WorldWideScience

Sample records for tohoku-hiroshima-nagoya planetary spectra

  1. Gravitational effects on planetary neutron flux spectra

    Science.gov (United States)

    Feldman, W. C.; Drake, D. M.; O'Dell, R. D.; Brinkley, F. W., Jr.; Anderson, R. C.

    1989-01-01

    The effects of gravity on the planetary neutron flux spectra for planet Mars, and the lifetime of the neutron, were investigated using a modified one-dimensional diffusion accelerated neutral-particle transport code, coupled with a multigroup cross-section library tailored specifically for Mars. The results showed the presence of a qualitatively new feature in planetary neutron leakage spectra in the form of a component of returning neutrons with kinetic energies less than the gravitational binding energy (0.132 eV for Mars). The net effect is an enhancement in flux at the lowest energies that is largest at and above the outermost layer of planetary matter.

  2. Quantitative analysis of planetary reflectance spectra with principal components analysis

    Science.gov (United States)

    Johnson, P. E.; Smith, M. O.; Adams, J. B.

    1985-01-01

    A technique is presented for quantitative analysis of planetary reflectance spectra as mixtures of particles on microscopic and macroscopic scales using principal components analysis. This technique allows for determination of the endmembers being mixed, their abundance, and the scale of mixing, as well as other physical parameters. Eighteen lunar telescopic reflectance spectra of the Copernicus crater region, from 600 nm to 1800 nm in wavelength, are modeled in terms of five likely endmembers: mare basalt, mature mare soil, anorthosite, mature highland soil, and clinopyroxene. These endmembers were chosen from a similar analysis of 92 lunar soil and rock samples. The models fit the data to within 2 percent rms. It is found that the goodness of fit is marginally better for intimate mixing over macroscopic mixing.

  3. Classification of ISO SWS 01 spectra of proto-planetary nebulae: a search for precursors of planetary nebulae with [WR] central stars

    OpenAIRE

    Szczerba, R.; Stasi{ń}ska, G.; Siódmiak, N.; Górny, S. K.

    2002-01-01

    We have analyzed ISO SWS 01 observations for 61 proto-planetary nebulae candidates and classified their spectra according to their dominant chemistry. On the basis of our classification and the more general classification of SWS 01 spectra by Kraemer et al. (2002) we discuss the connection between proto-planetary nebulae candidates and planetary nebulae, with emphasis on possible precursors of planetary nebulae with [WR] central stars.

  4. Fitting the curve in Excel® : Systematic curve fitting of laboratory and remotely sensed planetary spectra

    NARCIS (Netherlands)

    McCraig, M.A.; Osinski, G.R.; Cloutis, E.A.; Flemming, R.L.; Izawa, M.R.M.; Reddy, V.; Fieber-Beyer, S.K.; Pompilio, L.; van der Meer, F.D.; Berger, J.A.; Bramble, M.S.; Applin, D.M.

    2017-01-01

    Spectroscopy in planetary science often provides the only information regarding the compositional and mineralogical make up of planetary surfaces. The methods employed when curve fitting and modelling spectra can be confusing and difficult to visualize and comprehend. Researchers who are new to

  5. Optical and Near-infrared Spectra of σ Orionis Isolated Planetary-mass Objects

    Energy Technology Data Exchange (ETDEWEB)

    Zapatero Osorio, M. R. [Centro de Astrobiología (CSIC-INTA), Crta. Ajalvir km 4, E-28850 Torrejón de Ardoz, Madrid (Spain); Béjar, V. J. S. [Instituto de Astrofísica de Canarias, C/. Vía Láctea s/n, E-38205 La Laguna, Tenerife (Spain); Ramírez, K. Peña, E-mail: mosorio@cab.inta-csic.es, E-mail: vbejar@iac.es, E-mail: karla.pena@uantof.cl [Unidad de Astronomía de la Universidad de Antofagasta, Av. U. de Antofagasta. 02800 Antofagasta (Chile)

    2017-06-10

    We have obtained low-resolution optical (0.7–0.98 μ m) and near-infrared (1.11–1.34 μ m and 0.8–2.5 μ m) spectra of 12 isolated planetary-mass candidates ( J = 18.2–19.9 mag) of the 3 Myr σ Orionis star cluster with the aim of determining the spectroscopic properties of very young, substellar dwarfs and assembling a complete cluster mass function. We have classified our targets by visual comparison with high- and low-gravity standards and by measuring newly defined spectroscopic indices. We derived L0–L4.5 and M9–L2.5 using high- and low-gravity standards, respectively. Our targets reveal clear signposts of youth, thus corroborating their cluster membership and planetary masses (6–13 M {sub Jup}). These observations complete the σ Orionis mass function by spectroscopically confirming the planetary-mass domain to a confidence level of ∼75%. The comparison of our spectra with BT-Settl solar metallicity model atmospheres yields a temperature scale of 2350–1800 K and a low surface gravity of log g ≈ 4.0 [cm s{sup −2}], as would be expected for young planetary-mass objects. We discuss the properties of the cluster’s least-massive population as a function of spectral type. We have also obtained the first optical spectrum of S Ori 70, a T dwarf in the direction of σ Orionis. Our data provide reference optical and near-infrared spectra of very young L dwarfs and a mass function that may be used as templates for future studies of low-mass substellar objects and exoplanets. The extrapolation of the σ Orionis mass function to the solar neighborhood may indicate that isolated planetary-mass objects with temperatures of ∼200–300 K and masses in the interval 6–13 M {sub Jup} may be as numerous as very low-mass stars.

  6. First results from a laboratory facility for measurement of emission spectra under simulated planetary conditions

    Science.gov (United States)

    Lucey, Paul G.; Domergue-Schmidt, Natalie; Henderson, Bradley G.; Jakosky, Bruce

    1993-01-01

    We have developed a laboratory spectroscopic facility for the measurement of emission spectra under simulated planetary conditions. Spectral measurements are made from 6 to 13 microns with a scanning grating monochromator equipped with a HgCdTl detector. An environment chamber in service in Hawaii for several years in which we can control the temperature from 77 K to 500 K, the pressure from 10(exp -5) torr to two atmospheres, has been equipped with a 77 K or 273 K cold shield. The shield serves to minimize light reflected off the sample and to aid in development of thermal gradients for obtaining spectra under conditions simulating the thermal environment of airless bodies. Samples are placed in small cups on a temperature controlled substrate allowing measurements of emission due to heating from below by the substrate, or from illumination from a solar simulation source.

  7. Nebular and auroral emission lines of [Cl III] in the optical spectra of planetary nebulae.

    Science.gov (United States)

    Keenan, F P; Aller, L H; Ramsbottom, C A; Bell, K L; Crawford, F L; Hyung, S

    2000-04-25

    Electron impact excitation rates in Cl III, recently determined with the R-matrix code, are used to calculate electron temperature (T(e)) and density (N(e)) emission line ratios involving both the nebular (5517.7, 5537.9 A) and auroral (8433.9, 8480.9, 8500.0 A) transitions. A comparison of these results with observational data for a sample of planetary nebulae, obtained with the Hamilton Echelle Spectrograph on the 3-m Shane Telescope, reveals that the R(1) = I(5518 A)/I(5538 A) intensity ratio provides estimates of N(e) in excellent agreement with the values derived from other line ratios in the echelle spectra. This agreement indicates that R(1) is a reliable density diagnostic for planetary nebulae, and it also provides observational support for the accuracy of the atomic data adopted in the line ratio calculations. However the [Cl iii] 8433.9 A line is found to be frequently blended with a weak telluric emission feature, although in those instances when the [Cl iii] intensity may be reliably measured, it provides accurate determinations of T(e) when ratioed against the sum of the 5518 and 5538 A line fluxes. Similarly, the 8500.0 A line, previously believed to be free of contamination by the Earth's atmosphere, is also shown to be generally blended with a weak telluric emission feature. The [Cl iii] transition at 8480.9 A is found to be blended with the He i 8480.7 A line, except in planetary nebulae that show a relatively weak He i spectrum, where it also provides reliable estimates of T(e) when ratioed against the nebular lines. Finally, the diagnostic potential of the near-UV [Cl iii] lines at 3344 and 3354 A is briefly discussed.

  8. Optical Spectra of Radio Planetary Nebulae in the Large Magellanic Cloud

    Directory of Open Access Journals (Sweden)

    Payne, J. L.

    2008-12-01

    Full Text Available We present 11 spectra from 12 candidate radio sources co-identified with known planetary nebulae (PNe in the Large Magellanic Cloud (LMC. Originally found in Australia Telescope Compact Array (ATCA LMC surveys at 1.4, 4.8 and 8.64~GHz and confirmed by new high resolution ATCA images at 6 and 3~cm (4arcsec/2arcsec, these complement data recently presented for candidate radio PNe in the Small Magellanic Cloud (SMC. Their spectra were obtained using the Radcliffe 1.9-meter telescope in Sutherland (South Africa. All of the optical PNe and radio candidates are within 2arcsec and may represent a population of selected radio bright sample only. Nebular ionized masses of these objects are estimated to be as high as 1.8~$M_odot$, supporting the idea that massive PNe progenitor central stars lose much of their mass in the asymptotic giant branch (AGB phase or prior. We also identify a sub-population (33\\% of radio PNe candidates with prominent ionized iron emission lines.

  9. Optical spectra of radio planetary nebulae in the large Magellanic Cloud

    Directory of Open Access Journals (Sweden)

    Payne J.L.

    2008-01-01

    Full Text Available We present 11 spectra from 12 candidate radio sources co-identified with known planetary nebulae (PNe in the Large Magellanic Cloud (LMC. Originally found in Australia Telescope Compact Array (ATCA LMC surveys at 1.4, 4.8 and 8.64 GHz and confirmed by new high resolution ATCA images at 6 and 3 cm (4' /2' , these complement data recently presented for candidate radio PNe in the Small Magellanic Cloud (SMC. Their spectra were obtained using the Radcliff 1.9-meter telescope in Sutherland (South Africa. All of the optical PNe and radio candidates are within 2' and may represent a population of selected radio bright sample only. Nebular ionized masses of these objects are estimated to be as high as 1.8 Mfi, supporting the idea that massive PNe progenitor central stars lose much of their mass in the asymptotic giant branch (AGB phase or prior. We also identify a sub-population (33% of radio PNe candidates with prominent ionized iron emission lines.

  10. Emission Lines of O III in The Optical and Ultraviolet Spectra of Planetary Nebulae

    Science.gov (United States)

    Crawford, F. L.; Keenan, F. P.; Aggarwal, K. M.; Aller, L. H.; Feibelman, W. A.; Fisher, Richard R. (Technical Monitor)

    2000-01-01

    Recent R-matrix calculations of electron impact excitation rates in 0 III are used to calculate electron temperature and density-dependent emission line ratios R (sub 1) = I(4363 Angstroms)/ I(4960 Angstroms + 5007 Angstroms), R (sub 2) = I(1661 Angstroms + 1667 Angstroms)/ I(4960 Angstroms + 5007 Angstroms) and R (sub 3)= I(2322 Angstroms)/ I(1661 Angstroms + 1667 Angstroms), for a range of electron temperatures (7500 less than or equal to Te less than or equal to 30 000 K) and densities (10 (exp 4) less than or equal to N (sub e) less than or equal to 10 (exp 7) per cubic centimeters) applicable to gaseous nebulae. The ratio-ratio diagrams (R (sub 1), R (sub 2)) and (R (sub 1), R (sub 3)) should, in principle, allow the simultaneous determination of T (sub e) and N (sub e) from measurements of the 0 III features in a spectrum. Plasma parameters derived for a sample of high-excitation planetary nebulae from (R (sub 1), R (sub 2)) and (R (sub 1), R (sub 3)) measurements, produced using a combination of ultraviolet spectra obtained with the International Ultraviolet Explorer (IUE) and optical data from a number of observing runs, are found to show excellent internal consistency. They also show, in general, good agreement with the values of Te and Ne estimated from other line ratios in the nebulae, therefore providing observational support for the accuracy of the theoretical ratios and hence the atomic data adopted in their derivation.

  11. Near-surface thermal gradients and their effects on mid-infrared emission spectra of planetary surfaces

    Science.gov (United States)

    Henderson, B. G.; Jakosky, B. M.

    1994-01-01

    We model the heat transfer by radiation and conduction in the top few millimeters of a planetary surface to determine the magnitude of near-surface (approximately 100 micrometers) thermal gradients and their effects on mid-infrared emission spectra for a number of planetary environments. The model is one-dimensional and uses a finite difference scheme for approximately 10 micrometers layers. Calculations are peformed for samples heated at the base and from above by sunlight. Our results indicate that near-surface radiative cooling creates significant thermal gradients in the top few hundred microns of surfaces in which radiation is an importamnt heat transfer mechanism. The effect is maximized in evacuated, underdense particulate media with sufficiently high temperatures. Near-surface thermal gradients will be significant in fine-grained particulate surfaces on the Moon (40-60 K/100 micrometers) and Mercury (approximately 80 K/100 micrometers), increasing spectral contrast and creating emission maxima in the transparent regions of the spectra. They will be of lesser importance on the surface of Mars, with a maximum value of around 5 k/100 micrometers in areas of low thermal inertia, and will be negligible on planets with more substantial atmospheres (less than 1 K/100 micrometers). We conclude that the effects that thermal gradients have on mid-IR emission spectra are predictable and do not negate the utility of emission spectroscopy for remote determination of planetary surface composition.

  12. Fitting the curve in Excel®: Systematic curve fitting of laboratory and remotely sensed planetary spectra

    Science.gov (United States)

    McCraig, Michael A.; Osinski, Gordon R.; Cloutis, Edward A.; Flemming, Roberta L.; Izawa, Matthew R. M.; Reddy, Vishnu; Fieber-Beyer, Sherry K.; Pompilio, Loredana; van der Meer, Freek; Berger, Jeffrey A.; Bramble, Michael S.; Applin, Daniel M.

    2017-03-01

    Spectroscopy in planetary science often provides the only information regarding the compositional and mineralogical make up of planetary surfaces. The methods employed when curve fitting and modelling spectra can be confusing and difficult to visualize and comprehend. Researchers who are new to working with spectra may find inadequate help or documentation in the scientific literature or in the software packages available for curve fitting. This problem also extends to the parameterization of spectra and the dissemination of derived metrics. Often, when derived metrics are reported, such as band centres, the discussion of exactly how the metrics were derived, or if there was any systematic curve fitting performed, is not included. Herein we provide both recommendations and methods for curve fitting and explanations of the terms and methods used. Techniques to curve fit spectral data of various types are demonstrated using simple-to-understand mathematics and equations written to be used in Microsoft Excel® software, free of macros, in a cut-and-paste fashion that allows one to curve fit spectra in a reasonably user-friendly manner. The procedures use empirical curve fitting, include visualizations, and ameliorates many of the unknowns one may encounter when using black-box commercial software. The provided framework is a comprehensive record of the curve fitting parameters used, the derived metrics, and is intended to be an example of a format for dissemination when curve fitting data.

  13. Modelling Velocity Spectra in the Lower Part of the Planetary Boundary Layer

    DEFF Research Database (Denmark)

    Olesen, H.R.; Larsen, Søren Ejling; Højstrup, Jørgen

    1984-01-01

    Principles used when constructing models for velocity spectra are reviewed. Based upon data from the Kansas and Minnesota experiments, simple spectral models are set up for all velocity components in stable air at low heights, and for the vertical spectrum in unstable air through a larger part of...

  14. Spectra of 5261 Eureka and its family: meteorite spectral analogues of asteroidal and planetary origin

    NARCIS (Netherlands)

    Lim, Lucy F.; Emery, Joshua P.; Mueller, Michael; Rivkin, Andrew S.; Thomas, Cristina A.; Trilling, David E.

    2017-01-01

    The Mars trojan asteroid (5261) Eureka is now known to be the largest member of a dynamical family whose near-IR spectra are dominated by the 1-micron band of olivine (Christou et al. 2013, Ćuk et al. 2015, Borisov et al. 2017, Christou et al. 2017). Recently, Polishook et al. (2017) have suggested

  15. Optical Spectra of Radio Planetary Nebulae in the Small Magellanic Cloud

    Directory of Open Access Journals (Sweden)

    Payne, J. L.

    2008-06-01

    Full Text Available We present preliminary results from spectral observations of four (4 candidate radio sources co-identified with known planetary nebulae (PNe in the Small Magellanic Cloud (SMC. These were made using the Radcliffe 1.9-meter telescope in Sutherland, South Africa. These radio PNe were originally found in Australia Telescope Compact Array (ATCA surveys of the SMC at 1.42 and 2.37~GHz, and were further confirmed by new high resolution ATCA images at 6 and 3 cm (4arcsec/2arcsec. Optical PNe and radio candidates are within 2arcsec and may represent a sub-population of selected radio bright objects. Nebular ionized masses of these objects may be 2.6~$M_odot$ or greater, supporting the existence of PNe progenitor central stars with masses up to 8 $M_odot$.

  16. Optical spectra of radio planetary nebulae in the small Magellanic cloud

    Directory of Open Access Journals (Sweden)

    Payne J.L.

    2008-01-01

    Full Text Available We present preliminary results from spectral observations of four (4 candidate radio sources co-identified with known planetary nebulae (PNe in the Small Magellanic Cloud (SMC. These were made using the Radcliffe 1.9-meter telescope in Sutherland, South Africa. These radio PNe were originally found in Australia Telescope Compact Array (ATCA surveys of the SMC at 1.42 and 2.37 GHz, and were further confirmed by new high resolution ATCA images at 6 and 3 cm (400 /200 . Optical PNe and radio candidates are within 200 and may represent a sub- population of selected radio bright objects. Nebular ionized masses of these objects may be 2.6 Mo or greater, supporting the existence of PNe progenitor central stars with masses up to 8 Mo.

