one mid-latitude station for the 31 March 2002 is used as a conceptual point in a ground-based array. The presentation focuses on scientific questions that have eluded a quantitative solution for over three decades and view a ground-based array as an "IGY" type of catalyst for answering these questions.

  5. Hubble Space Telescope Observations of Active Asteroid 324P/La Sagra

    CERN Document Server

    Jewitt, David; Weaver, Harold; Mutchler, Max; Li, Jing; Larson, Stephen

    2016-01-01

    Hubble Space Telescope observations of active asteroid 324P/La Sagra near perihelion show continued mass loss consistent with the sublimation of near-surface ice. Isophotes of the coma measured from a vantage point below the orbital plane are best matched by steady emission of particles having a nominal size $a \\sim$ 100 $\\mu$m. The inferred rate of mass loss, $dM_d/dt \\sim$0.2 kg s$^{-1}$, can be supplied by sublimation of water ice in thermal equilibrium with sunlight from an area as small as 930 m$^2$, corresponding to about 0.2\\% of the nucleus surface. Observations taken from a vantage point only 0.6\\degr~from the orbital plane of 324P set a limit to the velocity of ejection of dust in the direction perpendicular to the plane, $V_{\\perp} <$ 1 m s$^{-1}$. Short-term photometric variations of the near-nucleus region, if related to rotation of the underlying nucleus, rule out periods $\\le$ 3.8 hr and suggest that rotation probably does not play a central role in driving the observed mass loss. We estimat...

  6. The supersymmetric parameter space in light of B-physics observables and electroweak precision data

    Science.gov (United States)

    Ellis, John; Heinemeyer, Sven; Olive, Keith A.; Weber, Arne M.; Weiglein, Georg

    2007-08-01

    Indirect information about the possible scale of supersymmetry (SUSY) breaking is provided by B-physics observables (BPO) as well as electroweak precision observables (EWPO). We combine the constraints imposed by recent measurements of the BPO BR(b → sγ), BR(Bs → μ+μ-), BR(Bu → τντ) and ΔMBs with those obtained from the experimental measurements of the EWPO MW, sin2 θeff, ΓZ, (g-2)μ and Mh, incorporating the latest theoretical calculations of these observables within the Standard Model and supersymmetric extensions. We perform a χ2 fit to the parameters of the constrained minimal supersymmetric extension of the Standard Model (CMSSM), in which the SUSY-breaking parameters are universal at the GUT scale, and the non-universal Higgs model (NUHM), in which this constraint is relaxed for the soft SUSY-breaking contributions to the Higgs masses. Assuming that the lightest supersymmetric particle (LSP) provides the cold dark matter density preferred by WMAP and other cosmological data, we scan over the remaining parameter space. Within the CMSSM, we confirm the preference found previously for a relatively low SUSY-breaking scale, though there is some slight tension between the EWPO and the BPO. In studies of some specific NUHM scenarios compatible with the cold dark matter constraint we investigate (MA, tan β) planes and find preferred regions that have values of χ2 somewhat lower than in the CMSSM.

  7. Spitzer Space Telescope Observations of Kepler's Supernova Remnant: A Detailed Look at the Circumstellar Dust Component

    CERN Document Server

    Blair, W P; Long, K S; Williams, B J; Borkowski, K J; Sankrit, S P R R; Blair, William P.; Ghavamian, Parviz; Long, Knox S.; Williams, Brian J.; Borkowski, Kazimierz J.; Sankrit, Stephen P. Reynolds & Ravi

    2007-01-01

    We present 3.6 - 160 micron infrared images of Kepler's supernova remnant (SN1604) obtained with the IRAC and MIPS instruments on the Spitzer Space Telescope. We also present MIPS SED low resolution spectra in the 55 - 95 micron region. The observed emission in the MIPS 24 micron band shows the entire shell. Emission in the MIPS 70 micron and IRAC 8 micron bands is seen only from the brightest regions of 24 micron emission, which also correspond to the regions seen in optical Halpha images. Shorter wavelength IRAC images are increasingly dominated by stars, although faint filaments are discernible. The SED spectrum of shows a faint continuum dropping off to longer wavelengths and confirms that strong line emission does not dominate the mid-IR spectral region. The emission we see is due primarily to warm dust emission from dust heated by the primary blast wave; no excess infrared emission is observed in regions where supernova ejecta are seen in X-rays. We use models of the dust to interpret the observed 70/24...

  8. Real space channelization for generic DBT system image quality evaluation with channelized Hotelling observer

    Science.gov (United States)

    Petrov, Dimitar; Cockmartin, Lesley; Marshall, Nicholas; Vancoillie, Liesbeth; Young, Kenneth; Bosmans, Hilde

    2017-03-01

    Digital breast tomosynthesis (DBT) is a relatively new 3D mammography technique that promises better detection of low contrast masses than conventional 2D mammography. The parameter space for DBT is large however and finding an optimal balance between dose and image quality remains challenging. Given the large number of conditions and images required in optimization studies, the use of human observers (HO) is time consuming and certainly not feasible for the tuning of all degrees of freedom. Our goal was to develop a model observer (MO) that could predict human detectability for clinically relevant details embedded within a newly developed structured phantom for DBT applications. DBT series were acquired on GE SenoClaire 3D, Giotto Class, Fujifilm AMULET Innovality and Philips MicroDose systems at different dose levels, Siemens Inspiration DBT acquisitions were reconstructed with different algorithms, while a larger set of DBT series was acquired on Hologic Dimensions system for first reproducibility testing. A channelized Hotelling observer (CHO) with Gabor channels was developed The parameters of the Gabor channels were tuned on all systems at standard scanning conditions and the candidate that produced the best fit for all systems was chosen. After tuning, the MO was applied to all systems and conditions. Linear regression lines between MO and HO scores were calculated, giving correlation coefficients between 0.87 and 0.99 for all tested conditions.

  9. Deciphering IR Excess Observed by the Spitzer Space Telescope in Short Period Interacting Cataclysmic Binaries

    Science.gov (United States)

    Chun, Howard; Brinkworth, Carolyn; Ciardi, David; Hoard, Don; Howell, Steve; Stefaniak, Linda; Thomas, , Beth

    2006-03-01

    During the first year of the Spitzer Space Telescope Observing Program for Students and Teachers, our team observed a small sample of short orbital period interacting white dwarf binaries. Our scientific investigation was aimed at detection and characterization of the low mass, cool, brown dwarf-like mass donors in these systems. We used the Infrared Array Camera to obtain photometric observations of the polars EF Eri, GG Leo, V347 Pav, and RX J0154.0-5947 at 3.6, 4.5, 5.8, and 8.0 microns. In all our targets, we detected excess emission in the 3-8 micron region over that expected from a brown dwarf alone. One of the exciting discoveries we made with our IRAC observations is that the star EF Eri was found to be unexpectedly bright in the mid-IR (compared to its 2MASS magnitudes). This fact highlights an opportunity for us to observe EF Eri with the IRS as a follow-up proposal. EF Eri has a flux level of ~700 ?Jy at 8 microns. Thus, we are asking for time to obtain IRS data for only this star, our brightest source. We plan to obtain SL1 (7.4-14.5 microns) and SL2 (5.2-8.7 microns) spectroscopy only. We know the IRAC fluxes so our integration toies are well constrained and the spectral region covered by SL1, SL2 will yield sufficient S/N to differentiate between cool dust (rising BB like spectrum with PAH and other molecular features allowing us to determine dust size, temperature, and disk extent) and a T type dwarf showing characteristic spectral signatures and a falling Rayleigh-Jeans tail.

  10. Observations of a Unique Type of ULF Waves by Low-Latitude Space Technology 5 Satellites

    Science.gov (United States)

    Le, G.; Chi, P. J.; Strangeway, R. J.; Slavin, J. A.

    2011-01-01

    We report a unique type of ULF waves observed by low-altitude Space Technology 5 (ST-5) constellation mission. ST-5 is a three micro-satellite constellation deployed into a 300 x 4500 km, dawn-dusk, and sun synchronous polar orbit with 105.6deg inclination angle. Due to the Earth s rotation and the dipole tilt effect, the spacecraft s dawn-dusk orbit track can reach as low as subauroral latitudes during the course of a day. Whenever the spacecraft traverse across the dayside closed field line region at subauroral latitudes, they frequently observe strong transverse oscillations at 30-200 mHz, or in the Pc 2-3 frequency range. These Pc 2-3 waves appear as wave packets with durations in the order of 5-10 minutes. As the maximum separations of the ST-5 spacecraft are in the order of 10 minutes, the three ST-5 satellites often observe very similar wave packets, implying these wave oscillations occur in a localized region. The coordinated ground-based magnetic observations at the spacecraft footprints, however, do not see waves in the Pc 2-3 band; instead, the waves appear to be the common Pc 4-5 waves associated with field line resonances. We suggest that this unique Pc 2-3 waves seen by ST-5 are in fact the Doppler-shifted Pc 4-5 waves as a result of rapid traverse of the spacecraft across the resonant field lines azimuthally at low altitudes. The observations with the unique spacecraft dawn-disk orbits at proper altitudes and magnetic latitudes reveal the azimuthal characteristics of field-aligned resonances.

  11. Observations of a Unique Type of ULF Waves by Low-Latitude Space Technology Five Mission

    Science.gov (United States)

    Le, G.; Chi, P.; Strangeway, R. J.; Slavin, J. A.

    2011-01-01

    We report a unique type of ULF waves observed by low-altitude Space Technology 5 (ST-5) constellation mission. ST-5 is a three micro-satellite constellation deployed into a 300 x 4500 km, dawn-dusk, and sun synchronous polar orbit with 105.6deg inclination angle. Due to the Earth s rotation and the dipole tilt effect, the spacecraft s dawn-dusk orbit track can reach as low as subauroral latitudes during the course of a day. Whenever the spacecraft traverse across the dayside closed field line region at subauroral latitudes, they frequently observe strong transverse oscillations at 30-200 mHz, or in the Pc 2-3 frequency range. These Pc 2-3 waves appear as wave packets with durations in the order of 5-10 minutes. As the maximum separations of the ST-5 spacecraft are in the order of 10 minutes, the three ST-5 satellites often observe very similar wave packets, implying these wave oscillations occur in a localized region. The coordinated ground-based magnetic observations at the spacecraft footprints, however, do not see waves in the Pc 2-3 band; instead, the waves appear to be the common Pc 4-5 waves associated with field line resonances. We suggest that these unique Pc 2-3 waves seen by ST-5 are in fact the Doppler-shifted Pc 4-5 waves as a result of rapid traverse of the spacecraft across the resonant field lines azimuthally at low altitudes. The observations with the unique spacecraft dawn-disk orbits at proper altitudes and magnetic latitudes reveal the azimuthal characteristics of field-aligned resonances.

  12. Observations of a Unique Type of ULF Waves by Low-Latitude Space Technology 5 Mission

    Science.gov (United States)

    Le, Guan; Chi, P.; Strangeway, R. J.; Slavin, J. A.

    2011-01-01

    We report a unique type of ULF waves observed by low-altitude Space Technology 5 (ST-5) constellation mission. ST-5 is a three micro-satellite constellation deployed into a 300 x 4500 km, dawn-dusk, and sun synchronous polar orbit with 105.6 inclination angle. Due to the Earth's rotation and the dipole tilt effect, the spacecraft's dawn-dusk orbit track can reach as low as sub auroral latitudes during the course of a day. Whenever the spacecraft traverse across the dayside closed field line region at sub auroral latitudes, they frequently observe strong transverse oscillations at 30-200 mHz, or in the Pc 2-3 frequency range. These Pc 2-3 waves appear as wave packets with durations in the order of 5-10 minutes. As the maximum separations of the ST-5 spacecraft are in the order of 10 minutes, the three ST -5 satellites often observe very similar wave packets, implying these wave oscillations occur in a localized region. The coordinated ground-based magnetic observations at the spacecraft footprints, however, do not see waves in the Pc 2-3 band; instead, the waves appear to be the common Pc 4-5 waves associated with field line resonances. We suggest that these unique Pc 2-3 waves seen by ST-5 are in fact the Doppler-shifted Pc 4-5 waves as a result of rapid traverse of the spacecraft across the resonant field lines azimuthally at low altitudes. The observations with the unique spacecraft dawn-disk orbits at proper altitudes and magnetic latitudes reveal the azimuthal characteristics of field-aligned resonances.

  13. Observations of a Unique Type of ULF Wave by Low-Altitude Space Technology 5 Satellites

    Science.gov (United States)

    Le, G.; Chi, P. J.; Strangeway, R. J.; Slavin, J. A.

    2011-01-01

    We report a unique type of ULF waves observed by low-altitude Space Technology 5 (ST-5) constellation mission. ST-5 is a three-microsatellite constellation deployed into a 300 x 4500 km dawn-dusk and Sun-synchronous polar orbit with 105.6deg inclination angle. Because of the Earth's rotation and the dipole tilt effect, the spacecraft's dawn-dusk orbit track can reach as low as subauroral latitudes during the course of a day. Whenever the spacecraft traverse the dayside closed field line region at subauroral latitudes, they frequently observe strong transverse oscillations at 30-200 mHz, or in the Pc2-3 frequency range. These Pc2-3 waves appear as wave packets with durations in the order of 5-10 min. As the maximum separations of the ST-5 spacecraft are in the order of 10 min, the three ST-5 satellites often observe very similar wave packets, implying these wave oscillations occur in a localized region. The coordinated ground-based magnetic observations at the spacecraft footprints, however, do not see waves in the Pc2-3 band; instead, the waves appear to be the common Pc4-5 waves associated with field line resonances. We suggest that these unique Pc2-3 waves seen by ST-5 are in fact the Doppler-shifted Pc4-5 waves as a result of rapid traverse of the spacecraft across the resonant field lines azimuthally at low altitudes. The observations with the unique spacecraft dawn-dusk orbits at proper altitudes and magnetic latitudes reveal the azimuthal characteristics of field line resonances.

  14. Online variational inference for state-space models with point-process observations.

    Science.gov (United States)

    Mangion, Andrew Zammit; Yuan, Ke; Kadirkamanathan, Visakan; Niranjan, Mahesan; Sanguinetti, Guido

    2011-08-01

    We present a variational Bayesian (VB) approach for the state and parameter inference of a state-space model with point-process observations, a physiologically plausible model for signal processing of spike data. We also give the derivation of a variational smoother, as well as an efficient online filtering algorithm, which can also be used to track changes in physiological parameters. The methods are assessed on simulated data, and results are compared to expectation-maximization, as well as Monte Carlo estimation techniques, in order to evaluate the accuracy of the proposed approach. The VB filter is further assessed on a data set of taste-response neural cells, showing that the proposed approach can effectively capture dynamical changes in neural responses in real time.

  15. Numerical Identification of Multiparameters in the Space Fractional Advection Dispersion Equation by Final Observations

    Directory of Open Access Journals (Sweden)

    Dali Zhang

    2012-01-01

    Full Text Available This paper deals with an inverse problem for identifying multiparameters in 1D space fractional advection dispersion equation (FADE on a finite domain with final observations. The parameters to be identified are the fractional order, the diffusion coefficient, and the average velocity in the FADE. The forward problem is solved by a finite difference scheme, and then an optimal perturbation regularization algorithm is introduced to determine the three parameters simultaneously. Numerical inversions are performed both with the accurate data and noisy data, and several factors having influences on realization of the algorithm are discussed. The inversion solutions are in good approximations to the exact solutions demonstrating the efficiency of the proposed algorithm.

  16. Further observations of Space Shuttle plasma-electrodynamic effects from OSS-1/STS-3

    Science.gov (United States)

    Stone, N. H.; Hwang, K. S.; Wright, K. H., Jr.; Samir, U.; Murphy, G. B.; Shawhan, S. D.

    1986-01-01

    Recent analyses of ion measurements obtained from the Differential Ion Flux Probe (DIFP) on the deployed Plasma Diagnostics Package (PDP) during the OSS-1/STS-3 mission have provided an additional insight into the plasma-electrodynamics of the Space Shuttle Orbiter: (1) Measured ion flow directions and energies suggest that the disturbance created in the ionospheric plasma by the Shuttle Orbiter may be confined to an interaction region that extends on the order of 10 m in the forward direction and has a boundary thickness of about 2 m. (2) A correlation between the DIFP and pressure gauge measurements indicates a direct, local proportionality between the neutral gas and ion densities. (3) Preliminary results from a theoretical model of the possible interaction between measured secondary, high inclination ion streams and the ambient plasma indicate the generation of broad-band electrostatic noise such as that observed by wave instruments on the PDP.

  17. Observation of the exhaust plume from the space shuttle main engine using the Microwave Limb Sounder

    Directory of Open Access Journals (Sweden)

    H. C. Pumphrey

    2010-08-01

    Full Text Available A space shuttle launch deposits 700 t of water in the atmosphere. Some of this water is released into the upper mesosphere and lower thermosphere where it may be directly detected by a limb sounding satellite instrument. We report measurements of water vapour plumes from shuttle launches made by the Microwave Limb Sounder (MLS on the Aura satellite. Approximately 50% of shuttle launches are detected by MLS. The signal appears at a similar level across the upper 10 km of the MLS limb scan, suggesting that the bulk of the observed water is above the top of the scan. Only a small fraction at best of smaller launches (Ariane, Proton are detected. We conclude that the sensitivity of MLS is only just great enough to detect a shuttle sized launch, but that a suitably designed instrument of the same general type could detect the exhausts from a large proportion of heavy-lift launches.

  18. Observation of the exhaust plume from the space shuttle main engines using the microwave limb sounder

    Directory of Open Access Journals (Sweden)

    H. C. Pumphrey

    2011-01-01

    Full Text Available A space shuttle launch deposits 700 tonnes of water in the atmosphere. Some of this water is released into the upper mesosphere and lower thermosphere where it may be directly detected by a limb sounding satellite instrument. We report measurements of water vapour plumes from shuttle launches made by the Microwave Limb Sounder (MLS on the Aura satellite. Approximately 50%–65% of shuttle launches are detected by MLS. The signal appears at a similar level across the upper 10 km of the MLS limb scan, suggesting that the bulk of the observed water is above the top of the scan. Only a small fraction at best of smaller launches (Ariane 5, Proton are detected. We conclude that the sensitivity of MLS is only just great enough to detect a shuttle sized launch, but that a suitably designed instrument of the same general type could detect the exhausts from a large proportion of heavy-lift launches.

  19. Mesosphere and Lower Thermosphere Winds from space: A decade and a half of observations

    Science.gov (United States)

    Skinner, W. R.; Niciejewski, R.; Gell, D. A.; Cooper, M.; Marshall, A. R.; Solomon, S. C.; Wu, Q.; Killeen, T. L.; Ortland, D. A.

    2006-05-01

    Continuous space borne observations of the mesosphere and lower thermosphere wind field have now been made for more than 14 years. Wind measurements commenced in late 1991 with two wind sensing instrument on the UARS spacecraft (HRDI and WINDII) and continue to the present with the TIDI instrument on TIMED. The HRDI and WINDII instruments operated simultaneously during much of the operational life of UARS and have been extensively validated. Both TIDI and HRDI obtained measurements from 2002 to 2005 providing a very desirable three year overlap to cross calibrate the instruments. The length of this combined data set permits study of the inter-annual variability of this part of the atmosphere. This paper discusses some of longer term phenomena that have been studied.

  20. Spitzer Space Telescope Observations of Low Mass X-ray Binaries

    CERN Document Server

    Wachter, Stefanie

    2008-01-01

    We present preliminary results from our archival Spitzer Space Telescope program aimed at characterizing the mid-IR properties of compact objects, both isolated and in binary systems, i.e. white dwarfs, X-ray binaries, cataclysmic variables, and magnetars. Most of these sources are too faint at mid-IR wavelengths to be observable from the ground, so this study provides the very first comprehensive look at the mid-IR emission of these objects. Here we present our results for the low mass X-ray binaries. We considered all of the systems listed in the most recent catalog of Liu et al. (2007) that have known optical counterparts. The particular goals of our projects encompass: to establish the mid-IR spectral energy distribution, to search for the signatures of jets, circumbinary disks, low mass or planetary companions and debris disks, and to study the local environment of these sources.

  1. Vectorcardiographic changes during extended space flight (M093): Observations at rest and during exercise

    Science.gov (United States)

    Smith, R. F.; Stanton, K.; Stoop, D.; Brown, D.; Janusz, W.; King, P.

    1977-01-01

    The objectives of Skylab Experiment M093 were to measure electrocardiographic signals during space flight, to elucidate the electrophysiological basis for the changes observed, and to assess the effect of the change on the human cardiovascular system. Vectorcardiographic methods were used to quantitate changes, standardize data collection, and to facilitate reduction and statistical analysis of data. Since the Skylab missions provided a unique opportunity to study the effects of prolonged weightlessness on human subjects, an effort was made to construct a data base that contained measurements taken with precision and in adequate number to enable conclusions to be made with a high degree of confidence. Standardized exercise loads were incorporated into the experiment protocol to increase the sensitivity of the electrocardiogram for effects of deconditioning and to detect susceptability for arrhythmias.

  2. Explaining Phenomenologically Observed Space-time Flatness Requires New Fundamental Scale Physics

    CERN Document Server

    Bennett, D

    2013-01-01

    The phenomenologically observed flatness - or near flatness - of spacetime cannot be understood as emerging from continuum Planck (or sub-Planck) scales using known physics. Using dimensional arguments it is demonstrated that any immaginable action will lead to Christoffel symbols that are chaotic. We put forward new physics in the form of fundamental fields that spontaneously break translational invariance. Using these new fields as coordinates we define the metric in such a way that the Riemann tensor vanishes identically as a Bianchi identity. Hence the new fundamental fields define a flat space. General relativity with curvature is recovered as an effective theory at larger scales at which crystal defects in the form of disclinations come into play as the sources of curvature.

  3. The International Space Station as a Key Platform to Synergize Observations of Fundamental Ecosystem Properties

    Science.gov (United States)

    Fisher, J. B.; Stavros, E. N.; Pavlick, R.; Hook, S. J.; Eldering, A.; Dubayah, R.; Schimel, D.

    2016-12-01

    Terrestrial ecosystems can be described in terms of trait composition, physiological function, and physical structure; all three of these are observable remotely to varying degrees. Yet, no mission is able to singularly capture all three together, thus inhibiting our ability to dynamically measure and describe ecosystems as holistic, integrated, and interconnected entities. The International Space Station (ISS) is a new platform for global ecology. The variable overpass time offers a key advantage to investigations interested in sampling over the diurnal cycle, critical to understanding ecosystem function. The ISS also offers another key advantage—financial; it is already there with funded astronaut cargo re-supply missions, so the cost of launch and platform do not need to be added onto new science missions, thereby enabling NASA to select more missions at lower costs. In 2018, NASA will begin sending a series of independently-selected missions to the ISS focused on terrestrial ecosystems. First, ECOSTRESS will produce thermal-based evapotranspiration (ET) data, among other products. OCO-3 will arrive a few months later to measure chlorophyll fluorescence (related to gross primary production, GPP) and atmospheric CO2. Finally, GEDI will produce LiDAR-based ecosystem structure (height, leaf area index, biomass). While each mission is independently developed and funded, the respective mission scientists are working together to bridge observations and leverage their unique contemporaneous and synergistic value for global ecology. A composition-based mission is still missing from the ISS, but airborne and other space agency missions may be leveraged. This talk will describe these ISS-based terrestrial ecosystem science missions, and discuss synergies that will enable the study of ecosystems as a whole that is larger than the sum of their parts.

  4. ULF Waves Observed at MAGDAS Stations as Probes for Litho-Space Weather Study

    Science.gov (United States)

    Yumoto, Kiyohumi

    K.Yumoto, Space Environment Research Center (SERC), Kyushu University started the MAGDAS Project effectively in May of 2005, with the installation of the first unit in Hualien, Taiwan (Yumoto et al., 2006, 2007). Since then, over 50 units have been deployed around the world. They are concentrated along three chains: (1) North and South of Japan (the so-called "210o Magnetic Meridian Chain"), (2) Dip Equator Chain, and (3) Africa Chain (the so-called "96o Magnetic Meridian Chain"). The main goals of MAGDAS project are: (1) study magnetospheric pro-cesses by distinguishing between temporal changes and spatial variations in the phenomena, (2) clarify global structures and propagation characteristics of magnetospheric variations from higher to equatorial latitudes, and (3) understand global generation mechanisms of the Solar-Terrestrial phenomena (see Yumoto, 2004). From MAGDAS observations, ULF waves are found to be used as good probes for litho-space weather study in developing and developed countries. In the present paper, we will introduce the following examples: Pc 5 magnetic amplitudes at lower-latitude MAGDAS station show a linear relation with the solar wind velocity, thus we can use the Pc 5 amplitudes as a monitoring probe of the solar wind velocity. Pc 3-4 magnetic pulsations have skin depth comparable with the depth of epicentre of earthquakes in the lithosphere. Therefore, we can use Pc 3-4 as a probe for detecting ULF anomaly and precursors associated with great earthquakes. Pi 2 magnetic pulsations are observed globally at MAGDAS stations located at high, middle, low, and equatorial latitudes in night-and day-time. We can use the Pi 2s as a good indicator of onsets of magnetospheric substorms. Sudden commencements (sc), sudden impulse (si), and solar flare effects (sfe) create magnetic variations at MAGDAS stations. Therefore, MAGDAS data can be used as a probe of interplanetary shocks and interplanetary discontinuities in the solar wind, and solar flare

  5. NEW HUBBLE SPACE TELESCOPE OBSERVATIONS OF HEAVY ELEMENTS IN FOUR METAL-POOR STARS

    Energy Technology Data Exchange (ETDEWEB)

    Roederer, Ian U.; Thompson, Ian B. [Carnegie Observatories, Pasadena, CA 91101 (United States); Lawler, James E. [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Sobeck, Jennifer S. [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States); Beers, Timothy C. [National Optical Astronomy Observatory, Tucson, AZ 85719 (United States); Cowan, John J. [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, OK 73019 (United States); Frebel, Anna [Massachusetts Institute of Technology, Kavli Institute for Astrophysics and Space Research, Cambridge, MA 02139 (United States); Ivans, Inese I. [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Schatz, Hendrik [Department of Physics and Astronomy, Michigan State University, E. Lansing, MI 48824 (United States); Sneden, Christopher [Department of Astronomy, University of Texas at Austin, Austin, TX 78712 (United States)

    2012-12-15

    Elements heavier than the iron group are found in nearly all halo stars. A substantial number of these elements, key to understanding neutron-capture nucleosynthesis mechanisms, can only be detected in the near-ultraviolet. We report the results of an observing campaign using the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope to study the detailed heavy-element abundance patterns in four metal-poor stars. We derive abundances or upper limits from 27 absorption lines of 15 elements produced by neutron-capture reactions, including seven elements (germanium, cadmium, tellurium, lutetium, osmium, platinum, and gold) that can only be detected in the near-ultraviolet. We also examine 202 heavy-element absorption lines in ground-based optical spectra obtained with the Magellan Inamori Kyocera Echelle Spectrograph on the Magellan-Clay Telescope at Las Campanas Observatory and the High Resolution Echelle Spectrometer on the Keck I Telescope on Mauna Kea. We have detected up to 34 elements heavier than zinc. The bulk of the heavy elements in these four stars are produced by r-process nucleosynthesis. These observations affirm earlier results suggesting that the tellurium found in metal-poor halo stars with moderate amounts of r-process material scales with the rare earth and third r-process peak elements. Cadmium often follows the abundances of the neighboring elements palladium and silver. We identify several sources of systematic uncertainty that must be considered when comparing these abundances with theoretical predictions. We also present new isotope shift and hyperfine structure component patterns for Lu II and Pb I lines of astrophysical interest.

  6. Multicolor Photometric Observation of Lightning from Space: Comparison with Radio Measurements

    Science.gov (United States)

    Adachi, Toru; Cohen, Morris; Said, Ryan; Blakeslee, Richard J.; Cummer, Steven A.; Li, Jingbo; Lu, Geopeng; Hsu, Rue-Ron; Su, Han-Tzong; Chen, Alfred Bing-Chih; Takahashi, Yukihiro; Frey, Harald U.; Mende, Stephen B.

    2011-01-01

    This study evaluates the effectiveness of spectrophotometric measurements from space in revealing properties of lightning flash. The multicolor optical waveform data obtained by FORMOSAT-2/Imager of Sprites and Upper Atmospheric Lightning (ISUAL) were analyzed in relation to National Lightning Detection Network (NLDN), North Alabama Lightning Mapping Array (LMA). As of July 2011, we found six lightning events which were observed by ISUAL and North Alabama LMA. In two of these events, NLDN showed clear positive cloud-to-ground (CG) discharges with peak current of +139.9 kA and +41.6 kA and, around that time, LMA showed continuous intra-cloud (IC) leader activities at 4-6 km altitudes. ISUAL also observed consistent optical waveforms of the IC and CG components and, interestingly, it was found that the blue/red spectral ratio clearly decreased by a factor of 1.5-2.5 at the time of CG discharges. Other four lightning events in which NLDN did not detect any CG discharges were also investigated, but such a feature was not found in any of these cases. These results suggest that the optical color of CG component is more reddish than that of IC component and we explain this as a result of more effective Rayleigh scattering in blue light emissions coming from lower-altitude light source. This finding suggests that spectral measurements could be a new useful technique to characterize ICs and CGs from space. In this talk, we will also present a result from lightning statistical analysis of ISUAL spectrophotometric data and ULF magnetic data.

  7. Observing the Moon at Microwave Frequencies Using a Large-Diameter Deep Space Network Antenna

    Science.gov (United States)

    Morabito, David D.; Imbriale, William; Keihm, Stephen

    2008-03-01

    The Moon radiates energy at infrared and microwave wavelengths, in addition to reflecting sunlight at optical wavelengths. As a result, an antenna pointed at or near the Moon will result in an increase in system operating noise temperature, which needs to be accounted for in RF telecommunications, radio science or radiometric link calculations. The NASA Deep Space Network (DSN) may use its large-diameter antennas in future lunar robotic or human missions, and thus it is important to understand the nature of this temperature incre ase as a function of observing frequency, lunar phase, and angular position of the antenna beam on the lunar disk. This paper reports on a comprehensive lunar noise temperature measurement campaign and associated theoretical treatment for a 34-m diameter Deep Space Network antenna observing an extended source such as the Moon. A set of measurements over a wide range of lunar phase angles was acquired at DSS-13, a 34-m diameter beam waveguide antenna (BWG) located at Goldstone, California at 2.3 GHz (S-band), 8.4 GHz (X-band) and 32 GHz (Ka-band). For validation purposes, independent predictions of noise temperature increase were derived using a physical optics characterization of the 34-m diameter antenna gain patterns and Apollo model-based brightness temperature maps of the Moon as input. The model-based predictions of noise temperature increase were compared with the measurements at all three frequencies. In addition, a methodology is presented that relates noise temperature increase due to the Moon to disk-centered or disk-averaged brightness temperature of the Moon at the microwave frequencies of interest. Comparisons were made between the measurements and models in the domain of lunar disk-centered and disk-averaged brightness temperatures. It is anticipated that the measurements and associated theoretical development will be useful in developing telecommunications strategies for future high-rate Ka-band communications where large

  8. Gradient-like observer design on the Special Euclidean group SE(3) with system outputs on the real projective space

    OpenAIRE

    Hua, Minh-Duc; Hamel, Tarek; Mahony, Robert; Trumpf, Jochen

    2015-01-01

    A nonlinear observer on the Special Euclidean group $\\mathrm{SE(3)}$ for full pose estimation, that takes the system outputs on the real projective space directly as inputs, is proposed. The observer derivation is based on a recent advanced theory on nonlinear observer design. A key advantage with respect to existing pose observers on $\\mathrm{SE(3)}$ is that we can now incorporate in a unique observer different types of measurements such as vectorial measurements of known inertial vectors an...

  9. Using Eye Tracking to Observe Differential Effects of Repeated Readings for Second-grade Students as a Function of Achievement Level

    Science.gov (United States)

    Zawoyski, Andrea M.; Ardoin, Scott P.; Binder, Katherine S.

    2015-01-01

    Repeated readings (RR) is an evidence-based instructional technique in which students read the same text multiple times. Currently, little is known about how effects of RR may differ based on students' achievement levels. Eye tracking provides a means for closely examining instructional effects because it permits measurement of subtle changes that…

  10. Hubble Space Telescope Observations of Globular Clusters with Central Density Cusps

    Science.gov (United States)

    Sosin, Craig Anthony

    1997-07-01

    We use the Hubble Space Telescope to observe crowded fields in globular clusters with central density cusps, and use the observed stellar distributions to study the internal dynamics of clusters in advanced stages of evolution. We begin by discussing images of the cusp of NGC 6624. From the positions of individual stars, we measure the logarithmic slope of the central density cusp, but do not resolve the cluster core. We also detect a central population of blue stragglers, and compare the frequencies of such stars in several clusters. NGC 6397, as well as photometric techniques for use with diffraction-limited HST images. We measure logarithmic cusp slopes for various groups of main-sequence stars in each cluster; we also set upper limits on the core radii of M15 and M30, and measure a radius of ~5' for the NGC 6397 core. We compare mass functions (MFs) measured at several radii in each cluster, and find substantial mass segregation. In M30, the observed segregation is well matched by the predictions of a King-Michie model, but similar models of M15 and NGC 6397 predict more mass segregation than we observe. We then use the Jeans equation and our MFs to investigate the degree of equipartition of energy between stellar species in each cluster. We find that M30 is very close to equipartition over the observed radial range between the cusp and the envelope, while M15 and NGC 6397 are not. The difference between M30 and M15 might be explained by the difference in relaxation times at the observed radii, but this scenario fails to explain the NGC 6397 data. We discuss the possibility that post-collapse clusters remain subject to the Spitzer instability, and the possibility that the tidal shocks suffered by NGC 6397 have affected its degree of mass segregation. We also propose that the observed differences between the central cusps of the clusters could be due to gravothermal oscillations, to differences in binary populations, or to the presence of a ~103Msolar black hole

  11. Linking space observations to volcano observatories in Latin America: Results from the CEOS DRM Volcano Pilot

    Science.gov (United States)

    Delgado, F.; Pritchard, M. E.; Biggs, J.; Arnold, D. W. D.; Poland, M. P.; Ebmeier, S. K.; Wauthier, C.; Wnuk, K.; Parker, A. L.; Amelug, F.; Sansosti, E.; Mothes, P. A.; Macedo, O.; Lara, L.; Zoffoli, S.; Aguilar, V.

    2015-12-01

    Within Latin American, about 315 volcanoes that have been active in the Holocene, but according to the United Nations Global Assessment of Risk 2015 report (GAR15) 202 of these volcanoes have no seismic, deformation or gas monitoring. Following the 2012 Santorini Report on satellite Earth Observation and Geohazards, the Committee on Earth Observation Satellites (CEOS) has developed a 3-year pilot project to demonstrate how satellite observations can be used to monitor large numbers of volcanoes cost-effectively, particularly in areas with scarce instrumentation and/or difficult access. The pilot aims to improve disaster risk management (DRM) by working directly with the volcano observatories that are governmentally responsible for volcano monitoring, and the project is possible thanks to data provided at no cost by international space agencies (ESA, CSA, ASI, DLR, JAXA, NASA, CNES). Here we highlight several examples of how satellite observations have been used by volcano observatories during the last 18 months to monitor volcanoes and respond to crises -- for example the 2013-2014 unrest episode at Cerro Negro/Chiles (Ecuador-Colombia border); the 2015 eruptions of Villarrica and Calbuco volcanoes, Chile; the 2013-present unrest and eruptions at Sabancaya and Ubinas volcanoes, Peru; the 2015 unrest at Guallatiri volcano, Chile; and the 2012-present rapid uplift at Cordon Caulle, Chile. Our primary tool is measurements of ground deformation made by Interferometric Synthetic Aperture Radar (InSAR) but thermal and outgassing data have been used in a few cases. InSAR data have helped to determine the alert level at these volcanoes, served as an independent check on ground sensors, guided the deployment of ground instruments, and aided situational awareness. We will describe several lessons learned about the type of data products and information that are most needed by the volcano observatories in different countries.

  12. Early Fermi Gamma-ray Space Telescope Observations of the Quasar 3C454.3

    Energy Technology Data Exchange (ETDEWEB)

    Abdo, A

    2009-05-07

    This is the first report of Fermi Gamma-ray Space Telescope observations of the quasar 3C 454.3, which has been undergoing pronounced long-term outbursts since 2000. The data from the Large Area Telescope (LAT), covering 2008 July 7-October 6, indicate strong, highly variable {gamma}-ray emission with an average flux of {approx} 3 x 10{sup -6} photons cm{sup -2} s{sup -1}, for energies > 100 MeV. The {gamma}-ray flux is variable, with strong, distinct, symmetrically-shaped flares for which the flux increases by a factor of several on a time scale of about three days. This variability indicates a compact emission region, and the requirement that the source is optically thin to pair-production implies relativistic beaming with Doppler factor {delta} > 8, consistent with the values inferred from VLBI observations of superluminal expansion ({delta} {approx} 25). The observed {gamma}-ray spectrum is not consistent with a simple power-law, but instead steepens strongly above {approx} 2 GeV, and is well described by a broken power-law with photon indices of {approx} 2.3 and {approx} 3.5 below and above the break, respectively. This is the first direct observation of a break in the spectrum of a high luminosity blazar above 100 MeV, and it is likely direct evidence for an intrinsic break in the energy distribution of the radiating particles. Alternatively, the spectral softening above 2GeV could be due to -ray absorption via photonphoton pair production on the soft X-ray photon field of the host AGN, but such an interpretation would require the dissipation region to be located very close ({approx}< 100 gravitational radii) to the black hole, which would be inconsistent with the X-ray spectrum of the source.