  17. A systematic retrieval analysis of secondary eclipse spectra. III. Diagnosing chemical disequilibrium in planetary atmospheres

    Energy Technology Data Exchange (ETDEWEB)

    Line, Michael R.; Yung, Yuk L., E-mail: mrl@gps.caltech.edu [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125 (United States)

    2013-12-10

    Chemical disequilibrium has recently become a relevant topic in the study of the atmospheres of transiting extrasolar planets, brown dwarfs, and directly imaged exoplanets. We present a new way of assessing whether or not a Jovian-like atmosphere is in chemical disequilibrium from observations of detectable or inferred gases such as H{sub 2}O, CH{sub 4}, CO, and H{sub 2}. Our hypothesis, based on previous kinetic modeling studies, is that cooler atmospheres will show stronger signs of disequilibrium than hotter atmospheres. We verify this with chemistry-transport models and show that planets with temperatures less than ∼1200 K are likely to show the strongest signs of disequilibrium due to the vertical quenching of CO, and that our new approach is able to capture this process. We also find that in certain instances a planetary composition may appear in equilibrium when it actually is not due to the degeneracy in the shape of the vertical mixing ratio profiles. We determine the state of disequilibrium in eight exoplanets using the results from secondary eclipse temperature and abundance retrievals. We find that all of the planets in our sample are consistent with thermochemical equilibrium to within 3σ. Future observations are needed to further constrain the abundances in order to definitively identify disequilibrium in exoplanet atmospheres.

  18. Strong scintillations during atmospheric occultations Theoretical intensity spectra. [radio scattering during spacecraft occultations by planetary atmospheres

    Science.gov (United States)

    Hinson, D. P.

    1986-01-01

    Each of the two Voyager spacecraft launched in 1977 has completed a reconnaissance of the Jovian and Saturnian systems. In connection with occultation experiments, strong scintillations were observed. Further theoretical work is required before these scintillations can be interpreted. The present study is, therefore, concerned with the derivation of a theory for strong scattering during atmospheric occultation experiments, taking into account as fundamental quantity of interest the spatial spectrum (or spectral density) of intensity fluctuations. Attention is given to a theory for intensity spectra, and numerical calculations. The new formula derived for Phi-i accounts for strong scattering of electromagnetic waves during atmospheric occultations.

  19. Analysis of Co-spatial UV-optical HST/STIS Spectra of Planetary Nebula NGC 3242

    Science.gov (United States)

    Miller, Timothy R.; Henry, Richard B. C.; Balick, Bruce; Kwitter, Karen B.; Dufour, Reginald J.; Shaw, Richard A.; Corradi, Romano L. M.

    2016-10-01

    This project sought to consider two important aspects of the planetary nebula NGC 3242 using new long-slit HST/STIS spectra. First, we investigated whether this object is chemically homogeneous by spatially dividing the slit into different regions and calculating the abundances of each region. The major result is that the elements of He, C, O, and Ne are chemically homogeneous within uncertainties across the regions probed, implying that the stellar outflow was well-mixed. Second, we constrained the stellar properties using photoionization models computed by CLOUDY and tested the effects of three different density profiles on these parameters. The three profiles tested were a constant density profile, a Gaussian density profile, and a Gaussian with a power-law density profile. The temperature and luminosity were not affected significantly by the choice of density structure. The values for the stellar temperature and luminosity from our best-fit model are {89.7}-4.7+7.3 kK and log(L/L ⊙) = {3.36}-0.22+0.28, respectively. Comparing to evolutionary models on an HR diagram, this corresponds to an initial and final mass of {0.95}-0.09+0.35{M}⊙ and {0.56}-0.01+0.01{M}⊙ , respectively. 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, Incorporated, under NASA contract NAS5-26555.

  20. Newly Discovered Silicate Features in the Spectra of Young Warm Debris Disks: Probing Terrestrial Regions of Planetary Systems

    Science.gov (United States)

    Ballering, N.; Rieke, G.

    2014-03-01

    Terrestrial planets form by the collisional accretion of planetesimals during the first 100 Myr of a system’s lifetime. For most systems, the terrestrial regions are too near their host star to be directly seen with high-contrast imaging (e.g. with HST, MagAO, or LBTI) and too warm to be imaged with submillimeter interferometers (e.g. ALMA). Mid-infrared excess spectra—originating from the thermal emission of the circumstellar dust leftover from these collisions—remain the best data to constrain the properties of the debris in these regions. The spectra of most debris disks are featureless, taking the shape of (modified) blackbodies. Determining the properties of debris disks with featureless spectra is complicated by a degeneracy between the grain size and location (large grains near the star and small grains farther from the star may be indistinguishable). Debris disk spectra that exhibit solid state emission features allow for a more accurate determination of the dust size and location (e.g. Chen et al. 2006; Olofsson et al. 2012). Such features probe small, warm dust grains in the inner regions of these systems where terrestrial planet formation may be proceeding (Lisse et al. 2009). We report here a successful search for such features. We identified our targets with a preliminary search for signs of emission features in the Spitzer IRS spectra of a number of young early type stars known to harbor warm debris disks. We fit to each target a physically-motivated model spectrum consisting of the sum of the stellar photosphere (modeled as a blackbody) and thermal emission from two dust belts. Each belt was defined by 6 parameters: the inner and outer orbital radii (rin and rout), the index of the radial surface density power law (rexp), the minimum and maximum grain sizes (amin and amax), and the index of the grain size distribution power law (aexp). aexp was fixed to -3.65 and amax was fixed to 1000 μm for all models; all other parameters were allowed to

  1. Near-surface temperature gradients and their effects on thermal-infrared emission spectra of particulate planetary surfaces

    Science.gov (United States)

    Henderson, B. G.; Jakosky, B. M.

    1993-01-01

    The infrared energy emitted from a planetary surface is generated within a finite depth determined by the material's absorption skin depth. This parameter varies significantly with wavelength in the infrared but has an average value of around 50 microns for most geologic materials. In solid rock, heat transfer is efficient enough so that this 50 micron zone of the near surface from which the radiation emanates will be more or less isothermal. In particulate materials, however, heat transfer is more complicated and occurs via a combination of mechanisms, including solid conduction within grains and across grain contacts, conduction through the interstitial gas, and thermal radiation within individual particles and across the void spaces in between grains. On planets with substantial atmospheres, the gas component dominates the heat transfer and tends to mitigate near-surface thermal gradients. However, on airless bodies, the gas component is absent and heat transfer occurs via solid conductions and radiation. If the particles are small relative to the average absorption skin depth, then the top 50-100 microns or so of the surface will be cooled by radiation to space allowing the creation of significant near-surface thermal gradients. In those regions of the spectrum where the absorption coefficient is low, the emission will come from the deeper, warmer parts of the medium, whereas in regions of high absorption, the emission will emanate from shallower, cooler parts of the medium. The resulting emission spectrum will show non-compositional features as a result of the thermal structure in the material. We have modeled the heat transfer in a particulate medium in order to determine the magnitude of near-surface thermal gradients for surfaces on airless bodies and on Mars. We use the calculated thermal structure to determine the effects it has on the infrared emission spectrum of the surface.

  2. Planetary nebulae

    International Nuclear Information System (INIS)

    Amnuehl', P.R.

    1985-01-01

    The history of planetary nebulae discovery and their origin and evolution studies is discussed in a popular way. The problem of planetary nebulae central star is considered. The connection between the white-draft star and the planetary nebulae formulation is shown. The experimental data available acknowledge the hypothesis of red giant - planetary nebula nucleus - white-draft star transition process. Masses of planetary nebulae white-draft stars and central stars are distributed practically similarly: the medium mass is close to 0.6Msub(Sun) (Msub(Sun) - is the mass of the Sun)

  3. Abundances in planetary nebulae : Hb 5

    NARCIS (Netherlands)

    Pottasch, S. R.; Surendiranath, R.

    The ISO spectra of the bilobal planetary nebula Hb 5 are presented. These spectra are combined with the spectra in the visual wavelength region to obtain a complete, extinction corrected, spectrum. The chemical composition of the nebula is then calculated in several ways. First by directly

  4. Planetary Magnetism

    Science.gov (United States)

    Connerney, J. E. P.

    2007-01-01

    The chapter on Planetary Magnetism by Connerney describes the magnetic fields of the planets, from Mercury to Neptune, including the large satellites (Moon, Ganymede) that have or once had active dynamos. The chapter describes the spacecraft missions and observations that, along with select remote observations, form the basis of our knowledge of planetary magnetic fields. Connerney describes the methods of analysis used to characterize planetary magnetic fields, and the models used to represent the main field (due to dynamo action in the planet's interior) and/or remnant magnetic fields locked in the planet's crust, where appropriate. These observations provide valuable insights into dynamo generation of magnetic fields, the structure and composition of planetary interiors, and the evolution of planets.

  5. Optical observations of southern planetary nebula candidates

    NARCIS (Netherlands)

    VandeSteene, GC; Sahu, KC; Pottasch, [No Value

    1996-01-01

    We present H alpha+[NII] images and low resolution spectra of 16 IRAS-selected, southern planetary nebula candidates previously detected in the radio continuum. The H alpha+[NII] images are presented as finding charts. Contour plots are shown for the resolved planetary nebulae. From these images

  6. Planetary Magnetism

    International Nuclear Information System (INIS)

    Russell, C.T.

    1980-01-01

    Planetary spacecraft have now probed the magnetic fields of all the terrestrial planets, the moon, Jupiter, and Saturn. These measurements reveal that dynamos are active in at least four of the planets, Mercury, the earth, Jupiter, and Saturn but that Venus and Mars appear to have at most only very weak planetary magnetic fields. The moon may have once possessed an internal dynamo, for the surface rocks are magnetized. The large satellites of the outer solar system are candidates for dynamo action in addition to the large planets themselves. Of these satellites the one most likely to generate its own internal magnetic field is Io

  7. Planetary Rings

    Science.gov (United States)

    Tiscareno, Matthew S.

    Planetary rings are the only nearby astrophysical disks and the only disks that have been investigated by spacecraft (especially the Cassini spacecraft orbiting Saturn). Although there are significant differences between rings and other disks, chiefly the large planet/ring mass ratio that greatly enhances the flatness of rings (aspect ratios as small as 10- 7), understanding of disks in general can be enhanced by understanding the dynamical processes observed at close range and in real time in planetary rings.We review the known ring systems of the four giant planets, as well as the prospects for ring systems yet to be discovered. We then review planetary rings by type. The A, B, and C rings of Saturn, plus the Cassini Division, comprise our solar system's only dense broad disk and host many phenomena of general application to disks including spiral waves, gap formation, self-gravity wakes, viscous overstability and normal modes, impact clouds, and orbital evolution of embedded moons. Dense narrow rings are found both at Uranus (where they comprise the main rings entirely) and at Saturn (where they are embedded in the broad disk) and are the primary natural laboratory for understanding shepherding and self-stability. Narrow dusty rings, likely generated by embedded source bodies, are surprisingly found to sport azimuthally confined arcs at Neptune, Saturn, and Jupiter. Finally, every known ring system includes a substantial component of diffuse dusty rings.Planetary rings have shown themselves to be useful as detectors of planetary processes around them, including the planetary magnetic field and interplanetary impactors as well as the gravity of nearby perturbing moons. Experimental rings science has made great progress in recent decades, especially numerical simulations of self-gravity wakes and other processes but also laboratory investigations of coefficient of restitution and spectroscopic ground truth. The age of self-sustained ring systems is a matter of

  8. High dispersion spectra for planetary nebula studies

    OpenAIRE

    Lawrence H. Aller; Siek Hyung

    2002-01-01

    Mapas de alta resoluci on en radio, im agenes directas con el Telescopio Espacial Hubble y observaciones con grandes telescopios con optica adaptiva muestran que las nebulosas planetarias tienen formas extremadamente complicadas y son muy diferentes de la simplicidad con que se las imaginaba tiempo atr as. Para atender este problema, uno debe obtener espectros con alta resoluci on espacial y alta dispersi on. Tambi en se requieren largos tiempos de exposiciones, a un con telescop...

  9. Spectral Feature Analysis of Minerals and Planetary Surfaces in an Introductory Planetary Science Course

    Science.gov (United States)

    Urban, Michael J.

    2013-01-01

    Using an ALTA II reflectance spectrometer, the USGS digital spectral library, graphs of planetary spectra, and a few mineral hand samples, one can teach how light can be used to study planets and moons. The author created the hands-on, inquiry-based activity for an undergraduate planetary science course consisting of freshman to senior level…

  10. Planetary Society

    Science.gov (United States)

    Murdin, P.

    2000-11-01

    Carl Sagan, Bruce Murray and Louis Friedman founded the non-profit Planetary Society in 1979 to advance the exploration of the solar system and to continue the search for extraterrestrial life. The Society has its headquarters in Pasadena, California, but is international in scope, with 100 000 members worldwide, making it the largest space interest group in the world. The Society funds a var...

  11. Planetary atomspheres

    International Nuclear Information System (INIS)

    Lal, D.; Rao, M.N.

    1986-01-01

    Salient features of the atmosheres of Venus and Mars are described and compared with those of the earth. Their temperature profiles are given. Degassing of planetary interiors by volcanic and plate tectonic processes is described. Noble gas abundances in the atmospheres of these planets are compared. Information provided by Pioneer, Venera space probes and the Viking-landers on Mars is studied. (B.G.W.)

  12. Planetary engineering

    Science.gov (United States)

    Pollack, James B.; Sagan, Carl

    1991-01-01

    Assuming commercial fusion power, heavy lift vehicles and major advances in genetic engineering, the authors survey possible late-21st century methods of working major transformations in planetary environments. Much more Earthlike climates may be produced on Mars by generating low freezing point greenhouse gases from indigenous materials; on Venus by biological conversion of CO2 to graphite, by canceling the greenhouse effect with high-altitude absorbing fine particles, or by a sunshield at the first Lagrangian point; and on Titan by greenhouses and/or fusion warming. However, in our present state of ignorance we cannot guarantee a stable endstate or exclude unanticipated climatic feedbacks or other unintended consequences. Moreover, as the authors illustrate by several examples, many conceivable modes of planetary engineering are so wasteful of scarce solar system resources and so destructive of important scientific information as to raise profound ethical issues, even if they were economically feasible, which they are not. Global warming on Earth may lead to calls for mitigation by planetary engineering, e.g., emplacement and replenishment of anti-greenhouse layers at high altitudes, or sunshields in space. But here especially we must be concerned about precision, stability, and inadvertent side-effects. The safest and most cost-effective means of countering global warming - beyond, e.g., improved energy efficiency, CFC bans and alternative energy sources - is the continuing reforestation of approximately 2 times 107 sq km of the Earth's surface. This can be accomplished with present technology and probably at the least cost.

  13. Planetary engineering

    Science.gov (United States)

    Pollack, James B.; Sagan, Carl

    Assuming commercial fusion power, heavy lift vehicles and major advances in genetic engineering, the authors survey possible late-21st century methods of working major transformations in planetary environments. Much more Earthlike climates may be produced on Mars by generating low freezing point greenhouse gases from indigenous materials; on Venus by biological conversion of CO2 to graphite, by canceling the greenhouse effect with high-altitude absorbing fine particles, or by a sunshield at the first Lagrangian point; and on Titan by greenhouses and/or fusion warming. However, in our present state of ignorance we cannot guarantee a stable endstate or exclude unanticipated climatic feedbacks or other unintended consequences. Moreover, as the authors illustrate by several examples, many conceivable modes of planetary engineering are so wasteful of scarce solar system resources and so destructive of important scientific information as to raise profound ethical issues, even if they were economically feasible, which they are not. Global warming on Earth may lead to calls for mitigation by planetary engineering, e.g., emplacement and replenishment of anti-greenhouse layers at high altitudes, or sunshields in space. But here especially we must be concerned about precision, stability, and inadvertent side-effects. The safest and most cost-effective means of countering global warming - beyond, e.g., improved energy efficiency, CFC bans and alternative energy sources - is the continuing reforestation of approximately 2 times 107 sq km of the Earth's surface. This can be accomplished with present technology and probably at the least cost.

  14. Planetary geology

    CERN Document Server

    Gasselt, Stephan

    2018-01-01

    This book provides an up-to-date interdisciplinary geoscience-focused overview of solid solar system bodies and their evolution, based on the comparative description of processes acting on them. Planetary research today is a strongly multidisciplinary endeavor with efforts coming from engineering and natural sciences. Key focal areas of study are the solid surfaces found in our Solar System. Some have a direct interaction with the interplanetary medium and others have dynamic atmospheres. In any of those cases, the geological records of those surfaces (and sub-surfaces) are key to understanding the Solar System as a whole: its evolution and the planetary perspective of our own planet. This book has a modular structure and is divided into 4 sections comprising 15 chapters in total. Each section builds upon the previous one but is also self-standing. The sections are:  Methods and tools Processes and Sources  Integration and Geological Syntheses Frontiers The latter covers the far-reaching broad topics of exo...

  15. Shaping of planetary nebulae

    International Nuclear Information System (INIS)

    Balick, B.

    1987-01-01

    The phases of stellar evolution and the development of planetary nebulae are examined. The relation between planetary nebulae and red giants is studied. Spherical and nonspherical cases of shaping planetaries with stellar winds are described. CCD images of nebulae are analyzed, and it is determined that the shape of planetary nebulae depends on ionization levels. Consideration is given to calculating the distances of planetaries using radio images, and molecular hydrogen envelopes which support the wind-shaping model of planetary nebulae

  16. Planetary compositions

    International Nuclear Information System (INIS)

    Taylor, S.R.