  13. Photometric Repeatability of Scanned Imagery: UVIS

    Science.gov (United States)

    Shanahan, Clare E.; McCullough, Peter; Baggett, Sylvia

    2017-08-01

    We provide the preliminary results of a study on the photometric repeatability of spatial scans of bright, isolated white dwarf stars with the UVIS channel of the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST). We analyze straight-line scans from the first pair of identical orbits of HST program 14878 to assess if sub 0.1% repeatability can be attained with WFC3/UVIS. This study is motivated by the desire to achieve better signal-to-noise in the UVIS contamination and stability monitor, in which observations of standard stars in staring mode have been taken from the installation of WFC3 in 2009 to the present to assess temporal photometric stability. Higher signal to noise in this program would greatly benefit the sensitivity to detect contamination, and to better characterize the observed small throughput drifts over time. We find excellent repeatability between identical visits of program 14878, with sub 0.1% repeatability achieved in most filters. These! results support the initiative to transition the staring mode UVIS contamination and photometric stability monitor from staring mode images to spatial scans.

  14. Morphology and time variation of the Jovian Far UV aurora: Hubble Space Telescope observations

    Science.gov (United States)

    Gerard, Jean-Claude; Dols, Vincent; Paresce, Francesco; Prange, Renee

    1993-01-01

    High spatial resolution images of the north polar region of Jupiter have been obtained with the Faint Object Camera (FOC) on board the Hubble Space Telescope (HST). The first set of two images collected 87 min apart in February 1992 shows a bright (approximately or equal to 180 kR) emission superimposed on the background in rotation with the planet. Both Ly alpha images show common regions of enhanced emission but differences are also observed, possibly due to temporal variations. The second group of images obtained on June 23 and 26, 1992 isolates a spectral region near 153 nm dominated by the H2 Lyman bands and continuum. Both pictures exhibit a narrow arc structure fitting the L = 30 magnetotail field line footprint in the morning sector and a broader diffuse aurora in the afternoon. They show no indication of an evening twilight enhancement. Although the central meridian longitudes were similar, significant differences are seen in the two exposures, especially in the region of diffuse emission, and interpreted as signatures of temporal variations. The total power radiated in the H2 bands is approximately or equal to 2 x 10(exp 12) W, in agreement with previous UV spectrometer observations. The high local H2 emission rates (approximately 450 kR) imply a particle precipitation carrying an energy flux of about 5 x 10(exp -2) W/sq m.

  15. Hand gesture recognition in confined spaces with partial observability and occultation constraints

    Science.gov (United States)

    Shirkhodaie, Amir; Chan, Alex; Hu, Shuowen

    2016-05-01

    Human activity detection and recognition capabilities have broad applications for military and homeland security. These tasks are very complicated, however, especially when multiple persons are performing concurrent activities in confined spaces that impose significant obstruction, occultation, and observability uncertainty. In this paper, our primary contribution is to present a dedicated taxonomy and kinematic ontology that are developed for in-vehicle group human activities (IVGA). Secondly, we describe a set of hand-observable patterns that represents certain IVGA examples. Thirdly, we propose two classifiers for hand gesture recognition and compare their performance individually and jointly. Finally, we present a variant of Hidden Markov Model for Bayesian tracking, recognition, and annotation of hand motions, which enables spatiotemporal inference to human group activity perception and understanding. To validate our approach, synthetic (graphical data from virtual environment) and real physical environment video imagery are employed to verify the performance of these hand gesture classifiers, while measuring their efficiency and effectiveness based on the proposed Hidden Markov Model for tracking and interpreting dynamic spatiotemporal IVGA scenarios.

  16. Hubble Space Telescope observations of comet P/Shoemaker-Levy 9 (1993e)

    Science.gov (United States)

    Weaver, H.A.; Feldman, P.D.; A'Hearn, M.F.; Arpigny, C.; Brown, R.A.; Helin, E.F.; Levy, D.H.; Marsden, B.G.; Meech, K.J.; Larson, S.M.; Noll, K.S.; Scotti, J.V.; Sekanina, Z.; Shoemaker, C.S.; Shoemaker, E.M.; Smith, T.E.; Storrs, A.D.; Yeomans, D.K.; Zellner, B.

    1994-01-01

    The Hubble Space Telescope observed the fragmented comet P/Shoemaker-Levy 9 (1993e) (P indicates that it is a periodic comet) on 1 July 1993. Approximately 20 individual nuclei and their comae were observed in images taken with the Planetary Camera. After subtraction of the comae light, the 11 brightest nuclei have magnitudes between ~23.7 and 24.8. Assuming that the geometric albedo is 0.04, these magnitudes imply that the nuclear diameters are in the range ~2.5 to 4.3 kilometers. If the density of each nucleus is 1 gram per cubic centimeter, the total energy deposited by the impact of these 11 nuclei into Jupiter's atmosphere next July will be ~4 x 1030 ergs (~108 megatons of TNT). This latter number should be regarded as an upper limit because the nuclear magnitudes probably contain a small residual coma contribution. The Faint Object Spectrograph was used to search for fluorescence from OH, which is usually an excellent indicator of cometary activity. No OH emission was detected, and this can be translated into an upper limit on the water production rate of ~2 x 1027 molecules per second.

  17. Relative-locality distant observers and the phenomenology of momentum-space geometry

    Science.gov (United States)

    Amelino-Camelia, Giovanni; Arzano, Michele; Kowalski-Glikman, Jerzy; Rosati, Giacomo; Trevisan, Gabriele

    2012-04-01

    We study the translational invariance of the relative-locality framework proposed in Amelino-Camelia et al (2011 Phys. Rev. D 84 084010), which had been previously established only for the case of a single interaction. We provide an explicit example of boundary conditions at endpoints of worldlines, which indeed ensures the desired translational invariance for processes involving several interactions, even when some of the interactions are causally connected (particle exchange). We illustrate the properties of the associated relativistic description of distant observers within the example of a κ-Poincaré-inspired momentum-space geometry, with de Sitter metric and parallel transport governed by a non-metric and torsionful connection. We find that in such a theory, simultaneously emitted massless particles do not reach simultaneously a distant detector, as expected in light of the findings of Freidel and Smolin (2011 arXiv:1103.5626) on the implications of non-metric connections. We also show that the theory admits a free-particle limit, where the relative-locality results of Amelino-Camelia et al (2011 Phys. Lett. B 700 150) are reproduced. We establish that the torsion of the κ-Poincaré connection introduces a small (but observably large) dependence of the time of detection, for simultaneously emitted particles, on some properties of the interactions producing the particles at the source.

  18. Hubble Space Telescope observations of cool white dwarf stars: Detection of new species of heavy elements

    Science.gov (United States)

    Shipman, Harry; Barnhill, Maurice; Provencal, Judi; Roby, Scott; Bues, Irmela; Cordova, France; Hammond, Gordon; Hintzen, Paul; Koester, Detlev; Liebert, James

    1995-01-01

    Observations of cool white dwarf stars with the Hubble Space Telescope (HST) has uncovered a number of spectral features from previouslly unobserved species. In this paper we present the data on four cool white dwarfs. We present identifications, equivalent width measurements, and brief summaries of the significance of our findings. The four stars observed are GD 40 (DBZ3, G 74-7 (DAZ), L 745-46A (DZ), and LDS 749B (DBA). Many additional species of heavey elements were detected in GD 40 and G 74-7. In L 745-46A, while the detections are limited to Fe 1, Fe II, and Mg II, the quality of the Mg II h and K line profiles should permit a test of the line broadening theories, which are so crucial to abundance determinations. The clear detection of Mg II h and k in LDS 749 B should, once an abundance determination is made, provide a clear test of the hypothesis that the DBA stars are the result of accretion from the interstellar medium. This star contains no other clear features other than a tantalizing hint of C II 1335 with a P Cygni profile, and some expected He 1 lines.

  19. Space-based observations of fire NOx emission coefficients: a global biome-scale comparison

    Directory of Open Access Journals (Sweden)

    A. K. Mebust

    2013-08-01

    Full Text Available Biomass burning represents both a significant and highly variable source of NOx to the atmosphere. This variability stems from both the episodic nature of fires, and from fire conditions such as the modified combustion efficiency of the fire, the nitrogen content of the fuel and possibly other factors that have not been identified or evaluated by comparison with observations. Satellite instruments offer an opportunity to observe emissions from wildfires, providing a large suite of measurements which allow us to study mean behavior and variability on the regional scale in a statistically rigorous manner. Here we use space-based measurements of fire radiative power from the Moderate Resolution Imaging Spectroradiometer in combination with NO2 tropospheric column densities from the Ozone Monitoring Instrument to measure mean emission coefficients (ECs in g NO MJ−1 from fires for global biomes, and across a wide range of smaller-scale ecoregions, defined as spatially-distinct clusters of fires with similar fuel type. Mean ECs for all biomes fall between 0.250–0.362 g NO MJ−1, a range that is smaller than found in previous studies of biome-scale emission factors. The majority of ecoregion ECs fall within or near this range, implying that under most conditions, mean fire emissions per unit energy are similar between different regions regardless of fuel type or spatial variability. In contrast to these similarities, we find that about 24% of individual ecoregion ECs deviate significantly (p x emissions.

  20. Observations of V592 Cassiopeiae with the Spitzer Space Telescope - Dust in the Mid-Infrared

    CERN Document Server

    Hoard, D W; Wachter, Stefanie; Howell, Steve B; Brinkworth, Carolyn S; Ciardi, David R; Szkody, Paula; Belle, Kunegunda; Froning, Cynthia; van Belle, Gerard

    2008-01-01

    We present the ultraviolet-optical-infrared spectral energy distribution of the low inclination novalike cataclysmic variable V592 Cassiopeiae, including new mid-infrared observations from 3.5-24 microns obtained with the Spitzer Space Telescope. At wavelengths shortward of 8 microns, the spectral energy distribution of V592 Cas is dominated by the steady state accretion disk, but there is flux density in excess of the summed stellar components and accretion disk at longer wavelengths. Reproducing the observed spectral energy distribution from ultraviolet to mid-infrared wavelengths can be accomplished by including a circumbinary disk composed of cool dust, with a maximum inner edge temperature of ~500 K. The total mass of circumbinary dust in V592 Cas (~10^21 g) is similar to that found from recent studies of infrared excess in magnetic CVs, and is too small to have a significant effect on the long-term secular evolution of the cataclysmic variable. The existence of circumbinary dust in V592 Cas is possibly ...

  1. Spitzer Space Telescope observations of magnetic cataclysmic variables: possibilities for the presence of dust in polars

    CERN Document Server

    Brinkworth, C S; Wachter, S; Howell, S B; Ciardi, D R; Szkody, P; Harrison, T E; van Belle, G T; Esin, A A; 10.1086/512797

    2009-01-01

    We present Spitzer Space Telescope photometry of six short-period polars, EF Eri, V347 Pav, VV Pup, V834 Cen, GG Leo, and MR Ser. We have combined the Spitzer Infrared Array Camera (3.6 -8.0 microns) data with the 2MASS J, H, K_s photometry to construct the spectral energy distributions of these systems from the near- to mid-IR (1.235 - 8 microns). We find that five out of the six polars have flux densities in the mid-IR that are substantially in excess of the values expected from the stellar components alone. We have modeled the observed SEDs with a combination of contributions from the white dwarf, secondary star, and either cyclotron emission or a cool, circumbinary dust disk to fill in the long-wavelength excess. We find that a circumbinary dust disk is the most likely cause of the 8 micron excess in all cases, but we have been unable to rule out the specific (but unlikely) case of completely optically thin cyclotron emission as the source of the observed 8 micron flux density. While both model components...

  2. A Method for Justification of the View of Observables in Quantum Mechanics and Probability Distributions in Phase Space

    CERN Document Server

    Beniaminov, E M

    2001-01-01

    There are considered some corollaries of certain hypotheses on the observation process of microphenomena. We show that an enlargement of the phase space and of its motion group and an account for the diffusion motions of microsystems in the enlarged space, the motions which act by small random translations along the enlarged group, lead to observable quantum effects. This approach enables one to recover probability distributions in the phase space for wave functions. The parameters of the model considered here are estimated on the base of Lamb's shift in the spectrum of the hydrogen's atom.

  3. Hubble Space Telescope Eclipse Observations of the Nova Like Cataclysmic Variable UX Ursae Majoris

    Science.gov (United States)

    Knigge, Christian; Long, Knox S.; Wade, Richard A.; Baptista, Raymundo; Horne, Keith; Hubeny, Ivan; Rutten, Rene G. M.

    1998-01-01

    We present and analyze Hubble Space Telescope observations of the eclipsing nova-like cataclysmic variable UX UMa obtained with the Faint Object Spectrograph. Two eclipses each were observed with the G160L grating (covering the ultraviolet waveband) in 1994 August and with the PRISM (covering the near-ultraviolet to near-infrared) in November of the same year. The system was about 50% brighter in November than in August, which, if due to a change in the accretion rate, indicates a fairly substantial increase in Mass accretion by about 50%. The eclipse light curves are qualitatively consistent with the gradual occultation of an accretion disk with a radially decreasing temperature distribution. The light curves also exhibit asymmetries about mideclipse that are likely due to a bright spot at the disk edge. Bright-spot spectra have been constructed by differencing the mean spectra observed at pre- and posteclipse orbital phases. These difference spectra contain ultraviolet absorption lines and show the Balmer jump in emission. This suggests that part of the bright spot may be optically thin in the continuum and vertically extended enough to veil the inner disk and/or the outflow from UX UMa in some spectral lines. Model disk spectra constructed as ensembles of stellar atmospheres provide poor descriptions of the observed posteclipse spectra, despite the fact that UX UMa's light should be dominated by the disk at this time. Suitably scaled single temperature model stellar atmospheres with T(sub eff) approximately equals 12,500-14,500 K actually provide a better match to both the ultraviolet and optical posteclipse spectra. Evidently, great care must be taken in attempts to derive accretion rates from comparisons of disk models to observations. One way to reconcile disk models with the observed posteclipse spectra is to postulate the presence of a significant amount of optically thin material in the system. Such an optically thin component might be associated with the

  4. Validation of stratospheric and mesospheric ozone observed by SMILES from International Space Station

    Directory of Open Access Journals (Sweden)

    Y. Kasai

    2013-09-01

    Full Text Available We observed ozone (O3 in the vertical region between 250 and 0.0005 hPa (~ 12–96 km using the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES on the Japanese Experiment Module (JEM of the International Space Station (ISS between 12 October 2009 and 21 April 2010. The new 4 K superconducting heterodyne receiver technology of SMILES allowed us to obtain a one order of magnitude better signal-to-noise ratio for the O3 line observation compared to past spaceborne microwave instruments. The non-sun-synchronous orbit of the ISS allowed us to observe O3 at various local times. We assessed the quality of the vertical profiles of O3 in the 100–0.001 hPa (~ 16–90 km region for the SMILES NICT Level 2 product version 2.1.5. The evaluation is based on four components: error analysis; internal comparisons of observations targeting three different instrumental setups for the same O3 625.371 GHz transition; internal comparisons of two different retrieval algorithms; and external comparisons for various local times with ozonesonde, satellite and balloon observations (ENVISAT/MIPAS, SCISAT/ACE-FTS, Odin/OSIRIS, Odin/SMR, Aura/MLS, TELIS. SMILES O3 data have an estimated absolute accuracy of better than 0.3 ppmv (3% with a vertical resolution of 3–4 km over the 60 to 8 hPa range. The random error for a single measurement is better than the estimated systematic error, being less than 1, 2, and 7%, in the 40–1, 80–0.1, and 100–0.004 hPa pressure regions, respectively. SMILES O3 abundance was 10–20% lower than all other satellite measurements at 8–0.1 hPa due to an error arising from uncertainties of the tangent point information and the gain calibration for the intensity of the spectrum. SMILES O3 from observation frequency Band-B had better accuracy than that from Band-A. A two month period is required to accumulate measurements covering 24 h in local time of O3 profile. However such a dataset can also contain variation due to

  5. Rapidities and Observable 3-Velocities in the Flat Finslerian Event Space with Entirely Broken 3D Isotropy

    Directory of Open Access Journals (Sweden)

    George Yu. Bogoslovsky

    2008-05-01

    Full Text Available We study the geometric phase transitions that accompany the dynamic rearrangement of vacuum under spontaneous violation of initial gauge symmetry. The rearrangement may give rise to condensates of three types, namely the scalar, axially symmetric, and entirely anisotropic condensates. The flat space-time keeps being the Minkowski space in the only case of scalar condensate. The anisotropic condensate having arisen, the respective anisotropy occurs also in space-time. In this case the space-time filled with axially symmetric condensate proves to be a flat relativistically invariant Finslerian space with partially broken 3D isotropy, while the space-time filled with entirely anisotropic condensate proves to be a flat relativistically invariant Finslerian space with entirely broken 3D isotropy. The two Finslerian space types are described briefly in the extended introduction to the work, while the original part of the latter is devoted to determining observable 3-velocities in the entirely anisotropic Finslerian event space. The main difficulties that are overcome in solving that problem arose from the nonstandard form of the light cone equation and from the necessity of correct introducing of a norm in the linear vector space of rapidities.

  6. Accretion disk reverberation with Hubble Space Telescope observations of NGC 4593

    Science.gov (United States)

    Cackett, Edward; McHardy, Ian; Horne, Keith D.; Goad, Michael; Edelson, Rick; Korista, Kirk T.; Chiang, Chia-Ying

    2017-08-01

    Irradiation of the accretion disk by X-ray/EUV photons should lead to wavelength-dependent UV/optical continuum time lags as the hotter, inner parts of the disk will see the variable irradiating flux before the cooler, outer parts of the disk. Recently, there has been a significant improvement in wavelength-dependent lag measurements from high-cadence monitoring and a picture is emerging that the accretion disk sizes are a factor of 2 - 3 larger than predicted by the standard disk model. We obtained Hubble Space Telescope spectroscopy of NGC 4593 as part of a larger multi-wavelength reverberation mapping campaign including monitoring by Swift and Kepler. From 2016 July 12 to 2016 August 6 we performed 26 observations with an approximately daily cadence using the Space Telescope Imaging Spectrograph. The spectra cover a nearly continuous wavelength range from approximately 1150 - 10000Å. The continuum is significantly variable at all wavelengths, with variations at 1150Å leading variations at 8950Å by approximately 1.2 days. In the scenario where X-rays or EUV photons drive variability in the accretion disk the time lags should follow λ4/3. Here, we see a significant deviation from this around the Balmer jump, indicating a large contribution to the lags from diffuse continuum emission in the broad line region. However, even when taking this diffuse continuum lag into account, we still find that the accretion disk lags are a factor of about 3 larger than expected from the standard disk model.

  7. United Kingdom Infrared Telescope's Spectrograph Observations of Human-Made Space Objects

    Science.gov (United States)

    Buckalew, Brent; Abercromby, Kira; Lederer, Susan; Frith, James; Cowardin, Heather

    2017-01-01

    Presented here are the results of the United Kingdom Infrared Telescope (UKIRT) spectral observations of human-made space objects taken from 2014 to 2015. The data collected using the UIST infrared spectrograph cover the wavelength range 0.7-2.5 micrometers. Overall, data were collected on 18 different orbiting objects at or near the geosynchronous (GEO) regime. Thirteen of the objects are spacecraft, one is a rocket body, and four are cataloged as debris pieces. The remotely collected data are compared to the laboratory-collected reflectance data on typical spacecraft materials; thereby general materials are identified but not specific types. These results highlight the usefulness of observations in the infrared by focusing on features from hydrocarbons and silicon. The spacecraft show distinct features due to the presence of solar panels. Signature variations between rocket bodies, due to the presence of various metals and paints on their surfaces, show a clear distinction from those objects with solar panels, demonstrating that one can distinguish most spacecraft from rocket bodies through infrared spectrum analysis. Finally, the debris pieces tend to show featureless, dark spectra. These results show that the laboratory data in its current state give excellent indications as to the nature of the surface materials on the objects. Further telescopic data collection and model updates to include more materials, noise, surface roughness, and material degradation are necessary to make better assessments of orbital object material types. A comparison conducted between objects observed previously with the NASA Infrared Telescope Facility (IRTF) shows similar materials and trends from the two telescopes and from the two distinct data sets. However, based on the current state of the model, infrared spectroscopic data are adequate to classify objects in GEO as spacecraft, rocket bodies, or debris.

  8. United Kingdom Infrared Telescope's Spectrograph Observations of Human-Made Space Objects

    Science.gov (United States)

    Buckalew, Brent; Abercromby, Kira; Lederer, Susan; Cowardin, Heather; Frith, James

    2017-01-01

    Presented here are the results of the United Kingdom Infrared Telescope (UKIRT) spectral observations of human-made space objects taken from 2014 to 2015. The data collected using the UKIRT 1-5 micron Imager Spectrometer (UIST) cover the wavelength range 0.7-2.5 micrometers. Overall, data were collected on 18 different orbiting objects at or near geosynchronous orbit (GEO). Two of the objects are controlled spacecraft, twelve are non-controlled spacecraft, one is a rocket body, and three are cataloged as debris. The remotely collected data are compared to the laboratory-collected reflectance data on typical spacecraft materials; thereby general materials are identified but not specific types. These results highlight the usefulness of observations in the infrared by focusing on features from hydrocarbons and silicon. The spacecraft, both the controlled and non-controlled, show distinct features due to the presence of solar panels whereas the rocket bodies do not. Signature variations between rocket bodies, due to the presence of various metals and paints on their surfaces, show a clear distinction from those objects with solar panels, demonstrating that one can distinguish most spacecraft from rocket bodies through infrared spectrum analysis. Finally, the debris pieces tend to show featureless, dark spectra. These results show that the laboratory data in its current state give well-correlated indications as to the nature of the surface materials on the objects. Further telescopic data collection and model updates to include noise, surface roughness, and material degradation are necessary to make better assessments of orbital object material types. A comparison conducted between objects observed previously with the NASA Infrared Telescope Facility (IRTF) shows similar materials and trends from the two telescopes and different times. However, based on the current state of the model, infrared spectroscopic data are adequate to classify objects in GEO as spacecraft

  9. Infrared Telescope Facility's Spectrograph Observations of Human-Made Space Objects

    Science.gov (United States)

    Abercromby, K.; Buckalew, B.; Abell, P.; Cowardin, H.

    2015-01-01

    Presented here are the results of the Infrared Telescope Facility (IRTF) spectral observations of human-made space objects taken from 2006 to 2008. The data collected using the SpeX infrared spectrograph cover the wavelength range 0.7-2.5 micrometers. Overall, data were collected on 20 different orbiting objects at or near the geosynchronous (GEO) regime. Four of the objects were controlled spacecraft, seven were non-controlled spacecraft, five were rocket bodies, and the final four were cataloged as debris pieces. The remotely collected data are compared to the laboratory-collected reflectance data on typical spacecraft materials, thereby general materials are identified but not specific types. These results highlight the usefulness of observations in the infrared by focusing on features from hydrocarbons, silicon, and thermal emission. The spacecraft, both the controlled and non-controlled, show distinct features due to the presence of solar panels, whereas the rocket bodies do not. Signature variations between rocket bodies, due to the presence of various metals and paints on their surfaces, show a clear distinction from those objects with solar panels, demonstrating that one can distinguish most spacecraft from rocket bodies through infrared spectrum analysis. Finally, the debris pieces tend to show featureless, dark spectra. These results show that the laboratory data in its current state give excellent indications as to the nature of the surface materials on the objects. Further telescopic data collection and model updates to include noise, surface roughness, and material degradation are necessary to make better assessments of orbital object material types. However, based on the current state of the comparison between the observations and the laboratory data, infrared spectroscopic data are adequate to classify objects in GEO as spacecraft, rocket bodies, or debris.

  10. 3. Observing the Arctic from space: educational opportunities for an International Polar Year

    Science.gov (United States)

    Kelley, J.; Yanow, G.; Alexander, V.; Johnson, L.

    2003-04-01

    Recommendations for an International Polar Year (IPY) will require integrated circumpolar research projects using present and advanced technologies. The IPY will offer exceptional opportunities for participation by indigenous residents of the Arctic. Educational outreach will be an essential component of IPY programs, to improve science competence and citizen awareness through participation in IPY projects and utilization of educational products. An important and practical objective of IPY educational outreach is to recognize that the earth is a system and that it is best from space that we can acquire seasonal and secular atmospheric, terrestrial and oceanic environmental data. Acquisition of reliable ground truth data in support of remote sensing of geophysical and geochemical variables will be essential, especially with broad long-term coverage in the polar regions. It should be an essential element of the IPY program. In the United States NASA has developed a strategy for long-term monitoring of some key parameters needed to bring us closer to the answers we need regarding climate change in the Arctic and polar regions. Technology consists of a group of five polar satellites that make a suite of earth observations referred to as the "A-Train". Data from this group of satellites, as well as from the Orbital Carbon Observatory (OCO) and older Quikscat and new Seawinds radar missions, will provide focus for an education program based not only on the acquisition of polar data but also on how these data correlate with global observations. We recommend that an educational outreach secretariat be developed for each national program that will involve the indigenous people of the Arctic and elsewhere in acquisition of data relevant to satellite observations. The secretariat will provide for information transfer, coordination with scientific projects, opportunities for participation in project activities, communication of scientific results to the public, and greater

  11. Observing the Arctic From Space: Educational Opportunities for an International Polar Year

    Science.gov (United States)

    Kelley, J. J.; Yanow, G.; Alexander, V.; Johnson, L.

    2003-12-01

    Recommendations for an International Polar Year (IPY) will require integrated circumpolar research projects using present and advanced technologies. The IPY will offer exceptional opportunities for participation by indigenous residents of the Arctic. Educational outreach will be an essential component of IPY programs, to improve science competence and citizen awareness through participation in IPY projects and utilization of educational products. An important and practical objective of IPY educational outreach is to recognize that the earth is a system and that it is best from space that we can acquire seasonal and secular atmospheric, terrestrial and oceanic environmental data. Acquisition of reliable ground truth data in support of remote sensing of geophysical and geochemical variables will be essential, especially with broad long-term coverage in the polar regions. It should be an essential element of the IPY program. In the United States NASA has developed a strategy for long-term monitoring of some key parameters needed to bring us closer to the answers we need regarding climate change in the Arctic and polar regions. Technology consists of a group of five polar satellites that make a suite of earth observations referred to as the "A-Train". Data from this group of satellites, as well as from the Orbital Carbon Observatory (OCO) and older Quikscat and new Seawinds radar missions, will provide focus for an education program based not only on the acquisition of polar data but also on how these data correlate with global observations. We recommend that an educational outreach secretariat be developed for each national program that will involve the indigenous people of the Arctic and elsewhere in acquisition of data relevant to satellite observations. The secretariat will provide for information transfer, coordination with scientific projects, opportunities for participation in project activities, communication of scientific results to the public, and greater

  12. Regional nitrogen oxides emission trends in East Asia observed from space

    Directory of Open Access Journals (Sweden)

    B. Mijling

    2013-07-01

    Full Text Available Due to changing economic activity, emissions of air pollutants in East Asia change rapidly in space and time. Monthly emission estimates of nitrogen oxides derived from satellite observations provide valuable insight in the evolution of anthropogenic activity on a regional scale. We present the first results of a new emission estimation algorithm, specifically designed to use daily satellite observations of column concentrations for fast updates of emissions of short-lived atmospheric constituents on a~mesoscopic scale (~ 0.25° × 0.25°. The algorithm is used to construct a monthly NOx emission time series for 2007–2011 from tropospheric NO2 observations of GOME-2 for East Chinese provinces and surrounding countries. The new emission estimates correspond well with the bottom-up inventory of EDGAR v4.2, but are smaller than the inventories of INTEX-B and MEIC. They reveal a strong positive trend during 2007–2011 for almost all Chinese provinces, related to the country's economic development. We find a 41% increment of NOx emissions in East China during this period, which shows the need to update emission inventories in this region on a regular basis. Negative emission trends are found in Japan and South Korea, which can be attributed to a combined effect of local environmental policy and global economic crises. Analysis of seasonal variation distinguishes between regions with dominant anthropogenic or biogenic emissions. For regions with a mixed anthropogenic and biogenic signature, the opposite seasonality can be used for an estimation of the separate emission contributions. Finally, the non-local concentration/emission relationships calculated by the algorithm are used to quantify the direct effect of regional NOx emissions on tropospheric NO2 concentrations outside the region. For regions such as North Korea and Beijing province, a substantial part of the tropospheric NO2 originates from emissions elsewhere.

  13. Regional nitrogen oxides emission trends in East Asia observed from space

    Science.gov (United States)

    Mijling, B.; van der A, R. J.; Zhang, Q.

    2013-12-01

    Due to changing economic activity, emissions of air pollutants in East Asia are changing rapidly in space and time. Monthly emission estimates of nitrogen oxides derived from satellite observations provide valuable insight into the evolution of anthropogenic activity on a regional scale. We present the first results of a new emission estimation algorithm, specifically designed to use daily satellite observations of column concentrations for fast updates of emissions of short-lived atmospheric constituents on a mesoscopic scale (~ 0.25° × 0.25°). The algorithm is used to construct a monthly NOx emission time series for the period 2007-2011 from tropospheric NO2 observations of GOME-2 for East Chinese provinces and surrounding countries. The new emission estimates correspond well with the bottom-up inventory of EDGAR v4.2, but are smaller than the inventories of INTEX-B and MEIC. They reveal a strong positive trend during 2007-2011 for almost all Chinese provinces, related to the country's economic development. We find a 41% increment of NOx emissions in East China during this period, which shows the need to update emission inventories in this region on a regular basis. Negative emission trends are found in Japan and South Korea, which can be attributed to a combined effect of local environmental policy and global economic crises. Analysis of seasonal variation distinguishes between regions with dominant anthropogenic or biogenic emissions. For regions with a mixed anthropogenic and biogenic signature, the opposite seasonality can be used for an estimation of the separate emission contributions. Finally, the non-local concentration/emission relationships calculated by the algorithm are used to quantify the direct effect of regional NOx emissions on tropospheric NO2 concentrations outside the region. For regions such as North Korea and the Beijing municipality, a substantial part of the tropospheric NO2 originates from emissions elsewhere.

  14. Validation of stratospheric and mesospheric ozone observed by SMILES from International Space Station

    Directory of Open Access Journals (Sweden)

    Y. Kasai

    2013-03-01

    Full Text Available We observed the diurnal variation of ozone (O3 in the vertical region between 250 and 0.0005 hPa (~12–96 km using the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES on the Japanese Experiment Module (JEM of the International Space Station (ISS between 12 October 2009 and 21 April 2010. The new 4 K superconducting heterodyne receiver technology of SMILES allowed us to obtain a one order of magnitude better signal-to-noise ratio for the O3 line observation compared to past spaceborne microwave instruments. We assessed the quality of the vertical profiles of O3 in the 100–0.001 hP (~16–90 km region for the SMILES NICT Level 2 product version 2.1.5. The evaluation is based on four components; error analysis; internal comparisons of observations targeting three different instrumental setups for the same O3 625.371 GHz transition; internal comparisons of two different retrieval algorithms; and external comparisons for various local times with ozonesonde, satellite and balloon observations (ENVISAT/MIPAS, SCISAT/ACE-FTS, Odin/OSIRIS, Odin/SMR, Aura/MLS, TELIS. SMILES O3 data have an estimated absolute accuracy of better than 0.3 ppmv (3% with a vertical resolution of 3–4 km over the 60 to 8 hPa range. The random error for a single measurement is better than the estimated systematic error, being less than 1, 2, and 7%, in the 40–1, 80–0.1, and 100–0.004 hPa pressure region, respectively. SMILES O3 abundance was 10–20% lower than all other satellite measurements at 8–0.1 hPa due to an error arising from uncertainties of the tangent point information and the calibration problem for the intensity of the spectrum. The non sun-synchronous orbit of the ISS allowed us to observe O3 at various local times. A two month period is required to accumulate measurements covering 24 h in local time. However such a dataset can also contain variation due to dynamical, seasonal, and latitudinal effects.

  15. Verification of Atmospheric Signals Associated with Major Seismicity by Space and Terrestrial Observations

    Science.gov (United States)

    Ouzounov, D.; Pulinets, S.; Taylor, P.; Bryant, N.; Cervone, G.; Kafatos, M.; Habib, S.

    2008-12-01

    Observations from the last twenty years suggest the existence of electromagnetic (EM) phenomena during or preceding some earthquakes [Hayakawa et al, 2004; Pulinets at al, 1999,2004, 2006, Ouzounov et al, 2007 and Liu et al, 2004]. Both our previous studies [Pulinets at al, 2005, 2006, Ouzounov et al, 2006, 2007] and the latest review by the Earthquake Remote Precursor Sensing panel [ERPS; 2003-2005]; have shown that there were precursory atmospheric TIR signals observed on the ground and in space associated with several recent earthquakes. [Tramutoli et al, 2005, 2006, Cervone et al, 2006, Ouzounov et al, 2004,2006]. To study these signals, we applied both multi parameter statistical analysis and data mining methods that require systematic measurements from an Integrated Sensor Web of observations of several physical and environmental parameters. These include long wave earth infra-red radiation, ionospheric electrical and magnetic parameters, temperature and humidity of the boundary layer, seismicity and may be associated with major earthquakes. Our goal is to verify the earthquake atmospheric correlation in two cases: (i) backward analysis - 2000-2008 hindcast monitoring of multi atmospheric parameters over the Kamchatka region, Russia ; and (ii) forward real-time alert analysis over different seismo-tectonic regions for California, Turkey, Taiwan and Japan. Our latest results, from several post-earthquake independent analyses of more then 100 major earthquakes, show that joint satellite and some ground measurements, using an integrated web, could provide a capability for observing pre-earthquake atmospheric signals by combining the information from multiple sensors into a common framework. Using our methodology, we evaluated and compared the observed signals preceding the latest M7.9 Sichuan earthquake (05/12/2008), M8.0 earthquake in Peru (08/15/2007), M7.6 Kashmir earthquake (10/08/2005) and M9.0 Sumatra earthquake (12/26/2004). We found evidence of the

  16. Earth Observation from the International Space Station -Remote Sensing in Schools-

    Science.gov (United States)

    Schultz, Johannes; Rienow, Andreas; Graw, Valerie; Heinemann, Sascha; Selg, Fabian; Menz, Gunter

    2016-04-01

    Since spring 2014, the NASA High Definition Earth Viewing (HDEV) mission at the International Space Station (ISS) is online. HDEV consists of four cameras mounted at ESA's Columbus laboratory and is recording the earth 24/7. The educational project 'Columbus Eye - Live-Imagery from the ISS in Schools' has published a learning portal for earth observation from the ISS (www.columbuseye.uni-bonn.de). Besides a video live stream, the portal contains an archive providing spectacular footage, web-GIS and an observatory with interactive materials for school lessons. Columbus Eye is carried out by the University of Bonn and funded by the German Aerospace Center (DLR) Space Administration. Pupils should be motivated to work with the footage in order to learn about patterns and processes of the coupled human-environment system like volcano eruptions or deforestation. The material is developed on the experiences of the FIS (German abbreviation for "Remote Sensing in Schools") project and its learning portal (http://www.fis.uni-bonn.de). Based on the ISS videos three different teaching material types are developed. The simplest teaching type are provided by worksheets, which have a low degree of interactivity. Alongside a short didactical commentary for teachers is included. Additionally, videos, ancillary information, maps, and instructions for interactive school experiments are provided. The observatory contains the second type of the Columbus Eye teaching materials. It requires a high degree of self-organisation and responsibility of the pupils. Thus, the observatory provides the opportunity for pupils to freely construct their own hypotheses based on a spatial analysis tool similar to those provided by commercial software. The third type are comprehensive learning and teaching modules with a high degree of interactivity, including background information, interactive animations, quizzes and different analysis tools (e.g. change detection, classification, polygon or NDVI

  17. Space Telescope and Optical Reverberation Mapping Project.I. Ultraviolet Observations of the Seyfert 1 Galaxy NGC 5548 with the Cosmic Origins Spectrograph on Hubble Space Telescope

    NARCIS (Netherlands)

    De Rosa, G.; Peterson, B.M.; Ely, J.; Kriss, G.A.; Crenshaw, D.M.; Horne, K.; Korista, K.T.; Netzer, H.; Pogge, R.W.; Arévalo, P.; Barth, A.J.; Bentz, M.C.; Brandt, W.N.; Breeveld, A.A.; Brewer, B.J.; Dalla Bontà, E.; De Lorenzo-Cáceres, A.; Denney, K.D.; Dietrich, M.; Edelson, R.; Evans, P.A.; Fausnaugh, M.M.; Gehrels, N.; Gelbord, J.M.; Goad, M.R.; Grier, C.J.; Grupe, D.; Hall, P.B.; Kaastra, J.; Kelly, B.C.; Kennea, J.A.; Kochanek, C.S.; Lira, P.; Mathur, S.; McHardy, I.M.; Nousek, J.A.; Pancoast, A.; Papadakis, I.; Pei, L.; Schimoia, J.S.; Siegel, M.; Starkey, D.; Treu, T.; Uttley, P.; Vaughan, S.; Vestergaard, M.; Villforth, C.; Yan, H.; Young, S.; Zu, Y.

    2015-01-01

    We describe the first results from a six-month long reverberation-mapping experiment in the ultraviolet based on 171 observations of the Seyfert 1 galaxy NGC 5548 with the Cosmic Origins Spectrograph on the Hubble Space Telescope. Significant correlated variability is found in the continuum and

  18. Dependency of resolvable gravitational spatial resolution on space-borne observation techniques

    NARCIS (Netherlands)

    Visser, P.N.A.M.; Schrama, E.J.O.; Sneeuw, N.; Weigelt, M.

    2009-01-01

    The so-called Colombo-Nyquist (Colombo, The global mapping of gravity with two satellites, 1984) rule in satellite geodesy has been revisited. This rule predicts that for a gravimetric satellite flying in a (near-)polar circular repeat orbit, the maximum resolvable geopotential spherical harmonic de

  19. Dependency of resolvable gravitational spatial resolution on space-borne observation techniques

    NARCIS (Netherlands)

    Visser, P.N.A.M.; Schrama, E.J.O.; Sneeuw, N.; Weigelt, M.

    2009-01-01

    The so-called Colombo-Nyquist (Colombo, The global mapping of gravity with two satellites, 1984) rule in satellite geodesy has been revisited. This rule predicts that for a gravimetric satellite flying in a (near-)polar circular repeat orbit, the maximum resolvable geopotential spherical harmonic

  20. Statistical Track-Before-Detect Methods Applied to Faint Optical Observations of Resident Space Objects

    Science.gov (United States)

    Fujimoto, K.; Yanagisawa, T.; Uetsuhara, M.

    arcs in space surveillance are often both short and sparse. FISST methodologies have been applied to the general problem of SSA by many authors, but they generally focus on tracking scenarios with long arcs or assume that line detection is tractable. We will instead focus this work on estimating sensor-level kinematics of RSOs for low SNR too-short arc observations. Once said estimate is made available, track association and simultaneous initial orbit determination may be achieved via any number of proposed solutions to the too-short arc problem, such as those incorporating the admissible region. We show that the benefit of combining FISST-based TBD with too-short arc association goes both ways; i.e., the former provides consistent statistics regarding bearing-only measurements, whereas the latter makes better use of the precise dynamical models nominally applicable to RSOs in orbit determination.

  1. The origin of long-period lattice spacings observed in iron-carbide nanowires encapsulated by multiwall carbon nanotubes.

    Science.gov (United States)

    Boi, Filippo S; Mountjoy, Gavin; Luklinska, Zofia; Spillane, Liam; Karlsson, Lisa S; Wilson, Rory M; Corrias, Anna; Baxendale, Mark

    2013-10-01

    Structures comprising single-crystal, iron-carbon-based nanowires encapsulated by multiwall carbon nanotubes self-organize on inert substrates exposed to the products of ferrocene pyrolysis at high temperature. The most commonly observed encapsulated phases are Fe₃C, α-Fe, and γ-Fe. The observation of anomalously long-period lattice spacings in these nanowires has caused confusion since reflections from lattice spacings of ≥ 0.4 nm are kinematically forbidden for Fe₃C, most of the rarely observed, less stable carbides, α-Fe, and g-Fe. Through high-resolution electron microscopy, selective area electron diffraction, and electron energy loss spectroscopy we demonstrate that the observed long-period lattice spacings of 0.49, 0.66, and 0.44 nm correspond to reflections from the (100), (010), and (001) planes of orthorhombic Fe₃C (space group Pnma). Observation of these forbidden reflections results from dynamic scattering of the incident beam as first observed in bulk Fe₃C crystals.With small amounts of beam tilt these reflections can have significant intensities for crystals containing glide planes such as Fe₃C with space groups Pnma or Pbmn.

  2. HUBBLE SPACE TELESCOPE Observations of the Host Galaxy of GRB 970508

    Science.gov (United States)

    Fruchter, A. S.; Pian, E.; Gibbons, R.; Thorsett, S. E.; Ferguson, H.; Petro, L.; Sahu, K. C.; Livio, M.; Caraveo, P.; Frontera, F.; Kouveliotou, C.; Macchetto, D.; Palazzi, E.; Pedersen, H.; Tavani, M.; van Paradijs, J.

    2000-12-01

    We report on observations of the field of GRB 970508 made in 1998 early August, 454 days after outburst, with the STIS CCD camera on board the Hubble Space Telescope (HST). The images, taken in open filter (50CCD) mode, clearly reveal the presence of a galaxy that was overwhelmed in earlier (1997 June) HST images by emission from the optical transient (OT). The galaxy is regular in shape: after correcting for the HST/STIS PSF, it is well fitted by an exponential disk with a scale length of 0.046"+/-0.006" and an ellipticity of 0.70+/-0.07. All observations are marginally consistent with a continuous decline in OT emission as t-1.3 beginning 2 days after outburst; however, we find no direct evidence in the late-time HST image for emission from the OT, and the surface brightness profile of the galaxy is most regular if we assume that the OT emission is negligible, suggesting that the OT may have faded more rapidly at late times than is predicted by the power-law decay. Due to the wide bandwidth of the STIS clear mode, the estimated magnitude of the galaxy is dependent on the galaxy spectrum that is assumed. Using colors obtained from late-time ground-based observations to constrain the spectrum, we find V=25.4+/-0.15, a few tenths of a magnitude brighter than earlier ground-based estimates that were obtained by observing the total light of the galaxy and the OT and then subtracting the estimated OT brightness, assuming that it fades as a single power law. This again suggests that the OT may have faded faster at late time than the power law predicts. The position of the OT agrees with that of the isophotal center of the galaxy to 0.01", which, at the galaxy redshift z=0.83, corresponds to an offset from the center of the host of <~70 pc. This remarkable agreement raises the possibility that the gamma-ray burst may have been associated with either an active galactic nucleus or a nuclear starburst.

  3. A Framework for Orbital Performance Evaluation in Distributed Space Missions for Earth Observation

    Science.gov (United States)

    Nag, Sreeja; LeMoigne-Stewart, Jacqueline; Miller, David W.; de Weck, Olivier

    2015-01-01

    Distributed Space Missions (DSMs) are gaining momentum in their application to earth science missions owing to their unique ability to increase observation sampling in spatial, spectral and temporal dimensions simultaneously. DSM architectures have a large number of design variables and since they are expected to increase mission flexibility, scalability, evolvability and robustness, their design is a complex problem with many variables and objectives affecting performance. There are very few open-access tools available to explore the tradespace of variables which allow performance assessment and are easy to plug into science goals, and therefore select the most optimal design. This paper presents a software tool developed on the MATLAB engine interfacing with STK, for DSM orbit design and selection. It is capable of generating thousands of homogeneous constellation or formation flight architectures based on pre-defined design variable ranges and sizing those architectures in terms of predefined performance metrics. The metrics can be input into observing system simulation experiments, as available from the science teams, allowing dynamic coupling of science and engineering designs. Design variables include but are not restricted to constellation type, formation flight type, FOV of instrument, altitude and inclination of chief orbits, differential orbital elements, leader satellites, latitudes or regions of interest, planes and satellite numbers. Intermediate performance metrics include angular coverage, number of accesses, revisit coverage, access deterioration over time at every point of the Earth's grid. The orbit design process can be streamlined and variables more bounded along the way, owing to the availability of low fidelity and low complexity models such as corrected HCW equations up to high precision STK models with J2 and drag. The tool can thus help any scientist or program manager select pre-Phase A, Pareto optimal DSM designs for a variety of science

  4. Consistency in long-term observations of oceans and ice from space

    Science.gov (United States)

    Zabel, I. H. H.; Jezek, K. C.

    1994-01-01

    Satellite remote sensing has provided powerful tools for constructing long-term records of observations of many of Earth's geophysical processes. Geophysicists studying climage change would like to construct time series of data which are as long, accurate, and consistent as possible. While technological advances continue to improve the quality of observations from space, they also present consistency problems. The scanning multichannel microwave radiometer (SMMR), which operated from October 1978 to August 1987, and the special sensor microwave imager (SSMI), which overlapped with the SMMR for nearly two months in 1987, have provided microwave radiances which have been used to monitor long-term changes in sea ice concentration and snow accumulation, among other things. Inspection has shown, however, that brightness temperatures from the two sensors over the same polar firn-covered scene can differ by as much as 14 K. Calibration corrections for polar firn have been derived; in this paper, we present calculations addressing the physics of the small frequency and viewing angle differences between the SMMR and the SSMI on microwave emission from polar scenes containing free water. We focus here only on surface emission. We use a surface scattering model and study the effects of surface roughness, snow wetness, snow density, and young sea ice concentration. We also compare data from Antarctica with our modeled results. We find that for most scenes, surface roughness dominates over the effects of frequency and viewing angle differences, but that for open long-term times series, data must be calibrated and constructed at the geophysical product level rather than at the level of measured radiances.

  5. Stellar activity as observed by the KEPLER space telescope: The K Dwarf KIC 8429280

    Science.gov (United States)

    Savanov, I. S.

    2011-09-01

    The activity of the K dwarf KIC 8429280 (TYC 3146-35-1) has been studied. Unique high-precision photometric observations of this object obtained with the KEPLER space telescope suggest a pronounced amplitude modulation of the brightness of the star, and have made possible the analysis of surface-temperature inhomogeneities. The evolution of active regions on the surface of KIC 8429280 has been traced during 105 rotation periods. Evidence has been found for the existence of two active longitudes on the surface of KIC 8429280, separated by approximately 180°. The motion of the active longitudes on the surface of KIC 8429280 is complex and unstable. At some times, the active regions moved together in longitude with the rotation of the star, while they moved in opposite directions at other time. The less active region sometimes disappeared completely, and only one active region was observed on the stellar surface. The area of the spotted surface S is 4% of the visible stellar surface for the adopted inclination of the rotation axis of the star to the line of sight, i = 60°. The periodicity for variations in S is no less than 90 d. The timescale for the change in the amplitude of the brightness variations is 30 d. Three epochs of alternation of the active longitudes are close in time to three of four firmly established minima in the amplitudes of the brightness variations. The results of the light-curve analysis for KIC 8429280 are compared to results obtained for the young active solar-type star Corot-Exo-2, which has a similar light curve with a pronounced modulation.

  6. The Extreme Ultraviolet Imagers (EUVIs): Earth-observing telescopes on International Space Station

    Science.gov (United States)

    Uji, Kentaro; Yoshikawa, Ichiro; Yoshioka, Kazuo; Murakami, Go; Yamazaki, Atsushi

    2012-11-01

    The Extreme Ultraviolet Imagers (EUVIs) were launched on 21st July 2012 as payloads to the Exposed Facility of the Japanese Experiment Module (JEM-EF) on the International Space Station. The EUVIs are parts of the IMAP (Ionosphere, Mesosphere, upper Atmosphere, and Plasmasphere mapping) mission to observe the Earth's upper atmosphere, mesosphere, ionosphere, thermosphere and plasmasphere. The other part of IMAP is a visible and near-infrared spectral imager (VISI). In this mission, we install two independent and identical telescopes. One telescope detects the terrestrial EUV emission from O+ (at the wavelength of 83.4 nm), and the other one detects He+ (30.4 nm). At the altitude of approximately 400 km, the two telescopes direct towards the Earth's limb to look at the ionosphere and plasmasphere from the inside-out. The maximum spatial resolution is 0.1° and time resolution is 1 minute. The optical instruments consist of multilayer coated mirrors which are optimized for 30.4 nm, metallic thin filters and 5-stage microchannel plates to pick up photon events efficiently. In our presentation, we report the mission overview, the instruments and the result of ground calibrations.

  7. Hubble Space Telescope observations of an extraordinary flare in the M87 jet

    CERN Document Server

    Madrid, Juan P

    2009-01-01

    HST-1, a knot along the M87 jet located 0.85 arcsec from the nucleus of the galaxy has experienced dramatic and unexpected flaring activity since early 2000. We present analysis of Hubble Space Telescope Near-Ultraviolet (NUV) imaging of the M87 jet from 1999 May to 2006 December that reveals that the NUV intensity of HST-1 has increased 90 times over its quiescent level and outshines the core of the galaxy. The NUV light curve that we derive is synchronous with the light curves derived in other wavebands. The correlation of X-ray and NUV light curves during the HST-1 flare confirms the synchrotron origin of the X-ray emission in the M87 jet. The outburst observed in HST-1 is at odds with the common definition of AGN variability usually linked to blazars and originating in close proximity of the central black hole. In fact, the M87 jet is not aligned with our line of sight and HST-1 is located at one million Schwarzchild radii from the super-massive black hole in the core of the galaxy.

  8. Relative-locality distant observers and the phenomenology of momentum-space geometry

    CERN Document Server

    Amelino-Camelia, Giovanni; Kowalski-Glikman, Jerzy; Rosati, Giacomo; Trevisan, Gabriele

    2011-01-01

    We study the translational invariance of the relative-locality framework proposed in arXiv:1101.0931, which had been previously established only for the case of a single interaction. We provide an explicit example of boundary conditions at endpoints of worldlines, which indeed ensures the desired translational invariance for processes involving several interactions, even when some of the interactions are causally connected (particle exchange). We illustrate the properties of the associated relativistic description of distant observers within the example of a $\\kappa$-Poincar\\'e-inspired momentum-space geometry, with de Sitter metric and parallel transport governed by a non-metric and torsionful connection. We find that in such a theory simultaneously-emitted massless particles do not reach simultaneously a distant detector, as expected in light of the findings of arXiv:1103.5626 on the implications of non-metric connections. We also show that the theory admits a free-particle limit, where the relative-localit...

  9. Space Technology 5 Multipoint Observations of Temporal and Spatial Variability of Field-Aligned Currents

    Science.gov (United States)

    Le, G.; Wang, Y.; Slavin, J. A.; Strangeway, R. L.

    2009-01-01

    Space Technology 5 (ST5) is a constellation mission consisting of three microsatellites. It provides the first multipoint magnetic field measurements in low Earth orbit, which enables us to separate spatial and temporal variations. In this paper, we present a study of the temporal variability of field-aligned currents using the ST5 data. We examine the field-aligned current observations during and after a geomagnetic storm and compare the magnetic field profiles at the three spacecraft. The multipoint data demonstrate that mesoscale current structures, commonly embedded within large-scale current sheets, are very dynamic with highly variable current density and/or polarity in approx.10 min time scales. On the other hand, the data also show that the time scales for the currents to be relatively stable are approx.1 min for mesoscale currents and approx.10 min for large-scale currents. These temporal features are very likely associated with dynamic variations of their charge carriers (mainly electrons) as they respond to the variations of the parallel electric field in auroral acceleration region. The characteristic time scales for the temporal variability of mesoscale field-aligned currents are found to be consistent with those of auroral parallel electric field.

  10. Crew Earth Observations: Twelve Years of Documenting Earth from the International Space Station

    Science.gov (United States)

    Evans, Cynthia A.; Stefanov, William L.; Willis, Kimberley; Runco, Susan; Wilkinson, M. Justin; Dawson, Melissa; Trenchard, Michael

    2012-01-01

    The Crew Earth Observations (CEO) payload was one of the initial experiments aboard the International Space Station, and has been continuously collecting data about the Earth since Expedition 1. The design of the experiment is simple: using state-of-the-art camera equipment, astronauts collect imagery of the Earth's surface over defined regions of scientific interest and also document dynamic events such as storms systems, floods, wild fires and volcanic eruptions. To date, CEO has provided roughly 600,000 images of Earth, capturing views of features and processes on land, the oceans, and the atmosphere. CEO data are less rigorously constrained than other remote sensing data, but the volume of data, and the unique attributes of the imagery provide a rich and understandable view of the Earth that is difficult to achieve from the classic remote sensing platforms. In addition, the length-of-record of the imagery dataset, especially when combined with astronaut photography from other NASA and Russian missions starting in the early 1960s, provides a valuable record of changes on the surface of the Earth over 50 years. This time period coincides with the rapid growth of human settlements and human infrastructure.

  11. Observing with a space-borne gamma-ray telescope: selected results from INTEGRAL

    CERN Document Server

    Schanne, S

    2006-01-01

    The International Gamma-Ray Astrophysics Laboratory, i.e. the INTEGRAL satellite of ESA, in orbit since about 3 years, performs gamma-ray observations of the sky in the 15 keV to 8 MeV energy range. Thanks to its imager IBIS, and in particular the ISGRI detection plane based on 16384 CdTe pixels, it achieves an excellent angular resolution (12 arcmin) for point source studies with good continuum spectrum sensitivity. Thanks to its spectrometer SPI, based on 19 germanium detectors maintained at 85 K by a cryogenic system, located inside an active BGO veto shield, it achieves excellent spectral resolution of about 2 keV for 1 MeV photons, which permits astrophysical gamma-ray line studies with good narrow-line sensitivity. In this paper we review some goals of gamma-ray astronomy from space and present the INTEGRAL satellite, in particular its instruments ISGRI and SPI. Ground and in-flight calibration results from SPI are presented, before presenting some selected astrophysical results from INTEGRAL. In partic...

  12. Si and Fe depletion in Galactic star-forming regions observed by the Spitzer Space Telescope

    CERN Document Server

    Okada, Yoko; Miyata, Takashi; Okamoto, Yoshiko K; Sakon, Itsuki; Shibai, Hiroshi; Takahashi, Hidenori

    2008-01-01

    We report the results of the mid-infrared spectroscopy of 14 Galactic star-forming regions with the high-resolution modules of the Infrared Spectrograph (IRS) on board the Spitzer Space Telescope. We detected [SiII] 35um, [FeII] 26um, and [FeIII] 23um as well as [SIII] 33um and H2 S(0) 28um emission lines. Using the intensity of [NII] 122um or 205um and [OI] 146um or 63um reported by previous observations in four regions, we derived the ionic abundance Si+/N+ and Fe+/N+ in the ionized gas and Si+/O0 and Fe+/O0 in the photodissociation gas. For all the targets, we derived the ionic abundance of Si+/S2+ and Fe2+/S2+ for the ionized gas. Based on photodissociation and HII region models the gas-phase Si and Fe abundance are suggested to be 3-100% and <8% of the solar abundance, respectively, for the ionized gas and 16-100% and 2-22% of the solar abundance, respectively, for the photodissociation region gas. Since the [FeII] 26um and [FeIII] 23um emissions are weak, the high sensitivity of the IRS enables to de...

  13. Robust maximum likelihood estimation for stochastic state space model with observation outliers

    Science.gov (United States)

    AlMutawa, J.

    2016-08-01

    The objective of this paper is to develop a robust maximum likelihood estimation (MLE) for the stochastic state space model via the expectation maximisation algorithm to cope with observation outliers. Two types of outliers and their influence are studied in this paper: namely,the additive outlier (AO) and innovative outlier (IO). Due to the sensitivity of the MLE to AO and IO, we propose two techniques for robustifying the MLE: the weighted maximum likelihood estimation (WMLE) and the trimmed maximum likelihood estimation (TMLE). The WMLE is easy to implement with weights estimated from the data; however, it is still sensitive to IO and a patch of AO outliers. On the other hand, the TMLE is reduced to a combinatorial optimisation problem and hard to implement but it is efficient to both types of outliers presented here. To overcome the difficulty, we apply the parallel randomised algorithm that has a low computational cost. A Monte Carlo simulation result shows the efficiency of the proposed algorithms. An earlier version of this paper was presented at the 8th Asian Control Conference, Kaohsiung, Taiwan, 2011.

  14. TanDEM-X the Earth surface observation project from space level - basis and mission status

    Directory of Open Access Journals (Sweden)

    Jerzy Wiśniowski

    2015-03-01

    Full Text Available TanDEM-X is DLR (Deutsches Zentrum für Luft- und Raumfahrt the Earth surface observation project using high-resolution SAR interferometry. It opens a new era in space borne radar remote sensing. The system is based on two satellites: TerraSAR-X (TSX and TanDEM-X (TDX flying on the very close, strictly controlled orbits. This paper gives an overview of the radar technology and overview of the TanDEM-X mission concept which is based on several innovative technologies. The primary objective of the mission is to deliver a global digital elevation model (DEM with an unprecedented accuracy, which is equal to or surpass the HRTI-3 specifications (12 m posting, relative height accuracy ±2 m for slope < 20% and ±4 m for slope > 20% [8]. Beyond that, TanDEM-X provides a highly reconfigurable platform for the demonstration of new radar imaging techniques and applications.[b]Keywords[/b]: remote sensing, Bistatic SAR, digital elevation model (DEM, Helix formation, SAR interferomery, HRTI-3, synchronization

  15. OGLE-2015-BLG-0196: Ground-based Gravitational Microlens Parallax Confirmed By Space-Based Observation

    CERN Document Server

    Han, C; Gould, A; Zhu, Wei; Szymański, M K; Soszyński, I; Skowron, J; Mróz, P; Poleski, R; Pietrukowicz, P; Kozłowski, S; Ulaczyk, K; Pawlak, M; Yee, J C; Beichman, C; Novati, S Calchi; Carey, S; Bryden, C; Fausnaugh, M; Gaudi, B S; Henderson, Calen B; Shvartzvald, Y; Wibking, B

    2016-01-01

    In this paper, we present the analysis of the binary gravitational microlensing event OGLE-2015-BLG-0196. The event lasted for almost a year and the light curve exhibited significant deviations from the lensing model based on the rectilinear lens-source relative motion, enabling us to measure the microlens parallax. The ground-based microlens parallax is confirmed by the data obtained from space-based microlens observations using the {\\it Spitzer} telescope. By additionally measuring the angular Einstein radius from the analysis of the resolved caustic crossing, the physical parameters of the lens are determined up to the two-fold degeneracy: $u_00$ solutions caused by the well-known "ecliptic" degeneracy. It is found that the binary lens is composed of two M dwarf stars with similar masses $M_1=0.38\\pm 0.04\\ M_\\odot$ ($0.50\\pm 0.05\\ M_\\odot)$ and $M_2=0.38\\pm 0.04\\ M_\\odot$ ($0.55\\pm 0.06\\ M_\\odot$) and the distance to the lens is $D_{\\rm L}=2.77\\pm 0.23$ kpc ($3.30\\pm 0.29$ kpc). Here the physical parameter...

  16. Hubble space telescope observations of white dwarfs in the globular cluster M4

    CERN Document Server

    Richer, H B; Ibata, R A; Stetson, P B; Bell, R A; Bolte, M; Bond, H E; Harris, W E; Hesser, J E; Mandushev, G I; Pryor, C E; Richer, Harvey B; Fahlman, Gregory G; Ibata, Rodrigo A; Stetson, Peter B; Bell, Roger A; Bolte, Michael; Bond, Howard E; Harris, William E; Hesser, James E; Mandushev, Georgi; Pryor, Carlton

    1995-01-01

    With the Wide Field Planetary Camera 2 (WFPC2) on the Hubble Space Telescope, we have discovered in M4 (NGC 6121, C 1620-264) the first extensive sequence of cooling white dwarfs seen in a globular cluster. Adopting a distance modulus of (m-M)_V = 12.65 and a reddening of E(B-V) = 0.37, we show that the sequence, which extends over 9 < M_U < 13, is comprised of white dwarfs of mass \\sim 0.5 M_{\\odot}. The total mass loss from the present turnoff to the white dwarf sequence is 0.31 M_{\\odot} and the intrinsic dispersion in the mean mass appears to be < 0.05 M_{\\odot}. Both the location of the white dwarf cooling sequence in the cluster color-magnitude diagram and the cumulative luminosity function attest to the basic correctness and completeness of the physics in theoretical models for the upper three magnitudes of the observed white dwarf cooling sequence. To test the theory in globular clusters at cooling ages beyond \\sim 3 \\times 10^8 years will require deeper and more complete data.

  17. A search for FK Com candidates using Kepler Space Telescope observations: Analogs of HD 199178

    Science.gov (United States)

    Puzin, V. B.; Savanov, I. S.; Dmitrienko, E. S.

    2017-08-01

    Analysis of collected photometric observations obtained with the Kepler Space Telescope were used to select and study 33 objects with parameters corresponding to those of the FK Com starHD199178; these can be considered candidate stars of this type. In this final study, the four objects with the best light curves, which show the properties of their regular rotational modulation most clearly, were selected for detailed studies. The photometric analysis is based on all data currently available in the Kepler archive (covering almost four years). The rotational periods and estimated parameters of the objects' differential rotation are determined, and the longitudes of the dominant active regions on the surfaces found. For all four stars, the spot coverage is approximately 1% of the visible stellar surface area. The rotational periods and data on the stars'masses and radii fromtheMAST catalog are used to determine the rotation velocities projected onto the line of sight, which ranged from 12 to 21 km/s. Further studies will enable definite conclusions about how these stars are related to FK Com stars. If they are ultimately classified as FK Com stars, this will considerably increase the number of this rare type of star and the also number of rapidly rotating, single, late-type giants.

  18. Evidence for Type Ia Supernova Diversity from Ultraviolet Observations with the Hubble Space Telescope

    CERN Document Server

    Wang, Xiaofeng; Filippenko, Alexei V; Aldering, Greg; Antilogus, Pierre; Arnett, David; Baade, Dietrich; Baron, Eddie; Barris, Brian J; Benetti, Stefano; Bouchet, Patrice; Burrows, Adam S; Canal, Ramon; Cappellaro, Enrico; Carlberg, Raymond; di Carlo, Elisa; Challis, Peter; Crotts, Arlin; Danziger, John I; Della Valle, Massimo; Jack, Dennis; Fink, Michael; Foley, Ryan J; Fransson, Claes; Gal-Yam, Avishay; Garnavich, Peter; Gerardy, Chris L; Goldhaber, Gerson; Hamuy, Mario; Hillebrandt, Wolfgang; Hoeflich, Peter A; Holland, Stephen T; Holz, Daniel E; Hughes, John P; Jeffery, David J; Jha, Saurabh W; Kasen, Dan; Khokhlov, Alexei M; Kirshner, Robert P; Knop, Robert; Kozma, Cecilia; Krisciunas, Kevin; Kromer, Markus; Lee, Brian C; Leibundgut, Bruno; Lentz, Eric J; Leonard, Douglas C; Lewin, Walter H G; Li, Weidong; Livio, Mario; Lundqvist, Peter; Maoz, Dan; Matheson, Thomas; Mazzali, Paolo; Meikle, Peter; Miknaitis, Gajus; Milne, Peter; Mochnacki, Stefan; Nomoto, Ken'Ichi; Nugent, Peter E; Oran, Elaine; Panagia, Nino; Patat, Ferdinando; Perlmutter, Saul; Phillips, Mark M; Pinto, Philip; Poznanski, Dovi; Pritchet, Christopher J; Reinecke, Martin; Riess, Adam; Ruiz-Lapuente, Pilar; Scalzo, Richard; Schlegel, Eric M; Schmidt, Brian; Siegrist, James; Soderberg, Alicia M; Sollerman, Jesper; Sonneborn, George; Spadafora, Anthony; Spyromilio, Jason; Sramek, Richard A; Starrfield, Sumner G; Strolger, Louis G; Suntzeff, Nicholas B; Thomas, Rollin; Tonry, John L; Tornambe, Amedeo; Truran, James W; Turatto, Massimo; Turner, Michael; Van Dyk, Schuyler D; Weiler, Kurt; Wheeler, J Craig; Wood-Vasey, Michael; Woosley, Stan; Yamaoka, Hitoshi; Zhang, Tianmeng

    2011-01-01

    We present ultraviolet (UV) spectroscopy and photometry of four Type Ia supernovae (SNe 2004dt, 2004ef, 2005M, and 2005cf) obtained with the UV prism of the Advanced Camera for Surveys on the Hubble Space Telescope. This dataset provides unique spectral time series down to 2000 Angstrom. Significant diversity is seen in the near maximum-light spectra (~ 2000--3500 Angstrom) for this small sample. The corresponding photometric data, together with archival data from Swift Ultraviolet/Optical Telescope observations, provide further evidence of increased dispersion in the UV emission with respect to the optical. The peak luminosities measured in uvw1/F250W are found to correlate with the B-band light-curve shape parameter dm15(B), but with much larger scatter relative to the correlation in the broad-band B band (e.g., ~0.4 mag versus ~0.2 mag for those with 0.8 3 sigma), being brighter than normal SNe Ia such as SN 2005cf by ~0.9 mag and ~2.0 mag in the uvw1/F250W and uvm2/F220W filters, respectively. We show th...

  19. Space and Astrophysical Plasmas : Dromion solutions for an electron acoustic wave and its application to space observations

    Indian Academy of Sciences (India)

    S S Ghosh; A Sen; G S Lakhina

    2000-11-01

    The nonlinear evolution of an electron acoustic wave is shown to obey the Davey–Stewartson I equation which admits so called dromion solutions. The importance of these two dimensional localized solutions for recent satellite observations of wave structures in the day side polar cap regions is discussed and the parameter regimes for their existence is delineated.

  20. Earth Observations to Assess Impact of Hurricane Katrina on John C. Stennis Space Center

    Science.gov (United States)

    Graham, William D.; Ross, Kenton W.

    2007-01-01

    The peril from hurricanes to Space Operations Centers is real and is forecast to continue; Katrina, Rita, and Wilma of 2005 and Charley, Frances, Ivan, and Jeanne of 2004 are sufficient motivation for NASA to develop a multi-Center plan for preparedness and response. As was demonstrated at SSC (Stennis Space Center) in response to Hurricane Katrina, NASA Centers are efficiently activated as local command centers, playing host to Federal and State agencies and first responders to coordinate and provide evacuation, relocation, response, and recovery activities. Remote sensing decision support provides critical insight for managing NASA infrastructure and for assisting Center decision makers. Managers require geospatial information to manage the federal city. Immediately following Katrina, SSC s power and network connections were disabled, hardware was inoperative, technical staff was displaced and/or out of contact, and graphical decision support tools were non-existent or less than fully effective. Despite this circumstance, SSC EOC (Emergency Operations Center) implemented response operations to assess damage and to activate recovery plans. To assist Center Managers, the NASA ASP (Applied Sciences Program) made its archive of high-resolution data over the site available. In the weeks and months after the immediate crisis, NASA supplemented this data with high-resolution, post-Katrina imagery over SSC and much of the affected coastal areas. Much of the high-resolution imagery was made available through the Department of Defense Clear View contract and was distributed through U.S. Geological Survey Center for Earth Resources Observation and Science "Hurricane Katrina Disaster Response" Web site. By integrating multiple image data types with other information sources, ASP applied an all-source solutions approach to develop decision support tools that enabled managers to respond to critical issues, such as expedient access to infrastructure and deployment of resources

  1. Space-based Observation System Simulation Experiments for the Global Water Cycle: Information Tradeoffs, Model Diagnostics, and Exascale Computing

    Science.gov (United States)

    Reed, P. M.

    2011-12-01

    Global scale issues such as population growth, changing land-use, and climate change place our natural resources at the center of focus for a broad range of interdependent science, engineering, and policy problems. Our ability to mitigate and adapt to the accelerating rate of environmental change is critically dependent on our ability to observe and predict the natural, built, and social systems that define sustainability at the global scale. Despite the risks and challenges posed by global change, we are faced with critical risks to our ability to maintain and improve long term space-based observations of these changes. Despite consensus agreement on the critical importance of space-based Earth science, the fundamental challenge remains: How should we manage the severe tradeoffs and design challenges posed by maximizing the value of existing and proposed spaced-based Earth observation systems? Addressing this question requires transformative innovations in the design and management of spaced-based Earth observation systems that effectively take advantage of massively parallel computing architectures to enable the discovery and exploitation of critical mission tradeoffs using high-resolution space-based observation system simulation events (OSSEs) that simulate the global water cycle data that would result from sensing innovations and evaluates their merit with carefully constructed prediction and management benchmarks.

  2. Hubble Space Telescope observations of Orion Nebula, Helix Nebula, and NGC 6822

    Science.gov (United States)

    Spitzer, Lyman; Fitzpatrick, Ed

    1999-01-01

    This grant covered the major part of the work of the Principal Investigator and his collaborators as a Guaranteed Time Observer on the Hubble Space Telescope. The work done naturally divided itself into two portions the first being study of nebular objects and the second investigation of the interstellar medium between stars. The latter investigation was pursued through a contract with Princeton University, with Professor Lyman Spitzer as the supervising astronomer, assisted by Dr. Ed Fitzpatrick. Following the abrupt death of Professor Spitzer, his responsibilities were shifted to Dr. Fitzpatrick. When Dr. Fitzpatrick relocated to Villanova University the concluding work on that portion of this grant was concluded under a direct service arrangement. This program has been highly successful and the resulting publications in scientific journals are listed below. To the scientist, this is the bottom line, so that I shall simply try to describe the general nature of what was accomplished. There were three nebular programs conducted, one on the Orion Nebula, the second on the Helix Nebula, and the third on NGC 6822. The largest program was that on the Orion Nebula. This involved both HST observations and supporting groundbased observations obtained with a variety of instruments, including the Coude Feed Telescope at the Kitt Peak National observatory in Arizona, the Cerro Tololo observatory in Chile, and the Keck Observatory on Mauna Kea, Hawaii. Moreover, considerable theoretical modeling was done and all of the data analysis was performed at the Rice University in Houston, except for the PI's period of sabbatical leave (6-96 through 7-97) when he was based at the Max Planck Institute for Astronomy in Heidelberg, Germany. The Orion Nebula program was the most productive part, resulting in numerous papers, but more important in the discovery of a new class of objects, for which we coined the name "proplyds". The proplyds are protoplanetary disks surrounding very young

  3. Space-based Observational Constraints for 1-D Plume Rise Models

    Science.gov (United States)

    Martin, Maria Val; Kahn, Ralph A.; Logan, Jennifer A.; Paguam, Ronan; Wooster, Martin; Ichoku, Charles

    2012-01-01

    We use a space-based plume height climatology derived from observations made by the Multi-angle Imaging SpectroRadiometer (MISR) instrument aboard the NASA Terra satellite to evaluate the ability of a plume-rise model currently embedded in several atmospheric chemical transport models (CTMs) to produce accurate smoke injection heights. We initialize the plume-rise model with assimilated meteorological fields from the NASA Goddard Earth Observing System and estimated fuel moisture content at the location and time of the MISR measurements. Fire properties that drive the plume-rise model are difficult to estimate and we test the model with four estimates for active fire area and four for total heat flux, obtained using empirical data and Moderate Resolution Imaging Spectroradiometer (MODIS) re radiative power (FRP) thermal anomalies available for each MISR plume. We show that the model is not able to reproduce the plume heights observed by MISR over the range of conditions studied (maximum r2 obtained in all configurations is 0.3). The model also fails to determine which plumes are in the free troposphere (according to MISR), key information needed for atmospheric models to simulate properly smoke dispersion. We conclude that embedding a plume-rise model using currently available re constraints in large-scale atmospheric studies remains a difficult proposition. However, we demonstrate the degree to which the fire dynamical heat flux (related to active fire area and sensible heat flux), and atmospheric stability structure influence plume rise, although other factors less well constrained (e.g., entrainment) may also be significant. Using atmospheric stability conditions, MODIS FRP, and MISR plume heights, we offer some constraints on the main physical factors that drive smoke plume rise. We find that smoke plumes reaching high altitudes are characterized by higher FRP and weaker atmospheric stability conditions than those at low altitude, which tend to remain confined

  4. Observation and simulation of space-charge effects in a radio-frequency photoinjector using a transverse multibeamlet distribution

    Directory of Open Access Journals (Sweden)

    M. Rihaoui

    2009-12-01

    Full Text Available We report on an experimental study of space-charge effects in a radio-frequency (rf photoinjector. A 5 MeV electron bunch, consisting of a number of beamlets separated transversely, was generated in an rf photocathode gun and propagated in the succeeding drift space. The collective interaction of these beamlets was studied for different experimental conditions. The experiment allowed the exploration of space-charge effects and its comparison with 3D particle-in-cell simulations. Our observations also suggest the possible use of a multibeam configuration to tailor the transverse distribution of an electron beam.

  5. Gender-sensitive observations in public spaces as a teaching tool

    NARCIS (Netherlands)

    Droogleever Fortuijn, J.

    2009-01-01

    Public spaces can be seen as arenas where gendered social roles, relations and identities are (re)produced, represented and contested. Because of their (assumed) public character - crowded, open, accessible and visible - these spaces are extremely useful as «observatories» for teaching and learning

  6. Gender-sensitive observations in public spaces as a teaching tool

    NARCIS (Netherlands)

    Droogleever Fortuijn, J.

    2009-01-01

    Public spaces can be seen as arenas where gendered social roles, relations and identities are (re)produced, represented and contested. Because of their (assumed) public character - crowded, open, accessible and visible - these spaces are extremely useful as «observatories» for teaching and learning

  7. Using Mobile Technology to Observe Student Study Behaviors and Track Library Space Usage

    Science.gov (United States)

    Thompson, Susan

    2015-01-01

    Libraries have become increasingly interested in studying the use of spaces within their buildings. Traditional methods for tracking library building use, such as gate counts, provide little information on what patrons do once they are in the library; therefore, new methods for studying space usage are being developed. Particularly promising are…

  8. Evidence for Type Ia Supernova Diversity from Ultraviolet Observations with the Hubble Space Telescope

    Science.gov (United States)

    Wang, Xiaofeng; Wang, Lifan; Filippenko, Alexei; Baron, Eddie; Kromer, Markus; Jack, Dennis; Zhang, Tianmeng; Aldering, Greg; Antilogus, Pierre; Arnett, W. David; hide

    2012-01-01

    We present ultraviolet (UV) spectroscopy and photometry of four Type Ia supernovae (SNe 2004dt, 2004ef, 2005M, and 2005cf) obtained with the UV prism of the Advanced Camera for Surveys on the Hubble Space Telescope, This dataset provides unique spectral time series down to 2000 A. Significant diversity is seen in the near-maximum-light spectra (approx.2000-3500 A) for this small sample. The corresponding photometric data, together with archival data from Swift Ultraviolet/Optical Telescope observations, provide further evidence of increased dispersion in the UV emission with respect to the optical. The peak luminosities measured in the uvw lIF250W filter are found to correlate with the B-band light-curve shape parameter .(Delta)m15(B), but with much larger scatter relative to the correlation in the broad-band B band (e.g., approx. 0.4 mag versus approx. 0.2 mag for those with 0.8 3(sigma), being brighter than normal SNe Ia such as SN 2005cf by approx. 0,9 mag and approx. 2.0 mag in the uvwl1F250W and uvm2/F220W filters, respectively. We show that different progenitor metallicity or line-expansion velocities alone cannot explain such a large discrepancy. Viewing-angle effects, such as due to an asymmetric explosion, may have a significant influence on the flux emitted in the UV region. Detailed modeling is needed to disentangle and quantify the above effects

  9. Next Generation Forest Structure Measurements from Space: Synergism of NASA's NISAR and GEDI Observations

    Science.gov (United States)

    Saatchi, S. S.; Xu, L.; Yu, Y.