    1988-01-01

    The present study of the density, major-element and trace-element compositions, oxygen isotopes, and noble gases of the metal, sulfide, and silicate components of meteorites shows that these properties do not match those of the terrestrial planets, and thereby suggests that there was not much lateral mixing in the solar nebula during planetary accretion. The planets would then have accumulated from narrow concentric zones, and the current zonal structure of the asteroid belt may be analogous to the structure of the inner portions of the solar nebula during the terrestrial planets' accretion. Localized heating during the material's infall to the median plane of the nebula is suggested to have occurred. 64 references

  17. Optical observations of planetary nebula candidates from the northern hemisphere

    NARCIS (Netherlands)

    VandeSteene, GC; Jacoby, GH; Pottasch, [No Value

    We present H alpha+[N II] images of 17 and low resolution spectra of 14 IRAS-selected planetary nebula candidates. The H alpha+[N II] images are presented as finding charts. Contour plots are shown for the resolved planetary nebulae. From these images accurate optical positions and mean optical

  18. Chemical composition of planetary nebulae : Including ISO results

    NARCIS (Netherlands)

    Pottasch, [No Value; Beintema, DA; Salas, JB; Feibelman, WA; Henney, WJ; Franco, J; Martos, M; Pena, M

    2002-01-01

    The method of determining abundances using Infrared Space Observatory spectra is discussed. The results for seven planetary nebula are given. Using these data, a preliminary discussion of their evolution is given.

  19. Planetary Data System (PDS)

    Data.gov (United States)

    National Aeronautics and Space Administration — The Planetary Data System (PDS) is an archive of data products from NASA planetary missions, which is sponsored by NASA's Science Mission Directorate. We actively...

  20. Proto-planetary nebulae

    International Nuclear Information System (INIS)

    Zuckerman, B.

    1978-01-01

    A 'proto-planetary nebula' or a 'planetary nebula progenitor' is the term used to describe those objects that are losing mass at a rate >approximately 10 -5 Msolar masses/year (i.e. comparable to mass loss rates in planetary nebulae with ionized masses >approximately 0.2 Msolar masses) and which, it is believed, will become planetary nebulae themselves within 5 years. It is shown that most proto-planetary nebulae appear as very red objects although a few have been 'caught' near the middle of the Hertzsprung-Russell diagram. The precursors of these proto-planetaries are the general red giant population, more specifically probably Mira and semi-regular variables. (Auth.)end

  1. Escape from planetary neighbourhoods

    NARCIS (Netherlands)

    Waalkens, H.; Burbanks, A.; Wiggins, S.

    2005-01-01

    In this paper we use recently developed phase-space transport theory coupled with a so-called classical spectral theorem to develop a dynamically exact and computationally efficient procedure for studying escape from a planetary neighbourhood. The ‘planetary neighbourhood’ is a bounded region of

  2. Dust in planetary nebulae

    International Nuclear Information System (INIS)

    Kwok, S.

    1980-01-01

    A two-component dust model is suggested to explain the infrared emission from planetary nebulae. A cold dust component located in the extensive remnant of the red-giant envelope exterior to the visible nebula is responsible for the far-infrared emission. A ward dust component, which is condensed after the formation of the planetary nebula and confined within the ionized gas shell, emits most of the near- and mid-infrared radiation. The observations of NGC 7027 are shown to be consisten with such a model. The correlation of silicate emission in several planetary nebulae with an approximately +1 spectral index at low radio frequencies suggests that both the silicate and radio emissions originate from the remnant of the circumstellar envelope of th precursor star and are observable only while the planetary nebula is young. It is argued that oxygen-rich stars as well as carbon-rich stars can be progenitors of planetary nebulae

  3. Planetary Atmospheric Electricity

    CERN Document Server

    Leblanc, F; Yair, Y; Harrison, R. G; Lebreton, J. P; Blanc, M

    2008-01-01

    This volume presents our contemporary understanding of atmospheric electricity at Earth and in other solar system atmospheres. It is written by experts in terrestrial atmospheric electricity and planetary scientists. Many of the key issues related to planetary atmospheric electricity are discussed. The physics presented in this book includes ionisation processes in planetary atmospheres, charge generation and separation, and a discussion of electromagnetic signatures of atmospheric discharges. The measurement of thunderstorms and lightning, including its effects and hazards, is highlighted by articles on ground and space based instrumentation, and new missions.Theory and modelling of planetary atmospheric electricity complete this review of the research that is undertaken in this exciting field of space science. This book is an essential research tool for space scientists and geoscientists interested in electrical effects in atmospheres and planetary systems. Graduate students and researchers who are new to t...

  4. BETA SPECTRA. I. Negatrons spectra

    International Nuclear Information System (INIS)

    Grau Malonda, A.; Garcia-Torano, E.

    1978-01-01

    Using the Fermi theory of beta decay, the beta spectra for 62 negatrons emitters have been computed introducing a correction factor for unique forbidden transitions. These spectra are plotted vs. energy, once normal i sed, and tabulated with the related Fermi functions. The average and median energies are calculated. (Author)

  5. Pattern recognition in spectra

    Science.gov (United States)

    Gebran, M.; Paletou, F.

    2017-06-01

    We present a new automated procedure that simultaneously derives the effective temperature Teff, surface gravity log g, metallicity [Fe/H], and equatorial projected rotational velocity ve sin i for stars. The procedure is inspired by the well-known PCA-based inversion of spectropolarimetric full-Stokes solar data, which was used both for Zeeman and Hanle effects. The efficiency and accuracy of this procedure have been proven for FGK, A, and late type dwarf stars of K and M spectral types. Learning databases are generated from the Elodie stellar spectra library using observed spectra for which fundamental parameters were already evaluated or with synthetic data. The synthetic spectra are calculated using ATLAS9 model atmospheres. This technique helped us to detect many peculiar stars such as Am, Ap, HgMn, SiEuCr and binaries. This fast and efficient technique could be used every time a pattern recognition is needed. One important application is the understanding of the physical properties of planetary surfaces by comparing aboard instrument data to synthetic ones.

  6. Pattern recognition in spectra

    International Nuclear Information System (INIS)

    Gebran, M; Paletou, F

    2017-01-01

    We present a new automated procedure that simultaneously derives the effective temperature T eff , surface gravity log g , metallicity [ Fe/H ], and equatorial projected rotational velocity v e sin i for stars. The procedure is inspired by the well-known PCA-based inversion of spectropolarimetric full-Stokes solar data, which was used both for Zeeman and Hanle effects. The efficiency and accuracy of this procedure have been proven for FGK, A, and late type dwarf stars of K and M spectral types. Learning databases are generated from the Elodie stellar spectra library using observed spectra for which fundamental parameters were already evaluated or with synthetic data. The synthetic spectra are calculated using ATLAS9 model atmospheres. This technique helped us to detect many peculiar stars such as Am, Ap, HgMn, SiEuCr and binaries. This fast and efficient technique could be used every time a pattern recognition is needed. One important application is the understanding of the physical properties of planetary surfaces by comparing aboard instrument data to synthetic ones. (paper)

  7. SOLAR-WIND ION-DRIVEN X-RAY EMISSION FROM COMETARY AND PLANETARY ATMOSPHERES: MEASUREMENTS AND THEORETICAL PREDICTIONS OF CHARGE-EXCHANGE CROSS-SECTIONS AND EMISSION SPECTRA FOR O{sup 6+} + H{sub 2}O, CO, CO{sub 2}, CH{sub 4}, N{sub 2}, NO, N{sub 2}O, AND Ar

    Energy Technology Data Exchange (ETDEWEB)

    Machacek, J. R. [Atomic and Molecular Physics Laboratory, Research School of Physics and Engineering, The Australian National University, Canberra 2601 (Australia); Mahapatra, D. P. [Department of Physics, Utkal University, Bhubaneswar 751004 (India); Schultz, D. R. [Department of Physics, Univ. of North Texas, Denton, TX 76203 (United States); Ralchenko, Yu. [Atomic Spectroscopy Group, National Institute of Standards and Technology, Gaithersburg, MD 20899-8422 (United States); Moradmand, A.; El Ghazaly, M. O. A.; Chutjian, A. [Astrophysics and Space Sciences Section, Jet Propulsion Laboratory/Caltech, Pasadena, CA 91109 (United States)

    2015-08-10

    Relevant to modeling and understanding X-ray emission from cometary and planetary atmospheres, total cross-sections for 1.17 and 2.33 keV/u O{sup 6+} colliding with H{sub 2}O, CO, CO{sub 2}, CH{sub 4}, N{sub 2}, NO, N{sub 2}O, and Ar have been measured for the processes of single, double, and triple charge exchanges. Using these measurements as benchmarks, synthetic emission spectra spanning the X-ray, UV, and visible range have been calculated based on theoretical treatment of the transfer of between one and six electrons from the target neutrals to the projectile ion, followed by radiative and non-radiative decay of the highly excited states produced in these collisions. The results help add to the base of knowledge required to simulate ion-neutral processes in astrophysical environments; refine the present understanding of these fundamental atomic processes; and guide future observations, laboratory measurements, and theoretical predictions.

  8. Gazetteer of Planetary Nomenclature

    Data.gov (United States)

    National Aeronautics and Space Administration — Planetary nomenclature, like terrestrial nomenclature, is used to uniquely identify a feature on the surface of a planet or satellite so that the feature can be...

  9. PSUP: A Planetary SUrface Portal

    Science.gov (United States)

    Poulet, F.; Quantin-Nataf, C.; Ballans, H.; Dassas, K.; Audouard, J.; Carter, J.; Gondet, B.; Lozac'h, L.; Malapert, J.-C.; Marmo, C.; Riu, L.; Séjourné, A.

    2018-01-01

    . It also allows overlapping of these data products on a virtual Martian globe, which can be difficult to use collectively. The architecture of PSUP data management layer and visualization is based on SITools2 (Malapert and Marseille, 2012) and MIZAR (Module for Interactive visualiZation from Astronomical Repositories) respectively, two CNES generic tools developed by a joint effort between the French space agency (CNES) and French scientific laboratories. Future developments include the addition of high level products of Mars (regional geological maps, new global compositional maps…) and tools (spectra extraction from hyperspectral cubes). Ultimately, PSUP will be adapted to other planetary surfaces and space missions in which the French research institutes are involved.

  10. Double photoionisation spectra of molecules

    CERN Document Server

    Eland, John

    2017-01-01

    This book contains spectra of the doubly charged positive ions (dications) of some 75 molecules, including the major constituents of terrestrial and planetary atmospheres and prototypes of major chemical groups. It is intended to be a new resource for research in all areas of molecular spectroscopy involving high energy environments, both terrestrial and extra-terrestrial. All the spectra have been produced by photoionisation using laboratory lamps or synchrotron radiation and have been measured using the magnetic bottle time-of-flight technique by coincidence detection of correlated electron pairs. Full references to published work on the same species are given, though for several molecules these are the first published spectra. Double ionisation energies are listed and discussed in relation to the molecular electronic structure of the molecules. A full introduction to the field of molecular double ionisation is included and the mechanisms by which double photoionisation can occur are examined in detail. A p...

  11. Polarization Spectra of Extrasolar Giant Planets

    NARCIS (Netherlands)

    Stam, D.M.

    2004-01-01

    We present simulated spectra of the flux and degree of polarization of starlight that is reflected by extrasolar giant planets (EGPs). In particular the polarization depends strongly on the structure of the planetary atmosphere, and appears to be a valuable tool for the characterization of EGPs.

  12. Non-planetary Science from Planetary Missions

    Science.gov (United States)

    Elvis, M.; Rabe, K.; Daniels, K.

    2015-12-01

    Planetary science is naturally focussed on the issues of the origin and history of solar systems, especially our own. The implications of an early turbulent history of our solar system reach into many areas including the origin of Earth's oceans, of ores in the Earth's crust and possibly the seeding of life. There are however other areas of science that stand to be developed greatly by planetary missions, primarily to small solar system bodies. The physics of granular materials has been well-studied in Earth's gravity, but lacks a general theory. Because of the compacting effects of gravity, some experiments desired for testing these theories remain impossible on Earth. Studying the behavior of a micro-gravity rubble pile -- such as many asteroids are believed to be -- could provide a new route towards exploring general principles of granular physics. These same studies would also prove valuable for planning missions to sample these same bodies, as techniques for anchoring and deep sampling are difficult to plan in the absence of such knowledge. In materials physics, first-principles total-energy calculations for compounds of a given stoichiometry have identified metastable, or even stable, structures distinct from known structures obtained by synthesis under laboratory conditions. The conditions in the proto-planetary nebula, in the slowly cooling cores of planetesimals, and in the high speed collisions of planetesimals and their derivatives, are all conditions that cannot be achieved in the laboratory. Large samples from comets and asteroids offer the chance to find crystals with these as-yet unobserved structures as well as more exotic materials. Some of these could have unusual properties important for materials science. Meteorites give us a glimpse of these exotic materials, several dozen of which are known that are unique to meteorites. But samples retrieved directly from small bodies in space will not have been affected by atmospheric entry, warmth or

  13. The ISO-SWS spectrum of planetary nebula NGC 7027

    NARCIS (Netherlands)

    Salas, JB; Pottasch, [No Value; Beintema, DA; Wesselius, PR

    We present the infrared spectrum of the planetary nebula NGC7027 observed with the Short Wavelength Spectrometer (SWS), on board the Infrared Space Observatory (ISO). These data allow us to derive the electron density and, together with the IUE and optical spectra, the electron temperature for

  14. Airships for Planetary Exploration

    Science.gov (United States)

    Colozza, Anthony

    2004-01-01

    The feasibility of utilizing an airship for planetary atmospheric exploration was assessed. The environmental conditions of the planets and moons within our solar system were evaluated to determine their applicability for airship flight. A station-keeping mission of 50 days in length was used as the baseline mission. Airship sizing was performed utilizing both solar power and isotope power to meet the baseline mission goal at the selected planetary location. The results show that an isotope-powered airship is feasible within the lower atmosphere of Venus and Saturn s moon Titan.

  15. Ultraviolet spectroscopy of planetary nebulae in the Magellanic Clouds

    International Nuclear Information System (INIS)

    Maran, S.P.; Aller, L.H.; Gull, T.R.; Stecher, T.P.

    1982-01-01

    Ultraviolet spectra of three high excitation planetary nebulae in the Magellanic Clouds (LMC P40, SMC N2, SMC N5) were obtained with the International Ultraviolet Explorer. The results are analyzed together with new visual wavelength spectrophotometry of LMC P40 and published data on SMC N2 and SMC N5 to investigate chemical composition and in particular to make the first reliable estimates of the carbon abundance in extragalactic planetary nebulae. Although carbon is at most only slightly less abundant in the LMC and SMC planetary nebulae than in galactic planetaries, it is almost 40 times more abundant in the SMC planetaries than in the SMC interstellar medium, and is about 6 times more abundant in the LMC planetary than in the LMC interstellar medium. According to our limited sample, the net result of carbon synthesis and convective dredgeup in the progenitors of planetary nebulae, as reflected in the nebular carbon abundance, is roughly the same in the Galaxy, the LMC, and the SMC

  16. Looking for planetary moons in the spectra of distant Jupiters.

    Science.gov (United States)

    Williams, D M; Knacke, R F

    2004-01-01

    More than 100 nearby stars are known to have at least one Jupiter-sized planet. Whether any of these giant gaseous planets has moons is unknown, but here we suggest a possible way of detecting Earth-sized moons with future technology. The planned Terrestrial Planet Finder observatory, for example, will be able to detect objects comparable in size to Earth. Such Earth-sized objects might orbit their stars either as isolated planets or as moons to giant planets. Moons of Jovian-sized planets near the habitable zones of main-sequence stars should be noticeably brighter than their host planets in the near-infrared (1-4 microm) if their atmospheres contain methane, water, and water vapor, because of efficient absorption of starlight by these atmospheric components. By taking advantage of this spectral contrast, future space observatories will be able to discern which extrasolar giant planets have Earth-like moons capable of supporting life.

  17. New and misclassified planetary nebulae

    International Nuclear Information System (INIS)

    Kohoutek, L.

    1978-01-01

    Since the 'Catalogue of Galactic Planetary Nebulae' 226 new objects have been classified as planetary nebulae. They are summarized in the form of designations, names, coordinates and the references to the discovery. Further 9 new objects have been added and called 'proto-planetary nebulae', but their status is still uncertain. Only 34 objects have been included in the present list of misclassified planetary nebulae although the number of doubtful cases is much larger. (Auth.)

  18. Dust in planetary nebulae

    International Nuclear Information System (INIS)

    Mathis, J.S.

    1978-01-01

    The author's review concentrates on theoretical aspects of dust in planetary nebulae (PN). He considers the questions: how much dust is there is PN; what is its composition; what effects does it have on the ionization structure, on the dynamics of the nebula. (Auth.)

  19. On Aryabhata's Planetary Constants

    OpenAIRE

    Kak, Subhash

    2001-01-01

    This paper examines the theory of a Babylonian origin of Aryabhata's planetary constants. It shows that Aryabhata's basic constant is closer to the Indian counterpart than to the Babylonian one. Sketching connections between Aryabhata's framework and earlier Indic astronomical ideas on yugas and cyclic calendar systems, it is argued that Aryabhata's system is an outgrowth of an earlier Indic tradition.

  20. The planetary scientist's companion

    CERN Document Server

    Lodders, Katharina

    1998-01-01

    A comprehensive and practical book of facts and data about the Sun, planets, asteroids, comets, meteorites, the Kuiper belt and Centaur objects in our solar system. Also covered are properties of nearby stars, the interstellar medium, and extra-solar planetary systems.

  1. Spatiokinematical models of five planetary nebulae

    International Nuclear Information System (INIS)

    Sabbadin, F.

    1984-01-01

    The [OOOI] and Hα expansion velocity fields in the planetary nebulae NGC6058 and 6804 and the [OIII], Hα and [NII] expansion velocity fields in NGC6309, 6751 and 6818, were obtained from high dispersion spectra. Spatiokinematical models of the nebulae were derived assuming an expansion velocity of the gas proportional to the distance from the central star and using the expansion velocity-radius correlation previously given. The observational parameters of the nebulae (radius, mass and expansion velocity) and of the exciting stars (temperature, radius and luminosity) closely fit the suggested evolutionary model for this class of objects. (author)

  2. Emission lines of Mg2 and Ca2 in planetary nebulae

    International Nuclear Information System (INIS)

    Gurzadyan, G.A.