    2016-12-01

    Post-2020 will witness a series of new observations from NASA and ESA spaceborne missions dedicated to measurements of aboveground forest structure and biomass (AGB). These measurements are designed to significantly reduce the uncertainty in terrestrial carbon cycle by providing globally consistent estimates of forest aboveground carbon stocks and dynamics from land use and climate related changes. NASA's Global Ecosystem Dynamics Investigation (GEDI), NASA and ISRO SAR (NISAR), and ESA's BIOMASS (launch in 2020-21) missions, which are scheduled for launch in the next three to five years, share similar objectives for estimation of forest structure and aboveground biomass (AGB). The NISAR mission will measure above ground woody vegetation biomass at spatial resolution of 100 m (1-ha) annually over the lifetime of the mission providing fine grain products of carbon stocks and changes over a range of biomass limited to 100 Mg/ha. The upper threshold of 100 Mg/ha is set to reflect the sensitivity of L-band backscatter measurements to biomass and allowing coverage of more than 50% of the global forests and the entire area of remaining woody vegetation. This sensitivity will allow NISAR to quantify the carbon stocks and changes of the most dynamic and variable component of global vegetation with significant contribution to the global carbon cycle and climate science. We examine the sensitivity of NISAR in estimating AGB in different forest types and demonstrate how the NISAR and GEDI data can be combined in a machine-learning algorithm to develop synergistic products of global forest height and AGB. The synergistic approach extends the range of biomass estimation for NISAR mission and allows extrapolation of GEDI LiDAR samples to contiguous maps of height metrics. AcknowledgementsThe research was carried out partially at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

  10. EVIDENCE FOR TYPE Ia SUPERNOVA DIVERSITY FROM ULTRAVIOLET OBSERVATIONS WITH THE HUBBLE SPACE TELESCOPE

    Energy Technology Data Exchange (ETDEWEB)

    Wang Xiaofeng [Physics Department and Tsinghua Center for Astrophysics (THCA), Tsinghua University, Beijing 100084 (China); Wang Lifan [Physics and Astronomy Department, Texas A and M University, College Station, TX 77843 (United States); Filippenko, Alexei V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Baron, Eddie [Department of Physics, University of Oklahoma, Norman, OK 73019 (United States); Kromer, Markus [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Str. 1, 85748 Garching (Germany); Jack, Dennis [Hamburger Sternwarte, Gojenbergsweg 112, 21029 Hamburg (Germany); Zhang Tianmeng [National Astronomical Observatory of China, Chinese Academy of Sciences, Beijing 100012 (China); Aldering, Greg [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Antilogus, Pierre [Laboratoire de Physique Nucleaire des Hautes Energies, Paris (France); Arnett, W. David [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); Baade, Dietrich [European Southern Observatory, 85748 Garching (Germany); Barris, Brian J. [Institute for Astronomy, University of Hawaii, Honolulu, HI 96822 (United States); Benetti, Stefano; Cappellaro, Enrico [Osservatorio Astronomico di Padova, 35122 Padova (Italy); Bouchet, Patrice [CEA/DSM/DAPNIA/Service d' Astrophysique, 91191 Gif-sur-Yvette Cedex (France); Burrows, Adam S. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Canal, Ramon [Department d' Astronomia i Meterorologia, Universidad de Barcelona, Barcelona 8007 (Spain); Carlberg, Raymond G. [Department of Astronomy and Astrophysics, University of Toronto, Toronto, ON M5S 3J3 (Canada); Di Carlo, Elisa [INAF, Osservatorio Astronomico di Teramo, 64100 Teramo (Italy); Challis, Peter J., E-mail: wang_xf@mail.tsinghua.edu.cn [Harvard/Smithsonian Center Astrophysics, Cambridge, MA 02138 (United States); and others

    2012-04-20

    We present ultraviolet (UV) spectroscopy and photometry of four Type Ia supernovae (SNe 2004dt, 2004ef, 2005M, and 2005cf) obtained with the UV prism of the Advanced Camera for Surveys on the Hubble Space Telescope. This data set provides unique spectral time series down to 2000 A. Significant diversity is seen in the near-maximum-light spectra ({approx}2000-3500 A) for this small sample. The corresponding photometric data, together with archival data from Swift Ultraviolet/Optical Telescope observations, provide further evidence of increased dispersion in the UV emission with respect to the optical. The peak luminosities measured in the uvw1/F250W filter are found to correlate with the B-band light-curve shape parameter {Delta}m{sub 15}(B), but with much larger scatter relative to the correlation in the broadband B band (e.g., {approx}0.4 mag versus {approx}0.2 mag for those with 0.8 mag < {Delta}m{sub 15}(B) < 1.7 mag). SN 2004dt is found as an outlier of this correlation (at > 3{sigma}), being brighter than normal SNe Ia such as SN 2005cf by {approx}0.9 mag and {approx}2.0 mag in the uvw1/F250W and uvm2/F220W filters, respectively. We show that different progenitor metallicity or line-expansion velocities alone cannot explain such a large discrepancy. Viewing-angle effects, such as due to an asymmetric explosion, may have a significant influence on the flux emitted in the UV region. Detailed modeling is needed to disentangle and quantify the above effects.

  11. Spitzer Space Telescope Observations of the Nucleus of Comet 103P/Hartley 2

    Science.gov (United States)

    Lisse, C. M.; Fernandez, Y. R.; Reach, W. T.; Bauer, J. M.; A’Hearn, M. F.; Farnham, T. L.; Groussin, O.; Belton, M. J.; Meech, K. J.; Snodgrass, C. D.

    2009-09-01

    We have used the Spitzer Space Telescope InfraRed Spectrograph (IRS) 22-μm peakup array to observe thermal emission from the nucleus and trail of comet 103P/Hartley 2, the target of NASA’s Deep Impact Extended Investigation (DIXI). The comet was observed on UT 2008 August 12 and 13, while 5.5 AU from the Sun. We obtained two 200 frame sets of photometric imaging over a 2.7 hr period. To within the errors of the measurement, we find no detection of any temporal variation between the two images. The comet showed extended emission beyond a point source in the form of a faint trail directed along the comet’s antivelocity vector. After modeling and removing the trail emission, a NEATM model for the nuclear emission with beaming parameter of 0.95 ± 0.20 indicates a small effective radius for the nucleus of 0.57 ± 0.08 km and low geometric albedo 0.028 ± 0.009 (1σ). With this nucleus size and a water production rate of 3 × 1028 molecules s-1 at perihelion, we estimate that ∼100% of the surface area is actively emitting volatile material at perihelion. Reports of emission activity out to ∼5 AU support our finding of a highly active nuclear surface. Compared to Deep Impact’s first target, comet 9P/Tempel 1, Hartley 2’s nucleus is one-fifth as wide (and about one-hundredth the mass) while producing a similar amount of outgassing at perihelion with about 13 times the active surface fraction. Unlike Tempel 1, comet Hartley 2 should be highly susceptible to jet driven spin-up torques, and so could be rotating at a much higher frequency. Since the amplitude of nongravitational forces are surprisingly similar for both comets, close to the ensemble average for ecliptic comets, we conclude that comet Hartley 2 must have a much more isotropic pattern of time-averaged outgassing from its nuclear surface. Barring a catastrophic breakup or major fragmentation event, the comet should be able to survive up to another 100 apparitions (∼700 yr) at its current rate of

  12. The Main Pillar: Assessment of Space Weather Observational Asset Performance Supporting Nowcasting, Forecasting and Research to Operations

    Science.gov (United States)

    Posner, Arik; Hesse, Michael; SaintCyr, Chris

    2014-01-01

    Space weather forecasting critically depends upon availability of timely and reliable observational data. It is therefore particularly important to understand how existing and newly planned observational assets perform during periods of severe space weather. Extreme space weather creates challenging conditions under which instrumentation and spacecraft may be impeded or in which parameters reach values that are outside the nominal observational range. This paper analyzes existing and upcoming observational capabilities for forecasting, and discusses how the findings may impact space weather research and its transition to operations. A single limitation to the assessment is lack of information provided to us on radiation monitor performance, which caused us not to fully assess (i.e., not assess short term) radiation storm forecasting. The assessment finds that at least two widely spaced coronagraphs including L4 would provide reliability for Earth-bound CMEs. Furthermore, all magnetic field measurements assessed fully meet requirements. However, with current or even with near term new assets in place, in the worst-case scenario there could be a near-complete lack of key near-real-time solar wind plasma data of severe disturbances heading toward and impacting Earth's magnetosphere. Models that attempt to simulate the effects of these disturbances in near real time or with archival data require solar wind plasma observations as input. Moreover, the study finds that near-future observational assets will be less capable of advancing the understanding of extreme geomagnetic disturbances at Earth, which might make the resulting space weather models unsuitable for transition to operations.

  13. An Investigation of Aural Space inside Mousa Broch by Observation and Analysis of Sound and Light

    Directory of Open Access Journals (Sweden)

    Dave Thomas

    2011-07-01

    Full Text Available This project emphasises the unique character and construction of Mousa broch, questions the model of Mousa broch as a roofed home (an interpretation adopted by Historic Scotland in 2002 and considers the way in which sound and light informs our understanding of the spaces contained within its structure. Underpinning the approach to data collection was the architectural concept of aural space. The author attempts to convey an impression of aural space inside Mousa broch by the creation of an audio-visual record supported by acoustic analysis, archaeological discussion, and an architectural breakdown of the spaces within the broch structure. Audio recordings, sound samples, photographs and movies were made on Mousa island and inside Mousa broch during the period of the Summer solstice of 2009.

  14. Preliminary design of a satellite observation system for Space Station Freedom

    Science.gov (United States)

    Cabe, Greg (Editor); Gallagher, Chris; Wilson, Brian; Rehfeld, James; Maurer, Alexa; Stern, Dan; Nualart, Jaime; Le, Xuan-Trang

    1992-01-01

    Degobah Satellite Systems (DSS), in cooperation with the University Space Research Association (USRA), NASA - Johnson Space Center (JSC), and the University of Texas, has completed the preliminary design of a satellite system to provide inexpensive on-demand video images of all or any portion of Space Station Freedom (SSF). DSS has narrowed the scope of the project to complement the work done by Mr. Dennis Wells at Johnson Space Center. This three month project has resulted in completion of the preliminary design of AERCAM, the Autonomous Extravehicular Robotic Camera, detailed in this design report. This report begins by providing information on the project background, describing the mission objectives, constraints, and assumptions. Preliminary designs for the primary concept and satellite subsystems are then discussed in detail. Included in the technical portion of the report are detailed descriptions of an advanced imaging system and docking and safing systems that ensure compatibility with the SSF. The report concludes by describing management procedures and project costs.

  15. Real-Time Delivery of Global Environmental Observation Data From Space-Based Sensors using the Inmarsat BGAN System

    Science.gov (United States)

    McCormick, C. C.; Lenz, C.; Yunck, T.

    2010-12-01

    This presentation describes a technique and the resulting improvements in quality and latency related to the collection, processing, and distribution of environmental observation data that is collected globally, from space-based sensors. The technique employs a newly developed transceiver which allows a spacecraft in low-earth orbit to communicate with the ground in real-time, globally, via the existing constellation of Inmarsat commercial communication satellites. The ability to communicate with the space-based platform and its sensors at all times, with data latencies measured in milliseconds rather than tens of minutes opens up new opportunities for the collection and application of data captured by sensors in space, as well as the ability for closed-loop tasking of the space based instruments or uploading large data sets to the instruments. The authors describe the technology involved, followed by the description of how this technology is being applied for the real-time collection of space weather observations. The process of collection, data transfer, processing, and distribution is described, highlighting the areas where this new technology improves value of the collected data with the reduced latency. Finally, the paper provides a glance at other applications and data products where this technology and approach could be employed to improve data value and to develop new applications of data collected on space-based platforms.

  16. Tachyphylaxis associated with repeated epidural injections of lidocaine is not related to changes in distribution or the rate of elimination from the epidural space

    DEFF Research Database (Denmark)

    Mogensen, T; Simonsen, L; Scott, N B

    1989-01-01

    technetium-99m diethylenetriaminepentaacetate [99mTc-DTPA]) and elimination of lidocaine from the epidural space (as measured by serum concentrations of lidocaine) was investigated in 18 patients undergoing minor surgery during lumbar epidural analgesia. Twelve patients received four injections of 20 mL of 2......% lidocaine at 2-hr intervals. Epidural distribution was assessed by injection of 99mTc-DTPA diluted in saline on the preoperative day and diluted in an equal volume of 2% lidocaine on the morning before surgery and again after the fourth injection of lidocaine 6 hr later. The distribution of 99mTc-DTPA...

  17. Development of signal processing system of avalanche photo diode for space observations by Astro-H

    Energy Technology Data Exchange (ETDEWEB)

    Ohno, M., E-mail: ohno@hep01.hepl.hiroshima-u.ac.jp [Department of Physical Sciences, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8516 (Japan); Goto, K.; Hanabata, Y.; Takahashi, H.; Fukazawa, Y. [Department of Physical Sciences, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8516 (Japan); Yoshino, M.; Saito, T.; Nakamori, T.; Kataoka, J. [Research Institute for Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555 (Japan); Sasano, M.; Torii, S.; Uchiyama, H.; Nakazawa, K. [Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Watanabe, S.; Kokubun, M.; Ohta, M.; Sato, T.; Takahashi, T. [Institute of Space and Astronautial Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo-ku Sagamihara, Kanagawa 252-5120 (Japan); Tajima, H. [Cosmic-ray Research Facility, Solar-Terrestrial Environment Laboratory, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601 (Japan)

    2013-01-21

    Astro-H is the sixth Japanese X-ray space observatory which will be launched in 2014. Two of onboard instruments of Astro-H, Hard X-ray Imager and Soft Gamma-ray Detector are surrounded by many number of large Bismuth Germanate (Bi{sub 4}Ge{sub 3}O{sub 12}; BGO) scintillators. Optimum readout system of scintillation lights from these BGOs are essential to reduce the background signals and achieve high performance for main detectors because most of gamma-rays from out of field-of-view of main detectors or radio-isotopes produced inside them due to activation can be eliminated by anti-coincidence technique using BGO signals. We apply Avalanche Photo Diode (APD) for light sensor of these BGO detectors since their compactness and high quantum efficiency make it easy to design such large number of BGO detector system. For signal processing from APDs, digital filter and other trigger logics on the Field-Programmable Gate Array (FPGA) is used instead of discrete analog circuits due to limitation of circuit implementation area on spacecraft. For efficient observations, we have to achieve as low threshold of anti-coincidence signal as possible by utilizing the digital filtering. In addition, such anti-coincident signals should be sent to the main detector within 5μs to make it in time to veto the A–D conversion. Considering this requirement and constraint from logic size of FPGA, we adopt two types of filter, 8 delay taps filter with only 2 bit precision coefficient and 16 delay taps filter with 8 bit precision coefficient. The data after former simple filter provides anti-coincidence signal quickly in orbit, and the latter filter is used for detail analysis after the data is down-linked. -- Highlights: ► We develop digital signal processing system of APD for Astro-H. ► We apply two types of digital filter instead of discrete analog circuit. ► By optimization, comparable or better energy threshold to analog shaper is archived. ► Developed digital filter works

  18. Airglow Observation with IMAP/ VISI on the International Space Station: Current status and simulation

    Science.gov (United States)

    Perwitasari, S.; Sakanoi, T.; Yamazaki, A.; Otsuka, Y.; Akiya, Y.; Saito, A.

    2012-12-01

    The Visible and near-Infrared Spectral Imager (VISI) of the IMAP mission was launched successfully by H-IIB/HTV3 on July 21 2012. At this moment HTV3 is docked onto the International Space Station (ISS), and VISI is scheduled to be installed on the exposed facility within a week. VISI will be operated in the nightside hemisphere in the range of +/- 51 deg. GLAT, and measure the airglow emissions of OI at 630 nm, the OH Meinel band at 730 nm and the O2 atmospheric band (0-0) at 762 nm at an altitude of ~400 km with typical spatial resolution of 16 - 50 km. Since the influence of cloud reflections of moonlight is overlapped with the airglow pattern in the visible wavelength range, the precise subtraction of the cloud influence is a key issue of this mission. Therefore, a simulation work to study on how much the surface albedo on the cloud top will affect the data is critically important. The height profiles of volume emission rates were estimated for O2 and OH airglows with the MSIS models, and then the airglow intensities were integrated along the line-of-sight direction. The cloud pattern was estimated based on the realistic data measured with a geostationary climate satellite. The simulation result shows that for OH Meinel at 730 nm, the moonlight reflection during the first/last quarter will increase the brightness of the airglow by factor of 1.5-2 and ~5 for full moon phase. Meanwhile, for O2 atmospheric band (0-0) at 762 nm, the simulation result shows that there's no significant (structured) background, even during the full moon phase. We will report the quantitative effect of cloud albedo on the airglow pattern, and discuss the physical parameters those expected to be derived from the VISI data. Concerning on the operation of VISI, we will carry out the initial function check by the middle of August, and start nominal observation within a few months. Thus, we will also report the current status and initial result of VISI.

  19. Poster: Observing change in crowded data sets in 3D space - Visualizing gene expression in human tissues

    KAUST Repository

    Rogowski, Marcin

    2013-03-01

    We have been confronted with a real-world problem of visualizing and observing change of gene expression between different human tissues. In this paper, we are presenting a universal representation space based on two-dimensional gel electrophoresis as opposed to force-directed layouts encountered most often in similar problems. We are discussing the methods we devised to make observing change more convenient in a 3D virtual reality environment. © 2013 IEEE.

  20. Observations of the Hubble Deep Field with the Infrared Space Observatory .1. Data reduction, maps and sky coverage

    DEFF Research Database (Denmark)

    Serjeant, S.B.G.; Eaton, N.; Oliver, S.J.

    1997-01-01

    We present deep imaging at 6.7 and 15 mu m from the CAM instrument on the Infrared Space Observatory (ISO), centred on the Hubble Deep Field (HDF). These are the deepest integrations published to date at these wavelengths in any region of sky. We discuss the observational strategy and the data...

  1. Hubble Space Telescope STIS observations of GRB 000301C: CCD imaging and near-ultraviolet MAMA spectroscopy

    DEFF Research Database (Denmark)

    Smette, A.; Fruchter, A.S.; Gull, T.R.

    2001-01-01

    We present Space Telescope Imaging Spectrograph observations of the optical transient (OT) counterpart of the c-ray burster GRB 000301C obtained 5 days after the burst, on 2000 March 6. CCD clear-aperture imaging reveals a R similar or equal to 21.50 +/- 0.15 source with no apparent host galaxy. ...

  2. Hubble Space Telescope STIS Observations of GRB 000301C: CCD Imaging and Near-Ultraviolet MAMA Spectroscopy

    NARCIS (Netherlands)

    Smette, A.; Fruchter, A.S.; Gull, Th.R.; Sahu, K.C.; Petro, L.; Ferguson, H.; Rhoads, J.; Lindler, D.J.; Wijers, R.A.M.J.

    2001-01-01

    We present Space Telescope Imaging Spectrograph observations of the optical transient (OT) counterpart of the gamma-ray burster GRB 000301C obtained 5 days after the burst, on 2000 March 6. CCD clear-aperture imaging reveals a R~=21.50+/-0.15 source with no apparent host galaxy. An 8000 s, 1150

  3. Hubble Space Telescope STIS Observations of GRB 000301C: CCD Imaging and Near-Ultraviolet MAMA Spectroscopy

    NARCIS (Netherlands)

    Smette, A.; Fruchter, A.S.; Gull, Th.R.; Sahu, K.C.; Petro, L.; Ferguson, H.; Rhoads, J.; Lindler, D.J.; Wijers, R.A.M.J.

    2001-01-01

    We present Space Telescope Imaging Spectrograph observations of the optical transient (OT) counterpart of the gamma-ray burster GRB 000301C obtained 5 days after the burst, on 2000 March 6. CCD clear-aperture imaging reveals a R~=21.50+/-0.15 source with no apparent host galaxy. An 8000 s, 1150 Å

  4. Quantifying spatial and temporal variability in atmospheric ammonia with in situ and space-based observations--article

    Science.gov (United States)

    Ammonia plays an important role in many biogeochemical processes, yet atmospheric mixing ratios are not well known. Recently, methods have been developed for retrieving NH3 from space-based observations, but they have not been compared to in situ measurements. We have conducted a...

  5. Hubble Space Telescope First Observations of the Brightest Stars in the Virgo Galaxy M100 = NGC 4321

    Science.gov (United States)

    Freedman, W. L.; Madore, B. F.; Stetson, P. B.; Hughes, S. M. G.; Holtzman, J. A.; Mould, J. R.; Trauger, J. T.; Gallagher, J. S., III; Ballester, G. E.; Burrows, C. J.; Casertano, S.; Clarke, J. T; Crisp, D.; Ferrarese, L.; Ford, H.; Graham, J. A.; Griffiths, R. E.; Hester, J. J.; Hill, R.; Hoessel, J. G.; Huchra, J.; Kennicutt, R. C.; Scowen, P. A.; Sparks, B.; Stapelfeldt, K. R.

    1994-01-01

    As part of both the Early Release Observations fromthe Hubble Space Telescope and the Key PRoject on the Extragalctic Distance Scale, we have obtained multi-wavelength BVR WFPC2 images for the face-on Virgo cluster spiral galaxy M11 = NGC 4321.

  6. Primary Dendrite Array Morphology: Observations from Ground-based and Space Station Processed Samples

    Science.gov (United States)

    Tewari, Surendra; Rajamure, Ravi; Grugel, Richard; Erdmann, Robert; Poirier, David

    2012-01-01

    Influence of natural convection on primary dendrite array morphology during directional solidification is being investigated under a collaborative European Space Agency-NASA joint research program, "Microstructure Formation in Castings of Technical Alloys under Diffusive and Magnetically Controlled Convective Conditions (MICAST)". Two Aluminum-7 wt pct Silicon alloy samples, MICAST6 and MICAST7, were directionally solidified in microgravity on the International Space Station. Terrestrially grown dendritic monocrystal cylindrical samples were remelted and directionally solidified at 18 K/cm (MICAST6) and 28 K/cm (MICAST7). Directional solidification involved a growth speed step increase (MICAST6-from 5 to 50 micron/s) and a speed decrease (MICAST7-from 20 to 10 micron/s). Distribution and morphology of primary dendrites is currently being characterized in these samples, and also in samples solidified on earth under nominally similar thermal gradients and growth speeds. Primary dendrite spacing and trunk diameter measurements from this investigation will be presented.

  7. Primary Dendrite Array: Observations from Ground-Based and Space Station Processed Samples

    Science.gov (United States)

    Tewari, Surendra N.; Grugel, Richard N.; Erdman, Robert G.; Poirier, David R.

    2012-01-01

    Influence of natural convection on primary dendrite array morphology during directional solidification is being investigated under a collaborative European Space Agency-NASA joint research program, Microstructure Formation in Castings of Technical Alloys under Diffusive and Magnetically Controlled Convective Conditions (MICAST). Two Aluminum-7 wt pct Silicon alloy samples, MICAST6 and MICAST7, were directionally solidified in microgravity on the International Space Station. Terrestrially grown dendritic monocrystal cylindrical samples were remelted and directionally solidified at 18 K per centimeter (MICAST6) and 28 K per centimeter (MICAST7). Directional solidification involved a growth speed step increase (MICAST6-from 5 to 50 millimeters per second) and a speed decrease (MICAST7-from 20 to 10 millimeters per second). Distribution and morphology of primary dendrites is currently being characterized in these samples, and also in samples solidified on earth under nominally similar thermal gradients and growth speeds. Primary dendrite spacing and trunk diameter measurements from this investigation will be presented.

  8. Repeat-until-success quantum repeaters

    Science.gov (United States)

    Bruschi, David Edward; Barlow, Thomas M.; Razavi, Mohsen; Beige, Almut

    2014-09-01

    We propose a repeat-until-success protocol to improve the performance of probabilistic quantum repeaters. Conventionally, these rely on passive static linear-optics elements and photodetectors to perform Bell-state measurements (BSMs) with a maximum success rate of 50%. This is a strong impediment for entanglement swapping between distant quantum memories. Every time a BSM fails, entanglement needs to be redistributed between the corresponding memories in the repeater link. The key ingredients of our scheme are repeatable BSMs. Under ideal conditions, these turn probabilistic quantum repeaters into deterministic ones. Under realistic conditions, our protocol too might fail. However, using additional threshold detectors now allows us to improve the entanglement generation rate by almost orders of magnitude, at a nominal distance of 1000 km, compared to schemes that rely on conventional BSMs. This improvement is sufficient to make the performance of our scheme comparable to the expected performance of some deterministic quantum repeaters.

  9. Swarm Utilisation Analysis: LEO satellite observations for the ESA's SSA Space Weather network

    Science.gov (United States)

    Kervalishvili, Guram; Stolle, Claudia; Rauberg, Jan; Olsen, Nils; Vennerstrøm, Susanne; Gullikstad Johnsen, Magnar; Hall, Chris

    2017-04-01

    ESA's (European Space Agency) constellation mission Swarm was successfully launched on 22 November 2013. The three satellites achieved their final constellation on 17 April 2014 and since then Swarm-A and Swarm-C orbiting the Earth at about 470 km (flying side-by-side) and Swarm-B at about 520 km altitude. Each of Swarm satellite carries instruments with high precision to measure magnetic and electric fields, neutral and plasma densities, and TEC (Total Electron Content) for which a dual frequency GPS receiver is used. SUA (Swarm Utilisation Analysis) is a project of the ESA's SSA (Space Situational Awareness) SWE (Space Weather) program. Within this framework GFZ (German Research Centre for Geosciences, Potsdam, Germany) and DTU (National Space Institute, Kongens Lyngby, Denmark) have developed two new Swarm products ROT (Rate Of change of TEC) and PEJ (Location and intensity level of Polar Electrojets), respectively. ROT is derived as the first time derivative from the Swarm measurements of TEC at 1 Hz sampling. ROT is highly relevant for users in navigation and communications: strong plasma gradients cause GPS signal degradation or even loss of GPS signal. Also, ROT is a relevant space weather asset irrespective of geomagnetic activity, e.g., high amplitude values of ROT occur during all geomagnetic conditions. PEJ is derived from the Swarm measurements of the magnetic field strength at 1 Hz sampling. PEJ has a high-level importance for power grid companies since the polar electrojet is a major cause for ground-induced currents. ROT and PEJ together with five existing Swarm products TEC, electron density, IBI (Ionospheric Bubble Index), FAC (Field-Aligned Current), and vector magnetic field build the SUA service prototype. This prototype will be integrated into ESA's SSA Space Weather network as a federated service and will be available soon from ESA's SSA SWE Ionospheric Weather and Geomagnetic Conditions Expert Service Centres (ESCs).

  10. Estimation of acute oral toxicity using the No Observed Adverse Effect Level (NOAEL) from the 28 day repeated dose toxicity studies in rats.

    Science.gov (United States)

    Bulgheroni, Anna; Kinsner-Ovaskainen, Agnieszka; Hoffmann, Sebastian; Hartung, Thomas; Prieto, Pilar

    2009-02-01

    Acute systemic toxicity is one of the areas of particular concern due to the 2009 deadline set by the 7th Amendment of the Cosmetics Directive (76/768/EEC), which introduces a testing and marketing ban of cosmetic products with ingredients tested on animals. The scientific community is putting considerable effort into developing and validating non-animal alternatives in this area. However, it is unlikely that validated and regulatory accepted alternative methods and/or strategies will be available in March 2009. Following the initiatives undertaken in the pharmaceutical industry to waive the acute oral toxicity testing before going to clinical studies by using information from other in vivo studies, we proposed an approach to identify non-toxic compounds (LD50>2000mg/kg) using information from 28 days repeated dose toxicity studies. Taking into account the high prevalence of non-toxic substances (87%) in the New Chemicals Database, it was possible to set a NOAEL threshold of 200mg/kg that allowed the correct identification of 63% of non-toxic compounds, while testing of cosmetic ingredients.

  11. Observations of Blazar S5 0716+714 With Ground Based Telescopes and the Spitzer Infrared Space Telescope

    Science.gov (United States)

    Adkins, Jeffery; Lacy, M.; Morton, A.; Travagli, T.; Mulaveesala, M.; Santiago, J.; Rapp, S.; Stefaniak, L.

    2006-12-01

    The Gamma-Ray Large Area Space Telescope (GLAST) to be launched in 2007 has a proposed observing list that includes AGNs and Polars bright enough to be observed optically by amateurs and students. This observing list is maintained by the Global Telescope Network (GTN). One of our targets, S5 0716+714, was observed with the Spitzer Space Telescope MIPS and IRAC instruments and also using ground based telescopes. Observations were made in seven infrared bands with Spitzer. Additional observations made from the ground by students, amateur astronomers, and college observatories in R,V, and I were nearly simultaneous with the Spitzer observations. This data were used to construct light curves over the course of the observation and the Spectral Energy Distribution (SED) of the target using all the sources. These data were compared to models of the dust emission from the torus, synchrotron emission from the radio core, and thermal emission from the accretion disk to determine the relative importance of the different emission mechanisms in this object as a function of wavelength. Results were compared to observations of 4C 29.45 made last year. This research was supported by the Spitzer Science Center, the National Optical Astronomy Observatory, and the California Department of Education's Specialized Secondary Program.

  12. Preliminary Design of the Brazilian's National Institute for Space Research Broadband Radiometer for Solar Observations

    Science.gov (United States)

    Berni, L. A.; Vieira, L. E. A.; Savonov, G. S.; Dal Lago, A.; Mendes, O.; Silva, M. R.; Guarnieri, F.; Sampaio, M.; Barbosa, M. J.; Vilas Boas, J. V.; Branco, R. H. F.; Nishimori, M.; Silva, L. A.; Carlesso, F.; Rodríguez Gómez, J. M.; Alves, L. R.; Vaz Castilho, B.; Santos, J.; Silva Paula, A.; Cardoso, F.

    2017-10-01

    The Total Solar Irradiance (TSI), which is the total radiation arriving at Earth's atmosphere from the Sun, is one of the most important forcing of the Earths climate. Measurements of the TSI have been made employing instruments on board several space-based platforms during the last four solar cycles. However, combining these measurements is still challenging due to the degradation of the sensor elements and the long-term stability of the electronics. Here we describe the preliminary efforts to design an absolute radiometer based on the principle of electrical substitution that is under development at Brazilian's National Institute for Space Research (INPE).

  13. Tachyphylaxis associated with repeated epidural injections of lidocaine is not related to changes in distribution or the rate of elimination from the epidural space

    DEFF Research Database (Denmark)

    Mogensen, T; Simonsen, L; Scott, N B

    1989-01-01

    technetium-99m diethylenetriaminepentaacetate [99mTc-DTPA]) and elimination of lidocaine from the epidural space (as measured by serum concentrations of lidocaine) was investigated in 18 patients undergoing minor surgery during lumbar epidural analgesia. Twelve patients received four injections of 20 mL of 2......% lidocaine at 2-hr intervals. Epidural distribution was assessed by injection of 99mTc-DTPA diluted in saline on the preoperative day and diluted in an equal volume of 2% lidocaine on the morning before surgery and again after the fourth injection of lidocaine 6 hr later. The distribution of 99m......L of 2% lidocaine were injected three times at 2-hr intervals before surgery, with measurements of serum concentrations of lidocaine after the first and last injections. Despite tachyphylaxis (no patient had sensory analgesia 2 hr after the third injection), there was no difference in the rate...

  14. Hubble Space Telescope NICMOS observations of the host galaxies of powerful radio sources : Does size matter?

    NARCIS (Netherlands)

    de Vries, WH; O'Dea, CP; Barthel, PD; Fanti, C; Fanti, R; Lehnert, MD

    2000-01-01

    We present near-infrared J- and K-band imaging of a sample of powerful radio source host galaxies with the Hubble Space Telescope NICMOS2 camera. These sources have been selected on their double-lobed radio structure and include a wide range of projected radio source sizes. The largest projected

  15. Observations of the Hubble Deep Field with the Infrared Space Observatory .2. Source detection and photometry

    DEFF Research Database (Denmark)

    Goldschmidt, P.; Oliver, S.J.; Serjeant, S.B.G.

    1997-01-01

    We present positions and fluxes of point sources found in the Infrared Space Observatory (ISO) images of the Hubble Deep Field (HDF) at 6.7 and 15 mu m. We have constructed algorithmically selected 'complete' flux-limited samples of 19 sources in the 15-mu m image, and seven sources in the 6.7-mu m...

  16. Observations of the Hubble Deep Field with the Infrared Space Observatory .2. Source detection and photometry

    DEFF Research Database (Denmark)

    Goldschmidt, P.; Oliver, S.J.; Serjeant, S.B.G.;

    1997-01-01

    We present positions and fluxes of point sources found in the Infrared Space Observatory (ISO) images of the Hubble Deep Field (HDF) at 6.7 and 15 mu m. We have constructed algorithmically selected 'complete' flux-limited samples of 19 sources in the 15-mu m image, and seven sources in the 6.7-mu m...

  17. Prospects for ultrahigh-energy particle observation based on the lunar orbital LORD space experiment

    Science.gov (United States)

    Ryabov, V. A.; Chechin, V. A.; Gusev, G. A.; Maung, K. T.

    2016-08-01

    The problem of searching for highest-energy cosmic rays and neutrinos in the Universe is reviewed. Possibilities for using the radio method for detecting particles of energies above the GZK cut-off are analyzed. The method is based on the registration of coherent radio emission produced by cascades of most energetic particles in radio-transparent lunar regolith. The Luna-Resurs Orbiter space mission to be launched in the near future (2020) involves the Lunar Orbital Radio Detector (LORD). The design of the LORD space instrument and its scientific potentialities for registration of low-intense cosmic ray particle fluxes of energies above the GZK cut-off up to 1024eV are discussed. The designed LORD module (including the antenna, amplification, and data-acquisition systems) now is under construction. Exposure and capabilities of the LORD space experiment for detection of ultrahigh-energy cosmic rays and neutrinos have been compared with those for well-known current and proposed experiments. The LORD space experiment will make it possible to obtain important information on the highest-energy particles in the Universe, to verify modern models for the origin and the propagation of ultrahigh-energy cosmic rays and neutrinos.

  18. Hubble Space Telescope Wide Field Planetary Camera 2 Observations of Neptune

    Science.gov (United States)

    1995-01-01

    Two groups have recently used the Hubble Space Telescope (HST) Wide Field Planetary Camera 2 (WFPC 2) to acquire new high-resolution images of the planet Neptune. Members of the WFPC-2 Science Team, lead by John Trauger, acquired the first series of images on 27 through 29 June 1994. These were the highest resolution images of Neptune taken since the Voyager-2 flyby in August of 1989. A more comprehensive program is currently being conducted by Heidi Hammel and Wes Lockwood. These two sets of observations are providing a wealth of new information about the structure, composition, and meteorology of this distant planet's atmosphere.Neptune is currently the most distant planet from the sun, with an orbital radius of 4.5 billion kilometers (2.8 billion miles, or 30 Astronomical Units). Even though its diameter is about four times that of the Earth (49,420 vs. 12,742 km), ground-based telescopes reveal a tiny blue disk that subtends less than 1/1200 of a degree (2.3 arc-seconds). Neptune has therefore been a particularly challenging object to study from the ground because its disk is badly blurred by the Earth's atmosphere. In spite of this, ground-based astronomers had learned a great deal about this planet since its position was first predicted by John C. Adams and Urbain Leverrier in 1845. For example, they had determined that Neptune was composed primarily of hydrogen and helium gas, and that its blue color caused by the presence of trace amounts of the gas methane, which absorbs red light. They had also detected bright cloud features whose brightness changed with time, and tracked these clouds to infer a rotation period between 17 and 22 hours.When the Voyager-2 spacecraft flew past the Neptune in 1989, its instruments revealed a surprising array of meteorological phenomena, including strong winds, bright, high-altitude clouds, and two large dark spots attributed to long-lived giant storm systems. These bright clouds and dark spots were tracked as they moved

  19. Dynamics of Antarctic and Greenland ice sheets using the borehole, radio sounding and space observations

    Directory of Open Access Journals (Sweden)

    A. N. Markov

    2016-01-01

    Full Text Available Based on data of measurements in deep ice boreholes, as well as of radar and space geodetic observations in Antarctica and Greenland, a number of new features of the ice mass transport had been revealed. Note that these features do not correspond to the traditional but still hypothetical notions (ideas of the monotonous and uniform spatial changes in the ice sheet dynamics. Using results of the long-term monitoring of the borehole coordinate axes at the Vostok station (down to 1920 m, east profile Vostok – Vostok 1 – Pionerskaya – Mirny (1409 km, down to the depth of 450 m, and analysis of radar sections, Russian specialists revealed the following: a the Antarctic ice sheet has stratified changes in speed and a fan-like change in the flow direction along the depth; b plastic firn layer has individual parameters of dynamics and actually flows down from more monolithic body of the ice sheet (the flow directions differ by 30–80°; c in some places inside the sheet, the underlying ice masses flow faster than the upper ones. Researchers from the United States and Denmark registered on the radar sections of the lowest third of the ice domes in the central regions of the Antarctica (AGAP and Greenland (NEEM some folded structures, which were not typical of ice sheets (vertical amplitude of the folds is about 400 m, inclination of the wings is about 45 degrees or more. The tectonic analysis we have performed allows making a conclusion that a genesis of these ice structures is identical to the diapir folds and to diapirs which are formed at a displacement of lower plastic ice masses by the upper monolithic ones, or to echelon folds of crumpling of lower ice layers at their faster flow along original bed as compared with the overlying ice mass. This makes possible to suggest that a turbulent ice flow can occur in the spacious near-bottom and the most plastic area, and a model of the ice sheet dynamics is considered as extruding of

  20. The Observer's Ghost: a field-space connection-form and its application to gauge theories and general relativity

    CERN Document Server

    Gomes, Henrique

    2016-01-01

    We introduce a functional covariant differential as a tool for studying field space geometry in a manifestly covariant way. We then touch upon its role in gauge theories and general relativity over bounded regions, and in BRST symmetry. Due to the Gribov problem, we argue that our formalism ---allowing for a non-vanishing functional curvature---is necessary for a global treatment of gauge-invariance in field space. We conclude by suggesting that the structures we introduce satisfactorily implement the notion of a (non-asymptotic) observer in gauge theories and general relativity.

  1. Accounting for correlated observations in an age-based state-space stock assessment model

    DEFF Research Database (Denmark)

    Berg, Casper Willestofte; Nielsen, Anders

    2016-01-01

    Fish stock assessment models often relyon size- or age-specific observations that are assumed to be statistically independent of each other. In reality, these observations are not raw observations, but rather they are estimates from a catch-standardization model or similar summary statistics based...

  2. Spaces

    Directory of Open Access Journals (Sweden)

    Maziar Nekovee

    2010-01-01

    Full Text Available Cognitive radio is being intensively researched as the enabling technology for license-exempt access to the so-called TV White Spaces (TVWS, large portions of spectrum in the UHF/VHF bands which become available on a geographical basis after digital switchover. Both in the US, and more recently, in the UK the regulators have given conditional endorsement to this new mode of access. This paper reviews the state-of-the-art in technology, regulation, and standardisation of cognitive access to TVWS. It examines the spectrum opportunity and commercial use cases associated with this form of secondary access.

  3. Simulation and observation of driven beam oscillations with space charge in the CERN PS Booster

    CERN Document Server

    McAteer, M; Benedetto, E; Carli, C; Findlay, A; Mikulec, B; Tomás, R

    2014-01-01

    As part of the LHC Injector Upgrade project, the CERN PS Booster will be required to operate at nearly doubled intensity with little allowable increase in emittance growth or beam loss. A campaign of nonlinear optics measurements from turn-by-turn trajectory measurements, with the goal of characterizing and then compensating for higher-order resonances, is planned for after Long Shutdown 1. The trajectory measurement system is expected initially to require high intensity beam in order to have good position measurement resolution, so understanding space charge effects will be important for optics analysis. We present the results of simulations of driven beam oscillations with space charge effects, and comparison with trial beam trajectory measurements.

  4. Cluster spacecraft observations of a ULF wave enhanced by Space Plasma Exploration by Active Radar (SPEAR

    Directory of Open Access Journals (Sweden)

    S. V. Badman

    2009-09-01

    Full Text Available Space Plasma Exploration by Active Radar (SPEAR is a high-latitude ionospheric heating facility capable of exciting ULF waves on local magnetic field lines. We examine an interval from 1 February 2006 when SPEAR was transmitting a 1 Hz modulation signal with a 10 min on-off cycle. Ground magnetometer data indicated that SPEAR modulated currents in the local ionosphere at 1 Hz, and enhanced a natural field line resonance with a 10 min period. During this interval the Cluster spacecraft passed over the heater site. Signatures of the SPEAR-enhanced field line resonance were present in the magnetic field data measured by the magnetometer on-board Cluster-2. These are the first joint ground- and space-based detections of field line tagging by SPEAR.

  5. The Pericles Space Case: Preserving Earth Observation Data for the Future

    Science.gov (United States)

    Muller, C.; Pandey, P.; Pericles Consortium

    2016-08-01

    PERICLES (Promoting and Enhancing the Reuse of Information throughout the Content Lifecycle exploiting Evolving Semantics) is an FP7 project started on February 2013. It aims at preserving by design large and complex data sets. PERICLES is coordinated by King's College London, UK and its partners are University of Borås (Sweden), CERT (Greece), DotSoft(Greece), GeorgAugustUniversität, Göttingen (Germany), University of Liverpool (UK), Space Application Services (Belgium), XEROX France and University of Edinburgh (UK). Two additional partners provide the case studies: Tate Gallery (UK) brings the digital art and media case study and B.USOC (Belgian Users Support and Operations Centre) brings the space science case study.

  6. Exploring Extrasolar Planetary Systems: New Observations of Extrasolar Planets Enabled by the James Webb Space Telescope

    Science.gov (United States)

    Clampin, Mark

    2012-01-01

    The search for extrasolar planets has been increasingly success over the last few years. In excess of 700 systems are now known, and Kepler has approx.2500 additional candidate systems, yet to be confirmed. Recently, progress has also been made in directly imaging extrasolar planets, both from the ground and in space. In this presentation will discuss the techniques employed to discover planetary systems, and highlight the capabilities, enabled by the James Webb Space Telescope (JWST). JWST is a large 6.5 meter aperture infrared telescope that is scheduled for launch in 2018, and will allow us to transition to characterizing the properties of these extrasolar planets and the planetary systems in which they reside.

  7. Evidence for Type Ia Supernova Diversity from Ultraviolet Observations with the Hubble Space Telescope

    OpenAIRE

    Wang, Xiaofeng; Wang, Lifan; Filippenko, Alexei V.; Baron, Eddie; Kromer, Markus; Jack, Dennis; Zhang, Tianmeng,; Aldering, Greg; Antilogus, Pierre; Arnett, David; Baade, Dietrich; Barris, Brian J.; Benetti, Stefano; Bouchet, Patrice; Burrows, Adam S.

    2011-01-01

    We present ultraviolet (UV) spectroscopy and photometry of four Type Ia supernovae (SNe 2004dt, 2004ef, 2005M, and 2005cf) obtained with the UV prism of the Advanced Camera for Surveys on the Hubble Space Telescope. This dataset provides unique spectral time series down to 2000 Angstrom. Significant diversity is seen in the near maximum-light spectra (~ 2000--3500 Angstrom) for this small sample. The corresponding photometric data, together with archival data from Swift Ultraviolet/Optical Te...

  8. Prebiotic chemistry in icy grain mantles in space. An experimental and observational approach.

    Science.gov (United States)

    Muñoz Caro, Guillermo M; Dartois, Emmanuel

    2013-03-07

    A compendium of different solid carbonaceous materials detected in space is presented, focussing on the search for organic matter of prebiotic interest. This journey takes us from the carbon grains likely formed in the atmospheres of evolved stars to organic grain mantles made from ice processing thought to be present in dense interstellar clouds and circumstellar regions, making a stop in solar system objects that could have delivered organic species to the early Earth. The most abundant carbon materials detected to date in space appear to be of little biological relevance. On the other hand, organic refractory residues, made in the laboratory from UV-photoprocessing followed by warm-up of interstellar ice analogs, are a hydrocarbon material rich in O and N containing chemical compounds that could act as initiators of prebiotic chemistry. A similar material might be present in dust grains inside dense clouds or circumstellar regions, some comets, and as a minor component in carbonaceous chondrites. We use infrared spectroscopy as a tool to spot organic refractory matter in various space environments. The delivery of organic materials via comets, (micro-) meteorites, and interplanetary dust particles to the primitive Earth might have contributed as a starting material for prebiotic chemistry. To test this hypothesis, it is first essential to characterize the composition of exogenous organic matter.

  9. A Review of Nonlinear Low Frequency (LF) Wave Observations in Space Plasmas: On the Development of Plasma Turbulence

    Science.gov (United States)

    Tsurutani, Bruce T.

    1995-01-01

    As the lead-off presentation for the topic of nonlinear waves and their evolution, we will illustrate some prominent examples of waves in space plasmas. We will describe recent observations detected within planetary foreshocks, near comets and in interplanetary space. It is believed that the nonlinear LF plasma wave features discussed here are part of and may be basic to the development of plasma turbulence. In this sense, this is one area of space plasma physics that is fundamental, with applications to fusion physics and astrophysics as well. It is hoped that the reader(s) will be stimulated to study nonlinear wave development themselves, if he/she is not already involved.

  10. Space Telescope Imaging Spectrograph Observations of High-Velocity Interstellar Absorption-Line Profiles in the Carina Nebula

    Science.gov (United States)

    Walborn, Nolan R.; Danks, Anthony C.; Vieira, Gladys; Landsman, Wayne B.

    2002-06-01

    An atlas of ultraviolet interstellar absorption-line profiles toward four stars in the Carina Nebula is presented. The observations have been made with the Space Telescope Imaging Spectrograph on the Hubble Space Telescope, with a resolving power of 114,000. Low-ionization, high-ionization, and excited-state lines from a wide array of chemical species are included. Extensive measurements of radial velocities, velocity dispersions, and column densities of individual components in these profiles are also given. The unprecedented capabilities of STIS reveal many more velocity components than previously known; most of the high-velocity components in previous observations with the International Ultraviolet Explorer are now resolved into multiple subcomponents, and even higher velocities are seen. The great range of line strengths available permits the detection of the low-velocity components in the weakest lines, and progressively higher velocities in stronger lines (in which the low-velocity components become completely blended). The weak and high-ionization lines trace global structure in the H II region, while the strong low-ionization lines show intricate high-velocity structure that likely originates relatively near to the O stars observed. The extreme velocities found in the low-ionization lines toward these four stars are -388 and +127 km s-1, with 23-26 resolved components in each. Some components in different stars may be related, but many are different in each line of sight. A remarkably well-defined Routly-Spitzer effect is found in this region. Temporal variations toward one star observed twice have already been reported. These measurements will be used in subsequent astrophysical analyses to further constrain the origins of the phenomena. Based on observations with the NASA/ESA Hubble Space Telescope obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract

  11. Speech-based recognition of self-reported and observed emotion in a dimensional space

    NARCIS (Netherlands)

    Truong, Khiet P.; Leeuwen, van David A.; Jong, de Franciska M.G.

    2012-01-01

    The differences between self-reported and observed emotion have only marginally been investigated in the context of speech-based automatic emotion recognition. We address this issue by comparing self-reported emotion ratings to observed emotion ratings and look at how differences between these two t

  12. Observability and Estimation of Distributed Space Systems via Local Information-Exchange Networks

    Science.gov (United States)

    Rahmani, Amirreza; Mesbahi, Mehran; Fathpour, Nanaz; Hadaegh, Fred Y.

    2008-01-01

    In this work, we develop an approach to formation estimation by explicitly characterizing formation's system-theoretic attributes in terms of the underlying inter-spacecraft information-exchange network. In particular, we approach the formation observer/estimator design by relaxing the accessibility to the global state information by a centralized observer/estimator- and in turn- providing an analysis and synthesis framework for formation observers/estimators that rely on local measurements. The noveltyof our approach hinges upon the explicit examination of the underlying distributed spacecraft network in the realm of guidance, navigation, and control algorithmic analysis and design. The overarching goal of our general research program, some of whose results are reported in this paper, is the development of distributed spacecraft estimation algorithms that are scalable, modular, and robust to variations inthe topology and link characteristics of the formation information exchange network. In this work, we consider the observability of a spacecraft formation from a single observation node and utilize the agreement protocol as a mechanism for observing formation states from local measurements. Specifically, we show how the symmetry structure of the network, characterized in terms of its automorphism group, directly relates to the observability of the corresponding multi-agent system The ramification of this notion of observability over networks is then explored in the context of distributed formation estimation.

  13. The Nuclear Structure of 3C84 with Space VLBI (RadioAstron) Observations

    CERN Document Server

    Giovannini, Gabriele; Savolainen, Tuomas; Nagai, Hiroshi; Giroletti, Marcello; Hada, Kazuhiro; Bruni, Gabriele; Hodgson, Jeffrey; Honma, Mareki; Kino, Motoki; Kovalev, Yuri Y; Krichbaum, Thomas; Lee, Sang-Sung; Lobanov, Andrei; Sohn, Bong Won; Sokolovsky, Kirill; Voitsik, Peter; Zensus, J Anton

    2015-01-01

    The radio galaxy 3C84 is a representative of gamma-ray-bright misaligned active galactic nuclei (AGN) and one of the best laboratories to study the radio properties of subparsec scale jets. We discuss here the past and present activity of the nuclear region within the central 1pc and the properties of subparsec-sized components C1, C2 and C3. We compare these results with the high resolution space-VLBI image at 5GHz obtained with the RadioAstron satellite and we shortly discuss the possible correlation of radio emission with the gamma-ray emission.

  14. Theory and Observations of Plasma Waves Excited Space Shuttle OMS Burns in the Ionosphere

    Science.gov (United States)

    Bernhardt, P. A.; Pfaff, R. F.; Schuck, P. W.; Hunton, D. E.; Hairston, M. R.

    2010-12-01

    Measurements of artificial plasma turbulence were obtained during two Shuttle Exhaust Ionospheric Turbulence Experiments (SEITE) conducted during the flights of the Space Shuttle (STS-127 and STS-129). Based on computer modeling at the NRL PPD and Laboratory for Computational Physics & Fluid Dynamics (LCP), two dedicated burns of the Space Shuttle Orbital Maneuver Subsystem (OMS) engines were scheduled to produce 200 to 240 kg exhaust clouds that passed over the Air Force Research Laboratory (AFRL) Communications, Navigation, and Outage Forecast System (C/NOFS) satellite. This operation required the coordination by the DoD Space Test Program (STP), the NASA Flight Dynamics Officer (FDO), the C/NOFS payload operations, and the C/NOFS instrument principal investigators. The first SEITE mission used exhaust from a 12 Second OMS burn to deposit 1 Giga-Joules of energy into the upper atmosphere at a range of 230 km from C/NOFS. The burn was timed so C/NOFS could fly though the center of the exhaust cloud at a range of 87 km above the orbit of the Space Shuttle. The first SEITE experiment is important because is provided plume detection by ionospheric plasma and electric field probes for direct sampling of irregularities that can scatter radar signals. Three types of waves were detected by C/NOFS during and after the first SEITE burn. With the ignition and termination of the pair of OMS engines, whistler mode signals were recorded at C/NOFS. Six seconds after ignition, a large amplitude electromagnetic pulse reached the satellite. This has been identified as a fast magnetosonic wave propagating across magnetic field lines to reach the electric field (VEFI) sensors on the satellite. Thirty seconds after the burn, the exhaust cloud reach C/NOFS and engulfed the satellite providing very strong electric field turbulence along with enhancements in electron and ion densities. Kinetic modeling has been used to track the electric field turbulence to an unstable velocity

  15. MIC-Large Scale Magnetically Inflated Cable Structures for Space Power, Propulsion, Communications and Observational Applications

    Science.gov (United States)

    Powell, James; Maise, George; Rather, John

    2010-01-01

    A new approach for the erection of rigid large scale structures in space-MIC (Magnetically Inflated Cable)-is described. MIC structures are launched as a compact payload of superconducting cables and attached tethers. After reaching orbit, the superconducting cables are energized with electrical current. The magnet force interactions between the cables cause them to expand outwards into the final large structure. Various structural shapes and applications are described. The MIC structure can be a simple flat disc with a superconducting outer ring that supports a tether network holding a solar cell array, or it can form a curved mirror surface that concentrates light and focuses it on a smaller region-for example, a high flux solar array that generates electric power, a high temperature receiver that heats H2 propellant for high Isp propulsion, and a giant primary reflector for a telescope for astronomy and Earth surveillance. Linear dipole and quadrupole MIC structures are also possible. The linear quadrupole structure can be used for magnetic shielding against cosmic radiation for astronauts, for example. MIC could use lightweight YBCO superconducting HTS (High Temperature Superconductor) cables, that can operate with liquid N2 coolant at engineering current densities of ~105 amp/cm2. A 1 kilometer length of MIC cable would weigh only 3 metric tons, including superconductor, thermal insulations, coolant circuits, and refrigerator, and fit within a 3 cubic meter compact package for launch. Four potential MIC applications are described: Solar-thermal propulsion using H2 propellant, space based solar power generation for beaming power to Earth, a large space telescope, and solar electric generation for a manned lunar base. The first 3 applications use large MIC solar concentrating mirrors, while the 4th application uses a surface based array of solar cells on a magnetically levitated MIC structure to follow the sun. MIC space based mirrors can be very large and light

  16. Imaging of earthquake faults using small UAVs as a pathfinder for air and space observations

    Science.gov (United States)

    Donnellan, Andrea; Green, Joseph; Ansar, Adnan; Aletky, Joseph; Glasscoe, Margaret; Ben-Zion, Yehuda; Arrowsmith, J. Ramón; DeLong, Stephen B.

    2017-01-01

    Large earthquakes cause billions of dollars in damage and extensive loss of life and property. Geodetic and topographic imaging provide measurements of transient and long-term crustal deformation needed to monitor fault zones and understand earthquakes. Earthquake-induced strain and rupture characteristics are expressed in topographic features imprinted on the landscapes of fault zones. Small UAVs provide an efficient and flexible means to collect multi-angle imagery to reconstruct fine scale fault zone topography and provide surrogate data to determine requirements for and to simulate future platforms for air- and space-based multi-angle imaging.

  17. Direct space-time observation of pulse tunneling in an electromagnetic band gap

    Science.gov (United States)

    Doiron, Serge; Haché, Alain; Winful, Herbert G.

    2007-08-01

    We present space-time-resolved measurements of electromagnetic pulses tunneling through a coaxial electromagnetic band gap structure. The results show that during the tunneling process the field distribution inside the barrier is an exponentially decaying standing wave whose amplitude increases and decreases as it slowly follows the temporal evolution of the input pulse. At no time is a pulse maximum found inside the barrier, and hence the transmitted peak is not the incident peak that has propagated to the exit. The results support the quasistatic interpretation of tunneling dynamics and confirm that the group delay is not the traversal time of the input pulse peak.

  18. Quantitative Assessment of a Novel Super-Resolution Restoration Technique Using HiRISE with Navcam Images: how much Resolution Enhancement is Possible from Repeat-Pass Observations

    Science.gov (United States)

    Tao, Y.; Muller, J.-P.

    2016-06-01

    Higher spatial resolution imaging data is always desirable to the international community of planetary scientists interested in improving understanding of surface formation processes. We have previously developed a novel Super-resolution restoration (SRR) technique (Tao & Muller, 2016) using Gotcha sub-pixel matching, orthorectification, and segmented 4th order PDE-TV, called GPT SRR, which is able to restore 5 cm-12.5 cm near rover scale images (equivalent to Navcam projected FoV at a range of ≥ 5 m) from multiple 25 cm resolution NASA MRO HiRISE images. The SRR technique has been successfully applied to the rover traverses for the MER and MSL missions within the EU FP-7 PRoViDE project. These SRR results have revealed new surface information including the imaging of individual rocks (diameter ≥ 25 cm) by comparison of the original HiRISE image and rover Navcam orthorectified image mosaics. In this work, we seek evidence from processing a very large number of stereo reconstruction results from all Navcam stereo images within PRoViDE, registration and comparison with the corresponding SRR image, in order to derive a quantitative assessment on key features including rocks (diameter < 150 cm) and rover track wheel spacing. We summarise statistics from SRR-Navcam measurements and demonstrate that our unique SRR datasets will greatly support the geological and morphological analysis and monitoring of Martian surface and can also be applied to landing site selection, in order to avoid unsuitable terrain, for any future lander/rover as well as help to define future rover paths.

  19. Optical effects of space weathering in lunar crustal magnetic anomaly regions based on CE-1 observations

    Science.gov (United States)

    Li, H.; Wang, X.; Cui, J.; Fu, X.; Zhang, G.; Yao, M.; Liu, B.; Liu, J.; Li, C.; Ouyang, Z.

    2013-12-01

    The discovery of mini-magnetospheres above the lunar surface suggests that magnetic shielding could have led to anomalous space weathering (little darkening with limited reddening) in magnetic anomaly regions. Using spectral data from Chang'E 1 Imaging Interferometer (IIM) and data from Lunar Prospector's magnetometer, we instigate the relationship between lunar crustal magnetic anomalies and the optical effects in those areas in association with space weathering. The IIM onboard China's Chang'E 1 (CE-1) spacecraft is a Fourier transform Sagnac imaging spectrometer operating in the visible to near infrared (0.48-0.96 μm) spectral range, with 32 channels at spectral intervals of 325.5 cm-1. We selected four regions with crustal magnetic anomalies to study their albedo properties: three lunar swirls (Gerasimovich, Mare Marginis, and Reiner Gamma) and the area antipodal to Herzsprung. We found that all three of the anomalous albedo areas are associated with magnetic anomalies, however, no anomalous albedo feature is found in the last magnetic anomaly area. In addition, we also studied the correlation between magnetic anomaly strength and albedo anomaly on a global scale. Our initial analysis suggests an overall tread of less darkening with increased magnetic anomaly.

  20. Design and Simulation of a Fused Silica Space Cell Culture and Observation Cavity with Microfluidic and Temperature Controlling

    Directory of Open Access Journals (Sweden)

    Shangchun Fan

    2013-01-01

    Full Text Available We report a principle prototype of space animal cell perfusion culture and observation. Unlike previous work, our cell culture system cannot only realize microfluidic and temperature controlling, automatic observation, and recording but also meet an increasing cell culture at large scale operation and overcome shear force for animal cells. A key component in the system is ingenious structural fused silica cell culture cavity with the wedge-shaped connection. Finite volume method (FVM is applied to calculate its multipoint flow field, pressure field, axial velocity, tangential velocity, and radial velocity. In order to provide appropriate flow rate, temperature, and shear force for space animal cell culture, a closed-loop microfluidic circuit and proportional, integrating, and differentiation (PID algorithm are employed. This paper also illustrates system architecture and operating method of the principle prototype. The dynamic culture, autofocus observation, and recording of M763 cells are performed successfully within 72 h in the laboratory environment. This research can provide a reference for space flight mission that carries an apparatus with similar functions.

  1. PREDICTION OF CONSUMERS' INTENSION THROUGH THEIR BEHAVIOR OBSERVATION IN UBIQUITOUS SHOP SPACE

    National Research Council Canada - National Science Library

    Somkiat SAE-UENG; Sineenard PINYAPONG; Akihiro OGINO; Toshikazu KATO

    2008-01-01

    This paper has studied and observed the consumer behavior by collecting all kinds of actions of consumers and applying the ubiquitous environment which are RFID and camera sensors to gathering log data...

  2. A novel space-based observation strategy for GEO objects based on daily pointing adjustment of multi-sensors

    Science.gov (United States)

    Hu, Yun-peng; Li, Ke-bo; Xu, Wei; Chen, Lei; Huang, Jian-yu

    2016-08-01

    Space-based visible (SBV) program has been proved to be with a large advantage to observe geosynchronous earth orbit (GEO) objects. With the development of SBV observation started from 1996, many strategies have come out for the purpose of observing GEO objects more efficiently. However it is a big challenge to visit all the GEO objects in a relatively short time because of the distribution characteristics of GEO belt and limited field of view (FOV) of sensor. And it's also difficult to keep a high coverage of the GEO belt every day in a whole year. In this paper, a space-based observation strategy for GEO objects is designed based on the characteristics of the GEO belt. The mathematical formula of GEO belt is deduced and the evolvement of GEO objects is illustrated. There are basically two kinds of orientation strategies for most observation satellites, i.e., earth-oriented and inertia-directional. Influences of both strategies to their own observation regions are analyzed and compared with each other. A passive optical instrument with daily attitude-adjusting strategies is proposed to increase the daily coverage rate of GEO objects in a whole year. Furthermore, in order to observe more GEO objects in a relatively short time, the strategy of a satellite with multi-sensors is proposed. The installation parameters between different sensors are optimized, more than 98% of GEO satellites can be observed every day and almost all the GEO satellites can be observed every two days with 3 sensors (FOV: 6° × 6°) on the satellite under the strategy of daily pointing adjustment in a whole year.

  3. GOCK-2003 catalogue of positions and orbital elements of the geosynchronous space objects observed in 2003.

    Science.gov (United States)

    Kizyun, L. M.

    2004-10-01

    We describe the GOCK-2003 Catalogue (Geosynchronous Objects Catalogue: Kyiv 2003) containing topocentric equatorial coordinates and orbital elements of geosynchronous satellites obtained by photographic method at the Main Astronomical Observatory of the National Academy of Sciences of Ukraine in 2003.(http://www/mao.kiev.ua/ast/astrom.htm). Our results of the identification of 26 objects on the basis of 116 observations from among the total 173 observations of 57 objects are presented.

  4. Observations of the Hubble Deep Field with the Infrared Space Observatory .1. Data reduction, maps and sky coverage

    DEFF Research Database (Denmark)

    Serjeant, S.B.G.; Eaton, N.; Oliver, S.J.

    1997-01-01

    We present deep imaging at 6.7 and 15 mu m from the CAM instrument on the Infrared Space Observatory (ISO), centred on the Hubble Deep Field (HDF). These are the deepest integrations published to date at these wavelengths in any region of sky. We discuss the observational strategy and the data...... reduction. The observed source density appears to approach the CAM confusion limit at 15 mu m, and fluctuations in the 6.7-mu m sky background may be identifiable with similar spatial fluctuations in the HDF galaxy counts. ISO appears to be detecting comparable field galaxy populations to the HDF, and our...

  5. The 2006 SPIE Symposium on Astronomical Telescopes and Instrumentation ? Observing the Universe from Ground and Space

    Science.gov (United States)

    Moorwood, A.

    2006-06-01

    The most recent of these biennial SPIE (The International Society for Optical Engineering) Symposia was held from 24-31 May in the Orlando World Center Marriott Resort & Convention Center in Florida, USA. Over the last decade, these meetings have grown to become the main forum for presenting and discussing all aspects of ground-based, airborne and space telescopes and their instrumentation, including associated advances in technology, software, operations and even astronomical results. As a consequence the meetings are large and well attended by people at all levels in the process of initiating, approving, implementing and operating astronomical projects and facilities. This year there were ~ 1700 registered participants who presented ~ 1600 papers and posters in the following 12 parallel conferences which formed the heart of the meeting.

  6. CRBLASTER: A Fast Parallel-Processing Program for Cosmic Ray Rejection in Space-Based Observations

    Science.gov (United States)

    Mighell, K.

    Many astronomical image analysis tasks are based on algorithms that can be described as being embarrassingly parallel - where the analysis of one subimage generally does not affect the analysis of another subimage. Yet few parallel-processing astrophysical image-analysis programs exist that can easily take full advantage of today's fast multi-core servers costing a few thousands of dollars. One reason for the shortage of state-of-the-art parallel processing astrophysical image-analysis codes is that the writing of parallel codes has been perceived to be difficult. I describe a new fast parallel-processing image-analysis program called CRBLASTER which does cosmic ray rejection using van Dokkum's L.A.Cosmic algorithm. CRBLASTER is written in C using the industry standard Message Passing Interface library. Processing a single 800 x 800 Hubble Space Telescope Wide-Field Planetary Camera 2 (WFPC2) image takes 1.9 seconds using 4 processors on an Apple Xserve with two dual-core 3.0-GHz Intel Xeons; the efficiency of the program running with the 4 cores is 82%. The code has been designed to be used as a software framework for the easy development of parallel-processing image-analysis programs using embarrassing parallel algorithms; all that needs to be done is to replace the core image processing task (in this case the C function that performs the L.A.Cosmic algorithm) with an alternative image analysis task based on a single processor algorithm. I describe the design and implementation of the program and then discuss how it could possibly be used to quickly do time-critical analysis applications such as those involved with space surveillance or do complex calibration tasks as part of the pipeline processing of images from large focal plane arrays.

  7. The effect of sensor resolution on the number of cloud-free observations from space

    Directory of Open Access Journals (Sweden)

    J. M. Krijger

    2006-06-01

    Full Text Available Air quality and surface emission inversions are likely to be focal points for future satellite missions on atmospheric composition. Most important for these applications is sensitivity to the atmospheric composition in the lowest few kilometers of the troposphere. Reduced sensitivity by clouds needs to be minimized. In this study we have quantified the increase in number of useful footprints, i.e. footprints which are sufficient cloud-free, as a function of sensor resolution (footprint area. High resolution (1 km×1 km MODIS TERRA cloud mask observations are aggregated to lower resolutions. Statistics for different thresholds on cloudiness are applied. For each month in 2004 two days of MODIS data are analyzed. Globally the fraction of cloud-free observations drops from 16% at 100 km2 resolution to only 3% at 10 000 km2 if not a single MODIS observation within a footprint is allowed to be cloudy. If up to 5% or 20% of a footprint is allowed to be cloudy, the fraction of cloud-free observations is 9% or 17%, respectively, at 10 000 km2 resolution. The probability of finding cloud-free observations for different sensor resolutions is also quantified as a function of geolocation and season, showing examples over Europe and northern South America.

  8. Squeezed bispectrum in the δ N formalism: local observer effect in field space

    Science.gov (United States)

    Tada, Yuichiro; Vennin, Vincent

    2017-02-01

    The prospects of future galaxy surveys for non-Gaussianity measurements call for the development of robust techniques for computing the bispectrum of primordial cosmological perturbations. In this paper, we propose a novel approach to the calculation of the squeezed bispectrum in multiple-field inflation. With use of the δ N formalism, our framework sheds new light on the recently pointed out difference between the squeezed bispectrum for global observers and that for local observers, while allowing one to calculate both. For local observers in particular, the squeezed bispectrum is found to vanish in single-field inflation. Furthermore, our framework allows one to go beyond the near-equilateral ("small hierarchy") limit, and to automatically include intrinsic non-Gaussianities that do not need to be calculated separately. The explicit computational programme of our method is given and illustrated with a few examples.

  9. Visual astronomy under dark skies a new approach to observing deep space

    CERN Document Server

    Cooke, Antony

    2005-01-01

    Modern astronomical telescopes, along with other advances in technology, have brought the deep sky - star clusters, nebulae and the galaxies - within reach of amateur astronomers. And it isn't even necessary to image many of these deep-sky objects in order to see them; they are within reach of visual observers using modern techniques and enhancement technology. The first requirement is truly dark skies; if you are observing from a light-polluted environment you need Tony Cooke's book, Visual Astronomy in the Suburbs. Given a site with clear, dark night skies everything else follows… this book will provide the reader with everything he needs to know about what to observe, and using some of today's state-of-the-art technique and commercial equipment, how to get superb views of faint and distant astronomical objects.

  10. Squeezed Bispectrum in the $\\delta N$ Formalism: Local Observer Effect in Field Space

    CERN Document Server

    Tada, Yuichiro

    2016-01-01

    The prospects of future galaxy surveys for non-Gaussianity measurements call for the development of robust techniques for computing the bispectrum of primordial cosmological perturbations. In this paper, we propose a novel approach to the calculation of the squeezed bispectrum in multiple-field inflation. With use of the $\\delta N$ formalism, our framework sheds new light on the recently pointed out difference between the squeezed bispectrum for global observers and that for local observers, while allowing one to calculate both. For local observers in particular, the squeezed bispectrum is found to vanish in single-field inflation. Furthermore, our framework allows one to go beyond the near-equilateral ("small hierarchy") limit, and to automatically include intrinsic non-Gaussianities that do not need to be calculated separately. The explicit computational programme of our method is given and illustrated with a few examples.

  11. Comparison of Precipitation Observations from a Prototype Space-based Cloud Radar and Ground-based Radars

    Institute of Scientific and Technical Information of China (English)

    LIU Liping; ZHANG Zhiqiang; YU Danru; YANG Hu; ZHAO Chonghui; ZHONG Lingzhi

    2012-01-01

    A prototype space-based cloud radar has been developed and was installed on an airplane to observe a precipitation system over Tianjin,China in July 2010.Ground-based S-band and Ka-band radars were used to examine the observational capability of the prototype. A cross-comparison algorithm between different wavelengths,spatial resolutions and platform radars is presented.The reflectivity biases,correlation coefficients and standard deviations between the radars are analyzed.The equivalent reflectivity bias between the S- and Ka-band radars were simulated with a given raindrop size distribution.The results indicated that reflectivity bias between the S- and Ka-band radars due to scattering properties was less than 5 dB,and for weak precipitation the bias was negligible. The prototype space-based cloud radar was able to measure a reasonable vertical profile of reflectivity,but the reflectivity below an altitude of 1.5 km above ground level was obscured by ground clutter.The measured reflectivity by the prototype space-based cloud radar was approximately 10.9 dB stronger than that by the S-band Doppler radar (SA radar),and 13.7 dB stronger than that by the ground-based cloud radar.The reflectivity measured by the SA radar was 0.4 dB stronger than that by the ground-based cloud radar.This study could provide a method for the quantitative examination of the observation ability for space-based radars.

  12. Observation

    Science.gov (United States)

    Patell, Hilla

    2016-01-01

    In order to achieve the goal of observation, preparation of the adult, the observer, is necessary. This preparation, says Hilla Patell, requires us to "have an appreciation of the significance of the child's spontaneous activities and a more thorough understanding of the child's needs." She discusses the growth of both the desire to…

  13. Observation

    Science.gov (United States)

    Kripalani, Lakshmi A.

    2016-01-01

    The adult who is inexperienced in the art of observation may, even with the best intentions, react to a child's behavior in a way that hinders instead of helping the child's development. Kripalani outlines the need for training and practice in observation in order to "understand the needs of the children and...to understand how to remove…

  14. A Theoretic Model for the Shock Observed in Geo-space

    Institute of Scientific and Technical Information of China (English)

    SHI Jian-Kui; WANG Xiao; ZHANG Tie-Long; Torkar Klaus; LIU Zhen-Xing

    2005-01-01

    An electrostatic model for the shock observed in the earth's polar region is established by deriving the "Sagdeev potential" from the magnetohydrodynamic equations in a cylindrical coordinate system. The results show that the shock can develop from the ion acoustic wave or ion cyclotron wave. in the polar region, and can exist when the Mach number M and the initial electric field E0 satisfy the condition of |(a/M2 - 1) E0| = 1. Also, some features of the shock wave are discussed. The result can interpret the electrostatic shock observed in the earth's polar region.

  15. Can we monitor groundwater head variation from space? Coupling ERS spaceborne microwave observations to groundwater dynamics

    NARCIS (Netherlands)

    Sutanudjaja, E. H.; de Jong, S. M.; van Geer, F. C.; Bierkens, M. F. P.

    2012-01-01

    The objective of this study is to investigate whether the time series of a remote sensing based soil moisture product, referred as the European Remote Sensing Soil Water Index (ERS SWI), correlates to in-situ observations of groundwater heads; and can thus be used for groundwater head prediction. As

  16. FIREBall-2: Trailblazing observations of the space UV circumgalactic medium (Columbia University, Co-I Proposal)

    Science.gov (United States)

    Schiminovich, David

    ). Additional funding is necessary to keep this highly qualified balloon team together for a second flight. FIREBall-2 will test key technologies and science strategies for a future space mission to map emission from CGM and IGM baryons. Its flights will continue to provide important training for the next generation of space astrophysicists working in UV and other wavelength instrumentation. Most importantly, FIREBall-2 will detect emission from the CGM of nearby galaxies, providing the first census of the density and kinematics of this material for low z galaxies and open-ing a new field of CGM science.

  17. Prospective Register Of patients undergoing repeated OFfice and Ambulatory Blood Pressure Monitoring (PROOF-ABPM): protocol for an observational cohort study.

    Science.gov (United States)

    Sheppard, James P; Martin, Una; Gill, Paramjit; Stevens, Richard; McManus, Richard J

    2016-10-31

    The diagnosis and management of hypertension depends on accurate measurement of blood pressure (BP) in order to target antihypertensive treatment appropriately. Most BP measurements take place in a clinic setting, but it has long been recognised that readings taken out-of-office (via home or ambulatory monitoring) estimate true underlying BP more accurately. Recent studies have shown that the change in clinic BP over multiple readings is a significant predictor of the difference between clinic and out-of-office BP. Used in combination with patient characteristics, this change has been shown to accurately predict a patient's out-of-office BP level. The present study proposes to collect real-life BP data to prospectively validate this new prediction tool in routine clinical practice. A prospective, multicentre observational cohort design will be used, recruiting patients from primary and secondary care. All patients attending participating centres for ambulatory BP monitoring will be eligible to participate. Anonymised clinical data will be collected from all eligible patients, who will be invited to give informed consent to permit identifiable data to be collected for data linkage to external outcome registries. Descriptive statistics will be used to calculate the sensitivity, specificity, positive and negative predictive values of the out-of-office BP prediction tool. Area under the receiver operator characteristic curve statistics will be used to examine model performance. Ethical approval for this study has been obtained from the National Research. Ethics Service Committee South Central-Oxford A (reference; 15/SC/0184), and site-specific R&D approval has been acquired from the relevant NHS trusts. All findings will be presented at relevant conferences and published in peer-reviewed journals, on the study website and disseminated in lay and social media where appropriate. Published by the BMJ Publishing Group Limited. For permission to use (where not already

  18. Knot a Bad Idea: Testing BLISS Mapping for Spitzer Space Telescope Eclipse Observations

    CERN Document Server

    Schwartz, Joel C

    2016-01-01

    [Abridged] Much of transiting exoplanet science relies on high-precision photometry. The current generation of instruments exhibit sensitivity variations greater than the astrophysical signals. For the InfraRed Array Camera (IRAC) on the Spitzer Space Telescope, a popular way to handle this is BiLinearly-Interpolated Subpixel Sensitivity mapping (BLISS). We use examples of posterior probability functions to show that this scheme can misfit or bias astrophysical parameters, and a toy model to show that underestimated uncertainties may even happen in very simple cases. BLISS maps of detector sensitivity can also be unreliable if the noise in the data is low. To know the astrophysical and detector models a priori, we construct a model of \\emph{Spitzer} light curves with $\\sim10^{3}$ data. We compare standard BLISS to a variant in which the knot values are full-fledged parameters in the MCMC, and to a standard polynomial model. Both types of BLISS fit the eclipse depth similarly, and the standard BLISS knots vary...