    1979-01-01

    Conditions of exciting resonance lines in the emission of ionized magnesium (lambda lambda 2796+2803 Mg2) and calcium (lambda lambda 3934+3968 Ca2) in planetary nebulae have been analyzed. It is shown that the allowed lines are excited with the same mechanism, as the forbidden lines, i.e. inelastic electron collisions, but not with common fluorescence. The emission line lambda 2800 Mg2 of enough force can be observed only in the spectra of planetary nebulae with mean excitation (IC 2149) as well as in the spectra of diffuse nebulae. The line must not be observed in high-excited planetary nebulae (NGC 7026, 7662). The absence of emission lines H and K Ca2 in planetary nebulae spectra results from the fact, that their expected intensity is by 3-4 orders less than the intensity of the line lambda 2800 Mg2 or Hsub(β) hydrogen

  3. Artificial Intelligence in planetary spectroscopy

    Science.gov (United States)

    Waldmann, Ingo

    2017-10-01

    The field of exoplanetary spectroscopy is as fast moving as it is new. Analysing currently available observations of exoplanetary atmospheres often invoke large and correlated parameter spaces that can be difficult to map or constrain. This is true for both: the data analysis of observations as well as the theoretical modelling of their atmospheres.Issues of low signal-to-noise data and large, non-linear parameter spaces are nothing new and commonly found in many fields of engineering and the physical sciences. Recent years have seen vast improvements in statistical data analysis and machine learning that have revolutionised fields as diverse as telecommunication, pattern recognition, medical physics and cosmology.In many aspects, data mining and non-linearity challenges encountered in other data intensive fields are directly transferable to the field of extrasolar planets. In this conference, I will discuss how deep neural networks can be designed to facilitate solving said issues both in exoplanet atmospheres as well as for atmospheres in our own solar system. I will present a deep belief network, RobERt (Robotic Exoplanet Recognition), able to learn to recognise exoplanetary spectra and provide artificial intelligences to state-of-the-art atmospheric retrieval algorithms. Furthermore, I will present a new deep convolutional network that is able to map planetary surface compositions using hyper-spectral imaging and demonstrate its uses on Cassini-VIMS data of Saturn.

  4. Planetary seismology and interiors

    Science.gov (United States)

    Toksoz, M. N.

    1979-01-01

    This report briefly summarizes knowledge gained in the area of planetary seismology in the period 1969-1979. Attention is given to the seismic instruments, the seismic environment (noise, characteristics of seismic wave propagation, etc.), and the seismicity of the moon and Mars as determined by the Apollo missions and Viking Lander experiments, respectively. The models of internal structures of the terrestrial planets are discussed, with the earth used for reference.

  5. Galactic planetary science.

    Science.gov (United States)

    Tinetti, Giovanna

    2014-04-28

    Planetary science beyond the boundaries of our Solar System is today in its infancy. Until a couple of decades ago, the detailed investigation of the planetary properties was restricted to objects orbiting inside the Kuiper Belt. Today, we cannot ignore that the number of known planets has increased by two orders of magnitude nor that these planets resemble anything but the objects present in our own Solar System. Whether this fact is the result of a selection bias induced by the kind of techniques used to discover new planets--mainly radial velocity and transit--or simply the proof that the Solar System is a rarity in the Milky Way, we do not know yet. What is clear, though, is that the Solar System has failed to be the paradigm not only in our Galaxy but even 'just' in the solar neighbourhood. This finding, although unsettling, forces us to reconsider our knowledge of planets under a different light and perhaps question a few of the theoretical pillars on which we base our current 'understanding'. The next decade will be critical to advance in what we should perhaps call Galactic planetary science. In this paper, I review highlights and pitfalls of our current knowledge of this topic and elaborate on how this knowledge might arguably evolve in the next decade. More critically, I identify what should be the mandatory scientific and technical steps to be taken in this fascinating journey of remote exploration of planets in our Galaxy.

  6. Europlanet Research Infrastructure: Planetary Simulation Facilities

    Science.gov (United States)

    Davies, G. R.; Mason, N. J.; Green, S.; Gómez, F.; Prieto, O.; Helbert, J.; Colangeli, L.; Srama, R.; Grande, M.; Merrison, J.

    2008-09-01

    pressures and temperatures and through provision of external UV light and or electrical discharge can be used to form the well known Titan Aerosol species, which can subsequently be analysed using one of several analytical techniques (UV-Vis, FTIR and mass spectrometry). Simulated surfaces can be produced (icy surfaces down to 15K) and subjected to a variety of light and particles (electron and ion) sources. Chemical and physical changes in the surface may be explored using remote spectroscopy. Planetary Simulation chamber for low density atmospheres INTA-CAB The planetary simulation chamber-ultra-high vacuum equipment (PSC-UHV) has been designed to study planetary surfaces and low dense atmospheres, space environments or any other hypothetic environment at UHV. Total pressure ranges from 7 mbar (Martian conditions) to 5x10-9 mbar. A residual gas analyzer regulates gas compositions to ppm precision. Temperature ranges from 4K to 325K and most operations are computer controlled. Radiation levels are simulated using a deuterium UV lamp, and ionization sources. 5 KV electron and noble-gas discharge UV allows measurement of IR and UV spectra and chemical compositions are determined by mass spectroscopy. Planetary Simulation chamber for high density planetary atmospheres at INTA-CAB The facility allows experimental study of planetary environments under high pressure, and was designed to include underground, seafloor and dense atmosphere environments. Analytical capabilities include Raman spectra, physicochemical properties of materials, e.a. thermal conductivity. P-T can be controlled as independent variables to allow monitoring of the tolerance of microorganisms and the stability of materials and their phase changes. Planetary Simulation chamber for icy surfaces at INTA-CAB This chamber is being developed to the growth of ice samples to simulate the chemical and physical properties of ices found on both planetary bodies and their moons. The goal is to allow measurement of the

  7. Abundance in the planetary nebulae NGC 6537 and He2-111

    NARCIS (Netherlands)

    Pottasch, [No Value; Beintema, DA; Feibelman, WA

    2000-01-01

    The ISO and IUE spectra of the bipolar planetary nebulae NGC 6537 and He2-111 are presented. These spectra are combined with the spectrum in the visual wavelength region from the nebulae to obtain a complete spectrum that is corrected for extinction. The chemical abundance of the nebulae is then

  8. Planetary tides during the Maunder sunspot minimum

    International Nuclear Information System (INIS)

    Smythe, C.M.; Eddy, J.A.

    1977-01-01

    Sun-centered planetary conjunctions and tidal potentials are here constructed for the AD1645 to 1715 period of sunspot absence, referred to as the 'Maunder Minimum'. These are found to be effectively indistinguishable from patterns of conjunctions and power spectra of tidal potential in the present era of a well established 11 year sunspot cycle. This places a new and difficult restraint on any tidal theory of sunspot formation. Problems arise in any direct gravitational theory due to the apparently insufficient forces and tidal heights involved. Proponents of the tidal hypothesis usually revert to trigger mechanisms, which are difficult to criticise or test by observation. Any tidal theory rests on the evidence of continued sunspot periodicity and the substantiation of a prolonged period of solar anomaly in the historical past. The 'Maunder Minimum' was the most drastic change in the behaviour of solar activity in the last 300 years; sunspots virtually disappeared for a 70 year period and the 11 year cycle was probably absent. During that time, however, the nine planets were all in their orbits, and planetary conjunctions and tidal potentials were indistinguishable from those of the present era, in which the 11 year cycle is well established. This provides good evidence against the tidal theory. The pattern of planetary tidal forces during the Maunder Minimum was reconstructed to investigate the possibility that the multiple planet forces somehow fortuitously cancelled at the time, that is that the positions of the slower moving planets in the 17th and early 18th centuries were such that conjunctions and tidal potentials were at the time reduced in number and force. There was no striking dissimilarity between the time of the Maunder Minimum and any period investigated. The failure of planetary conjunction patterns to reflect the drastic drop in sunspots during the Maunder Minimum casts doubt on the tidal theory of solar activity, but a more quantitative test

  9. Robotic Planetary Drill Tests

    Science.gov (United States)

    Glass, Brian J.; Thompson, S.; Paulsen, G.

    2010-01-01

    Several proposed or planned planetary science missions to Mars and other Solar System bodies over the next decade require subsurface access by drilling. This paper discusses the problems of remote robotic drilling, an automation and control architecture based loosely on observed human behaviors in drilling on Earth, and an overview of robotic drilling field test results using this architecture since 2005. Both rotary-drag and rotary-percussive drills are targeted. A hybrid diagnostic approach incorporates heuristics, model-based reasoning and vibration monitoring with neural nets. Ongoing work leads to flight-ready drilling software.

  10. Estimating the Binary Fraction of Central Stars of Planetary Nebulae

    Science.gov (United States)

    Douchin, Dimitri

    2015-01-01

    Planetary nebulae are the end-products of intermediate-mass stars evolution, following a phase of expansion of their atmospheres at the end of their lives. Observationally, it has been estimated that 80% of them have non-spherical shapes. Such a high fraction is puzzling and has occupied the planetary nebula community for more than 30 years. One scenario that would allow to justify the observed shapes is that a comparable fraction of the progenitors of central stars of planetary nebula (CSPN) are not single, but possess a companion. The shape of the nebulae would then be the result of an interaction with this companion. The high fraction of non-spherical planetary nebulae would thus imply a high fraction of binary central stars of planetary nebulae, making binarity a preferred channel for planetary nebula formation. After presenting the current state of knowledge regarding planetary nebula formation and shaping and reviewing the diverse efforts to find binaries in planetary nebulae, I present my work to detect a near-infrared excess that would be the signature of the presence of cool companions. The first part of the project consists in the analysis of data and photometry acquired and conducted by myself. The second part details an attempt to make use of archived datasets: the Sloan Digital Sky Survey Data Release 7 optical survey and the extended database assembled by Frew (2008). I also present results from a radial velocity analysis of VLT/UVES spectra for 14 objects aiming to the detection of spectroscopic companions. Finally I give details of the analysis of optical photometry data from our observations associated to the detection of companions around central stars of planetary nebulae using the photometric variability technique. The main result of this thesis is from the near-infrared excess studies which I combine with previously published data. I conclude that if the detected red and NIR flux excess is indicative of a stellar companion then the binary

  11. Planetary Sciences and Exploration Programme

    Indian Academy of Sciences (India)

    The Indian Space Research Organisation (ISRO) has taken a number of initiatives to plan for a National. Research Programme in the area of planetary science and exploration. This announcement solicits proposals in the field of planetary science. Universities, research and educational institutions may submit proposals ...

  12. Abundances in Eight M31 Planetary Nebulae

    Science.gov (United States)

    Hensley, Kerry G.; Kwitter, Karen B.; Corradi, Romano; Galera-Rosillo, R.; Balick, Bruce; Henry, Richard B. C.

    2014-06-01

    As part of a continuing project using planetary nebulae (PNe) to study the chemical evolution and formation history of M31 (see accompanying poster by Balick et al.), we obtained spectra of eight PNe in the fall of 2013 with the OSIRIS spectrograph on the GTC. All of these PNe are located outside M31’s inner disk and bulge. Spectral coverage extended from 3700-7800Å with a resolution of ~6 Å. Especially important in abundance determinations is the detection of the weak, temperature-sensitive auroral line of [O III], at 4363Å, which is often contaminated by Hg I 4358Å from streetlights; the remoteness of the GTC eliminated this difficulty. We reduced and measured the spectra using IRAF, and derived nebular diagnostics and abundances with ELSA, our in-house five-level-atom program. Here we report the chemical abundances determined from these spectra. The bottom line is that the oxygen abundances in these PNe are all within a factor of 2-3 of the solar value, (as are all the other M31 PNe our team has previously measured) despite the significant range of galactocentric distance. Future work will use these abundances to constrain models of the central star to estimate progenitor masses and ages. In particular we will use the results to investigate the hypothesis that these PNe might represent a population related to the encounter between M31 and M33 ~3 Gy ago. We gratefully acknowledge support from Williams College.

  13. Technology under Planetary Protection Research (PPR)

    Data.gov (United States)

    National Aeronautics and Space Administration — Planetary protection involves preventing biological contamination on both outbound and sample return missions to other planetary bodies. Numerous areas of research...

  14. Planetary heat flow measurements.

    Science.gov (United States)

    Hagermann, Axel

    2005-12-15

    The year 2005 marks the 35th anniversary of the Apollo 13 mission, probably the most successful failure in the history of manned spaceflight. Naturally, Apollo 13's scientific payload is far less known than the spectacular accident and subsequent rescue of its crew. Among other instruments, it carried the first instrument designed to measure the flux of heat on a planetary body other than Earth. The year 2005 also should have marked the launch of the Japanese LUNAR-A mission, and ESA's Rosetta mission is slowly approaching comet Churyumov-Gerasimenko. Both missions carry penetrators to study the heat flow from their target bodies. What is so interesting about planetary heat flow? What can we learn from it and how do we measure it?Not only the Sun, but all planets in the Solar System are essentially heat engines. Various heat sources or heat reservoirs drive intrinsic and surface processes, causing 'dead balls of rock, ice or gas' to evolve dynamically over time, driving convection that powers tectonic processes and spawns magnetic fields. The heat flow constrains models of the thermal evolution of a planet and also its composition because it provides an upper limit for the bulk abundance of radioactive elements. On Earth, the global variation of heat flow also reflects the tectonic activity: heat flow increases towards the young ocean ridges, whereas it is rather low on the old continental shields. It is not surprising that surface heat flow measurements, or even estimates, where performed, contributed greatly to our understanding of what happens inside the planets. In this article, I will review the results and the methods used in past heat flow measurements and speculate on the targets and design of future experiments.

  15. Solar planetary systems stardust to terrestrial and extraterrestrial planetary sciences

    CERN Document Server

    Bhattacharya, Asit B

    2017-01-01

    The authors have put forth great efforts in gathering present day knowledge about different objects within our solar system and universe. This book features the most current information on the subject with information acquired from noted scientists in this area. The main objective is to convey the importance of the subject and provide detailed information on the physical makeup of our planetary system and technologies used for research. Information on educational projects has also been included in the Radio Astronomy chapters.This information is a real plus for students and educators considering a career in Planetary Science or for increasing their knowledge about our planetary system

  16. Flux and polarisation spectra of water clouds on exoplanets

    NARCIS (Netherlands)

    Karalidi, T.; Stam, D.M.; Hovenier, J.W.

    2011-01-01

    Context. A crucial factor for a planet’s habitability is its climate. Clouds play an important role in planetary climates. Detecting and characterising clouds on an exoplanet is therefore crucial when addressing this planet’s habitability. Aims. We present calculated flux and polarisation spectra of

  17. Planetary Landscape Geography

    Science.gov (United States)

    Hargitai, H.

    INTRODUCTION Landscape is one of the most often used category in physical ge- ography. The term "landshap" was introduced by Dutch painters in the 15-16th cen- tury. [1] The elements that build up a landscape (or environment) on Earth consists of natural (biogenic and abiogenic - lithologic, atmospheric, hydrologic) and artificial (antropogenic) factors. Landscape is a complex system of these different elements. The same lithology makes different landscapes under different climatic conditions. If the same conditions are present, the same landscape type will appear. Landscapes build up a hierarchic system and cover the whole surface. On Earth, landscapes can be classified and qualified according to their characteristics: relief forms (morphology), and its potential economic value. Aesthetic and subjective parameters can also be considered. Using the data from landers and data from orbiters we can now classify planetary landscapes (these can be used as geologic mapping units as well). By looking at a unknown landscape, we can determine the processes that created it and its development history. This was the case in the Pathfinder/Sojourner panoramas. [2]. DISCUSSION Planetary landscape evolution. We can draw a raw landscape develop- ment history by adding the different landscape building elements to each other. This has a strong connection with the planet's thermal evolution (age of the planet or the present surface materials) and with orbital parameters (distance from the central star, orbit excentricity etc). This way we can build a complex system in which we use differ- ent evolutional stages of lithologic, atmospheric, hydrologic and biogenic conditions which determine the given - Solar System or exoplanetary - landscape. Landscape elements. "Simple" landscapes can be found on asteroids: no linear horizon is present (not differentiated body, only impact structures), no atmosphere (therefore no atmospheric scattering - black sky as part of the landscape) and no

  18. Planetary Protection Constraints For Planetary Exploration and Exobiology

    Science.gov (United States)

    Debus, A.; Bonneville, R.; Viso, M.

    According to the article IX of the OUTER SPACE TREATY (London / Washington January 27., 1967) and in the frame of extraterrestrial missions, it is required to preserve planets and Earth from contamination. For ethical, safety and scientific reasons, the space agencies have to comply with the Outer Space Treaty and to take into account the related planetary protection Cospar recommendations. Planetary protection takes also into account the protection of exobiological science, because the results of life detection experimentations could have impacts on planetary protection regulations. The validation of their results depends strongly of how the samples have been collected, stored and analyzed, and particularly of their biological and organic cleanliness. Any risk of contamination by organic materials, chemical coumpounds and by terrestrial microorganisms must be avoided. A large number of missions is presently scheduled, particularly on Mars, in order to search for life or traces of past life. In the frame of such missions, CNES is building a planetary protection organization in order handle and to take in charge all tasks linked to science and engineering concerned by planetary protection. Taking into account CNES past experience in planetary protection related to the Mars 96 mission, its planned participation in exobiological missions with NASA as well as its works and involvement in Cospar activities, this paper will present the main requirements in order to avoid celestial bodies biological contamination, focussing on Mars and including Earth, and to protect exobiological science.