  19. Hubble Space Telescope Observations of cD Galaxies and their Globular Cluster Systems

    CERN Document Server

    Jordan, A; West, M J; Marzke, R O; Minniti, D; Rejkuba, M; Jordan, Andres; Cote, Patrick; West, Michael J.; Marzke, Ronald O.; Minniti, Dante; Rejkuba, Marina

    2004-01-01

    We have used WFPC2 on the Hubble Space Telescope to obtain F450W and F814W images of four cD galaxies (NGC 541 in Abell 194, NGC 2832 in Abell 779, NGC 4839 in Abell 1656 and NGC 7768 in Abell 2666) in the range 5400 < cz < 8100 km s^{-1}. For NGC 541, the HST data are supplemented by ground-based B and I images obtained with the FORS1 on the VLT. We present surface brightness and color profiles for each of the four galaxies, confirming their classification as cD galaxies. Isophotal analyses reveal the presence of subarcsecond-scale dust disks in the nuclei of NGC 541 and NGC 7768. Despite the extreme nature of these galaxies in terms of spatial extent and luminosity, our analysis of their globular cluster systems reveals no anomalies in terms of specific frequencies, metallicity gradients, average metallicities, or the metallicity offset between the globulars and the host galaxy. We show that the latter offset appears roughly constant at \\Delta [Fe/H] ~ 0.8 dex for early-type galaxies spanning a lumino...

  20. Cloud Structure of Galactic OB Cluster Forming Regions from Combining Ground and Space Based Bolometric Observations

    CERN Document Server

    Lin, Yuxin; Li, Di; Zhang, Zhiyu; Ginsburg, Adam; Pineda, Jaime E; Qian, Lei; Galván-Madrid, Roberto; McLeod, Anna Faye; Rosolowsky, Erik; Dale, James E; Immer, Katharina; Koch, Eric; Longmore, Steve; Walker, Daniel; Testi, Leonardo

    2016-01-01

    We have developed an iterative procedure to systematically combine the millimeter and submillimeter images of OB cluster-forming molecular clouds, which were taken by ground based (CSO, JCMT, APEX, IRAM-30m) and space telescopes (Herschel, Planck). For the seven luminous ($L$$>$10$^{6}$ $L_{\\odot}$) Galactic OB cluster-forming molecular clouds selected for our analyses, namely W49A, W43-Main, W43-South, W33, G10.6-0.4, G10.2-0.3, G10.3-0.1, we have performed single-component, modified black-body fits to each pixel of the combined (sub)millimeter images, and the Herschel PACS and SPIRE images at shorter wavelengths. The $\\sim$10$"$ resolution dust column density and temperature maps of these sources revealed dramatically different morphologies, indicating very different modes of OB cluster-formation, or parent molecular cloud structures in different evolutionary stages. The molecular clouds W49A, W33, and G10.6-0.4 show centrally concentrated massive molecular clumps that are connected with approximately radia...

  1. Observation of dynamic atom-atom correlation in liquid helium in real space.

    Science.gov (United States)

    Dmowski, W; Diallo, S O; Lokshin, K; Ehlers, G; Ferré, G; Boronat, J; Egami, T

    2017-05-04

    Liquid (4)He becomes superfluid and flows without resistance below temperature 2.17 K. Superfluidity has been a subject of intense studies and notable advances were made in elucidating the phenomenon by experiment and theory. Nevertheless, details of the microscopic state, including dynamic atom-atom correlations in the superfluid state, are not fully understood. Here using a technique of neutron dynamic pair-density function (DPDF) analysis we show that (4)He atoms in the Bose-Einstein condensate have environment significantly different from uncondensed atoms, with the interatomic distance larger than the average by about 10%, whereas the average structure changes little through the superfluid transition. DPDF peak not seen in the snap-shot pair-density function is found at 2.3 Å, and is interpreted in terms of atomic tunnelling. The real space picture of dynamic atom-atom correlations presented here reveal characteristics of atomic dynamics not recognized so far, compelling yet another look at the phenomenon.

  2. Space Technology 5 (ST-5) Observations of Field-Aligned Currents: Temporal Variability

    Science.gov (United States)

    Le, Guan

    2010-01-01

    Space Technology 5 (ST-5) is a three micro-satellite constellation deployed into a 300 x 4500 km, dawn-dusk, sun-synchronous polar orbit from March 22 to June 21, 2006, for technology validations. In this paper, we present a study of the temporal variability of field-aligned currents using multi-point magnetic field measurements from STS. The data demonstrate that masoscale current structures are commonly embedded within large-scale field-aligned current sheets. The meso-scale current structures are very dynamic with highly variable current density and/or polarity in time scales of about 10 min. They exhibit large temporal variations during both quiet and disturbed times in such time scales. On the other hand, the data also shown that the time scales for the currents to be relatively stable are about I min for meso-scale currents and about 10 min for large scale current sheets. These temporal features are obviously associated with dynamic variations of their particle carriers (mainly electrons) as they respond to the variations of the parallel electric field in auroral acceleration region. The characteristic time scales for the temporal variability of meso-scale field-aligned currents are found to be consistent with those of auroral parallel electric field.

  3. Space Technology 5 Multi-Point Observations of Temporal Variability of Field-Aligned Currents

    Science.gov (United States)

    Le, Guan; Wang, Yongli; Slavin, James A.; Strangeway, Robert J.

    2008-01-01

    Space Technology 5 (ST5) is a three micro-satellite constellation deployed into a 300 x 4500 km, dawn-dusk, sun-synchronous polar orbit from March 22 to June 21, 2006, for technology validations. In this paper, we present a study of the temporal variability of field-aligned currents using multi-point magnetic field measurements from ST5. The data demonstrate that meso-scale current structures are commonly embedded within large-scale field-aligned current sheets. The meso-scale current structures are very dynamic with highly variable current density and/or polarity in time scales of approximately 10 min. They exhibit large temporal variations during both quiet and disturbed times in such time scales. On the other hand, the data also shown that the time scales for the currents to be relatively stable are approximately 1 min for meso-scale currents and approximately 10 min for large scale current sheets. These temporal features are obviously associated with dynamic variations of their particle carriers (mainly electrons) as they respond to the variations of the parallel electric field in auroral acceleration region. The characteristic time scales for the temporal variability of meso-scale field-aligned currents are found to be consistent with those of auroral parallel electric field.

  4. Hubble Space Telescope Observations of M32 The Color-Magnitude Diagram

    CERN Document Server

    Grillmair, C J; Worthey, G; Faber, S M; Freedman, W L; Madore, B F; Ajhar, E A; Baum, W A; Holtzmann, J A; Lynds, C R; O'Neil, E J; Stetson, P B; Grillmair, Carl J.; Lauer, Tod R.; Worthey, Guy; Freedman, Wendy L.; Madore, Barry F.; Ajhar, Edward A.; Baum, William A.; Holtzman, Jon A.; Neil, Earl J. O'; Stetson, Peter B.

    1996-01-01

    We present a V-I color-magnitude diagram for a region 1'-2' from the center of M32 based on Hubble Space Telescope WFPC2 images. The broad color-luminosity distribution of red giants shows that the stellar population comprises stars with a wide range in metallicity. This distribution cannot be explained by a spread in age. The blue side of the giant branch rises to M_I ~ -4.0 and can be fitted with isochrones having [Fe/H] ~ -1.5. The red side consists of a heavily populated and dominant sequence that tops out at M_I ~ -3.2, and extends beyond V-I=4. This sequence can be fitted with isochrones with -0.2 < [Fe/H] < +0.1, for ages running from 15 Gyr to 5 Gyr respectively. We do not find the optically bright asymptotic giant branch stars seen in previous ground-based work and argue that the majority of them were artifacts of crowding. Our results are consistent with the presence of the infrared-luminous giants found in ground-based studies, though their existence cannot be directly confirmed by our data. ...

  5. Second Epoch Hubble Space Telescope Observations of Kepler's Supernova Remnant: The Proper Motions of Balmer Filaments

    CERN Document Server

    Sankrit, Ravi; Blair, William P; Long, Knox S; Williams, Brian J; Borkowski, Kazimierz J; Patnaude, Daniel J; Reynolds, Stephen P

    2015-01-01

    We report on the proper motions of Balmer-dominated filaments in Kepler's supernova remnant using high resolution images obtained with the Hubble Space Telescope at two epochs separated by about 10 years. We use the improved proper motion measurements and revised values of shock velocities to derive a distance to Kepler of 5.1 [+0.8, -0.7] kpc. The main shock around the northern rim of the remnant has a typical speed of 1690 km/s and is encountering material with densities of about 8 cm^-3. We find evidence for the variation of shock properties over small spatial scales, including differences in the driving pressures as the shock wraps around a curved cloud surface. We find that the Balmer filaments ahead of the ejecta knot on the northwest boundary of the remnant are becoming fainter and more diffuse. We also find that the Balmer filaments associated with circumstellar material in the interior regions of the remnant are due to shocks with significantly lower velocities and that the brightness variations amon...

  6. Observations of the Hubble Deep Field with the Infrared Space Observatory; 2, Source detection and photometry

    CERN Document Server

    Goldschmidt, P

    1997-01-01

    We present positions and fluxes of point sources found in the Infrared Space Observatory (ISO) images of the Hubble Deep Field (HDF) at 6.7 and 15 micron. We have constructed algorithmically selected ``complete'' flux-limited samples of 19 sources in the 15 micron image, and 7 sources in the 6.7 micron image. The typical flux limit at 15 micron is 0.2 mJy and at 6.7 micron is 0.04 mJy. We have selected ``supplementary'' samples of 3 sources at 15 micron and 20 sources at 6.7 micron by eye. We discuss the completeness and reliability of the connected pixel source detect ion algorithm used, by comparing the intrinsic and estimated properties of simulated data, and also by estimating the noise properties of the real data. The most pessimistic estimate of the number of spurious sources in the ``complete'' samples is 1 at 15 micron and 2 at 6.7 micron, and in the ``supplementary'' lists is 1 at 15 micron and 5 at 6.7 micron.

  7. Hubble Space Telescope observations of the host galaxies and environments of calcium-rich supernovae

    CERN Document Server

    Lyman, J D; James, P A; Angus, C R; Church, R P; Davies, M B; Tanvir, N R

    2016-01-01

    Calcium-rich supernovae represent a significant challenge for our understanding of the fates of stellar systems. They are less luminous than other supernova (SN) types and they evolve more rapidly to reveal nebular spectra dominated by strong calcium lines with weak or absent signatures of other intermediate- and iron-group elements, which are seen in other SNe. Strikingly, their explosion sites also mark them out as distinct from other SN types. Their galactocentric offset distribution is strongly skewed to very large offsets (around one third are offset greater than 20 kpc), meaning they do not trace the stellar light of their hosts. Many of the suggestions to explain this extreme offset distribution have invoked the necessity for unusual formation sites such as globular clusters or dwarf satellite galaxies, which are therefore difficult to detect. Building on previous work attempting to detect host systems of nearby Ca-rich SNe, we here present Hubble Space Telescope imaging of 5 members of the class - 3 e...

  8. Precipitation of radiation belt electrons by EMIC waves, observed from ground and space

    Energy Technology Data Exchange (ETDEWEB)

    Jordanova, Vania K [Los Alamos National Laboratory; Miyoski, Y [NAGOYA UNIV; Sakaguchi, K [NAGOYA UNIV; Shiokawa, K [NAGOYA UNIV; Evans, D S [NOAA, BOULDER; Albert, Jay [AFRL; Connors, M [UNIV OF ATHABASCA

    2008-01-01

    We show evidence that left-hand polarised electromagnetic ion cyclotron (EMIC) plasma waves can cause the loss of relativistic electrons into the atmosphere. Our unique set of ground and satellite observations shows coincident precipitation of ions with energies of tens of keY and of relativistic electrons into an isolated proton aurora. The coincident precipitation was produced by wave-particle interactions with EMIC waves near the plasmapause. The estimation of pitch angle diffusion coefficients supports that the observed EMIC waves caused coincident precipitation ofboth ions and relativistic electrons. This study clarifies that ions with energies of tens of ke V affect the evolution of relativistic electrons in the radiation belts via cyclotron resonance with EMIC waves, an effect that was first theoretically predicted in the early 1970's.

  9. Exploring the full parameter space for an interacting dark energy model with recent observations including redshift-space distortions: application of the parametrized post-Friedmann approach

    CERN Document Server

    Li, Yun-He; Zhang, Xin

    2014-01-01

    Dark energy can modify the dynamics of dark matter if there exists a direct interaction between them. Thus a measurement of the structure growth, e.g., redshift-space distortions (RSD), can be a powerful tool to constrain the interacting dark energy (IDE) models. For the widely studied $Q=3\\beta H\\rho_{de}$ model, previous works showed that only a very small coupling ($\\beta\\sim\\mathcal{O}(10^{-3})$) can survive in current RSD data. However, all these analyses have to assume $w>-1$ and $\\beta>0$ due to the existence of the large-scale instability in the IDE scenario. In our recent work [Phys.\\ Rev.\\ D {\\bf 90}, 063005 (2014)], we successfully solved this large-scale instability problem by establishing a parametrized post-Friedmann (PPF) framework for the IDE scenario. So we, for the first time, have the ability to explore the full parameter space of the IDE models. In this work, we reexamine the observational constraints on the $Q=3\\beta H\\rho_{de}$ model within the PPF framework. By using the Planck data, th...

  10. Constraining the Size of the Dark Region Around the M87 Black Hole by Space-VLBI Observations

    Science.gov (United States)

    Takahashi, Rohta; Mineshige, Shin

    2011-03-01

    In order to examine if the next-generation space very long baseline interferometer (VLBI), such as VSOP-2 (VLBI Space Observatory Programme-2), will make it possible to obtain direct images of the accretion flow around the M87 black hole, we calculate the expected observed images by relativistic ray-tracing simulations under considerations of possible observational errors. We consider various cases of electron temperature profiles, as well various values for the distance, mass, and spin of the M87 black hole. We find it feasible to detect an asymmetric intensity profile around the black hole caused by rapid disk rotation, as long as the electron temperature does not rise steeply toward the black hole, as was predicted by the accretion disk theory and three-dimensional magnetohydrodynamic simulations. Further, we can detect a deficit in the observed intensity around the black hole when the apparent size of the gravitational radius is larger than gsim1.5 μas. In the cases that the inner edge of the disk is located at the radius of the innermost stable circular orbit (ISCO), moreover, even the black hole spin will be measured. We also estimate the required signal-to-noise ratio {R}_SN for achieving the scientific goals mentioned above, finding that it should be at least 10 at 22 GHz. To conclude, direct mapping observations by the next-generation space VLBI will provide us a unique opportunity to provide the best evidence for the presence of a black hole and to test the accretion disk theory.

  11. GlobPermafrost- How Space-BasedEarth Observation Supports Understanding of Permafrost

    Science.gov (United States)

    Bartsch, Annett; Grosse, Guido; Kaab, Andreas; Westermann, Sebastian; Strozzi, Tazio; Wiesmann, Andreas; Duguay, Claude; Seifert, Frank Martin; Obu, Jaroslav; Goler, Robert

    2016-08-01

    The GlobPermafrost project develops, validates and implements Earth Observation (EO) products to support research communities and international organisations in their work on better understanding permafrost characteristics and dynamics. To facilitate usability of these products by the target audience, user requirements with respect to the planned products have been requested and collected through an online community survey as well as by interview. This paper provides an overview on the planned thematic EO products as well as results of the user requirement survey.

  12. Monitoring the evolution of coastal zones under various forcing factors using space-based observing systems

    OpenAIRE

    Cazenave, Anny; Benveniste, Jérôme; Champollion, Nicolas; Cozannet, Gonéri Le; Woodworth, Philip; Ablain, Michael; Becker, Mélanie; Ciccarelli, Silvia; Jevrejeva, Svetlana; Leornardi, Nicoletta; Loisel, Hubert; Long, Nathalie; Maisongrande, Philippe; Mallet, Cyril; Marcos, Marta

    2017-01-01

    International audience; About 10% of the global population is currently livingalong the coasts. In many regions, populations are exposed to a variety of natural hazards (e.g., extreme weather such as damaging cyclones and their associated storm surges), as well as to the effects of global climate change (e.g., sea level rise), and to the impacts of human activities (e.g., urbanization). Today, our knowledge regarding these processes still remains limited by the lack of observations. For examp...

  13. Technology for monitoring global change. [NASA Technology Initiative for space based observations of Earth

    Science.gov (United States)

    Johnston, Gordon I.; Hudson, Wayne R.

    1989-01-01

    Multiinstrumented earth-science platforms currently being planned for both LEO and GEO positions will furnish data for the compilation of systematic and intercorrelated information that is suitable for the treatment of interdisciplinary questions concerning atmospheric, oceanic, hydrological, geological, and biological changes of an either natural or anthropogenic nature. Attention will be given in these observational campaigns to such essential earth variables as atmospheric pressure, rainfall/snowfall, vegetation cover, soil nutrient cycles, sea surface temperatures, ocean circulation, and ocean biological productivity.

  14. Towards soil property retrieval from space: Proof of concept using in situ observations

    Science.gov (United States)

    Bandara, Ranmalee; Walker, Jeffrey P.; Rüdiger, Christoph

    2014-05-01

    Soil moisture is a key variable that controls the exchange of water and energy fluxes between the land surface and the atmosphere. However, the temporal evolution of soil moisture is neither easy to measure nor monitor at large scales because of its high spatial variability. This is mainly a result of the local variation in soil properties and vegetation cover. Thus, land surface models are normally used to predict the evolution of soil moisture and yet, despite their importance, these models are based on low-resolution soil property information or typical values. Therefore, the availability of more accurate and detailed soil parameter data than are currently available is vital, if regional or global soil moisture predictions are to be made with the accuracy required for environmental applications. The proposed solution is to estimate the soil hydraulic properties via model calibration to remotely sensed soil moisture observation, with in situ observations used as a proxy in this proof of concept study. Consequently, the feasibility is assessed, and the level of accuracy that can be expected determined, for soil hydraulic property estimation of duplex soil profiles in a semi-arid environment using near-surface soil moisture observations under naturally occurring conditions. The retrieved soil hydraulic parameters were then assessed by their reliability to predict the root zone soil moisture using the Joint UK Land Environment Simulator model. When using parameters that were retrieved using soil moisture observations, the root zone soil moisture was predicted to within an accuracy of 0.04 m3/m3, which is an improvement of ∼0.025 m3/m3 on predictions that used published values or pedo-transfer functions.

  15. Multiple Asteroid Systems: Dimensions and Thermal Properties from Spitzer Space Telescope and Ground-Based Observations

    CERN Document Server

    Marchis, F; Emery, J P; Mueller, M; Baek, M; Pollock, J; Assafin, M; Martins, R Vieira; Berthier, J; Vachier, F; Cruikshank, D P; Lim, L; Reichart, D; Ivarsen, K; Haislip, J; LaCluyz, A

    2016-01-01

    Photometric lightcurves were also obtained for 14 of them during the Spitzer observations to provide the context of the observations and reliable estimates of their absolute magnitudes. The extracted mid-IR spectra were analyzed using a modified standard thermal model (STM) and a thermophysical model (TPM) that takes into account the shape and geometry of the large primary at the time of the Spitzer observation. We derived a reliable estimate of the size, albedo, and beaming factor for each of these asteroids, representing three main taxonomic groups: C, S, and X. For large (volume-equivalent system diameter Deq $\\lt$ 130 km) binary asteroids, the TPM analysis indicates a low thermal inertia ($\\Gamma$ < $\\sim$100 J s-1/2K-1m-2) and their emissivity spectra display strong mineral features, implying that they are covered with a thick layer of thermally insulating regolith. The smaller (surface-equivalent system diameter Deff $\\lt$17 km) asteroids also show some emission lines of minerals, but they are signif...

  16. The Supersymmetric Parameter Space in Light of B-physics Observables and Electroweak Precision Data

    CERN Document Server

    Ellis, Jonathan Richard; Olive, K A; Weber, A M; Weiglein, G

    2007-01-01

    Indirect information about the possible scale of supersymmetry (SUSY) breaking is provided by B-physics observables (BPO) as well as electroweak precision observables (EWPO). We combine the constraints imposed by recent measurements of the BPO BR(b -> s gamma), BR(B_s -> mu^+ mu^-), BR(B_u -> tau nu_tau) and Delta M_{B_s} with those obtained from the experimental measurements of the EWPO M_W, sin^2 theta_eff, Gamma_Z, (g-2)_mu and M_h, incorporating the latest theoretical calculations of these observables within the Standard Model and supersymmetric extensions. We perform a chi^2 fit to the parameters of the constrained minimal supersymmetric extension of the Standard Model (CMSSM), in which the SUSY-breaking parameters are universal at the GUT scale, and the non-universal Higgs model (NUHM), in which this constraint is relaxed for the soft SUSY-breaking contributions to the Higgs masses. Assuming that the lightest supersymmetric particle (LSP) provides the cold dark matter density preferred by WMAP and other...

  17. Tropospheric methanol observations from space: constraints on the seasonality of biogenic emissions

    Science.gov (United States)

    Wells, K. C.; Millet, D. B.; Cady-Pereira, K. E.; Shephard, M. W.; Xiao, Y.; Razavi, A.; Clerbaux, C.

    2011-12-01

    Methanol is the most abundant non-methane organic compound in the atmosphere, and is an important precursor of atmospheric pollutants such as CO and formaldehyde. The recent development of methanol retrievals from nadir-viewing satellite-based platforms offers powerful new information for quantifying methanol emissions on a global scale. This study uses methanol observations from the Tropospheric Emission Spectrometer (TES) on the Aura satellite and the Infrared Atmospheric Sounding Interferometer (IASI) on the MetOp-A satellite, in conjunction with aircraft data, to investigate methanol emissions from major plant functional types in the GEOS-Chem global chemical transport model (driven with MEGAN biogenic emissions). We first evaluate the TES methanol retrievals by comparing to simulation results and flight observations from several North American field campaigns. Results show that the retrieval performs well when the degrees of freedom for signal are above 0.5. We analyze one full year of TES and IASI observations and find a persistent model underestimate in springtime, and make recommendations for an improved seasonal distribution of biogenic methanol emissions over temperate regions of the globe.

  18. Diurnal variation of oxygen isotopic enrichment in asymmetric-18 ozone observed by the SMILES from space

    Science.gov (United States)

    Sato, T. O.; Kuribayashi, K.; Yoshida, N.; Kasai, Y.

    2017-06-01

    Atomic oxygen is a key oxidant for greenhouse gases such as H2O, CH4, and N2O whose amounts are currently increasing in the stratosphere. Ozone photolysis is a major source of atomic oxygen generation. We found, for the first time, that the ozone photolysis of 48O3 and 18O16O16O generated a sharp diurnal variation of δ18OOO in the middle stratosphere (37 km), in contrast to the temporal variation of 48O3. The average isotopic enrichment δ18OOO derived from the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) observation was higher during daytime (16.2 ± 3.3%) than at night (13.7 ± 3.6%). Isotopic fractionation effects were simulated for both ozone formation reaction and ozone photolysis with the ozone photolysis contribution estimated to be 80% of the daytime δ18OOO enhancement. Significant solar radiation dependence was observed in the isotopic fractionation of ozone photolysis derived from the SMILES observation and theoretical calculations. These results show that δ18O can be a powerful tool to investigate oxidant chemistry.

  19. Direct space-based observations of anthropogenic CO2 emission areas from OCO-2

    Science.gov (United States)

    Hakkarainen, J.; Ialongo, I.; Tamminen, J.

    2016-11-01

    Anthropogenic CO2 emissions from fossil fuel combustion have large impacts on climate. In order to monitor the increasing CO2 concentrations in the atmosphere, accurate spaceborne observations—as available from the Orbiting Carbon Observatory-2 (OCO-2)—are needed. This work provides the first direct observation of anthropogenic CO2 from OCO-2 over the main pollution regions: eastern USA, central Europe, and East Asia. This is achieved by deseasonalizing and detrending OCO-2 CO2 observations to derive CO2 anomalies. Several small isolated emission areas (such as large cities) are detectable from the anomaly maps. The spatial distribution of the CO2 anomaly matches the features observed in the maps of the Ozone Monitoring Instrument NO2 tropospheric columns, used as an indicator of atmospheric pollution. The results of a cluster analysis confirm the spatial correlation between CO2 and NO2 data over areas with different amounts of pollution. We found positive correlation between CO2 anomalies and emission inventories. The results demonstrate the power of spaceborne data for monitoring anthropogenic CO2 emissions.

  20. Cryogenically cooled low-noise amplifier for radio-astronomical observations and centimeter-wave deep-space communications systems

    Science.gov (United States)

    Vdovin, V. F.; Grachev, V. G.; Dryagin, S. Yu.; Eliseev, A. I.; Kamaletdinov, R. K.; Korotaev, D. V.; Lesnov, I. V.; Mansfeld, M. A.; Pevzner, E. L.; Perminov, V. G.; Pilipenko, A. M.; Sapozhnikov, B. D.; Saurin, V. P.

    2016-01-01

    We report a design solution for a highly reliable, low-noise and extremely efficient cryogenically cooled transmit/receive unit for a large antenna system meant for radio-astronomical observations and deep-space communications in the X band. We describe our design solution and the results of a series of laboratory and antenna tests carried out in order to investigate the properties of the cryogenically cooled low-noise amplifier developed. The transmit/receive unit designed for deep-space communications (Mars missions, radio observatories located at Lagrangian point L2, etc.) was used in practice for communication with live satellites including "Radioastron" observatory, which moves in a highly elliptical orbit.

  1. Observation of radiation environment in the International Space Station in 2012–March 2013 by Liulin-5 particle telescope

    Directory of Open Access Journals (Sweden)

    Semkova Jordanka

    2014-01-01

    Full Text Available Since June 2007 the Liulin-5 charged particle telescope, located in the spherical tissue-equivalent phantom of the MATROSHKA-R project onboard the International Space Station (ISS, has been making measurements of the local energetic particle radiation environment. From 27 December 2011 to 09 March 2013 measurements were conducted in and outside the phantom located in the MIM1 module of the ISS. In this paper Liulin-5 dose rates, due to galactic cosmic rays and South Atlantic Anomaly trapped protons, measured during that period are presented. Particularly, dose rates and particle fluxes for the radiation characteristics in the phantom during solar energetic particle (SEP events occurring in March and May 2012 are discussed. Liulin-5 SEP observations are compared with other ISS data, GOES proton fluxes as well as with solar energetic particle measurements obtained onboard the Mir space station during previous solar cycles.

  2. Observations of Earth space by self-powered stations in Antarctica.

    Science.gov (United States)

    Mende, S B; Rachelson, W; Sterling, R; Frey, H U; Harris, S E; McBride, S; Rosenberg, T J; Detrick, D; Doolittle, J L; Engebretson, M; Inan, U; Labelle, J W; Lanzerotti, L J; Weatherwax, A T

    2009-12-01

    Coupling of the solar wind to the Earth magnetosphere/ionosphere is primarily through the high latitude regions, and there are distinct advantages in making remote sensing observations of these regions with a network of ground-based observatories over other techniques. The Antarctic continent is ideally situated for such a network, especially for optical studies, because the larger offset between geographic and geomagnetic poles in the south enables optical observations at a larger range of magnetic latitudes during the winter darkness. The greatest challenge for such ground-based observations is the generation of power and heat for a sizable ground station that can accommodate an optical imaging instrument. Under the sponsorship of the National Science Foundation, we have developed suitable automatic observing platforms, the Automatic Geophysical Observatories (AGOs) for a network of six autonomous stations on the Antarctic plateau. Each station housed a suite of science instruments including a dual wavelength intensified all-sky camera that records the auroral activity, an imaging riometer, fluxgate and search-coil magnetometers, and ELF/VLF and LM/MF/HF receivers. Originally these stations were powered by propane fuelled thermoelectric generators with the fuel delivered to the site each Antarctic summer. A by-product of this power generation was a large amount of useful heat, which was applied to maintain the operating temperature of the electronics in the stations. Although a reasonable degree of reliability was achieved with these stations, the high cost of the fuel air lift and some remaining technical issues necessitated the development of a different type of power unit. In the second phase of the project we have developed a power generation system using renewable energy that can operate automatically in the Antarctic winter. The most reliable power system consists of a type of wind turbine using a simple permanent magnet rotor and a new type of power

  3. Observations of Earth space by self-powered stations in Antarctica

    Science.gov (United States)

    Mende, S. B.; Rachelson, W.; Sterling, R.; Frey, H. U.; Harris, S. E.; McBride, S.; Rosenberg, T. J.; Detrick, D.; Doolittle, J. L.; Engebretson, M.; Inan, U.; Labelle, J. W.; Lanzerotti, L. J.; Weatherwax, A. T.

    2009-12-01

    Coupling of the solar wind to the Earth magnetosphere/ionosphere is primarily through the high latitude regions, and there are distinct advantages in making remote sensing observations of these regions with a network of ground-based observatories over other techniques. The Antarctic continent is ideally situated for such a network, especially for optical studies, because the larger offset between geographic and geomagnetic poles in the south enables optical observations at a larger range of magnetic latitudes during the winter darkness. The greatest challenge for such ground-based observations is the generation of power and heat for a sizable ground station that can accommodate an optical imaging instrument. Under the sponsorship of the National Science Foundation, we have developed suitable automatic observing platforms, the Automatic Geophysical Observatories (AGOs) for a network of six autonomous stations on the Antarctic plateau. Each station housed a suite of science instruments including a dual wavelength intensified all-sky camera that records the auroral activity, an imaging riometer, fluxgate and search-coil magnetometers, and ELF/VLF and LM/MF/HF receivers. Originally these stations were powered by propane fuelled thermoelectric generators with the fuel delivered to the site each Antarctic summer. A by-product of this power generation was a large amount of useful heat, which was applied to maintain the operating temperature of the electronics in the stations. Although a reasonable degree of reliability was achieved with these stations, the high cost of the fuel air lift and some remaining technical issues necessitated the development of a different type of power unit. In the second phase of the project we have developed a power generation system using renewable energy that can operate automatically in the Antarctic winter. The most reliable power system consists of a type of wind turbine using a simple permanent magnet rotor and a new type of power

  4. Hubble space telescope and ground-based observations of the type Iax supernovae SN 2005hk and SN 2008A

    Energy Technology Data Exchange (ETDEWEB)

    McCully, Curtis; Jha, Saurabh W. [Department of Physics and Astronomy, Rutgers, the State University of New Jersey, 136 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Foley, Ryan J. [Astronomy Department, University of Illinois at Urbana-Champaign, 1002 West Green Street, Urbana, IL 61801 (United States); Chornock, Ryan [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Holtzman, Jon A. [Department of Astronomy, MSC 4500, New Mexico State University, P.O. Box 30001, Las Cruces, NM 88003 (United States); Balam, David D. [Dominion Astrophysical Observatory, Herzberg Institute of Astrophysics, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Branch, David [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, OK 73019 (United States); Filippenko, Alexei V.; Ganeshalingam, Mohan; Li, Weidong [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Frieman, Joshua [Kavli Institute for Cosmological Physics and Department of Astronomy and Astrophysics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Fynbo, Johan; Leloudas, Giorgos [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen Ø (Denmark); Galbany, Lluis [Institut de Física d' Altes Energies, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Barcelona) (Spain); Garnavich, Peter M. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Graham, Melissa L. [Las Cumbres Observatory Global Telescope Network, Goleta, CA 93117 (United States); Hsiao, Eric Y. [Carnegie Observatories, Las Campanas Observatory, Colina El Pino, Casilla 601 (Chile); Leonard, Douglas C., E-mail: cmccully@physics.rutgers.edu [Department of Astronomy, San Diego State University, San Diego, CA 92182 (United States); and others

    2014-05-10

    We present Hubble Space Telescope (HST) and ground-based optical and near-infrared observations of SN 2005hk and SN 2008A, typical members of the Type Iax class of supernovae (SNe). Here we focus on late-time observations, where these objects deviate most dramatically from all other SN types. Instead of the dominant nebular emission lines that are observed in other SNe at late phases, spectra of SNe 2005hk and 2008A show lines of Fe II, Ca II, and Fe I more than a year past maximum light, along with narrow [Fe II] and [Ca II] emission. We use spectral features to constrain the temperature and density of the ejecta, and find high densities at late times, with n{sub e} ≳ 10{sup 9} cm{sup –3}. Such high densities should yield enhanced cooling of the ejecta, making these objects good candidates to observe the expected 'infrared catastrophe', a generic feature of SN Ia models. However, our HST photometry of SN 2008A does not match the predictions of an infrared catastrophe. Moreover, our HST observations rule out a 'complete deflagration' that fully disrupts the white dwarf for these peculiar SNe, showing no evidence for unburned material at late times. Deflagration explosion models that leave behind a bound remnant can match some of the observed properties of SNe Iax, but no published model is consistent with all of our observations of SNe 2005hk and 2008A.

  5. Hubble Space Telescope and Ground-Based Observations of the Type Iax Supernovae SN 2005hk and SN 2008A

    Energy Technology Data Exchange (ETDEWEB)

    McCully, Curtis; Jha, Saurabh W.; Foley, Ryan J.; Chornock, Ryan; Holtzman, Jon A.; Balam, David D.; Branch, David; Filippenko, Alexei V.; Frieman, Joshua; Fynbo, Johan; Galbany, Lluis; Ganeshalingam, Mohan; Garnavich, Peter M.; Graham, Melissa L.; Hsiao, Eric Y.; Leloudas, Giorgos; Leonard, Douglas C.; Li, Weidong; Riess, Adam G.; Sako, Masao; Schneider, Donald P.; Silverman, Jeffrey M.; Sollerman, Jesper; Steele, Thea N.; Thomas, Rollin C.; Wheeler, J. Craig; Zheng, Chen

    2014-04-24

    We present Hubble Space Telescope (HST) and ground-based optical and near-infrared observations of SN 2005hk and SN 2008A, typical members of the Type Iax class of supernovae (SNe). Here we focus on late-time observations, where these objects deviate most dramatically from all other SN types. Instead of the dominant nebular emission lines that are observed in other SNe at late phases, spectra of SNe 2005hk and 2008A show lines of Fe II, Ca II, and Fe I more than a year past maximum light, along with narrow [Fe II] and [Ca II] emission. We use spectral features to constrain the temperature and density of the ejecta, and find high densities at late times, with ne109 cm–3. Such high densities should yield enhanced cooling of the ejecta, making these objects good candidates to observe the expected "infrared catastrophe," a generic feature of SN Ia models. However, our HST photometry of SN 2008A does not match the predictions of an infrared catastrophe. Moreover, our HST observations rule out a "complete deflagration" that fully disrupts the white dwarf for these peculiar SNe, showing no evidence for unburned material at late times. Deflagration explosion models that leave behind a bound remnant can match some of the observed properties of SNe Iax, but no published model is consistent with all of our observations of SNe 2005hk and 2008A.

  6. The James Webb Space Telescope's Plan for Operations and Instrument Capabilities for Observations in the Solar System

    Science.gov (United States)

    Milam, Stefanie N.; Stansberry, John A.; Sonneborn, George; Thomas, Cristina

    2016-01-01

    The James Webb Space Telescope (JWST) is optimized for observations in the near- and mid-infrared and will provide essential observations for targets that cannot be conducted from the ground or other missions during its lifetime. The state-of-the-art science instruments, along with the telescope's moving target tracking, will enable the infrared study, with unprecedented detail, for nearly every object (Mars and beyond) in the Solar System. The goals of this special issue are to stimulate discussion and encourage participation in JWST planning among members of the planetary science community. Key science goals for various targets, observing capabilities for JWST, and highlights for the complementary nature with other missions/observatories are described in this paper.

  7. Evaluation of observable phase space by fast ion loss detector by calculating particle orbits in consideration of plasma facing components and three dimensional magnetic field

    Science.gov (United States)

    Shinohara, Kouji; Kim, Junghee; Kim, Jun Young; Rhee, Tongnyeol

    2016-11-01

    The orbits of lost ions can be calculated from the information obtained by a fast ion loss detector (FILD). The orbits suggest a source of the lost fast ions in a phase space. However, it is not obvious whether an observable set of orbits, or phase space, of a FILD appropriately covers the region of interest to be investigated since the observable phase space can be affected by plasma facing components (PFCs) and a magnetic configuration. A tool has been developed to evaluate the observable phase space of FILD diagnostic by calculating particle orbits by taking the PFCs and 3D magnetic field into account.