  19. Kinematics of galactic planetary nebulae

    International Nuclear Information System (INIS)

    Kiosa, M.I.; Khromov, G.S.

    1979-01-01

    The classical method of determining the components of the solar motion relative to the centroid of the system of planetary nebulae with known radial velocities is investigated. It is shown that this method is insensitive to random errors in the radial velocities and that low accuracy in determining the coordinates of the solar apex and motion results from the insufficient number of planetaries with measured radial velocities. The planetary nebulae are found not to satisfy well the law of differential galactic rotation with circular orbits. This is attributed to the elongation of their galactic orbits. A method for obtaining the statistical parallax of planetary nebulae is considered, and the parallax calculated from the tau components of their proper motion is shown to be the most reliable

  20. In Situ Planetary Geochronology Technology

    Data.gov (United States)

    National Aeronautics and Space Administration — This project's purpose was to determine whether a Pulsed Neutron Generator (PNG) could be used in an instrument that could perform in situ age dating of planetary...

  1. Can planetary nebulae rotate

    International Nuclear Information System (INIS)

    Grinin, V.P.

    1982-01-01

    It is shown that the inclination of spectral lines observed in a number of planetary nebulae when the spectrograph slit is placed along the major axis, which is presently ascribed to nonuniform expansion of the shells, actually may be due to rotation of the nebulae about their minor axes, as Campbell and Moore have suggested in their reports. It is assumed that the rotation of the central star (or, if the core is a binary system, circular motions of gas along quasi-Keplerian orbits) serves as the source of the original rotation of a protoplanetary nebula. The mechanism providing for strengthening of the original rotation in the process of expansion of the shell is the tangential pressure of L/sub α/ radiation due to the anisotropic properties of the medium and radiation field. The dynamic effect produced by them is evidently greatest in the epoch when the optical depth of the nebula in the L/sub c/ continuum becomes on the order of unity in the course of its expansion

  2. Planetary Geologic Mapping Handbook - 2009

    Science.gov (United States)

    Tanaka, K. L.; Skinner, J. A.; Hare, T. M.

    2009-01-01

    Geologic maps present, in an historical context, fundamental syntheses of interpretations of the materials, landforms, structures, and processes that characterize planetary surfaces and shallow subsurfaces (e.g., Varnes, 1974). Such maps also provide a contextual framework for summarizing and evaluating thematic research for a given region or body. In planetary exploration, for example, geologic maps are used for specialized investigations such as targeting regions of interest for data collection and for characterizing sites for landed missions. Whereas most modern terrestrial geologic maps are constructed from regional views provided by remote sensing data and supplemented in detail by field-based observations and measurements, planetary maps have been largely based on analyses of orbital photography. For planetary bodies in particular, geologic maps commonly represent a snapshot of a surface, because they are based on available information at a time when new data are still being acquired. Thus the field of planetary geologic mapping has been evolving rapidly to embrace the use of new data and modern technology and to accommodate the growing needs of planetary exploration. Planetary geologic maps have been published by the U.S. Geological Survey (USGS) since 1962 (Hackman, 1962). Over this time, numerous maps of several planetary bodies have been prepared at a variety of scales and projections using the best available image and topographic bases. Early geologic map bases commonly consisted of hand-mosaicked photographs or airbrushed shaded-relief views and geologic linework was manually drafted using mylar bases and ink drafting pens. Map publishing required a tedious process of scribing, color peel-coat preparation, typesetting, and photo-laboratory work. Beginning in the 1990s, inexpensive computing, display capability and user-friendly illustration software allowed maps to be drawn using digital tools rather than pen and ink, and mylar bases became obsolete

  3. NASA Planetary Visualization Tool

    Science.gov (United States)

    Hogan, P.; Kim, R.

    2004-12-01

    NASA World Wind allows one to zoom from satellite altitude into any place on Earth, leveraging the combination of high resolution LandSat imagery and SRTM elevation data to experience Earth in visually rich 3D, just as if they were really there. NASA World Wind combines LandSat 7 imagery with Shuttle Radar Topography Mission (SRTM) elevation data, for a dramatic view of the Earth at eye level. Users can literally fly across the world's terrain from any location in any direction. Particular focus was put into the ease of usability so people of all ages can enjoy World Wind. All one needs to control World Wind is a two button mouse. Additional guides and features can be accessed though a simplified menu. Navigation is automated with single clicks of a mouse as well as the ability to type in any location and automatically zoom to it. NASA World Wind was designed to run on recent PC hardware with the same technology used by today's 3D video games. NASA World Wind delivers the NASA Blue Marble, spectacular true-color imagery of the entire Earth at 1-kilometer-per-pixel. Using NASA World Wind, you can continue to zoom past Blue Marble resolution to seamlessly experience the extremely detailed mosaic of LandSat 7 data at an impressive 15-meters-per-pixel resolution. NASA World Wind also delivers other color bands such as the infrared spectrum. The NASA Scientific Visualization Studio at Goddard Space Flight Center (GSFC) has produced a set of visually intense animations that demonstrate a variety of subjects such as hurricane dynamics and seasonal changes across the globe. NASA World Wind takes these animations and plays them directly on the world. The NASA Moderate Resolution Imaging Spectroradiometer (MODIS) produces a set of time relevant planetary imagery that's updated every day. MODIS catalogs fires, floods, dust, smoke, storms and volcanic activity. NASA World Wind produces an easily customized view of this information and marks them directly on the globe. When one

  4. The OpenPlanetary initiative

    Science.gov (United States)

    Manaud, Nicolas; Rossi, Angelo Pio; Hare, Trent; Aye, Michael; Galluzzi, Valentina; van Gasselt, Stephan; Martinez, Santa; McAuliffe, Jonathan; Million, Chase; Nass, Andrea; Zinzi, Angelo

    2016-10-01

    "Open" has become attached to several concepts: science, data, and software are some of the most obvious. It is already common practice within the planetary science community to share spacecraft missions data freely and openly [1]. However, this is not historically the case for software tools, source code, and derived data sets, which are often reproduced independently by multiple individuals and groups. Sharing data, tools and overall knowledge would increase scientific return and benefits [e.g. 2], and recent projects and initiatives are helping toward this goal [e.g. 3,4,5,6].OpenPlanetary is a bottom-up initiative to address the need of the planetary science community for sharing ideas and collaborating on common planetary research and data analysis problems, new challenges, and opportunities. It started from an initial participants effort to stay connected and share information related to and beyond the ESA's first Planetary GIS Workshop [7]. It then continued during the 2nd (US) Planetary Data Workshop [8], and aggregated more people.Our objective is to build an online distributed framework enabling open collaborations within the planetary science community. We aim to co-create, curate and publish resource materials and data sets; to organise online events, to support community-based projects development; and to offer a real-time communication channel at and between conferences and workshops.We will present our current framework and resources, developing projects and ideas, and solicit for feedback and participation. OpenPlanetary is intended for research and education professionals: scientists, engineers, designers, teachers and students, as well as the general public that includes enthusiasts and citizen scientists. All are welcome to join and contribute at openplanetary.co[1] International Planetary Data Alliance, planetarydata.org. [2] Nosek et al (2015), dx.doi.org/10.1126/science.aab2374. [3] Erard S. et al. (2016), EGU2016-17527. [4] Proposal for a PDS

  5. Planetary Transmission Diagnostics

    Science.gov (United States)

    Lewicki, David G. (Technical Monitor); Samuel, Paul D.; Conroy, Joseph K.; Pines, Darryll J.

    2004-01-01

    This report presents a methodology for detecting and diagnosing gear faults in the planetary stage of a helicopter transmission. This diagnostic technique is based on the constrained adaptive lifting algorithm. The lifting scheme, developed by Wim Sweldens of Bell Labs, is a time domain, prediction-error realization of the wavelet transform that allows for greater flexibility in the construction of wavelet bases. Classic lifting analyzes a given signal using wavelets derived from a single fundamental basis function. A number of researchers have proposed techniques for adding adaptivity to the lifting scheme, allowing the transform to choose from a set of fundamental bases the basis that best fits the signal. This characteristic is desirable for gear diagnostics as it allows the technique to tailor itself to a specific transmission by selecting a set of wavelets that best represent vibration signals obtained while the gearbox is operating under healthy-state conditions. However, constraints on certain basis characteristics are necessary to enhance the detection of local wave-form changes caused by certain types of gear damage. The proposed methodology analyzes individual tooth-mesh waveforms from a healthy-state gearbox vibration signal that was generated using the vibration separation (synchronous signal-averaging) algorithm. Each waveform is separated into analysis domains using zeros of its slope and curvature. The bases selected in each analysis domain are chosen to minimize the prediction error, and constrained to have the same-sign local slope and curvature as the original signal. The resulting set of bases is used to analyze future-state vibration signals and the lifting prediction error is inspected. The constraints allow the transform to effectively adapt to global amplitude changes, yielding small prediction errors. However, local wave-form changes associated with certain types of gear damage are poorly adapted, causing a significant change in the

  6. Planetary Geophysics and Tectonics

    Science.gov (United States)

    Zuber, Maria

    2005-01-01

    The broad objective of this work is to improve understanding of the internal structures and thermal and stress histories of the solid planets by combining results from analytical and computational modeling, and geophysical data analysis of gravity, topography and tectonic surface structures. During the past year we performed two quite independent studies in the attempt to explain the Mariner 10 magnetic observations of Mercury. In the first we revisited the possibility of crustal remanence by studying the conditions under which one could break symmetry inherent in Runcorn's model of a uniformly magnetized shell to produce a remanent signal with a dipolar form. In the second we applied a thin shell dynamo model to evaluate the range of intensity/structure for which such a planetary configuration can produce a dipole field consistent with Mariner 10 results. In the next full proposal cycle we will: (1) develop numerical and analytical and models of thin shell dynamos to address the possible nature of Mercury s present-day magnetic field and the demise of Mars magnetic field; (2) study the effect of degree-1 mantle convection on a core dynamo as relevant to the early magnetic field of Mars; (3) develop models of how the deep mantles of terrestrial planets are perturbed by large impacts and address the consequences for mantle evolution; (4) study the structure, compensation, state of stress, and viscous relaxation of lunar basins, and address implications for the Moon s state of stress and thermal history by modeling and gravity/topography analysis; and (5) use a three-dimensional viscous relaxation model for a planet with generalized vertical viscosity distribution to study the degree-two components of the Moon's topography and gravity fields to constrain the primordial stress state and spatial heterogeneity of the crust and mantle.

  7. Planetary Image Geometry Library

    Science.gov (United States)

    Deen, Robert C.; Pariser, Oleg

    2010-01-01

    The Planetary Image Geometry (PIG) library is a multi-mission library used for projecting images (EDRs, or Experiment Data Records) and managing their geometry for in-situ missions. A collection of models describes cameras and their articulation, allowing application programs such as mosaickers, terrain generators, and pointing correction tools to be written in a multi-mission manner, without any knowledge of parameters specific to the supported missions. Camera model objects allow transformation of image coordinates to and from view vectors in XYZ space. Pointing models, specific to each mission, describe how to orient the camera models based on telemetry or other information. Surface models describe the surface in general terms. Coordinate system objects manage the various coordinate systems involved in most missions. File objects manage access to metadata (labels, including telemetry information) in the input EDRs and RDRs (Reduced Data Records). Label models manage metadata information in output files. Site objects keep track of different locations where the spacecraft might be at a given time. Radiometry models allow correction of radiometry for an image. Mission objects contain basic mission parameters. Pointing adjustment ("nav") files allow pointing to be corrected. The object-oriented structure (C++) makes it easy to subclass just the pieces of the library that are truly mission-specific. Typically, this involves just the pointing model and coordinate systems, and parts of the file model. Once the library was developed (initially for Mars Polar Lander, MPL), adding new missions ranged from two days to a few months, resulting in significant cost savings as compared to rewriting all the application programs for each mission. Currently supported missions include Mars Pathfinder (MPF), MPL, Mars Exploration Rover (MER), Phoenix, and Mars Science Lab (MSL). Applications based on this library create the majority of operational image RDRs for those missions. A

  8. The fragility of planetary systems

    Science.gov (United States)

    Portegies Zwart, S. F.; Jílková, Lucie

    2015-07-01

    We specify the range to which perturbations penetrate a planetesimal system. Such perturbations can originate from massive planets or from encounters with other stars. The latter can have an origin in the star cluster in which the planetary system was born, or from random encounters once the planetary system has escaped its parental cluster. The probability of a random encounter, either in a star cluster or in the Galactic field depends on the local stellar density, the velocity dispersion and the time spend in that environment. By adopting order of magnitude estimates, we argue that the majority of planetary systems born in open clusters will have a Parking zone, in which planetesimals are affected by encounters in their parental star cluster but remain unperturbed after the star has left the cluster. Objects found in this range of semimajor axis and eccentricity preserve the memory of the encounter that last affected their orbits, and they can therefore be used to reconstruct this encounter. Planetary systems born in a denser environment, such as in a globular cluster are unlikely to have a Parking zone. We further argue that some planetary systems may have a Frozen zone, in which orbits are not affected either by the more inner massive planets or by external influences. Objects discovered in this zone will have preserved information about their formation in their orbital parameters.

  9. Elpasolite Planetary Ice and Composition Spectrometer (EPICS): A Low-Resource Combined Gamma-Ray and Neutron Spectrometer for Planetary Science

    Science.gov (United States)

    Stonehill, L. C.; Coupland, D. D. S.; Dallmann, N. A.; Feldman, W. C.; Mesick, K.; Nowicki, S.; Storms, S.

    2017-12-01

    The Elpasolite Planetary Ice and Composition Spectrometer (EPICS) is an innovative, low-resource gamma-ray and neutron spectrometer for planetary science missions, enabled by new scintillator and photodetector technologies. Neutrons and gamma rays are produced by cosmic ray interactions with planetary bodies and their subsequent interactions with the near-surface materials produce distinctive energy spectra. Measuring these spectra reveals details of the planetary near-surface composition that are not accessible through any other phenomenology. EPICS will be the first planetary science instrument to fully integrate the neutron and gamma-ray spectrometers. This integration is enabled by the elpasolite family of scintillators that offer gamma-ray spectroscopy energy resolutions as good as 3% FWHM at 662 keV, thermal neutron sensitivity, and the ability to distinguish gamma-ray and neutron signals via pulse shape differences. This new detection technology will significantly reduce size, weight, and power (SWaP) while providing similar neutron performance and improved gamma energy resolution compared to previous scintillator instruments, and the ability to monitor the cosmic-ray source term. EPICS will detect scintillation light with silicon photomultipliers rather than traditional photomultiplier tubes, offering dramatic additional SWaP reduction. EPICS is under development with Los Alamos National Laboratory internal research and development funding. Here we report on the EPICS design, provide an update on the current status of the EPICS development, and discuss the expected sensitivity and performance of EPICS in several potential missions to airless bodies.

  10. Fault diagnosis of planetary gearboxes via torsional vibration signal analysis

    Science.gov (United States)

    Feng, Zhipeng; Zuo, Ming J.

    2013-04-01

    Torsional vibration signals are theoretically free from the amplitude modulation effect caused by time variant vibration transfer paths due to the rotation of planet carrier and sun gear, and therefore their spectral structure are simpler than transverse vibration signals. Thus, it is potentially easy and effective to diagnose planetary gearbox faults via torsional vibration signal analysis. We give explicit equations to model torsional vibration signals, considering both distributed gear faults (like manufacturing or assembly errors) and local gear faults (like pitting, crack or breakage of one tooth), and derive the characteristics of both the traditional Fourier spectrum and the proposed demodulated spectra of amplitude envelope and instantaneous frequency. These derivations are not only effective to diagnose single gear fault of planetary gearboxes, but can also be generalized to detect and locate multiple gear faults. We validate experimentally the signal models, as well as the Fourier spectral analysis and demodulation analysis methods.

  11. VARIATIONAL PRINCIPLE FOR PLANETARY INTERIORS

    International Nuclear Information System (INIS)

    Zeng, Li; Jacobsen, Stein B.

    2016-01-01

    In the past few years, the number of confirmed planets has grown above 2000. It is clear that they represent a diversity of structures not seen in our own solar system. In addition to very detailed interior modeling, it is valuable to have a simple analytical framework for describing planetary structures. The variational principle is a fundamental principle in physics, entailing that a physical system follows the trajectory, which minimizes its action. It is alternative to the differential equation formulation of a physical system. Applying the variational principle to the planetary interior can beautifully summarize the set of differential equations into one, which provides us some insight into the problem. From this principle, a universal mass–radius relation, an estimate of the error propagation from the equation of state to the mass–radius relation, and a form of the virial theorem applicable to planetary interiors are derived.

  12. From Planetary Mapping to Map Production: Planetary Cartography as integral discipline in Planetary Sciences

    Science.gov (United States)

    Nass, Andrea; van Gasselt, Stephan; Hargitai, Hendrik; Hare, Trent; Manaud, Nicolas; Karachevtseva, Irina; Kersten, Elke; Roatsch, Thomas; Wählisch, Marita; Kereszturi, Akos

    2016-04-01

    Cartography is one of the most important communication channels between users of spatial information and laymen as well as the open public alike. This applies to all known real-world objects located either here on Earth or on any other object in our Solar System. In planetary sciences, however, the main use of cartography resides in a concept called planetary mapping with all its various attached meanings: it can be (1) systematic spacecraft observation from orbit, i.e. the retrieval of physical information, (2) the interpretation of discrete planetary surface units and their abstraction, or it can be (3) planetary cartography sensu strictu, i.e., the technical and artistic creation of map products. As the concept of planetary mapping covers a wide range of different information and knowledge levels, aims associated with the concept of mapping consequently range from a technical and engineering focus to a scientific distillation process. Among others, scientific centers focusing on planetary cartography are the United State Geological Survey (USGS, Flagstaff), the Moscow State University of Geodesy and Cartography (MIIGAiK, Moscow), Eötvös Loránd University (ELTE, Hungary), and the German Aerospace Center (DLR, Berlin). The International Astronomical Union (IAU), the Commission Planetary Cartography within International Cartographic Association (ICA), the Open Geospatial Consortium (OGC), the WG IV/8 Planetary Mapping and Spatial Databases within International Society for Photogrammetry and Remote Sensing (ISPRS) and a range of other institutions contribute on definition frameworks in planetary cartography. Classical cartography is nowadays often (mis-)understood as a tool mainly rather than a scientific discipline and an art of communication. Consequently, concepts of information systems, mapping tools and cartographic frameworks are used interchangeably, and cartographic workflows and visualization of spatial information in thematic maps have often been

  13. Chemical abundances and dust in planetary nebulae in the Galactic bulge

    NARCIS (Netherlands)

    Gutenkunst, S.; Bernard-Salas, J.; Pottasch, S. R.; Sloan, G. C.; Houck, J. R.