  8. Personal Active Dosimeter for Space: the Light Observer for Radiation Environment (LORE) project

    Science.gov (United States)

    Narici, Livio

    Long permanence in space outside the protections of the Earth magnetic shield and atmosphere (during long journeys, and on the Moon or/and Mars) requires a careful monitoring of absorbed doses by each astronaut. This is of paramount importance for transient and cumulative effects mostly due to Solar Particle Events. Alarming features and the possibility of monitoring absorbed dose also discriminating the kind of incoming radiation will be needed. Stemming from our large experience in detector building, in modelling, in designing of the supporting electronic, from our payloads flown on satellites, MIR Station and ISS (Nina, Mita, SilEye, SilEye2, Alteino, Pamela, ALTEA) we are developping a personal active dosimeter with alarming and wireless features. The goal is a small object able to measure charged and neutral ionizing radiation (the possibility to insert a miniaturized gamma detector will be investigated) The device will feature portability (cigarette-box dimensions, rechargeable batteries), sensitivity to ions (H to above Fe), to hard X-rays, and possibly to gamma with the ability to detect and count neutrons. Flash memories should contain pre loaded tables and the real Time code to perform the real time operations and risk thresholds so to activate an alarm if/when needed. Whenever in range, the device will connect wirelessly to the main computer and send there the raw and pre-analyzed data for a complete monitoring and possible more sophisticated analyses. The two major novelties and challenges in this project are the miniaturization of the device, including the firmware, and the definition of the transfer function and of its uncertainties, linking measured data with real flux data. This will require the proper balancing among size, radiation discrimination ability and uncertainty minimization.

  9. Quantitative observation of cyanobacteria and diatoms from space using PhytoDOAS on SCIAMACHY data

    Directory of Open Access Journals (Sweden)

    A. Bracher

    2009-05-01

    Full Text Available In this study the technique of Differential Optical Absorption Spectroscopy (DOAS has been adapted for the retrieval of the absorption and biomass of two major phytoplankton groups (PhytoDOAS from data of the Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY satellite sensor. SCIAMACHY measures back scattered solar radiation in the UV-Vis-NIR spectral regions with a high spectral resolution (0.2 to 1.5 nm. In order to identify phytoplankton absorption characteristics in the SCIAMACHY data in the range of 430 to 500 nm, phytoplankton absorption spectra measured in-situ during two different RV "Polarstern" expeditions were used. The two spectra have been measured in different ocean regions where different phytoplankton groups (cyanobacteria and diatoms dominated the phytoplankton composition. Results clearly show distinct absorption characteristics of the two phytoplankton groups in the SCIAMACHY spectra. Using these results in addition to calculations of the light penetration depth derived from DOAS retrievals of the inelastic scattering (developed by Vountas et al., 2007, globally distributed pigment concentrations for these characteristic phytoplankton groups for two monthly periods (February–March 2004 and October–November 2005 were determined. This satellite information on cyanobacteria and diatoms distribution clearly matches the concentrations based on high pressure liquid chromatography (HPLC pigment analysis of collocated water samples and concentrations derived from a global model analysis with the NASA Ocean Biogeochemical Model (Gregg et al., 2003; Gregg and Casey 2007. The quantitative assessment of the distribution of key phytoplankton groups from space enables various biogeochemical regions to be distinguished and will be of great importance for the global modeling of marine ecosystems and biogeochemical cycles which enables the impact of climate change in the oceanic biosphere to be estimated.

  10. Quantitative observation of cyanobacteria and diatoms from space using PhytoDOAS on SCIAMACHY data

    Directory of Open Access Journals (Sweden)

    A. Bracher

    2008-11-01

    Full Text Available In this study the technique Differential Optical Absorption Spectroscopy (DOAS has been adapted for the retrieval of the absorption and biomass of two major phytoplankton groups (PhytoDOAS from data of the satellite sensor Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY. SCIAMACHY measures back scattered solar radiation in the UV-Vis-NIR spectral region with a high spectral resolution (0.2 to 1.5 nm. In order to identify phytoplankton absorption characteristics in SCIAMACHY data in the range of 430 to 500 nm, phytoplankton absorption spectra measured in-situ during two different RV "Polarstern" expeditions were used. The two spectra have been measured in different ocean regions where different phytoplankton groups (cyanobacteria and diatoms dominated the phytoplankton composition. Results show clearly different absorption characteristics of the phytoplankton groups in the SCIAMACHY spectra. Globally distributed pigment concentrations for these characteristic phytoplankton groups for two monthly periods (February–March 2004 and October–November 2005 were derived from these differential absorptions by including the information of the sensor's optical paths within the water column (i.e. light penetration depth according to Vountas et al. (2007 derived from DOAS fits of inelastic scattering. The satellite retrieved information on cyanobacteria and diatoms distribution matches well the concentrations measured at collocated water samples with HPLC technique and concentrations derived from the global model analysis with the NOBM model (Gregg et al., 2003; Gregg and Casey, 2007. Identifying quantitative distribution of key phytoplankton groups from space allow to distinguish various biogeochemical provinces and will be of great importance for the global modelling of marine ecosystem and biogeochemical cycles addressing climate changes in the oceanic biosphere.

  11. Courthouse Design Principles to Dignify Spaces for Indigenous Users: preliminary observations

    Directory of Open Access Journals (Sweden)

    Thalia Anthony

    2016-11-01

    Full Text Available Historically, Australian court architecture layout, design and details are intimately tied to the physical aspects of British imperial institutions.  Displaying the visual features of the Empire’s institutions has the effect of alienating Indigenous people within courts. This is compounded by design that is oblivious to the needs of Indigenous users and consequently places these users in situations that threaten their privacy, safety and wellbeing. This article contends that architectural design that seeks to accommodate Indigenous cultural and socio- spatial needs brings into sharp relief the barriers and harms otherwise confronting Indigenous people in courts. This article discusses three court complexes designed in collaboration with Indigenous communities to accommodate Indigenous connections to the environment surrounding the courthouse and to enhance access to justice. Indigenous collaborations in the design of the Indigenous-inclusive court complexes at Port Augusta (South Australia, Kalgoorlie and Kununurra (Western Australia produced spatially distinct courthouses that eschew some historical court design principles and attempt to introduce features relevant to local Indigenous nations. This illustration essay discusses the emergence of Indigenous design principles that may inform courthouse redesign, the application of some of these principles in new courthouse designs and the need for local Indigenous oversight in the design processes. It provides a framework for further research into how Indigenous architectural collaborations in courthouse designs may promote safer and fairer environments for Indigenous court users. It also raises some potential disjuncture between court design and use of court space that may undermine the vision embedded in cultural design principles.

  12. In situ observations from STEREO/PLASTIC: a test for L5 space weather monitors

    Directory of Open Access Journals (Sweden)

    K. D. C. Simunac

    2009-10-01

    Full Text Available Stream interaction regions (SIRs that corotate with the Sun (corotating interaction regions, or CIRs are known to cause recurrent geomagnetic storms. The Earth's L5 Lagrange point, separated from the Earth by 60 degrees in heliographic longitude, is a logical location for a solar wind monitor – nearly all SIRs/CIRs will be observed at L5 several days prior to their arrival at Earth. Because the Sun's heliographic equator is tilted about 7 degrees with respect to the ecliptic plane, the separation in heliographic latitude between L5 and Earth can be more than 5 degrees. In July 2008, during the period of minimal solar activity at the end of solar cycle 23, the two STEREO observatories were separated by about 60 degrees in longitude and more than 4 degrees in heliographic latitude. This time period affords a timely test for the practical application of a solar wind monitor at L5. We compare in situ observations from PLASTIC/AHEAD and PLASTIC/BEHIND, and report on how well the BEHIND data can be used as a forecasting tool for in situ conditions at the AHEAD spacecraft with the assumptions of ideal corotation and minimal source evolution. Preliminary results show the bulk proton parameters (density and bulk speed are not in quantitative agreement from one observatory to the next, but the qualitative profiles are similar.

  13. Time biases in laser ranging observations: A concerning issue of Space Geodesy

    Science.gov (United States)

    Exertier, Pierre; Belli, A.; Lemoine, J. M.

    2017-09-01

    Time transfer by Laser Ranging (LR) recently demonstrated a remarkable stability (a few ps over ∼1000 s) and accuracy (service. The approach we investigate is to compute time synchronization between clocks used at LR stations using accurate data of the Time Transfer by Laser Link (T2L2) experiment onboard the satellite Jason-2 (Samain et al., 2014). Systematic time biases are estimated against the UTC time scale for a set of 22 observing stations in 2013, in the range of zero to a few μ s. Our results suggest that the ILRS network suffers from accuracy issues, due to time biases in the laser ranging observations. We discuss how these systematic effects impact the precise orbit determination of LAGEOS geodetic satellites over a 1-year analysis, and additionally give a measure of the local effect into station coordinates, regarding in particular the effect in the east-west component that is of 2-6 mm for a typical systematic time bias of one μ s.

  14. Wide-Field Hubble Space Telescope Observations of the Globular Cluster System in NGC 1399*

    Science.gov (United States)

    Puzia, Thomas H.; Paolillo, Maurizio; Goudfrooij, Paul; Maccarone, Thomas J.; Fabbiano, Giuseppina; Angelini, Lorella

    2014-01-01

    We present a comprehensive high spatial resolution imaging study of globular clusters (GCs) in NGC 1399, thecentral giant elliptical cD galaxy in the Fornax galaxy cluster, conducted with the Advanced Camera for Surveys(ACS) aboard theHubble Space Telescope(HST).Using a novel technique to construct drizzled point-spreadfunction libraries for HSTACS data, we accurately determine the fidelity of GC structural parameter measurementsfrom detailed artificial star cluster experiments and show the superior robustness of the GC half-light radius,rh,compared with other GC structural parameters, such as King core and tidal radius. The measurement ofrhfor themajor fraction of the NGC 1399 GC system reveals a trend of increasingrhversus galactocentric distance,Rgal,out to about 10 kpc and a flat relation beyond. This trend is very similar for blue and red GCs, which are found tohave a mean size ratio ofrh,redrh,blue0.820.11 at all galactocentric radii from the core regions of the galaxyout to40 kpc. This suggests that the size difference between blue and red GCs is due to internal mechanismsrelated to the evolution of their constituent stellar populations. Modeling the mass density profile of NGC 1399shows that additional external dynamical mechanisms are required to limit the GC size in the galaxy halo regionstorh2 pc. We suggest that this may be realized by an exotic GC orbit distribution function, an extended darkmatter halo, andor tidal stress induced by the increased stochasticity in the dwarf halo substructure at largergalactocentric distances. We compare our results with the GCrhdistribution functions in various galaxies and findthat the fraction of extended GCs withrh5 pc is systematically larger in late-type galaxies compared with GCsystems in early-type galaxies. This is likely due to the dynamically more violent evolution of early-type galaxies.We match our GCrhmeasurements with radial velocity data from the literature and split the resulting sample at

  15. Space-borne and ground-based observation of Aerosols in China and an overview of the EAST-AIRE

    Science.gov (United States)

    Li, Z.; Holben, B.; Xia, X.; Xin, J.; Dickerson, R.

    2006-05-01

    China is a region of heavy aerosol loading of distinct and complex properties. To date, few in-situ measurements were made of the physical properties and chemical composition of the aerosols near the source regions. A lack of aerosol properties, together with relative bright surfaces, makes the retrieval of aerosols from space challenging and uncertain. In order to gain a basic knowledge of the characteristics of aerosols and to improve satellite retrievals, a team of scientists from U.S. and China conduct joint field measurements in the form of routine observations at fixed sites, and intensive observation campaigns. Major findings will be presented concerning both the aerosol properties and their spatial and temporal variations using ground-based and space-borne remote sensing techniques, as well as in-situ observation techniques. The results reveal that the mean aerosol loading is on average larger by several factors than the global mean values. All existing satellite aerosol retrieved products contain exceptionally large errors. Yet, the aerosol absorption is so strong that lead to extremely large forcing at the surface but very small at the TOA. A large fraction of major aerosol episodes are caused by anthropogenic emissions that are built up by stable atmospheric conditions.

  16. Real-space observation of magnetic excitations and avalanche behavior in artificial quasicrystal lattices

    Science.gov (United States)

    Brajuskovic, V.; Barrows, F.; Phatak, C.; Petford-Long, A. K.

    2016-10-01

    Artificial spin ice lattices have emerged as model systems for studying magnetic frustration in recent years. Most work to date has looked at periodic artificial spin ice lattices. In this paper, we observe frustration effects in quasicrystal artificial spin ice lattices that lack translational symmetry and contain vertices with different numbers of interacting elements. We find that as the lattice state changes following demagnetizing and annealing, specific vertex motifs retain low-energy configurations, which excites other motifs into higher energy configurations. Additionally, we find that unlike the magnetization reversal process for periodic artificial spin ice lattices, which occurs through 1D avalanches, quasicrystal lattices undergo reversal through a dendritic 2D avalanche mechanism.

  17. Crowding by a repeating pattern.

    Science.gov (United States)

    Rosen, Sarah; Pelli, Denis G

    2015-01-01

    Theinability to recognize a peripheral target among flankers is called crowding. For a foveal target, crowding can be distinguished from overlap masking by its sparing of detection, linear scaling with eccentricity, and invariance with target size.Crowding depends on the proximity and similarity of the flankers to the target. Flankers that are far from or dissimilar to the target do not crowd it. On a gray page, text whose neighboring letters have different colors, alternately black and white, has enough dissimilarity that it might escape crowding. Since reading speed is normally limited by crowding, escape from crowding should allow faster reading. Yet reading speed is unchanged (Chung & Mansfield, 2009). Why? A recent vernier study found that using alternating-color flankers produces strong crowding (Manassi, Sayim, & Herzog, 2012). Might that effect occur with letters and reading? Critical spacing is the minimum center-to-center target-flanker spacing needed to correctly identify the target. We measure it for a target letter surrounded by several equidistant flanker letters of the same polarity, opposite polarity, or mixed polarity: alternately white and black. We find strong crowding in the alternating condition, even though each flanker letter is beyond its own critical spacing (as measured in a separate condition). Thus a periodic repeating pattern can produce crowding even when the individual elements do not. Further, in all conditions we find that, once a periodic pattern repeats (two cycles), further repetition does not affect critical spacing of the innermost flanker.

  18. Anthropogenic emissions and space-borne observations of carbon monoxide over South Asia

    Science.gov (United States)

    Ul-Haq, Zia; Tariq, Salman; Ali, Muhammad

    2016-11-01

    The focus of this study is to understand anthropogenic emissions, spatiotemporal variability and trends of carbon monoxide (CO) over South Asia by using datasets from MACCity (Monitoring Atmospheric Composition and Climate, MACC and megaCITY - Zoom for the Environment, CityZEN), REAS (Regional Emission inventory in Asia), AIRS (Atmospheric Infrared Sounder) and SCIAMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CartograpHY). MACCity anthropogenic emissions show an overall increase of 16.5% during 2000-2010. Elevated levels of MACCity CO are found in Indo-Gangetic Basin (IGB), eastern mining region of India, Bangladesh and large urban areas. Some of the major contributors of these emissions have been identified as agricultural waste burning, land transport, industrial production, and energy generation and distribution. An area averaged mean value of AIRS CO at 600 hPa is found to be 114 ± 2 ppbv (slope -0.48 ± 0.2 ppbv yr-1, y-intercept 117 ± 1 ppbv and r = 0.68) with a minor declining trend at -0.41 ± 0.18% yr-1 over the region during 2003-2015. A strong seasonality in AIRS CO concentration is observed with spring season peak in March 129 ± 1.9 ppbv, whereas low values have been observed in summer monsoon with sturdy dip in July 99.6 ± 1.94 ppbv. AIRS CO and SCIAMACHY CO Total Column (CO TC) over the study region show spatial patterns similar to MACCity and REAS emissions. An analysis of SCIAMACHY CO TC tendencies has been performed which indicates minor rising trends over some parts of the region. Background CO, Recent Emissions (RE), and spatial anomalies in RE over high anthropogenic activity zones of Indus Basin, Ganges Basin and Eastern Region were analyzed using AIRS and SCIAMACHY CO data.

  19. Space-charge-limited conduction in Se90Sb4Ag6 glassy alloy: observation of Meyer–Neldel rule

    Indian Academy of Sciences (India)

    Anjani Kumar; A Kumar

    2015-02-01

    The present paper reports the measurements of space-charge-limited conduction (SCLC) in glassy Se90Sb4Ag6 alloy. For this purpose, – characteristics have been taken at certain fixed temperatures. The results indicate that super-ohmic behaviour is observed at high electric fields. The results fit well with the theory of SCLC for the uniform distribution of traps. From the temperature dependence of conductivity, activation energy is obtained at different electric fields, which is found to be field dependent. Pre-exponential factor is found to depend on the activation energy and obeys Meyer–Neldel rule.

  20. Sensorless State-Space Control of Elastic Two-Inertia Drive System Using a Minimum State Order Observer

    Directory of Open Access Journals (Sweden)

    V. Comnac

    2009-12-01

    Full Text Available The paper presents sensorless state-space control of two-inertia drive system with resilient coupling. The control structure contains an I+PI controller for load speed regulation and a state feedback controller for effective vibration suppression of the elastic coupling. Mechanical state variable of two-inertia drive are obtained by using a linear minimum-order (Gopinath state observer. The design of the combined (I+PI and state feedback controller is achieved with the extended version of the modulus criterion [5]. The dynamic behavior of presented control structure has been examined, for different conditions, using MATLAB/SIMULINK simulation.

  1. Ozone Enhancement in the Lower Troposphere over Central and Eastern China as Observed from the space

    Science.gov (United States)

    Maki, T.; Hayashida, S.; Ono, A.; Kayaba, S.; Kajino, M.; Deushi, M.; Sekiyama, T. T.; Yamaji, K.; Liu, X.

    2015-12-01

    The recent roducts of the Ozone Monitoring Instrument (OMI) retrieved by Liu et al. (2010) revealed spatial and temporal variations in ozone distributions in multiple tropospheric layers. We compared the OMI-derived ozone over Beijing with the airborne measurements conducted by the Measurement of Ozone and Water Vapor by Airbus In-Service Aircraft (MOZAIC) program. The reliability of the OMI ozone retrievals was verified at the lower troposphere under enhanced ozone conditions (Hayashida et al. 2015). Ozone enhancement was clearly observed over Central and Eastern China (CEC), with Shandong Province as its center and most notably in June in any given year. The seasonality of the ozone enhancement was similar throughout the nine-year OMI measurement period of 2005 to 2013. As introduced by Hayashida et al. (2015), we have defined ΔO3 as the difference between the retrieved ozone and a priori value. To identify the area of significant ozone enhancement in further detail, the areas whose ΔO3 show similar seasonal variation were grouped into a cluster using the statistical tool R. As a result, the area covering the provinces of Shandong, Hebei, and Shanxi presents a clear seasonal variation, with the maximum in June. The time series of ΔO3 at around 115-125°E along 36°N indicate clear seasonal variation with significant enhancement in June or July every year. At the western locations (<110°E), there is only a slight ozone enhancement in summer. In the east of the CEC, the amplitude of ozone enhancement in summer diminishes toward the east, as observed at 130°E, suggesting an outflow of ozone plumes from China. The lower tropospheric ozone distribution maps retrieved using OMI products are generally consistent with the results from the model simulations by MRI-CCM2 of the Meteorological Research Institute Japan as far as emissions due to industrial activities and automobile exhaust are concerned, although there are still a few differences in the ozone mixing

  2. Occultation observations of atmosphere and climate change from space: a backbone for the GCOS

    Science.gov (United States)

    Kirchengast, G.

    2003-04-01

    , involving the heavily calibration-dependent Microwave Sounding Unit (MSU) data, could have been presumably saved had suitable occultation data been available. This talk will highlight, along the lines outlined above, the general principles, properties, capabilities, and exploitation possibilities of occultation methods with a focus on how they provide key contributions to a better understanding of the Earth's climate system and to better prediction of its future evolution. A properly designed occultation observing system has the capacity to become the leading backbone of the Global Climate Observing System (GCOS) for monitoring climate change and variability in fundamental atmospheric variables such as temperature, humidity, ozone, and geopotential height from global scales to meso-scales (order 100 km) and from the planetary boundary layer to the mesopause.

  3. Testing the asymptotic relation for period spacings from mixed modes of red giants observed with the Kepler mission

    CERN Document Server

    Buysschaert, B; Corsaro, E; Christensen-Dalsgaard, J; Aerts, C; Arentoft, T; Kjeldsen, H; García, R A; Aguirre, V Silva; Degroote, P

    2016-01-01

    Dipole mixed pulsation modes of consecutive radial order have been detected for thousands of low-mass red-giant stars with the NASA space telescope Kepler. Such modes have the potential to reveal information on the physics of the deep stellar interior. Different methods have been proposed to derive an observed value for the gravity-mode period spacing, the most prominent one relying on a relation derived from asymptotic pulsation theory applied to the gravity-mode character of the mixed modes. Our aim is to compare results based on this asymptotic relation with those derived from an empirical approach for three pulsating red-giant stars. We developed a data-driven method to perform frequency extraction and mode identification. Next, we used the identified dipole mixed modes to determine the gravity-mode period spacing by means of an empirical method and by means of the asymptotic relation. In our methodology, we consider the phase offset, $\\epsilon_{\\mathrm{g}}$, of the asymptotic relation as a free parameter...

  4. Bi-layer Kinetic Inductance Detectors for space observations between 80-120 GHz

    CERN Document Server

    Catalano, A; Sueur, H le; Benoit, A; Bourrion, O; Calvo, M; Dumoulin, L; Levy-Bertrand, F; Macìas-Pérez, J; Marnieros, S; Ponthieu, N; Monfardini, A

    2015-01-01

    We have developed Lumped Element Kinetic Inductance Detectors (LEKID) sensitive in the frequency band from 80 to 120~GHz. In this work, we take advantage of the so-called proximity effect to reduce the superconducting gap of Aluminium, otherwise strongly suppressing the LEKID response for frequencies smaller than 100~GHz. We have designed, produced and optically tested various fully multiplexed arrays based on multi-layers combinations of Aluminium (Al) and Titanium (Ti). Their sensitivities have been measured using a dedicated closed-circle 100 mK dilution cryostat and a sky simulator allowing to reproduce realistic observation conditions. The spectral response has been characterised with a Martin-Puplett interferometer up to THz frequencies, and with a resolution of 3~GHz. We demonstrate that Ti-Al LEKID can reach an optical sensitivity of about $1.4$ $10^{-17}$~$W/Hz^{0.5}$ (best pixel), or $2.2$ $10^{-17}$~$W/Hz^{0.5}$ when averaged over the whole array. The optical background was set to roughly 0.4~pW pe...

  5. Observations from Space: Marine Ecosystem and Environment Response to Typhoon/ Hurricanes

    Science.gov (United States)

    Tang, Danling; Yi, Sui

    Marine ecosystem is sensitive to environmental factors, including typhoon. Typhoon's activities have been strengthening in both intensity and spatial coverage in the past several decades, along with global changes; however, our knowledge about the impact of typhoons upon the marine ecosystem is very scarce. To understand how could typhoon/hurricane impact on marine ecosystem, we have conducted a series studies in the South China Sea, by using Satellite remote sensing and in situ observation data to investigate phytoplankton concentration, sea surface temperature (SST) and related factors before, during, and after typhoon. Results show that typhoon can induce large area of phytoplankton blooms with increases of Chlorophyll a (Chl a) concentrations and decrease of sea surface temperature (SST) about 4 oC. Analysis showed that typhoon can support nutrients to surface phytoplankton by upwelling and vertical mixing, and typhoon rain can also nourish marine phytoplankton. More observations confirmed that typhoon can induce cold eddy, and cold eddy can support eddy-shape phyto-plankton bloom by upwelling. Typhoon can also induce transport of nutrient-rich water from depth and from the coast to offshore regions, nourishing phytoplankton biomass. Comparative study show that slow-moving typhoon induced phytoplankton blooms of higher Chlorophyll-a (Chl-a), the strong typhoon induced phytoplankton blooms of a large area. Therefore, typhoons may have important contribution to the marine primary production. Those studies may help better understand the mechanism of typhoon impacts on marine ecosys-tem, and the role of typhoon in the global environmental changes. The series research were sup-ported by: NSFC (40976091, 40811140533) and GD NSF (8351030101000002); (2) CAS(kzcx2-yw-226 and LYQ200701); (3) The CAS/SAFEA International Partnership Program for Creative Research Teams (KZCX2-YW-T001). References: Tang, DanLing, H Kawamura, P Shi, W Takahashi, T Shimada, F. Sakaida, O

  6. Inferring reservoir operating patterns across the Mekong Basin using only space observations

    Science.gov (United States)

    Bonnema, Matthew; Hossain, Faisal

    2017-05-01

    This study explores the operating pattern of artificial reservoirs by examining their impact on streamflow through two parameters, residence time and flow alteration, using a purely satellite-based technique for the Mekong Basin. Overall residence times of individual reservoirs ranged from 0.09 to 4.04 years, while streamflow was altered between 11 and 130% of its natural variability. The current set of reservoirs appears to have increased the residence time of the entire Mekong basin by about 1 month. However, if subbasin variability is considered, the satellite-based method depicts a different picture. Residence time increases to 4 months when only regulated flows are considered. If low residence time reservoirs on major rivers are excluded and reservoirs on higher stream-order rivers considered, residence time increases to 1.3 years. Predictable strong seasonal patterns emerged in residence time, where reservoirs experience higher residence time in the dry season and lower residence time in the wet season and residence time varies inversely with precipitation. High variability in reservoir effects on streamflow between reservoirs could not be explained by any reservoir properties (e.g., size, use, location, etc.), highlighting the variability in the human decisions operating these reservoirs. The take-home message of this study is that satellite observations, in combination with physical models forced with satellite data, can elucidate the spatiotemporal variability of reservoir behavior in ungauged basins of the developing world. We demonstrate in this study that the requirement for ground data to monitor current or historical behavior of dams is not necessary.

  7. From Ground Truth to Space: Surface, Subsurface and Remote Observations Associated with Nuclear Test Detection

    Science.gov (United States)

    Sussman, A. J.; Anderson, D.; Burt, C.; Craven, J.; Kimblin, C.; McKenna, I.; Schultz-Fellenz, E. S.; Miller, E.; Yocky, D. A.; Haas, D.

    2016-12-01

    Underground nuclear explosions (UNEs) result in numerous signatures that manifest on a wide range of temporal and spatial scales. Currently, prompt signals, such as the detection of seismic waves provide only generalized locations and the timing and amplitude of non-prompt signals are difficult to predict. As such, research into improving the detection, location, and identification of suspect events has been conducted, resulting in advancement of nuclear test detection science. In this presentation, we demonstrate the scalar variably of surface and subsurface observables, briefly discuss current capabilities to locate, detect and characterize potential nuclear explosion locations, and explain how emergent technologies and amalgamation of disparate data sets will facilitate improved monitoring and verification. At the smaller scales, material and fracture characterization efforts on rock collected from legacy UNE sites and from underground experiments using chemical explosions can be incorporated into predictive modeling efforts. Spatial analyses of digital elevation models and orthoimagery of both modern conventional and legacy nuclear sites show subtle surface topographic changes and damage at nearby outcrops. Additionally, at sites where such technology cannot penetrate vegetative cover, it is possible to use the vegetation itself as both a companion signature reflecting geologic conditions and showing subsurface impacts to water, nutrients, and chemicals. Aerial systems based on RGB imagery, light detection and ranging, and hyperspectral imaging can allow for combined remote sensing modalities to perform pattern recognition and classification tasks. Finally, more remote systems such as satellite based synthetic aperture radar and satellite imagery are other techniques in development for UNE site detection, location and characterization.

  8. Design, analysis, and testing of kinematic mount for astronomical observation instrument used in space camera

    Science.gov (United States)

    An, Mingxin; Zhang, Lihao; Xu, Shuyan; Dong, Jihong

    2016-11-01

    A statically determinate kinematic mount structure is designed for an astronomical observation instrument. The basic principle of the proposed kinematic mount is introduced in detail, including the design principle, its structure, and its degrees of freedom. The compliance equations for the single-axis right circle flexure hinge are deduced, and mathematical models of the compliances of the bipod in the X-axis and Z-axis directions are established. Based on the index requirements, the range of one design parameter (the hinge groove depth, R) for the kinematic mount is determined. Parametric design is performed, with the entire structure being the design object and the first three eigenfrequencies as the design objective; the final design parameter for the kinematic mount is 1.9 mm. The first three eigenfrequencies of the final structure are 36.49 Hz, 38.65 Hz, and 72.41 Hz, which meet the frequency requirements. The Z-direction deformation and the bipod compliances in the X-axis and Z-axis directions are analyzed through simulations and experiments. The results show that (1) the Z-direction deformation of the bipod meets the displacement requirement; (2) the deviations between the finite element results and the compliance equation Cx results, and between the finite element results and the compliance equation Cz results are 8.8% and 3.92%, respectively; (3) the deviation between the experimental results and the compliance equation Cz results is 10.3%. It is concluded that the bipod compliance equations in the X-axis and Z-axis directions are valid, and that the kinematic mount thus meets the design requirements.

  9. Space geodetic observation of the deformation cycle across the Ballenas Transform, Gulf of California

    Science.gov (United States)

    Plattner, Christina; Malservisi, Rocco; Amelung, Falk; Dixon, Timothy H.; Hackl, Matthias; Verdecchia, Alessandro; Lonsdale, Peter; Suarez-Vidal, Francisco; Gonzalez-Garcia, Javier

    2015-08-01

    The Gulf of California, Mexico, accommodates ~90% of North America-Pacific plate relative motion. While most of this motion occurs on marine transform faults and spreading centers, several fault segments in the central Gulf come close to peninsular Baja California. Here we present Global Positioning System and interferometric synthetic aperture radar data near the Ballenas transform fault, separating the peninsula from Angel de la Guarda Island. We observe interseismic motion between June 2004 and May 2009 and displacements associated with the 3 August 2009 Mw 6.9 earthquake. From the interseismic data we estimate a locking depth of 9-12.5 km and a slip rate of 44.9-48.1 mm/yr, indicating that faults east of Angel de la Guarda deform at negligible rates and that the Ballenas Transform accommodates virtually all of the relative motion between the North American plate and the Baja California microplate. Our preferred model for coseismic slip on a finite rectangular fault plane suggests 1.3 m of strike-slip displacement along a vertical rupture plane that is 60 km long and extends from the surface to a depth of 13 km in the eastern Ballenas Channel, striking parallel to Baja California-North America relative plate motion. These estimates agree with the seismic moment tensor and the location of the major foreshock and aftershocks and are compatible with the fault location identified from high-resolution bathymetric mapping. The geodetic moment is 33% higher than the seismic moment in part because some afterslip and viscous flow in the first month after the earthquake are included in the geodetic estimate. Coulomb stress changes for adjacent faults in the Gulf are consistent with the location of smaller aftershocks following the 2009 main shock and suggest potential triggering of the 12 April 2012 Mw 6.9 Guaymas earthquake.

  10. Observations of the Hubble Deep Field with the Infrared Space Observatory; 1, Data reduction, maps and sky coverage

    CERN Document Server

    Serjeant, S

    1997-01-01

    We present deep imaging at 6.7 micron and 15 micron from the CAM instrument on the Infrared Space Observatory (ISO), centred on the Hubble Deep Field (HDF). These are the deepest integrations published to date at these wavelengths in any region of sky. We discuss the observation strategy and the data reduction. The observed source density appears to approach the CAM confusion limit at 15 micron, and fluctuations in the 6.7 micron sky background may be identifiable with similar spatial fluctuations in the HDF galaxy counts. ISO appears to be detecting comparable field galaxy populations to the HDF, and our data yields strong evidence that future IR missions (such as SIRTF, FIRST and WIRE) as well as SCUBA and millimetre arrays will easily detect field galaxies out to comparably high redshifts.

  11. Quantum repeated games revisited

    CERN Document Server

    Frackiewicz, Piotr

    2011-01-01

    We present a scheme for playing quantum repeated 2x2 games based on the Marinatto and Weber's approach to quantum games. As a potential application, we study twice repeated Prisoner's Dilemma game. We show that results not available in classical game can be obtained when the game is played in the quantum way. Before we present our idea, we comment on the previous scheme of playing quantum repeated games.

  12. Space in environmental diplomacy: Exploring the role of earth observing satellites for monitoring international environmental agreements

    Science.gov (United States)

    Johnston, Shaida Sahami

    This research determines under what conditions, and for what types of environmental treaties, Earth observation (EO) is useful for monitoring international environmental agreements. The research extracts specific monitoring requirements from nine multilateral environmental agreements (MEAs) and explores how satellite EO data can be used to support them. The technical characteristics of the sensor systems and science data products associated with current and planned EO satellites were analyzed and mapped to the MEA requirements, providing a significant step toward linking the EO community with the international treaty community implementing these environmental agreements. The research results include a listing and analysis of the positive and negative factors that influence whether EO data are useful for monitoring and verifying MEAs, analysis of existing international EO institutions, and a set of key findings describing the conditions under which EO data are most useful to the treaties. The use of EO data in various treaty phases is also analyzed, drawing the conclusion that EO data are most useful for monitoring and treaty refinement and not very useful for compliance verification or enforcement. MEAs manage compliance using governance structures that offer expertise and resources to assist states that are reported to be in non-compliance, rather than enforce compliance with sanctions or other punishments. In addition, the temporal and spatial resolution of the current and planned fleet of satellites does not provide the required detail needed for MEA verification. Identifying specific treaty implementation deficiencies requires additional information that cannot be gathered from EO data; on-site economic, social, and environmental conditions are critical elements in assessing compliance verification. But for environmental monitoring and assessments, MEA effectiveness reviews, and national reporting required for each MEA, EO data are very useful. They provide

  13. From Geodesy to Tectonics: Observing Earthquake Processes from Space (Augustus Love Medal Lecture)

    Science.gov (United States)

    Parsons, Barry

    2017-04-01

    A suite of powerful satellite-based techniques has been developed over the past two decades allowing us to measure and interpret variations in the deformation around active continental faults occurring in earthquakes, before the earthquakes as strain accumulates, and immediately following them. The techniques include radar interferometry and the measurement of vertical and horizontal surface displacements using very high-resolution (VHR) satellite imagery. They provide near-field measurements of earthquake deformation facilitating the association with the corresponding active faults and their topographic expression. The techniques also enable pre- and post-seismic deformation to be determined and hence allow the response of the fault and surrounding medium to changes in stress to be investigated. The talk illustrates both the techniques and the applications with examples from recent earthquakes. These include the 2013 Balochistan earthquake, a predominantly strike-slip event, that occurred on the arcuate Hoshab fault in the eastern Makran linking an area of mainly left-lateral shear in the east to one of shortening in the west. The difficulty of reconciling predominantly strike-slip motion with this shortening has led to a wide range of unconventional kinematic and dynamic models. Using pre-and post-seismic VHR satellite imagery, we are able to determine a 3-dimensional deformation field for the earthquake; Sentinel-1 interferometry shows an increase in the rate of creep on a creeping section bounding the northern end of the rupture in response to the earthquake. In addition, we will look at the 1978 Tabas earthquake for which no measurements of deformation were possible at the time. By combining pre-seismic 'spy' satellite images with modern imagery, and pre-seismic aerial stereo images with post-seismic satellite stereo images, we can determine vertical and horizontal displacements from the earthquake and subsequent post-seismic deformation. These observations

  14. Effectiveness of media awareness campaigns on the proportion of vehicles that give space to ambulances on roads: An observational study.

    Science.gov (United States)

    Shaikh, Shiraz; Baig, Lubna A; Polkowski, Maciej

    2017-01-01

    The findings of the Health Care in Danger project in Karachi suggests that there is presence of behavioral negligence among vehicle operators on roads in regards to giving way to ambulances. A mass media campaign was conducted to raise people's awareness on the importance of giving way to ambulances. The main objective of this study was to determine the effectiveness of the campaign on increasing the proportion of vehicles that give way to ambulances. This was a quasi-experimental study that was based on before and after design. Three observation surveys were carried out in different areas of the city in Karachi, Pakistan before, during and after the campaign by trained observers who recorded their findings on a checklist. Each observation was carried out at three different times of the day for at least two days on each road. The relationship of the media campaign with regards to a vehicle giving space to an ambulance was calculated by means of odds ratios and 95% confidence intervals using multivariate logistic regression. Overall, 245 observations were included in the analysis. Traffic congestion and negligence/resistance, by vehicles operators who were in front of the ambulance, were the two main reasons why ambulances were not given way. Other reasons include: sudden stops by minibuses and in the process causing obstruction, ambulances not rushing through to alert vehicle operators to give way and traffic interruption by VIP movement. After adjustment for site, time of day, type of ambulance and number of cars in front of the ambulance, vehicles during (OR=2.13, 95% CI=1.22-3.71, p=0.007) and after the campaign (OR=1.73, 95% CI=1.02-2.95, p=0.042) were significantly more likely give space to ambulances. Mass media campaigns can play a significant role in changing the negligent behavior of people, especially when the campaign conveys a humanitarian message such as: giving way to ambulances can save lives.