    2008-01-01

    We present mid-infrared Spitzer spectra of 11 planetary nebulae in the Galactic bulge. We derive argon, neon, sulfur, and oxygen abundances for them using mainly infrared line fluxes combined with some optical line fluxes from the literature. Due to the high extinction toward the bulge, the infrared

  14. The Spitzer IRS infrared spectrum and abundances of the planetary nebula IC 2448

    NARCIS (Netherlands)

    Guiles, S.; Bernard-Salas, J.; Pottasch, S. R.; Roellig, T. L.

    2007-01-01

    We present the mid-infrared spectrum of the planetary nebula IC 2448. In order to determine the chemical composition of the nebula, we use the infrared line fluxes from the Spitzer spectrum along with optical line fluxes from the literature and ultraviolet line fluxes from archival IUE spectra. We

  15. The chemical composition of three planetary nebulae in the Magellanic clouds

    International Nuclear Information System (INIS)

    Dufour, R.J.; Killen, R.M.

    1977-01-01

    Emission-line intensities in the planetary nebulae Henize 67 in the Small Magellanic Cloud (SMC) and Henize 97 and 153 in the LMC along with the small SMC H II regions Henize 9, 61, and 81 were measured from photographic image-tube spectra taken with the 1.5 m telescope at Cerro Tololo. The relative abundances of H, He, N, O, Ne, S, and Ar in the nebulae were estimated and compared with the compositions of galactic planetary nebulae and previously studied H II regions in the Clouds. The results show that (1) the N/O ratios in the planetary nebulae are substantially higher than found in the H II regions of each Cloud; (2) He/H approx. = 0.18 in the SMC planetary nebula, but seems normal (approx.0.10) in the two LMC planetaries; and (3) the compositions of the three small SMC H II regions are similar to that of larger SMC H II regions studied previously. It is concluded that the N/H values in the shells of planetary nebulae may not depend on the metal content of the progenitor star as much as recent theoretical models suggest and that the N content of the gas in the Magellanic Clouds arises primarily from sources other than planetary nebulae

  16. SPEX: The spectropolarimeter for planetary EXploration

    NARCIS (Netherlands)

    Snik, F.; Rietjens, J.H.H.; Harten, G. van; Stam, D.M.; Keller, C.U.; Smit, J.M.; Laan, E.C.; Verlaan, A.L.; Horst, R. ter; Navarro, R.; Wielinga, K.; Moon, S.G.; Voors, R.

    2010-01-01

    SPEX (Spectropolarimeter for Planetary EXploration) is an innovative, compact instrument for spectropolarimetry, and in particular for detecting and characterizing aerosols in planetary atmospheres. With its ∼1-liter volume it is capable of full linear spectropolarimetry, without moving parts. The

  17. Red giants as precursors of planetary nebulae

    International Nuclear Information System (INIS)

    Renzini, A.

    1981-01-01

    It is generally accepted that Planetary Nebulae are produced by asymptotic giant-branch stars. Therefore, several properties of planetary nebulae are discussed in the framework of the current theory of stellar evolution. (Auth.)

  18. GTR Component of Planetary Precession

    Indian Academy of Sciences (India)

    detection of gravitational waves has only augmented their en- thusiasm about the General Theory of Relativity ... the GTR advance of the perihelion of planetary motion about the sun. 1. Introduction. When you throw an ... cury's orbit was estimated to advance by about 565 seconds of an arc per Earth-century. It is also now ...

  19. Planetary imaging with amateur astronomical instruments

    Science.gov (United States)

    Papathanasopoulos, k.; Giannaris, G.

    2017-09-01

    Planetary imaging can be varied by the types and size of instruments and processing. With basic amateur telescopes and software, can be captured images of our planetary system, mainly Jupiter, Saturn and Mars, but also solar eclipses, solar flares, and many more. Planetary photos can be useful for professional astronomers, and how amateur astronomers can play a role on that field.

  20. The Anthropocene: A Planetary Perspective

    Science.gov (United States)

    Anbar, A. D.; Hartnett, H. E.; York, A.; Selin, C.

    2016-12-01

    The Anthropocene is a new planetary epoch defined by the emergence of human activity as one of the most important driving forces on Earth, rivaling and also stressing the other systems that govern the planet's habitability. Public discussions and debates about the challenges of this epoch tend to be polarized. One extreme denies that humans have a planetary-scale impact, while the other wishes that this impact could disappear. The tension between these perspectives is often paralyzing. Effective adaptation and mitigation requires a new perspective that reframes the conversation. We propose a planetary perspective according to which this epoch is the result of a recent major innovation in the 4 ­billion ­year history of life on Earth: the emergence of an energy-intensive planetary civilization. The rate of human energy use is already within an order of magnitude of that of the rest of the biosphere, and rising rapidly, and so this innovation is second only to the evolution of photosynthesis in terms of energy capture and utilization by living systems. Such energy use has and will continue to affect Earth at planetary scale. This reality cannot be denied nor wished away. From this pragmatic perspective, the Anthropocene is not an unnatural event that can be reversed, as though humanity is separate from the Earth systems with which we are co-evolving. Rather, it is an evolutionary transition to be managed. This is the challenge of turning a carelessly altered planet into a carefully designed and managed world, maintaining a "safe operating space" for human civilization (Steffen et al., 2011). To do so, we need an integrated approach to Earth systems science that considers humans as a natural and integral component of Earth's systems. Insights drawn from the humanities and the social sciences must be integrated with the natural sciences in order to thrive in this new epoch. This type of integrated perspective is relatively uncontroversial on personal, local, and even

  1. ISO Spectroscopy of Proto-Planetary Nebulae

    Science.gov (United States)

    Hrivnak, Bruce J.

    2000-01-01

    The goal of this program was to determine the chemical properties of the dust shells around protoplanetary nebulae (PPNs) through a study of their short-wavelength (6-45 micron) infrared spectra. PPNs are evolved stars in transition from the asymptotic giant branch to the planetary nebula stages. Spectral features in the 10 to 20 gm region indicate the chemical nature (oxygen- or carbon-rich), and the strengths of the features relate to the physical properties of the shells. A few bright carbon-rich PPNs have been observed to show PAH features and an unidentified 21 micron emission feature. We used the Infrared Space Observatory (ISO) to observe a sample of IRAS sources that have the expected properties of PPNs and for which we have accurate positions. Some of these have optical counterparts (proposal SWSPPN01) and some do not (SWSPPN02). We had previously observed these from the ground with near-infrared photometry and, for those with visible counterparts, visible photometry and spectroscopy, which we have combined with these new ISO data in the interpretation of the spectra. We have completed a study of the unidentified emission feature at 21 micron in eight sources. We find the shape of the feature to be the same in all of the sources, with no evidence of any substructure. The ratio of the emission peak to continuum ranges from 0.13 to 1.30. We have completed a study of seven PPNs and two other carbon-rich objects for which we had obtained ISO 2-45 micron observations. The unidentified emission features at 21 and 30 micron were detected in six sources, including four new detections of the 30 micron feature. This previously unresolved 30 micron feature was resolved and found to consist of a broad feature peaking at 27.2 micron (the "30 micron" feature) and a narrower feature peaking at 25.5 micron (the "26 micron" feature). This new 26 micron feature is detected in eight sources and is particularly strong in IRAS Z02229+6208 and 16594-4656. The unidentified

  2. From red giants to planetary nebulae

    International Nuclear Information System (INIS)

    Kwok, S.

    1982-01-01

    The transition from red giants to planetary nebulae is studied by comparing the spectral characteristics of red giant envelopes and planetary nebulae. Observational and theoretical evidence both suggest that remnants of red giant envelopes may still be present in planetary nebula systems and should have significant effects on their formation. The dynamical effects of the interaction of stellar winds from central stars of planetary nebulae with the remnant red giant envelopes are evaluated and the mechanism found to be capable of producing the observed masses and momenta of planetary nebulae. The observed mass-radii relation of planetary nebulae may also be best explained by the interacting winds model. The possibility that red giant mass loss, and therefore the production of planetary nebulae, is different between Population I and II systems is also discussed

  3. Molecular Dications in Planetary Atmospheric Escape

    Directory of Open Access Journals (Sweden)

    Stefano Falcinelli

    2016-08-01

    Full Text Available Fundamental properties of multiply charged molecular ions, such as energetics, structure, stability, lifetime and fragmentation dynamics, are relevant to understand and model the behavior of gaseous plasmas as well as ionosphere and astrophysical environments. Experimental determinations of the Kinetic Energy Released (KER for ions originating from dissociations reactions, induced by Coulomb explosion of doubly charged molecular ions (molecular dications produced by double photoionization of CO2, N2O and C2H2 molecules of interest in planetary atmospheres, are reported. The KER measurement as a function of the ultraviolet (UV photon energy in the range of 28–65 eV was extracted from the electron-ion-ion coincidence spectra obtained by using tunable synchrotron radiation coupled with ion imaging techniques at the ELETTRA Synchrotron Light Laboratory Trieste, Italy. These experiments, coupled with a computational analysis based on a Monte Carlo trajectory simulation, allow assessing the probability of escape for simple ionic species in the upper atmosphere of Mars, Venus and Titan. The measured KER in the case of H+, C+, CH+, CH2+, N+, O+, CO+, N2+ and NO+ fragment ions range between 1.0 and 5.5 eV, being large enough to allow these ionic species to participate in the atmospheric escape from such planets into space. In the case of Mars, we suggest a possible explanation for the observed behavior of the O+ and CO22+ ion density profiles.

  4. Optimizing bandpasses to separate planetary bodies

    Science.gov (United States)

    Teal, Dillon J.; Yarber, Aara'L.; Kopparapu, Ravi; Arney, Giada; Roberge, Aki

    2018-01-01

    Future telescopes will be able to directly image exoplants, opening up a new era in comparative planteology. However, background point sources, including stars, brown dwarfs, and distant unresolved galaxies may be confused with planetary sources. Observing time is previous, and methods are needed to efficiently and effectively distinguish between exoplanets and background objects. We present an optimized strategy using multi-color point source photometry to distinguish planets from the background objects with the greatest potential for spectral confusion. By determining which photometric bandpasses most effectively separate planets from background sources, this strategy would enable optimization of future telescope designs. Such an approach is key to quickly characterizing a planet while minimizing observation time. To find this optimized strategy, we used comparative spectroscopy alongside linear regression and Markov Chain Monte-Carlo (MCMC) retrieval to identify the optimal bandpasses for the LUVOIR (Large UV-Optical-Infrared Telescope) mission study coronagraph. We consider bandpasses that maximize the color-color separation of background objects from planets; we also investigate the effectiveness of color photometry to distinguish between different classes of planets using Solar System and observed spectra. This optimization strategy would also be useful to other direct imaging missions, such as HabEx, and could in principle be applied to transit spectroscopy missions, such as JWST, ARIEL, and OST.

  5. Spectra of Graphs

    NARCIS (Netherlands)

    Brouwer, A.E.; Haemers, W.H.

    2012-01-01

    This book gives an elementary treatment of the basic material about graph spectra, both for ordinary, and Laplace and Seidel spectra. The text progresses systematically, by covering standard topics before presenting some new material on trees, strongly regular graphs, two-graphs, association

  6. Spectra of alkali atoms

    International Nuclear Information System (INIS)

    Santoso, Budi; Arumbinang, Haryono.

    1981-01-01

    Emission spectra of alkali atoms has been determined by using spectrometer at the ultraviolet to infra red waves range. The spectra emission can be obtained by absorption spectrophotometric analysis. Comparative evaluations between experimental data and data handbook obtained by spark method were also presented. (author tr.)

  7. Solar Variability and Planetary Climates

    CERN Document Server

    Calisesi, Y; Gray, L; Langen, J; Lockwood, M

    2007-01-01

    Variations in solar activity, as revealed by variations in the number of sunspots, have been observed since ancient times. To what extent changes in the solar output may affect planetary climates, though, remains today more than ever a subject of controversy. In 2000, the SSSI volume on Solar Variability and Climate reviewed the to-date understanding of the physics of solar variability and of the associated climate response. The present volume on Solar Variability and Planetary Climates provides an overview of recent advances in this field, with particular focus at the Earth's middle and lower atmosphere. The book structure mirrors that of the ISSI workshop held in Bern in June 2005, the collection of invited workshop contributions and of complementary introductory papers synthesizing the current understanding in key research areas such as middle atmospheric processes, stratosphere-troposphere dynamical coupling, tropospheric aerosols chemistry, solar storm influences, solar variability physics, and terrestri...

  8. Teaching, Learning, and Planetary Exploration

    Science.gov (United States)

    Brown, Robert A.

    2002-01-01

    This is the final report of a program that examined the fundamentals of education associated with space activities, promoted educational policy development in appropriate forums, and developed pathfinder products and services to demonstrate the utility of advanced communication technologies for space-based education. Our focus was on space astrophysics and planetary exploration, with a special emphasis on the themes of the Origins Program, with which the Principal Investigator (PI) had been involved from the outset. Teaching, Learning, and Planetary Exploration was also the core funding of the Space Telescope Science Institute's (ST ScI) Special Studies Office (SSO), and as such had provided basic support for such important NASA studies as the fix for Hubble Space Telescope (HST) spherical aberration, scientific conception of the HST Advanced Camera, specification of the Next-Generation Space Telescope (NGST), and the strategic plan for the second decade of the HST science program.

  9. The PSA: Planetary Science Archive

    Science.gov (United States)

    Barthelemy, M.; Martinez, S.; Heather, D.; Vazquez, J. L.; Arviset, C.; Osuna, P.; PSA development Team

    2012-04-01

    Scientific and engineering data from ESA's planetary missions are made accessible to the world-wide scientific community via the Planetary Science Archive (PSA). The PSA consists of online services incorporating search, preview, download, notification and delivery basket functionality. Besides data from the GIOTTO spacecraft and several ground-based cometary observations, the PSA contains data from the Mars Express, Venus Express, Rosetta, SMART-1 and Huygens missions. The focus of the PSA activities is on the long-term preservation of data and knowledge from ESA's planetary missions. Scientific users can access the data online using several interfaces: - The Advanced Search Interface allows complex parameter based queries, providing the end user with a facility to complete very specific searches on meta-data and geometrical parameters. By nature, this interface requires careful use and heavy interaction with the end-user to input and control the relevant search parameters. - The Map-based Interface is currently operational only for Mars Express HRCS and OMEGA data. This interface allows an end-user to specify a region-of-interest by dragging a box onto a base map of Mars. From this interface, it is possible to directly visualize query results. The Map-based and Advanced interfaces are linked and cross-compatible. If a user defines a region-of-interest in the Map-based interface, the results can be refined by entering more detailed search parameters in the Advanced interface. - The FTP Browser Interface is designed for more experienced users, and allows for direct browsing and access of the data set content through ftp-tree search. Each dataset contains documentation and calibration information in addition to the scientific or engineering data. All data are prepared by the corresponding instrument teams, mostly located in Europe. PSA supports the instrument teams in the full archiving process, from the definition of the data products, meta-data and product labels

  10. Numerical models of planetary dynamos

    International Nuclear Information System (INIS)

    Glatzmaier, G.A.; Roberts, P.H.

    1992-01-01

    We describe a nonlinear, axisymmetric, spherical-shell model of planetary dynamos. This intermediate-type dynamo model requires a prescribed helicity field (the alpha effect) and a prescribed buoyancy force or thermal wind (the omega effect) and solves for the axisymmetric time-dependent magnetic and velocity fields. Three very different time dependent solutions are obtained from different prescribed sets of alpha and omega fields

  11. Stream Lifetimes Against Planetary Encounters

    Science.gov (United States)

    Valsecchi, G. B.; Lega, E.; Froeschle, Cl.

    2011-01-01

    We study, both analytically and numerically, the perturbation induced by an encounter with a planet on a meteoroid stream. Our analytical tool is the extension of pik s theory of close encounters, that we apply to streams described by geocentric variables. The resulting formulae are used to compute the rate at which a stream is dispersed by planetary encounters into the sporadic background. We have verified the accuracy of the analytical model using a numerical test.

  12. Planetary rovers and data fusion

    OpenAIRE

    Masuku, Anthony Dumisani

    2012-01-01

    This research will investigate the problem of position estimation for planetary rovers. Diverse algorithmic filters are available for collecting input data and transforming that data to useful information for the purpose of position estimation process. The terrain has sandy soil which might cause slipping of the robot, and small stones and pebbles which can affect trajectory. The Kalman Filter, a state estimation algorithm was used for fusing the sensor data to improve the p...

  13. Gazetteer of planetary nomenclature 1994

    Science.gov (United States)

    Batson, Raymond M.; Russell, Joel F.

    1995-01-01

    Planetary nomenclature, like terrestrial nomenclature, is used to uniquely identify a feature on the surface of a planet or satellite so that the feature can be easily located, described, and discussed. This volume contains detailed information about all names of topographic and albedo features on planets and satellites (and some planetary ring and ring-gap systems) that the International Astronomical Union has named and approved from its founding in 1919 through its triennial meeting in 1994.This edition of the Gazetteer of Planetary Nomenclature supersedes an earlier informal volume distributed by the U.S. Geological Survey in 1986 as Open-File Report 84-692 (Masursky and others, 1986). Named features are depicted on maps of the Moon published first by the U.S. Defense Mapping Agency or the Aeronautical Chart and Information Center and more recently by the U.S. Geological Survey; on maps of Mercury, Venus, Mars, and the satellites of Jupiter, Saturn, and Uranus published by the U.S. Geological Survey; and on maps of the Moon, Venus, and Mars produced by the U.S.S.R.Although we have attempted to check the accuracy of all data in this volume, we realize that some errors will remain in a work of this size. Readers noting errors or omissions are urged to communicate them to the U.S. Geological Survey, Branch of Astrogeology, Rm. 409, 2255 N. Gemini Drive, Flagstaff, AZ 86001.

  14. Evolution of planetary nebula nuclei

    International Nuclear Information System (INIS)

    Shaw, R.A.

    1985-01-01

    The evolution of planetary nebula nuclei (PNNs) is examined with the aid of the most recent available stellar evolution calculations and new observations of these objects. Their expected distribution in the log L-log T plane is calculated based upon the stellar evolutionary models of Paczynski, Schoenberner and Iben, the initial mass function derived by Miller and Scalo, and various assumptions concerning mass loss during post-main sequence evolution. The distribution is found to be insensitive both to the assumed range of main-sequence progenitor mass and to reasonable variations in the age and the star forming history of the galactic disk. Rather, the distribution is determined by the strong dependence of the rate of stellar evolution upon core mass, the steepness of the initial mass function, and to a lesser extent the finite lifetime of an observable planetary nebula. The theoretical distributions are rather different than any of those inferred from earlier observations. Possible observational selection effects that may be responsible are examined, as well as the intrinsic uncertainties associated with the theoretical model predictions. An extensive photometric and smaller photographic survey of southern hemisphere planetary nebulae (PNs) is presented

  15. Planetary nebulae: understanding the physical and chemical evolution of dying stars.

    Science.gov (United States)

    Weinberger, R; Kerber, F

    1997-05-30

    Planetary nebulae are one of the few classes of celestial objects that are active in every part of the electromagnetic spectrum. These fluorescing and often dusty expanding gaseous envelopes were recently found to be quite complex in their dynamics and morphology, but refined theoretical models can account for these discoveries. Great progress was also made in understanding the mechanisms that shape the nebulae and the spectra of their central stars. In addition, applications for planetary nebulae have been worked out; for example, they have been used as standard candles for long-range distances and as tracers of the enigmatic dark matter.

  16. Collisional stripping of planetary crusts

    Science.gov (United States)

    Carter, Philip J.; Leinhardt, Zoë M.; Elliott, Tim; Stewart, Sarah T.; Walter, Michael J.

    2018-02-01

    Geochemical studies of planetary accretion and evolution have invoked various degrees of collisional erosion to explain differences in bulk composition between planets and chondrites. Here we undertake a full, dynamical evaluation of 'crustal stripping' during accretion and its key geochemical consequences. Crusts are expected to contain a significant fraction of planetary budgets of incompatible elements, which include the major heat producing nuclides. We present smoothed particle hydrodynamics simulations of collisions between differentiated rocky planetesimals and planetary embryos. We find that the crust is preferentially lost relative to the mantle during impacts, and we have developed a scaling law based on these simulations that approximates the mass of crust that remains in the largest remnant. Using this scaling law and a recent set of N-body simulations of terrestrial planet formation, we have estimated the maximum effect of crustal stripping on incompatible element abundances during the accretion of planetary embryos. We find that on average approximately one third of the initial crust is stripped from embryos as they accrete, which leads to a reduction of ∼20% in the budgets of the heat producing elements if the stripped crust does not reaccrete. Erosion of crusts can lead to non-chondritic ratios of incompatible elements, but the magnitude of this effect depends sensitively on the details of the crust-forming melting process on the planetesimals. The Lu/Hf system is fractionated for a wide range of crustal formation scenarios. Using eucrites (the products of planetesimal silicate melting, thought to represent the crust of Vesta) as a guide to the Lu/Hf of planetesimal crust partially lost during accretion, we predict the Earth could evolve to a superchondritic 176Hf/177Hf (3-5 parts per ten thousand) at present day. Such values are in keeping with compositional estimates of the bulk Earth. Stripping of planetary crusts during accretion can lead to

  17. Torsional vibration signal analysis as a diagnostic tool for planetary gear fault detection

    Science.gov (United States)

    Xue, Song; Howard, Ian

    2018-02-01

    This paper aims to investigate the effectiveness of using the torsional vibration signal as a diagnostic tool for planetary gearbox faults detection. The traditional approach for condition monitoring of the planetary gear uses a stationary transducer mounted on the ring gear casing to measure all the vibration data when the planet gears pass by with the rotation of the carrier arm. However, the time variant vibration transfer paths between the stationary transducer and the rotating planet gear modulate the resultant vibration spectra and make it complex. Torsional vibration signals are theoretically free from this modulation effect and therefore, it is expected to be much easier and more effective to diagnose planetary gear faults using the fault diagnostic information extracted from the torsional vibration. In this paper, a 20 degree of freedom planetary gear lumped-parameter model was developed to obtain the gear dynamic response. In the model, the gear mesh stiffness variations are the main internal vibration generation mechanism and the finite element models were developed for calculation of the sun-planet and ring-planet gear mesh stiffnesses. Gear faults on different components were created in the finite element models to calculate the resultant gear mesh stiffnesses, which were incorporated into the planetary gear model later on to obtain the faulted vibration signal. Some advanced signal processing techniques were utilized to analyses the fault diagnostic results from the torsional vibration. It was found that the planetary gear torsional vibration not only successfully detected the gear fault, but also had the potential to indicate the location of the gear fault. As a result, the planetary gear torsional vibration can be considered an effective alternative approach for planetary gear condition monitoring.

  18. SAWYER ASTEROID SPECTRA

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains 94 optical asteroid spectra obtained by Scott Sawyer as part of his Ph.D. dissertation at the University of Texas at Austin. Observational...

  19. The Planetary Data System— Archiving Planetary Data for the use of the Planetary Science Community

    Science.gov (United States)

    Morgan, Thomas H.; McLaughlin, Stephanie A.; Grayzeck, Edwin J.; Vilas, Faith; Knopf, William P.; Crichton, Daniel J.

    2014-11-01

    NASA’s Planetary Data System (PDS) archives, curates, and distributes digital data from NASA’s planetary missions. PDS provides the planetary science community convenient online access to data from NASA’s missions so that they can continue to mine these rich data sets for new discoveries. The PDS is a federated system consisting of nodes for specific discipline areas ranging from planetary geology to space physics. Our federation includes an engineering node that provides systems engineering support to the entire PDS.In order to adequately capture complete mission data sets containing not only raw and reduced instrument data, but also calibration and documentation and geometry data required to interpret and use these data sets both singly and together (data from multiple instruments, or from multiple missions), PDS personnel work with NASA missions from the initial AO through the end of mission to define, organize, and document the data. This process includes peer-review of data sets by members of the science community to ensure that the data sets are scientifically useful, effectively organized, and well documented. PDS makes the data in PDS easily searchable so that members of the planetary community can both query the archive to find data relevant to specific scientific investigations and easily retrieve the data for analysis. To ensure long-term preservation of data and to make data sets more easily searchable with the new capabilities in Information Technology now available (and as existing technologies become obsolete), the PDS (together with the COSPAR sponsored IPDA) developed and deployed a new data archiving system known as PDS4, released in 2013. The LADEE, MAVEN, OSIRIS REx, InSight, and Mars2020 missions are using PDS4. ESA has adopted PDS4 for the upcoming BepiColumbo mission. The PDS is actively migrating existing data records into PDS4 and developing tools to aid data providers and users. The PDS is also incorporating challenge

  20. Teaching, learning, and planetary exploration

    Science.gov (United States)

    Brown, Robert A.

    1992-01-01

    The progress accomplished in the first five months of the three-year grant period of Teaching, Learning, and Planetary Exploration is presented. The objectives of this project are to discover new education products and services based on space science, particularly planetary exploration. An Exploration in Education is the umbrella name for the education projects as they are seen by teachers and the interested public. As described in the proposal, our approach consists of: (1) increasing practical understanding of the potential role and capabilities of the research community to contribute to basic education using new discoveries; (2) developing an intellectual framework for these contributions by supplying criteria and templates for the teacher's stories; (3) attracting astronomers, engineers, and technical staff to the project and helping them form productive education partnerships for the future, (4) exploring relevant technologies and networks for authoring and communicating the teacher's stories; (5) enlisting the participation of potential user's of the teacher's stories in defining the products; (6) actually producing and delivering many educationally useful teacher's stories; and (7) reporting the pilot study results with critical evaluation. Technical progress was made by assembling our electronic publishing stations, designing electronic publications based on space science, and developing distribution approaches for electronic products. Progress was made addressing critical issues by developing policies and procedures for securing intellectual property rights and assembling a focus group of teachers to test our ideas and assure the quality of our products. The following useful materials are being produced: the TOPS report; three electronic 'PictureBooks'; one 'ElectronicArticle'; three 'ElectronicReports'; ten 'PrinterPosters'; and the 'FaxForum' with an initial complement of printed materials. We have coordinated with planetary scientists and astronomers

  1. Institute of Geophysics, Planetary Physics, and Signatures

    Data.gov (United States)

    Federal Laboratory Consortium — The Institute of Geophysics, Planetary Physics, and Signatures at Los Alamos National Laboratory is committed to promoting and supporting high quality, cutting-edge...

  2. Sealed Planetary Return Canister (SPRC), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Sample return missions have primary importance in future planetary missions. A basic requirement is that samples be returned in pristine, uncontaminated condition,...

  3. Polarimetry of stars and planetary systems

    National Research Council Canada - National Science Library

    Kolokolova, Ludmilla; Hough, James; Levasseur-Regourd, Anny-Chantal

    2015-01-01

    ... fields of polarimetric exploration, including proto-planetary and debris discs, icy satellites, transneptunian objects, exoplanets and the search for extraterrestrial life -- unique results produced...

  4. Sealed Planetary Return Canister (SPRC), Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Sample return missions have primary importance in future planetary missions. A basic requirement is that samples be returned in pristine, uncontaminated condition,...

  5. Public Participation in Planetary Exploration

    Science.gov (United States)

    Friedman, Louis

    2000-07-01

    In the past several years The Planetary Society has created several innovative opportunities for general public participation in the exploration of the solar system and the search for extraterrestrial life. The conduct of such exploration has traditionally been the province of a few thousand, at most, of professionally involved scientists and engineers. Yet the rationale for spending resources required by broad and far-reaching exploration involves a greater societal interest - it frequently being noted that the rationale cannot rely on science alone. This paper reports on the more notable of the opportunities for general public participation, in particular: 1) Visions of Mars: a CD containing the works of science fiction about Mars, designed to be placed on Mars as the first library to be found by eventual human explorers; 2) MAPEX: a Microelectronics And Photonics Experiment, measuring the radiation environment for future human explorers of Mars, and containing a electron beam lithograph of names of all the members of The Planetary Society at a particular time; 3) Naming of spacecraft: Involvement in the naming of spacecraft: Magellan, Sojourner; 4) The Mars Microphone: the first privately funded instrument to be sent to another world; 5) Red Rover Goes to Mars: the first commercial-education partnership on a planetary mission; 6) Student designed nanoexperiments: to fly on a Mars lander; and 7) SETI@home: a tool permitting millions to contribute to research and data processing in the search for extraterrestrial intelligence. A brief description of each of the projects will be given, and the opportunity it provided for public participation described. The evolving complexity of these projects suggest that more opportunities will be found, and that the role of public participation can increase at the same time as making substantive contributions to the flight missions. It will be suggested that these projects presage the day that planetary exploration will be truly

  6. Planetary Radars Operating Centre PROC

    Science.gov (United States)

    Catallo, C.; Flamini, E.; Seu, R.; Alberti, G.

    2007-12-01

    Planetary exploration by means of radar systems, mainly using Ground Penetrating Radars (GPR) plays an important role in Italy. Numerous scientific international space programs are currently carried out jointly with ESA and NASA by Italian Space Agency, the scientific community and the industry. Three important experiments under Italian leadership ( designed and manufactured by the Italian industry), provided by ASI either as contribution to ESA programs either within a NASA/ASI joint venture framework, are now operating: MARSIS on-board Mars Express, SHARAD on-board Mars Reconnaissance Orbiter and CASSINI Radar on-board Cassini spacecraft. In order to support all the scientific communities, institutional customers and experiment teams operation three Italian dedicated operational centers have been realized, namely SHOC, (Sharad Operating Centre), MOC (Marsis Operating Center) and CASSINI PAD ( Processing Altimetry Data). Each center is dedicated to a single instrument management and control, data processing and distribution. Although they had been conceived to operate autonomously and independently one from each other, synergies and overlaps have been envisaged leading to the suggestion of a unified center, the Planetary Radar Processing Center (PROC). PROC is conceived in order to include the three operational centers, namely SHOC, MOC and CASSINI PAD, either from logistics point of view and from HW/SW capabilities point of view. The Planetary Radar Processing Center shall be conceived as the Italian support facility to the scientific community for on-going and future Italian planetary exploration programs. Therefore, scalability, easy use and management shall be the design drivers. The paper describes how PROC is designed and developed, to allow SHOC, MOC and CASSINI PAD to operate as before, and to offer improved functionalities to increase capabilities, mainly in terms of data exchange, comparison, interpretation and exploitation. Furthermore, in the frame of

  7. Energetic Techniques For Planetary Defense

    Science.gov (United States)

    Barbee, B.; Bambacus, M.; Bruck Syal, M.; Greenaugh, K. C.; Leung, R. Y.; Plesko, C. S.

    2017-12-01

    Near-Earth Objects (NEOs) are asteroids and comets whose heliocentric orbits tend to approach or cross Earth's heliocentric orbit. NEOs of various sizes periodically collide with Earth, and efforts are currently underway to discover, track, and characterize NEOs so that those on Earth-impacting trajectories are discovered far enough in advance that we would have opportunities to deflect or destroy them prior to Earth impact, if warranted. We will describe current efforts by the National Aeronautics and Space Administration (NASA) and the National Nuclear Security Administration (NNSA) to assess options for energetic methods of deflecting or destroying hazardous NEOs. These methods include kinetic impactors, which are spacecraft designed to collide with an NEO and thereby alter the NEO's trajectory, and nuclear engineering devices, which are used to rapidly vaporize a layer of NEO surface material. Depending on the amount of energy imparted, this can result in either deflection of the NEO via alteration of its trajectory, or robust disruption of the NEO and dispersal of the remaining fragments. We have studied the efficacies and limitations of these techniques in simulations, and have combined the techniques with corresponding spacecraft designs and mission designs. From those results we have generalized planetary defense mission design strategies and drawn conclusions that are applicable to a range of plausible scenarios. We will present and summarize our research efforts to date, and describe approaches to carrying out planetary defense missions with energetic NEO deflection or disruption techniques.

  8. Interactive investigations into planetary interiors

    Science.gov (United States)

    Rose, I.

    2015-12-01

    Many processes in Earth science are difficult to observe or visualize due to the large timescales and lengthscales over which they operate. The dynamics of planetary mantles are particularly challenging as we cannot even look at the rocks involved. As a result, much teaching material on mantle dynamics relies on static images and cartoons, many of which are decades old. Recent improvements in computing power and technology (largely driven by game and web development) have allowed for advances in real-time physics simulations and visualizations, but these have been slow to affect Earth science education.Here I demonstrate a teaching tool for mantle convection and seismology which solves the equations for conservation of mass, momentum, and energy in real time, allowing users make changes to the simulation and immediately see the effects. The user can ask and answer questions about what happens when they add heat in one place, or take it away from another place, or increase the temperature at the base of the mantle. They can also pause the simulation, and while it is paused, create and visualize seismic waves traveling through the mantle. These allow for investigations into and discussions about plate tectonics, earthquakes, hot spot volcanism, and planetary cooling.The simulation is rendered to the screen using OpenGL, and is cross-platform. It can be run as a native application for maximum performance, but it can also be embedded in a web browser for easy deployment and portability.

  9. Visual lunar and planetary astronomy

    CERN Document Server

    Abel, Paul G

    2013-01-01

    With the advent of CCDs and webcams, the focus of amateur astronomy has to some extent shifted from science to art. The object of many amateur astronomers is now to produce “stunning images” that, although beautiful, are not intended to have scientific merit. Paul Abel has been addressing this issue by promoting visual astronomy wherever possible – at talks to astronomical societies, in articles for popular science magazines, and on BBC TV’s The Sky at Night.   Visual Lunar and Planetary Astronomy is a comprehensive modern treatment of visual lunar and planetary astronomy, showing that even in the age of space telescopes and interplanetary probes it is still possible to contribute scientifically with no more than a moderately priced commercially made astronomical telescope.   It is believed that imaging and photography is somehow more objective and more accurate than the eye, and this has led to a peculiar “crisis of faith” in the human visual system and its amazing processing power. But by anal...

  10. Solar Energetic Particle Spectra

    Science.gov (United States)

    Ryan, J. M.; Boezio, M.; Bravar, U.; Bruno, A.; Christian, E. R.; de Nolfo, G. A.; Martucci, M.; Mergè, M.; Munini, R.; Ricci, M.; Sparvoli, R.; Stochaj, S.