  15. Towards sub-nanometer real-space observation of spin and orbital magnetism at the Fe/MgO interface.

    Science.gov (United States)

    Thersleff, Thomas; Muto, Shunsuke; Werwiński, Mirosław; Spiegelberg, Jakob; Kvashnin, Yaroslav; Hjӧrvarsson, Björgvin; Eriksson, Olle; Rusz, Ján; Leifer, Klaus

    2017-03-24

    While the performance of magnetic tunnel junctions based on metal/oxide interfaces is determined by hybridization, charge transfer, and magnetic properties at the interface, there are currently only limited experimental techniques with sufficient spatial resolution to directly observe these effects simultaneously in real-space. In this letter, we demonstrate an experimental method based on Electron Magnetic Circular Dichroism (EMCD) that will allow researchers to simultaneously map magnetic transitions and valency in real-space over interfacial cross-sections with sub-nanometer spatial resolution. We apply this method to an Fe/MgO bilayer system, observing a significant enhancement in the orbital to spin moment ratio that is strongly localized to the interfacial region. Through the use of first-principles calculations, multivariate statistical analysis, and Electron Energy-Loss Spectroscopy (EELS), we explore the extent to which this enhancement can be attributed to emergent magnetism due to structural confinement at the interface. We conclude that this method has the potential to directly visualize spin and orbital moments at buried interfaces in magnetic systems with unprecedented spatial resolution.

  16. Skylab experiments. Volume 5: Astronomy and space physics. [Skylab observations of galactic radiation, solar energy, and interplanetary composition for high school level education

    Science.gov (United States)

    1973-01-01

    The astronomy and space physics investigations conducted in the Skylab program include over 20 experiments in four categories to explore space phenomena that cannot be observed from earth. The categories of space research are as follows: (1) phenomena within the solar system, such as the effect of solar energy on Earth's atmosphere, the composition of interplanetary space, the possibility of an inner planet, and the X-ray radiation from Jupiter, (2) analysis of energetic particles such as cosmic rays and neutrons in the near-earth space, (3) stellar and galactic astronomy, and (4) self-induced environment surrounding the Skylab spacecraft.

  17. Reward modulation of contextual cueing: Repeated context overshadows repeated target location.

    Science.gov (United States)

    Sharifian, Fariba; Contier, Oliver; Preuschhof, Claudia; Pollmann, Stefan

    2017-08-07

    Contextual cueing can be enhanced by reward. However, there is a debate if reward is associated with the repeated target-distractor configurations or with the repeated target locations that occur in both repeated and new displays. Based on neuroimaging evidence, we hypothesized that reward becomes associated with the target location only in new displays, but not in repeated displays, where the repeated target location is overshadowed by the more salient repeated target-distractor configuration. To test this hypothesis, we varied the reward value associated with the same target location in repeated and new displays. The results confirmed the overshadowing hypothesis in that search facilitation in repeated target-distractor configurations was modulated by the variable value associated with the target location. This effect was observed mainly in early learning.

  18. Hubble Space Telescope and Ground-Based Observations of the Type Iax Supernovae SN 2005hk and SN 2008A

    CERN Document Server

    McCully, Curtis; Foley, Ryan J; Chornock, Ryan; Holtzman, Jon A; Balam, David D; Branch, David; Filippenko, Alexei V; Frieman, Joshua; Fynbo, Johan; Galbany, Lluis; Ganeshalingam, Mohan; Garnavich, Peter M; Graham, Melissa L; Hsiao, Eric Y; Leloudas, Giorgos; Leonard, Douglas C; Li, Weidong; Riess, Adam G; Sako, Masao; Schneider, Donald P; Silverman, Jeffrey M; Sollerman, Jesper; Steele, Thea N; Thomas, Rollin C; Wheeler, J Craig; Zheng, Chen

    2013-01-01

    We present Hubble Space Telescope (HST) and ground-based optical and near-infrared observations of SN 2005hk and SN 2008A, typical members of the Type Iax class of supernovae (SNe). These objects are peculiar cousins of normal Type Ia SNe, with SN 2002cx as the prototype. Here we focus on late-time observations, where these objects deviate most dramatically from normal SNe Ia. Instead of the dominant nebular emission lines that are observed in normal SNe Ia at late phases (and indeed, in SNe of all other types), spectra of SNe 2005hk and 2008A show lines of Fe II, Ca II, and Fe I more than a year past maximum light, along with narrow [Fe II] and [Ca II] emission. We use spectral features to constrain the temperature and density of the ejecta, and find high densities at late times, with n_e >~ 10^9 cm^-3. Such high densities should yield enhanced cooling of the ejecta, making these objects good candidates to observe the expected "infrared catastrophe," a generic feature of SN Ia models. However, our HST photom...

  19. Observation of ozone enhancement in the lower troposphere over East Asia from a space-borne ultraviolet spectrometer

    Science.gov (United States)

    Hayashida, S.; Liu, X.; Ono, A.; Yang, K.; Chance, K.

    2015-09-01

    We report observations from space using ultraviolet (UV) radiance for significant enhancement of ozone in the lower troposphere over central and eastern China (CEC). The recent retrieval products of the Ozone Monitoring Instrument (OMI) onboard the Earth Observing System (EOS) Aura satellite revealed the spatial and temporal variation of ozone distributions in multiple layers in the troposphere. We compared the OMI-derived ozone over Beijing with airborne measurements by the Measurement of Ozone and Water Vapor by Airbus In-Service Aircraft (MOZAIC) program. The correlation between OMI and MOZAIC ozone in the lower troposphere was reasonable, which assured the reliability of OMI ozone retrievals in the lower troposphere under enhanced ozone conditions. The ozone enhancement was clearly observed over CEC, with Shandong Province as its center, and was most notable in June in any given year. Similar seasonal variations were observed throughout the 9-year OMI measurement period of 2005 to 2013. A considerable part of this ozone enhancement could be attributed to the emissions of ozone precursors from industrial activities and automobiles, and possibly from open crop residue burning (OCRB) after the winter wheat harvest. The ozone distribution presented in this study is also consistent with some model studies. The lower tropospheric ozone distribution is first shown from OMI retrieval in this study, and the results will be useful in clarifying any unknown factors that influence ozone distribution by comparison with model simulations.

  20. Analysis of Hubble Space Telescope Observations of an Outburst of Comet 29P/Schwassmann-Wachmann 1

    Science.gov (United States)

    Schambeau, Charles Alfred; Fernandez, Yanga R.; Samarasinha, Nalin H.; Kundu, Arunav

    2016-10-01

    We present results of a continuing analysis on the spin state of the enigmatic Comet 29P/Schwassmann-Wachmann 1 (SW1). Previous works have reported possible constraints on the spin state including a non-principal axis state [1] or a rotation period of tens of days [2]. This diversity of published answers highlights the complexity of determining the spin state of an active comet nucleus. Previous work by our group using 3D Monte Carlo coma modeling of ground-based outburst observations from 2008 [3] has placed constraints on the spin period for a set of assumed spin-pole orientations. Due to the nature of the 2008 outburst morphology no constraints on the spin-pole orientation could be found.We present here an analysis of Hubble Space Telescope WFPC2 observations of SW1 shortly after a 1996 outburst [4] with which we have further constrained the spin state. The 0.046-arcsec/pixel scale (176 km/pixel at SW1) of the PC detector gives an order-of-magnitude improvement in spatial resolution over our ground-based observations. Two sets of observations from UT 1996 Mar. 11.3 and 12.1 show the ejected dust forming an asymmetric outflow contained on the sunward side of the coma. A projected outflow velocity of 0.15 ± 0.02 km/s was measured, similar to our measured value from the 2008 observations. Enhancements of the images were performed [5] to bring out subtle variations in coma brightness (i.e., jets) and to allow us to search for signatures of the nucleus' rotation during the outburst. Three curved features are seen in both sets of observations and were modeled using the 3D Monte Carlo coma model [6]. We find a spin period on the order of several days, in agreement with our earlier 2008 analysis.[1] Meech, K. J., et al.: 1993, Astron. J., 106, 1222. [2] Miles, R., et al.: 2016, Icarus, 272, 327. [3] Schambeau, C. A., et al.: 2016, Icarus, submitted. [4] Feldman, P. D., et al.: 1996, AAS/DPS Meeting Abstracts, 28, 1084. [5] Samarasinha, N. and Larson, S.: 2014, Icarus

  1. Space Telescope and Optical Reverberation Mapping Project. I. Ultraviolet Observations of the Seyfert 1 Galaxy NGC 5548 with the Cosmic Origins Spectrograph on Hubble Space Telescope

    CERN Document Server

    De Rosa, G; Ely, J; Kriss, G A; Crenshaw, D M; Horne, Keith; Korista, K T; Netzer, H; Pogge, R W; Arevalo, P; Barth, A J; Bentz, M C; Brandt, W N; Breeveld, A A; Brewer, B J; Bonta, E Dalla; De Lorenzo-Caceres, A; Denney, K D; Dietrich, M; Edelson, R; Evans, P A; Fausnaugh, M M; Gehrels, N; Gelbord, J M; Goad, M R; Grier, C J; Grupe, D; Hall, P B; Kaastra, J; Kelly, B C; Kennea, J A; Kochanek, C S; Lira, P; Mathur, S; McHardy, I M; Nousek, J A; Pancoast, A; Papadakis, I; Pei, L; Schimoia, J S; Siegel, M; Starkey, D; Treu, T; Uttley, P; Vaughan, S; Vestergaard, M; Villforth, C; Yan, H; Young, S; Zu, Y

    2015-01-01

    We describe the first results from a six-month long reverberation-mapping experiment in the ultraviolet based on 170 observations of the Seyfert 1 galaxy NGC 5548 with the Cosmic Origins Spectrograph on the Hubble Space Telescope. Significant correlated variability is found in the continuum and broad emission lines, with amplitudes ranging from ~30% to a factor of two in the emission lines and a factor of three in the continuum. The variations of all the strong emission lines lag behind those of the continuum, with He II 1640 lagging behind the continuum by ~2.5 days and Lyman alpha 1215, C IV 1550, and Si IV 1400 lagging by ~5-6 days. The relationship between the continuum and emission lines is complex. In particular, during the second half of the campaign, all emission-line lags increased by a factor of 1.3-2 and differences appear in the detailed structure of the continuum and emission-line light curves. Velocity-resolved cross-correlation analysis shows coherent structure in lag versus line-of-sight veloc...

  2. Progress in Space Weather Modeling and Observations Needed to Improve the Operational NAIRAS Model Aircraft Radiation Exposure Predictions

    Science.gov (United States)

    Mertens, C. J.; Kress, B. T.; Wiltberger, M. J.; Tobiska, W.; Xu, X.

    2011-12-01

    The Nowcast of Atmospheric Ionizing Radiation for Aviation Safety (NAIRAS) is a prototype operational model for predicting commercial aircraft radiation exposure from galactic and solar cosmic rays. NAIRAS predictions are currently streaming live from the project's public website, and the exposure rate nowcast is also available on the SpaceWx smartphone app for iPhone, IPad, and Android. Cosmic rays are the primary source of human exposure to high linear energy transfer radiation at aircraft altitudes, which increases the risk of cancer and other adverse health effects. Thus, the NAIRAS model addresses an important national need with broad societal, public health and economic benefits. The processes responsible for the variability in the solar wind, interplanetary magnetic field, solar energetic particle spectrum, and the dynamical response of the magnetosphere to these space environment inputs, strongly influence the composition and energy distribution of the atmospheric ionizing radiation field. During the development of the NAIRAS model, new science questions were identified that must be addressed in order to obtain a more reliable and robust operational model of atmospheric radiation exposure. Addressing these science questions require improvements in both space weather modeling and observations. The focus of this talk is to present these science questions, the proposed methodologies for addressing these science questions, and the anticipated improvements to the operational predictions of atmospheric radiation exposure. The overarching goal of this work is to provide a decision support tool for the aviation industry that will enable an optimal balance to be achieved between minimizing health risks to passengers and aircrew while simultaneously minimizing costs to the airline companies.

  3. Probing seismic solar analogues through observations with the NASA Kepler space telescope and HERMES high-resolution spectrograph

    CERN Document Server

    Beck, P G; García, R A; Nascimento,, J do; Duarte, T S S; Mathis, S; Regulo, C; Ballot, J; Egeland, R; Castro, M; Pérez-Herńandez, F; Creevey, O; Tkachenko, A; van Reeth, T; Bigot, L; Corsaro, E; Metcalfe, T; Mathur, S; Palle, P L; Prieto, C Allende; Montes, D; Johnston, C; Andersen, M F; van Winckel, H

    2016-01-01

    Stars similar to the Sun, known as solar analogues, provide an excellent opportunity to study the preceding and following evolutionary phases of our host star. The unprecedented quality of photometric data collected by the \\Kepler NASA mission allows us to characterise solar-like stars through asteroseismology and study diagnostics of stellar evolution, such as variation of magnetic activity, rotation and the surface lithium abundance. In this project, presented in a series of papers by Salabert et al. (2016a,b) and Beck et al (2016a,b), we investigate the link between stellar activity, rotation, lithium abundance and oscillations in a group of 18 solar-analogue stars through space photometry, obtained with the NASA Kepler space telescope and from currently 50+ hours of ground-based, high-resolution spectroscopy with the Hermes instrument. In these proceedings, we first discuss the selection of the stars in the sample, observations and calibrations and then summarise the main results of the project. By invest...

  4. First simultaneous microlensing observations by two space telescopes: $Spitzer$ & $Swift$ reveal a brown dwarf in event OGLE-2015-BLG-1319

    CERN Document Server

    Shvartzvald, Y; Udalski, A; Gould, A; Sumi, T; Street, R A; Novati, S Calchi; Hundertmark, M; Bozza, V; Beichman, C; Bryden, G; Carey, S; Drummond, J; Fausnaugh, M; Gaudi, B S; Henderson, C B; Tan, T G; Wibking, B; Pogge, R W; Yee, J C; Zhu, W; Tsapras, Y; Bachelet, E; Dominik, M; Bramich, D M; Cassan, A; Jaimes, R Figuera; Horne, K; Ranc, C; Schmidt, R; Snodgrass, C; Wambsganss, J; Steele, I A; Menzies, J; Mao, S; Poleski, R; Pawlak, M; Szymański, M K; Skowron, J; Mróz, P; Kozłowski, S; Wyrzykowski, Ł; Pietrukowicz, P; Soszyński, I; Ulaczyk, K; Abe, F; Asakura, Y; Barry, R K; Bennett, D P; Bhattacharya, A; Bond, I A; Freeman, M; Hirao, Y; Itow, Y; Koshimoto, N; Li, M C A; Ling, C H; Masuda, K; Fukui, A; Matsubara, Y; Muraki, Y; Nagakane, M; Nishioka, T; Ohnishi, K; Oyokawa, H; Rattenbury, N J; Saito, To; Sharan, A; Sullivan, D J; Suzuki, D; Tristram, P J; Yonehara, A; Jørgensen, U G; Burgdorf, M J; Ciceri, S; D'Ago, G; Evans, D F; Hinse, T C; Kains, N; Kerins, E; Korhonen, H; Mancini, L; Popovas, A; Rabus, M; Rahvar, S; Scarpetta, G; Skottfelt, J; Southworth, J; Peixinho, N; Verma, P; Sbarufatti, B; Kennea, J A; Gehrels, N

    2016-01-01

    Simultaneous observations of microlensing events from multiple locations allow for the breaking of degeneracies between the physical properties of the lensing system, specifically by exploring different regions of the lens plane and by directly measuring the "microlens parallax". We report the discovery of a 30-55$M_J$ brown dwarf orbiting a K dwarf in microlensing event OGLE-2015-BLG-1319. The system is located at a distance of $\\sim$5 kpc toward the Galactic bulge. The event was observed by several ground-based groups as well as by $Spitzer$ and $Swift$, allowing the measurement of the physical properties. However, the event is still subject to an 8-fold degeneracy, in particular the well-known close-wide degeneracy, and thus the projected separation between the two lens components is either $\\sim$0.25 AU or $\\sim$45 AU. This is the first microlensing event observed by $Swift$, with the UVOT camera. We study the region of microlensing parameter space to which $Swift$ is sensitive, finding that while for thi...

  5. Multi-band gravitational wave astronomy: science with joint space- and ground-based observations of black hole binaries

    Science.gov (United States)

    Sesana, Alberto

    2017-05-01

    Soon after the observation of the first black hole binary (BHB) by advanced LIGO (aLIGO), GW150914, it was realised that such a massive system would have been observable in the milli-Hz (mHz) band few years prior to coalescence. Operating in the frequency range 0.1-100 mHz, the Laser Interferometer Space Antenna (LISA) can potentially detect up to thousands inspiralling BHBs, based on the coalescence rates inferred from the aLIGO first observing run (O1). The vast majority of them (those emitting at f 10 mHz however, several of them will sweep through the LISA band, eventually producing loud coalescences in the audio-band probed by aLIGO. This contribution reviews the scientific potential of these new class of LISA sources which, in the past few months, has been investigated in several contexts, including multi-messenger and multi-band gravitational wave astronomy, BHB astrophysics, tests of alternative theories of gravity and cosmography.

  6. First Spitzer Space Telescope Observations of Magnetic Cataclysmic Variables: Evidence for Excess Emission at 3--8 microns

    CERN Document Server

    Howell, S B; Hoard, D W; Wachter, S; Harrison, T; Thomas, H C B; Stefaniak, L; Ciardi, D R; Szkody, P; Van Belle, G T; Howell, Steve B.; Brinkworth, Carolyn; Wachter, Stefanie; Harrison, Thomas; Thomas, Howard Chun Beth; Stefaniak, Linda; Ciardi, David R.; Szkody, Paula; Belle, Gerard van

    2006-01-01

    We present the first observations of magnetic cataclysmic variables with the Spitzer Space Telescope. We used the Infrared Array Camera to obtain photometry of the polars EF Eri, GG Leo, V347 Pav, and RX J0154.0-5947 at 3.6, 4.5, 5.8, and 8.0 $\\mu$m. In all of our targets, we detect excess mid-infrared emission over that expected from the component stars alone. We explore the origin of this IR excess by examining bremsstrahlung, cyclotron emission, circumbinary dust, and L/T brown dwarf secondary stars. Bremsstrahlung and cyclotron emission appear unlikely to be significant contributors to the observed fluxes. At present, the most likely candidate for the excess emission is dust that is probably located in a circumbinary disk with an inner temperature near 800 K. However, a simple dust disk plus any reasonable low mass or brown dwarf-like secondary star is unable to fully explain the observed flux densities in the 3--8 $\\mu$m region.

  7. Launch Complex 39 Observation Gantry Area (SWMU# 107) Annual Long-Term Monitoring Report (Year 1) Kennedy Space Center, Florida

    Science.gov (United States)

    Johnson, Jill W.; Towns, Crystal

    2015-01-01

    This document has been prepared by Geosyntec Consultants, Inc. (Geosyntec) to present and discuss the findings of the 2014 and 2015 Long-Term Monitoring (LTM) activities that were completed at the Launch Complex 39 (LC39) Observation Gantry Area (OGA) located at the John F. Kennedy Space Center (KSC), Florida (Site). The remainder of this report includes: (i) a description of the Site location; (ii) summary of Site background and previous investigations; (iii) description of field activities completed as part of the annual LTM program at the Site; (iv) groundwater flow evaluation; (v) presentation and discussion of field and analytical results; and (vi) conclusions and recommendations. Applicable KSC Remediation Team (KSCRT) Meeting minutes are included in Attachment A. This Annual LTM Letter Report was prepared by Geosyntec Consultants (Geosyntec) for NASA under contract number NNK12CA13B, Delivery Order NNK13CA39T project number PCN ENV2188.

  8. Reconfigurable multiport EPON repeater

    Science.gov (United States)

    Oishi, Masayuki; Inohara, Ryo; Agata, Akira; Horiuchi, Yukio

    2009-11-01

    An extended reach EPON repeater is one of the solutions to effectively expand FTTH service areas. In this paper, we propose a reconfigurable multi-port EPON repeater for effective accommodation of multiple ODNs with a single OLT line card. The proposed repeater, which has multi-ports in both OLT and ODN sides, consists of TRs, BTRs with the CDR function and a reconfigurable electrical matrix switch, can accommodate multiple ODNs to a single OLT line card by controlling the connection of the matrix switch. Although conventional EPON repeaters require full OLT line cards to accommodate subscribers from the initial installation stage, the proposed repeater can dramatically reduce the number of required line cards especially when the number of subscribers is less than a half of the maximum registerable users per OLT. Numerical calculation results show that the extended reach EPON system with the proposed EPON repeater can save 17.5% of the initial installation cost compared with a conventional repeater, and can be less expensive than conventional systems up to the maximum subscribers especially when the percentage of ODNs in lightly-populated areas is higher.

  9. Revisiting the TALE repeat.

    Science.gov (United States)

    Deng, Dong; Yan, Chuangye; Wu, Jianping; Pan, Xiaojing; Yan, Nieng

    2014-04-01

    Transcription activator-like (TAL) effectors specifically bind to double stranded (ds) DNA through a central domain of tandem repeats. Each TAL effector (TALE) repeat comprises 33-35 amino acids and recognizes one specific DNA base through a highly variable residue at a fixed position in the repeat. Structural studies have revealed the molecular basis of DNA recognition by TALE repeats. Examination of the overall structure reveals that the basic building block of TALE protein, namely a helical hairpin, is one-helix shifted from the previously defined TALE motif. Here we wish to suggest a structure-based re-demarcation of the TALE repeat which starts with the residues that bind to the DNA backbone phosphate and concludes with the base-recognition hyper-variable residue. This new numbering system is consistent with the α-solenoid superfamily to which TALE belongs, and reflects the structural integrity of TAL effectors. In addition, it confers integral number of TALE repeats that matches the number of bound DNA bases. We then present fifteen crystal structures of engineered dHax3 variants in complex with target DNA molecules, which elucidate the structural basis for the recognition of bases adenine (A) and guanine (G) by reported or uncharacterized TALE codes. Finally, we analyzed the sequence-structure correlation of the amino acid residues within a TALE repeat. The structural analyses reported here may advance the mechanistic understanding of TALE proteins and facilitate the design of TALEN with improved affinity and specificity.

  10. Recursive quantum repeater networks

    CERN Document Server

    Van Meter, Rodney; Horsman, Clare

    2011-01-01

    Internet-scale quantum repeater networks will be heterogeneous in physical technology, repeater functionality, and management. The classical control necessary to use the network will therefore face similar issues as Internet data transmission. Many scalability and management problems that arose during the development of the Internet might have been solved in a more uniform fashion, improving flexibility and reducing redundant engineering effort. Quantum repeater network development is currently at the stage where we risk similar duplication when separate systems are combined. We propose a unifying framework that can be used with all existing repeater designs. We introduce the notion of a Quantum Recursive Network Architecture, developed from the emerging classical concept of 'recursive networks', extending recursive mechanisms from a focus on data forwarding to a more general distributed computing request framework. Recursion abstracts independent transit networks as single relay nodes, unifies software layer...

  11. Multi-wavelength Observations of Photospheric Vortex Flows in the Photosphere Using Ground-based and Space-borne Telescopes

    Science.gov (United States)

    Palacios, J.; Vargas Domínguez, S.; Balmaceda, L. A.; Cabello, I.; Domingo, V.

    2016-04-01

    In this work we follow a series of papers on high-resolution observations of small-scale structures in the solar atmosphere (Balmaceda et al. 2009, 2010; Vargas Domínguez et al. 2011; Palacios et al. 2012; Domingo et al. 2012; Vargas Domínguez et al. 2015, Cabello et al., in prep), combining several multi-wavelength data series. These were acquired by both ground-based (SST) and space-borne (Hinode) instruments during the joint campaign of the Hinode Operation Program 14, in September 2007. Diffraction-limited SST data were taken in the G-band and G-cont, and were restored by the MFBD technique. Hinode instruments, on the other hand, provided multispectral data from SOT-FG in the CN band, and Mg I and Ca II lines, as well as from SOT-SP in the Fe I line. In this series of works we have thoroughly studied vortex flows and their statistical occurrences, horizontal velocity fields by means of Local Correlation Tracking (LCT), divergence and vorticity. Taking advantage of the high-cadence and high spatial resolution data, we have also studied bright point statistics and magnetic field intensification, highlighting the importance of the smallest-scale magnetic element observations.

  12. Infrared-faint radio sources remain undetected at far-infrared wavelengths. Deep photometric observations using the Herschel Space Observatory

    CERN Document Server

    Herzog, Andreas; Middelberg, Enno; Spitler, Lee R; Leipski, Christian; Parker, Quentin A

    2015-01-01

    Showing 1.4 GHz flux densities in the range of a few to a few tens of mJy, infrared-faint radio sources (IFRS) are a type of galaxy characterised by faint or absent near-infrared counterparts and consequently extreme radio-to-infrared flux density ratios up to several thousand. Recent studies showed that IFRS are radio-loud active galactic nuclei (AGNs) at redshifts >=2. This work explores the far-infrared emission of IFRS, providing crucial information on the star forming and AGN activity of IFRS and on the potential link between IFRS and high-redshift radio galaxies (HzRGs). A sample of six IFRS was observed with the Herschel Space Observatory between 100 um and 500 um. Using these results, we constrained the nature of IFRS by modelling their broad-band spectral energy distribution (SED). Furthermore, we set an upper limit on their infrared SED and decomposed their emission into contributions from an AGN and from star forming activity. All six observed IFRS were undetected in all five Herschel far-infrared ...

  13. Mid-Infrared Observations of Normal Star-Forming Galaxies The Infrared Space Observatory Key Project Sample

    CERN Document Server

    Dale, D A; Helou, G; Dale, Daniel A.; Silbermann, Nancy A.; Helou, George

    2000-01-01

    We present mid-infrared maps and preliminary analysis for 61 galaxies observed with the ISOCAM instrument aboard the Infrared Space Observatory. Many of the general features of galaxies observed at optical wavelengths---spiral arms, disks, rings, and bright knots of emission---are also seen in the mid-infrared, except the prominent optical bulges are absent at 6.75 and 15 microns. In addition, the maps are quite similar at 6.75 and 15 microns, except for a few cases where a central starburst leads to lower 6.75/15 ratios in the inner region. We also present infrared flux densities and mid-infrared sizes for these galaxies. The mid-infrared color 6.75/15 shows a distinct trend with the far-infrared color 60/100. The quiescent galaxies in our sample (60/100 < 0.6) show 6.75/15 near unity, whereas this ratio drops significantly for galaxies with higher global heating intensity levels. Azimuthally-averaged surface brightness profiles indicate the extent to which the mid-infrared flux is centrally concentrated,...

  14. Separation of atmospheric, oceanic and hydrological polar motion excitation mechanisms by a combination of geometric and gravimetric space observations

    Science.gov (United States)

    Göttl, Franziska; Schmidt, Michael; Seitz, Florian; Blossfeld, Mathis

    2014-05-01

    Redistribution and motion of masses within and between the individual subsystems of the Earth cause variations of the orientation of the Earth axis with respect to an Earth-fixed reference frame (polar motion and length-of-day variations). Whereas the integral effect of Earth rotation is precisely measured by geometric space techniques, such as Satellite Laser Ranging (SLR), Very Long Baseline Interferometry (VLBI), Global Navigation Satellite Systems (GNSS) and Doppler Orbit determination and Radiopositioning Integrated on Satellite (DORIS), the separation into individual excitation mechanisms remains a challenge. Commonly, individual geophysical excitation mechanisms of Earth rotation are derived from geophysical models. Due to the fact that geophysical models are afflicted with uncertainties, results derived from different model show large discrepancies. Here we present an adjustment model which allows to combine precise observations from space geodetic observation systems (SLR, VLBI, GNSS, DORIS, satellite altimetry and satellite gravimetry) in order to separate geophysical excitation mechanisms of the Earth rotation. Time variable gravity field solutions from GRACE (Gravity Recovery and Climate Experiment) are used to determine not only the integral mass effect but also the oceanic and hydrological mass effects by applying suitable filter techniques and land-ocean-masks. Furthermore the oceanic mass effect is determined from sea level anomalies as observed by cross-calibrated multi-mission altimetry. Due to the fact that sea level anomalies are not only caused by mass variations but also by volume changes (steric effect), these steric sea level anomalies need to be reduced using appropriate models. We show that through the combination weaknesses of the individual processing strategies can be compensated and the technique specific strengths can be optimally accounted for. This way, excitation functions of atmospheric, oceanic and hydrological mass effects and

  15. Determination of Absolute Plate Spacing for the Fabry-Perot Subassembly of the Thermosphere Imager for Global Observations Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Task 1: rad test AD7746 component for failure dosage for use in GEO Task 2: Algorithm for determining absolute plate spacing of the TIGO Fabry-Perot plates,...

  16. GEROS-ISS: Innovative GNSS reflectometry/occultation payload onboard the International Space Station for the Global Geodetic Observing System

    Science.gov (United States)

    Wickert, J.; Andersen, O. B.; Beyerle, G.; Chapron, B.; Cardellach, E.; D'Addio, S.; Foerste, C.; Gommenginger, C.; Gruber, T.; Helm, A.; Hess, M.; Hoeg, P.; Jaeggi, A.; Jakowski, N.; Kern, M.; Lee, T.; Martin-Neira, M.; Montenbruck, O.; Pierdicca, N.; Rius, A.; Rothacher, M.; Shum, C.; Zuffada, C.

    2013-12-01

    In response to a European Space Agency (ESA) announcement of opportunity, the GEROS-ISS proposal was submitted and accepted by ESA to proceed to Phase A. GEROS-ISS is an innovative ISS experiment primarily focused on exploiting reflected signals of opportunity from Global Navigation Satellite Systems (GNSS) at L-band to measure key parameters of ocean and land/ice surfaces. Secondary mission goals are global atmosphere and ionosphere observations using the GNSS radio occultation technique complementing other current satellite missions. GEROS-ISS will pioneer the exploitation of signals from Galileo and possibly other GNSS systems, for reflectometry and occultation, thereby improving the accuracy as well as the spatio-temporal resolution of the derived geophysical properties. GEROS-ISS will contribute to the long-term S.I. traceable observation of the variations of major climate components of the Earth System: Oceans/Hydrosphere, Cryosphere/Snow, Atmosphere/Ionosphere and solid Earth/landcover changes with innovative and complementary aspects compared to current Earth Observation satellite missions. Therefore, the data from GEROS-ISS allow for climate change related scientific studies addressing the challenges of ESA's Earth Observation strategy (SP 1304 The Changing Earth: New scientific challenges for ESA's living planet). GEROS-ISS will mainly provide mid- and low-latitude observations on submesoscale or longer oceanic variability with a focus on the coastal region, surface ocean currents, surface winds, wave heights and the vertical atmospheric temperature, water vapour and electron density structure for a period of at least ten years. These observations will lead to a better understanding of the climate system, including Rossby wave large-scale structures, ocean roughness and wind, eddy-current systems, fronts and coastal upwelling. GEROS-ISS takes advantage of the capacious infrastructure onboard the ISS, to potentially derive additional Earth's surface

  17. The analysis of space time structure in QCD vacuum, I: localization vs global behavior in local observables and Dirac eigenmodes

    Science.gov (United States)

    Horváth, Ivan

    2005-03-01

    The structure of QCD vacuum can be studied from first principles using lattice-regularized theory. This line of research entered a qualitatively new phase recently, wherein the space-time structure (at least for some quantities) can be directly observed in configurations dominating the QCD path integral, i.e., without any subjective processing of typical configurations. This approach to QCD vacuum structure does not rely on any proposed picture of QCD vacuum but rather attempts to characterize this structure in a model-independent manner, so that a coherent physical picture of the vacuum can emerge when such unbiased numerical information accumulates to a sufficient degree. An important part of this program is to develop a set of suitable quantitative characteristics describing the space-time structure in a meaningful and physically relevant manner. One of the basic pertinent issues here is whether QCD vacuum dynamics can be understood in terms of localized vacuum objects, or whether such objects behave as inherently global entities. The first direct studies of vacuum structure strongly support the latter. In this paper, we develop a formal framework which allows to answer this question in a quantitative manner. We discuss in detail how to apply this approach to Dirac eigenmodes and to basic scalar and pseudoscalar composites of gauge fields (action density and topological charge density). The approach is illustrated numerically on overlap Dirac zero modes and near-zero modes. This illustrative data provides direct quantitative evidence supporting our earlier arguments for the global nature of QCD Dirac eigenmodes.

  18. Space Technology 5 (ST-5) Observations of the Imbalance of Region 1 and 2 Field-Aligned Currents

    Science.gov (United States)

    Le, Guan

    2010-01-01

    Space Technology 5 (ST-5) is a three micro-satellite constellation deployed into a 300 x 4500 km, dawn-dusk, sun-synchronous polar orbit from March 22 to June 21, 2006, for technology validations. In this study, we use the in-situ magnetic field observations from Space Technology 5 mission to quantify the imbalance of Region 1 (R1) and Region 2 (R2) currents. During the three-month duration of the ST5 mission, geomagnetic conditions range from quiet to moderately active. We find that the R1 current intensity is consistently stronger than the R2 current intensity both for the dawnside and the duskside large-scale field-aligned current system. The net currents flowing into (out of) the ionosphere in the dawnside (duskside) are in the order of 5% of the total RI currents. We also find that the net currents flowing into or out of the ionosphere are controlled by the solar wind-magnetosphere interaction in the same way as the field-aligned currents themselves are. Since the net currents due to the imbalance of the R1 and R2 currents require that their closure currents flow across the polar cap from dawn to dusk as Pedersen currents, our results indicate that the total amount of the cross-polar cap Pedersen currents is in the order of approx. 0.1 MA. This study, although with a very limited dataset, is one of the first attempts to quantify the cross-polar cap Pedersen currents. Given the importance of the Joule heating due to Pedersen currents to the high-latitude ionospheric electrodynamics, quantifying the cross-polar cap Pedersen currents and associated Joule heating is needed for developing models of the magnetosphere-ionosphere coupling.

  19. Probing Seismic Solar Analogues Through Observations With The NASA Kepler Space Telescope and Hermes High-Resolution Spectrograph

    Science.gov (United States)

    Beck, P. G.; Salabert, D.; Garcia, R. A.; do Nascimento, J., Jr.; Duarte, T. S. S.; Mathis, S.; Regulo, C.; Ballot, J.; Egeland, R.; Castro, M.; Pérez-Herńandez, F.,; Creevey, O.; Tkachenko, A.; van Reeth, T.; Bigot, L.; Corsaro, E.; Metcalfe, T.; Mathur, S.; Palle, P. L.; Allende Prieto, C.; Montes, D.; Johnston, C.; Andersen, M. F.; van Winckel, H.

    2016-11-01

    Stars similar to the Sun, known as solar analogues, provide an excellent opportunity to study the preceding and following evolutionary phases of our host star. The unprecedented quality of photometric data collected by the Kepler NASA mission allows us to characterise solar-like stars through asteroseismology and study diagnostics of stellar evolution, such as variation of magnetic activity, rotation and the surface lithium abundance. In this project, presented in a series of papers by Salabert et al (2016ab) and Beck et al. (2016ab), we investigate the link between stellar activity, rotation, lithium abundance and oscillations in a group of 18 solar-analogue stars through space photometry, obtained with the NASA Kepler space telescope and from currently 50+ hours of ground-based, high-resolution spectroscopy with the Hermes instrument. In these proceedings, we first discuss the selection of the stars in the sample, observations and calibrations and then summarise the main results of the project. By investigating the chromospheric and photospheric activity of the solar analogues in this sample, it was shown that for a large fraction of these stars the measured activity levels are compatible to levels of the 11-year solar activity cycle 23. A clear correlation between the lithium abundance and surface rotation was found for rotation periods shorter than the solar value. Comparing the lithium abundance measured in the solar analogues to evolutionary models with the Toulouse-Geneva Evolutionary Code (TGEC), we found that the solar models calibrated to the Sun also correctly describe the set of solar/stellar analogs showing that they share the same internal mixing physics. Finally, the star KIC3241581 and KIC10644353 are discussed in more detail.

  20. Hubble Space Telescope Observations of the Afterglow, Supernova and Host Galaxy Associated with the Extremely Bright GRB 130427A

    Science.gov (United States)

    Levan, A.J.; Tanvir, N. R.; Fruchter, A. S.; Hjorth, J.; Pian, E.; Mazzali, P.; Hounsell, R. A.; Perley, D. A.; Cano, Z.; Graham, J.; hide

    2014-01-01

    We present Hubble Space Telescope (HST) observations of the exceptionally bright and luminous Swift gamma-ray burst, GRB 130427A. At z=0.34 this burst affords an excellent opportunity to study the supernova and host galaxy associated with an intrinsically extremely luminous burst (E(sub iso) greater than 10(exp 54) erg): more luminous than any previous GRB with a spectroscopically associated supernova. We use the combination of the image quality, UV capability and and invariant PSF of HST to provide the best possible separation of the afterglow, host and supernova contributions to the observed light approximately 17 rest-frame days after the burst utilising a host subtraction spectrum obtained 1 year later. Advanced Camera for Surveys (ACS) grism observations show that the associated supernova, SN 2013cq, has an overall spectral shape and luminosity similar to SN 1998bw (with a photospheric velocity, vph approximately 15,000 kilometers per second). The positions of the bluer features are better matched by the higher velocity SN 2010bh (vph approximately 30,000 kilometers per second), but SN 2010bh (vph approximately 30,000 kilometers per second but this SN is significantly fainter, and fails to reproduce the overall spectral shape, perhaps indicative of velocity structure in the ejecta. We find that the burst originated approximately 4 kpc from the nucleus of a moderately star forming (1 Solar Mass yr(exp-1)), possibly interacting disc galaxy. The absolute magnitude, physical size and morphology of this galaxy, as well as the location of the GRB within it are also strikingly similar to those of GRB980425SN 1998bw. The similarity of supernovae and environment from both the most luminous and least luminous GRBs suggests broadly similar progenitor stars can create GRBs across six orders of magnitude in isotropic energy.