    2017-12-01

    We report updated event-integrated spectra from several SEP events measured with PAMELA. The measurements were made from 2006 to 2014 in the energy range starting at 80 MeV and extending well above the neutron monitor threshold. The PAMELA instrument is in a high inclination, low Earth orbit and has access to SEPs when at high latitudes. Spectra have been assembled from these high-latitude measurements. The field of view of PAMELA is small and during the high-latitude passes it scans a wide range of asymptotic directions as the spacecraft orbits. Correcting for data gaps, solid angle effects and improved background corrections, we have compiled event-integrated intensity spectra for twenty-eight SEP events. Where statistics permit, the spectra exhibit power law shapes in energy with a high-energy exponential roll over. The events analyzed include two genuine ground level enhancements (GLE). In those cases the roll-over energy lies above the neutron monitor threshold ( 1 GV) while the others are lower. We see no qualitative difference between the spectra of GLE vs. non-GLE events, i.e., all roll over in an exponential fashion with rapidly decreasing intensity at high energies.

  11. Lunar and Planetary Science XXXVI, Part 18

    Science.gov (United States)

    2005-01-01

    Topics discussed include: PoDS: A Powder Delivery System for Mars In-Situ Organic, Mineralogic and Isotopic Analysis Instruments Planetary Differentiation of Accreting Planetesimals with 26Al and 60Fe as the Heat Sources Ground-based Observation of Lunar Surface by Lunar VIS/NIR Spectral Imager Mt. Oikeyama Structure: First Impact Structure in Japan? Central Mounds in Martian Impact Craters: Assessment as Possible Perennial Permafrost Mounds (Pingos) A Further Analysis of Potential Photosynthetic Life on Mars New Insight into Valleys-Ocean Boundary on Mars Using 128 Pixels per Degree MOLA Data: Implication for Martian Ocean and Global Climate Change; Recursive Topography Based Surface Age Computations for Mars: New Insight into Surficial Processes That Influenced Craters Distribution as a Step Toward the Formal Proof of Martian Ocean Recession, Timing and Probability; Laser-induced Breakdown Spectroscopy: A New Method for Stand-Off Quantitative Analysis of Samples on Mars; Milk Spring Channels Provide Further Evidence of Oceanic, >1.7-km-Deep Late Devonian Alamo Crater, Southern Nevada; Exploration of Martian Polar Residual Caps from HEND/ODYSSEY Data; Outflow Channels Influencing Martian Climate: Global Circulation Model Simulations with Emplaced Water; Presence of Nonmethane Hydrocarbons on Pluto; Difference in Degree of Space Weathering on the Newborn Asteroid Karin; Circular Collapsed Features Related to the Chaotic Terrain Formation on Mars; A Search for Live (sup 244)Pu in Deep-Sea Sediments: Preliminary Results of Method Development; Some Peculiarities of Quartz, Biotite and Garnet Transformation in Conditions of Step-like Shock Compression of Crystal Slate; Error Analysis of Remotely-Acquired Mossbauer Spectra; Cloud Activity on Titan During the Cassini Mission; Solar Radiation Pressure and Transient Flows on Asteroid Surfaces; Landing Site Characteristics for Europa 1: Topography; and The Crop Circles of Europa.

  12. PLANETARY CANDIDATES FROM THE FIRST YEAR OF THE K2 MISSION

    Energy Technology Data Exchange (ETDEWEB)

    Vanderburg, Andrew; Latham, David W.; Bieryla, Allyson; Berlind, Perry; Calkins, Michael L.; Esquerdo, Gilbert A.; Welsh, Sophie; Johnson, John Asher [Harvard–Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States); Buchhave, Lars A., E-mail: avanderburg@cfa.harvard.edu [Centre for Star and Planet Formation, Natural History Museum of Denmark and Niels Bohr Institute, University of Copenhagen, Øster Voldgade 5-7, DK-1350 Copenhagen K (Denmark)

    2016-01-15

    The Kepler Space Telescope is currently searching for planets transiting stars along the ecliptic plane as part of its extended K2 mission. We processed the publicly released data from the first year of K2 observations (Campaigns 0, 1, 2, and 3) and searched for periodic eclipse signals consistent with planetary transits. Out of the 59,174 targets that we searched, we detect 234 planetary candidates around 208 stars. These candidates range in size from gas giants to smaller than the Earth, and range in orbital periods from hours to over a month. We conducted initial reconnaissance spectroscopy of 68 of the brighter candidate host stars, and present high-resolution optical spectra for these stars. We make all of our data products, including light curves, spectra, and vetting diagnostics available to users online.

  13. Visualization of Kepler's Laws of Planetary Motion

    Science.gov (United States)

    Lu, Meishu; Su, Jun; Wang, Weiguo; Lu, Jianlong

    2017-01-01

    For this article, we use a 3D printer to print a surface similar to universal gravitation for demonstrating and investigating Kepler's laws of planetary motion describing the motion of a small ball on the surface. This novel experimental method allows Kepler's laws of planetary motion to be visualized and will contribute to improving the…

  14. Preparing Planetary Scientists to Engage Audiences

    Science.gov (United States)

    Shupla, C. B.; Shaner, A. J.; Hackler, A. S.

    2017-12-01

    While some planetary scientists have extensive experience sharing their science with audiences, many can benefit from guidance on giving presentations or conducting activities for students. The Lunar and Planetary Institute (LPI) provides resources and trainings to support planetary scientists in their communication efforts. Trainings have included sessions for students and early career scientists at conferences (providing opportunities for them to practice their delivery and receive feedback for their poster and oral presentations), as well as separate communication workshops on how to engage various audiences. LPI has similarly begun coaching planetary scientists to help them prepare their public presentations. LPI is also helping to connect different audiences and their requests for speakers to planetary scientists. Scientists have been key contributors in developing and conducting activities in LPI education and public events. LPI is currently working with scientists to identify and redesign short planetary science activities for scientists to use with different audiences. The activities will be tied to fundamental planetary science concepts, with basic materials and simple modifications to engage different ages and audience size and background. Input from the planetary science community on these efforts is welcome. Current results and resources, as well as future opportunities will be shared.

  15. Introduction to the special issue: Planetary geomorphology

    Science.gov (United States)

    Burr, Devon M.; Howard, Alan D.

    2015-07-01

    Planetary geomorphology is the study of extraterrestrial landscapes. In recognition of the promise for productive interaction between terrestrial and planetary geomorphologists, the 45th annual Binghamton Geomorphology Symposium (BGS) focused on Planetary Geomorphology. The aim of the symposium was to bring planetary and terrestrial geomorphologists together for symbiotic and synthetic interactions that would enrich both subdisciplines. In acknowledgment of the crucial role of terrestrial field work in planetary geomorphology and of the BGS tradition, the symposium began with a field trip to the Appalachian Mountains, followed by a dinner talk of recent results from the Mars Surface Laboratory. On Saturday and Sunday, the symposium was organized around major themes in planetary geomorphology, starting with the geomorphic processes that are most common in our Solar System-impact cratering, tectonism, volcanism-to set the stage for other geomorphic processes, including aeolian, fluvial, lacustrine, and glacial/polar. On Saturday evening, the banquet talk provided an historical overview of planetary geomorphology, including its roots in the terrestrial geosciences. The symposium concluded with a full-afternoon tutorial on planetary geomorphologic datasets. This special issue of Geomorphology consists of papers by invited authors from the 2014 BGS, and this introduction provides some context for these papers.

  16. Interoperability in the Planetary Science Archive (PSA)

    Science.gov (United States)

    Rios Diaz, C.

    2017-09-01

    The protocols and standards currently being supported by the recently released new version of the Planetary Science Archive at this time are the Planetary Data Access Protocol (PDAP), the EuroPlanet- Table Access Protocol (EPN-TAP) and Open Geospatial Consortium (OGC) standards. We explore these protocols in more detail providing scientifically useful examples of their usage within the PSA.

  17. Planetary CubeSats Come of Age

    Science.gov (United States)

    Sherwood, Brent; Spangelo, Sara; Frick, Andreas; Castillo-Rogez, Julie; Klesh, Andrew; Wyatt, E. Jay; Reh, Kim; Baker, John

    2015-01-01

    Jet Propulsion Laboratory initiatives in developing and formulating planetary CubeSats are described. Six flight systems already complete or underway now at JPL for missions to interplanetary space, the Moon, a near-Earth asteroid, and Mars are described at the subsystem level. Key differences between interplanetary nanospacecraft and LEO CubeSats are explained, as well as JPL's adaptation of vendor components and development of system solutions to meet planetary-mission needs. Feasible technology-demonstration and science measurement objectives are described for multiple modes of planetary mission implementation. Seven planetary-science demonstration mission concepts, already proposed to NASA by Discovery-2014 PIs partnered with JPL, are described for investigations at Sun-Earth L5, Venus, NEA 1999 FG3, comet Tempel 2, Phobos, main-belt asteroid 24 Themis, and metal asteroid 16 Psyche. The JPL staff and facilities resources available to PIs for analysis, design, and development of planetary nanospacecraft are catalogued.

  18. On the temperature dependence of possible S8 infrared bands in planetary atmospheres

    Science.gov (United States)

    Khare, B. N.; Sagan, C.

    1977-01-01

    The temperature dependence between 77 and 333 K of the infrared spectrum of cyclic S8 in the Jupiter atmosphere has been measured. It was found that the 23-micron Jovian feature (identified by Houck et al., 1975), if real, cannot be attributed to cyclic S8. Other features of S8, however, such as the band with a room-temperature central frequency of 835/cm may prove to be useful temperature calibrators in planetary or satellite spectra.

  19. Spectroscopy in the study of planetary atmospheres - Abundances from the visible region

    Science.gov (United States)

    Lutz, B. L.

    1978-01-01

    Spectrophotometric studies of three molecular constituents - hydrogen, methane, and ammonia - identified in the visible region of the spectra of the outer planets are reviewed. The history of quadrupole line observations for hydrogen molecules and the significance of the HD molecule for the dipole spectrum are considered. Approaches to quantitative estimates of methane concentration in planetary atmospheres are explained, and the detection of ammonia in the atmospheres of Jupiter and Saturn is described.

  20. Luminosity function for planetary nebulae and the number of planetary nebulae in local group galaxies

    International Nuclear Information System (INIS)

    Jacoby, G.H.

    1980-01-01

    Identifications of 19 and 34 faint planetary nebulae have been made in the central regions of the SMC and LMC, respectively, using on-line/off-line filter photography at [O III] and Hα. The previously known brighter planetary nebulae in these fields, eight in both the SMC and the LMC, were also identified. On the basis of the ratio of the numbers of faint to bright planetary nebulae in these fields and the numbers of bright planetary nebulae in the surrounding fields, the total numbers of planetary nebulae in the SMC and LMC are estimated to be 285 +- 78 and 996 +- 253, respectively. Corrections have been applied to account for omissions due to crowding confusion in previous surveys, spatial and detectability incompleteness, and obscuration by dust.Equatorial coordinates and finding charts are presented for all the identified planetary nebulae. The coordinates have uncertainties smaller than 0.''6 relative to nearby bright stars, thereby allowing acquisition of the planetary nebulae by bling offsetting.Monochromatic fluxes are derived photographically and used to determine the luminosity function for Magellanic Cloud planetary nebulae as faint as 6 mag below the brightest. The luminosity function is used to estimate the total numbers of planetary nebulae in eight Local Group galaxies in which only bright planetary nebulae have been identified. The dervied luminosity specific number of planetary nebulae per unit luminosity is nearly constant for all eight galaxies, having a value of 6.1 x 10 -7 planetary nebulae L -1 /sub sun/. The mass specific number, based on the three galaxies with well-determined masses, is 2.1 x 10 -7 planetary nebulae M -1 /sub sun/. With estimates for the luminosity and mass of our Galaxy, its total number of planetary nebulae is calculated to be 10,000 +- 4000, in support of the Cudworth distance scale

  1. Parameterization of rotational spectra

    International Nuclear Information System (INIS)

    Zhou Chunmei; Liu Tong

    1992-01-01

    The rotational spectra of the strongly deformed nuclei with low rotational frequencies and weak band mixture are analyzed. The strongly deformed nuclei are commonly encountered in the rare-earth region (e. g., 150 220). A lot of rotational band knowledge are presented

  2. Atomic Spectra Database (ASD)

    Science.gov (United States)

    SRD 78 NIST Atomic Spectra Database (ASD) (Web, free access)   This database provides access and search capability for NIST critically evaluated data on atomic energy levels, wavelengths, and transition probabilities that are reasonably up-to-date. The NIST Atomic Spectroscopy Data Center has carried out these critical compilations.

  3. Interferometric observations of planetary nebulae

    International Nuclear Information System (INIS)

    Atherton, P.D.

    1978-01-01

    Studies of the velocity field of planetary nebulae can be used to derive important information concerning their structure and dynamics. A description is given of the design, construction and operation of a servo-controlled Fabry Perot Interferometer, for the Cassegrain focus, which was built to perform these studies. New evidence is presented concerning the structure and internal motions of NGC 3242, NGC 6720 and NGC 7027. A technique is described which uses the velocity field to map variations in the electron temperature and density along the line of sight as well as across the face of the nebula. It is shown how a Fabry Perot may be used in conjunction with multi-element array detectors to facilitate this technique. Finally some extensions to the technique of capacitance micrometry are discussed which allow the operation of a single air-spaced etalon over a wide range of capacitor gaps

  4. Visualization Tools for Planetary Data

    Science.gov (United States)

    DeWolfe, Alexandria; Larsen, Kristopher; Brain, David; Chaffin, Michael; Harter, Bryan; Putnam, Brian

    2017-04-01

    We have developed a set of software tools for displaying and analyzing data from the MAVEN and MMS missions. In order to better visualize the science data and models, we have constructed 3D visualizations of MAVEN orbiting Mars and MMS orbiting Earth using the CesiumJS library. These visualizations allow viewing of not only spacecraft orientation and position over time, but also scientific data from the spacecraft, and atmospheric models as well. We have also developed a Python toolkit which replicates the functionality of the widely-used IDL "tplot" toolkit for analyzing planetary atmospheric data. We use the bokeh and matplotlib libraries to generate interactive line plots and spectrograms, providing additional functionality beyond the capabilities of IDL graphics. These Python tools are generalized to work with missions beyond MAVEN, and our open-source software is available on Github.

  5. Planetary accretion in circumstellar disks

    Science.gov (United States)

    Lissauer, Jack J.; Stewart, Glen R.

    1993-01-01

    The formation of terrestrial planets and the cores of Jovian planets is reviewed in the framework of the planetesimal hypothesis, wherein planets are assumed to grow via the pairwise accumulation of small solid bodies. Emphasis is placed on the dynamics of solid body accretion from kilometer size planetesimals to terrestrial type planets. This stage of planetary growth is least dependent on the characteristics of the evolutionary state of the central star. It is concluded that the evolution of the planetesimal size distribution is determined by the gravitationally enhanced collision cross-section, which favors collisions between planetesimals with smaller velocities. Runaway growth of the largest planetesimal in each accretion zone appears to be a likely outcome. The subsequent accumulation of the resulting protoplanets leads to a large degree of radial mixing in the terrestrial planet region, and giant impacts are probable.

  6. Sonic anemometry of planetary atmospheres

    Science.gov (United States)

    Cuerva, Alvaro; Sanz-Andrés, Angel; Lorenz, Ralph D.

    2004-02-01

    Sonic anemometers are robust, fast and reliable wind sensors which are able to measure the complete wind speed vector at high sampling rates. All these characteristics make sonic anemometers to be ideal candidates for atmospheric applications. Since sonic anemometers have not moving parts and they can be designed to have loss mass and power consumption, they have become adequate for planetary exploration purposes, both for atmosphere studies and for flying robot control. However, some challenges must be undertaken before implementing their use. Problems such as sound attenuation in different atmospheres, sensor/air acoustic impedance matching as well as flow/fluid dependence of sonic measurements have to be considered when these sensors are used in other atmospheres.

  7. A dynamic model to predict modulation sidebands of a planetary gear set having manufacturing errors

    Science.gov (United States)

    Inalpolat, Murat; Kahraman, Ahmet

    2010-02-01

    In this study, a nonlinear time-varying dynamic model is proposed to predict modulation sidebands of planetary gear sets. This discrete dynamic model includes periodically time-varying gear mesh stiffnesses and the nonlinearities associated with tooth separations. The model uses forms of gear mesh interface excitations that are amplitude and frequency modulated due to a class of gear manufacturing errors to predict dynamic forces at all sun-planet and ring-planet gear meshes. The predicted gear mesh force spectra are shown to exhibit well-defined modulation sidebands at frequencies associated with the rotational speeds of gears relative to the planet carrier. This model is further combined with a previously developed model that accounts for amplitude modulations due to rotation of the carrier to predict acceleration spectra at a fixed position in the planetary transmission housing. Individual contributions of each gear error in the form of amplitude and frequency modulations are illustrated through an example analysis. Comparisons are made to measured spectra to demonstrate the capability of the model in predicting the sidebands of a planetary gear set with gear manufacturing errors and a rotating carrier.

  8. The International Planetary Data Alliance

    Science.gov (United States)

    Stein, T.; Arviset, C.; Crichton, D. J.

    2017-12-01

    The International Planetary Data Alliance (IPDA) is an association of partners with the aim of improving the quality of planetary science data and services to the end users of space based instrumentation. The specific mission of the IPDA is to facilitate global access to, and exchange of, high quality scientific data products managed across international boundaries. Ensuring proper capture, accessibility and availability of the data is the task of the individual member space agencies. The IPDA was formed in 2006 with the purpose of adopting standards and developing collaborations across agencies to ensure data is captured in common formats. Member agencies include: Armenian Astronomical Society, China National Space Agency (CNSA), European Space Agency (ESA), German Aerospace Center (DLR), Indian Space Research Organization (ISRO), Italian Space Agency (ASI), Japanese Aerospace Exploration Agency (JAXA), National Air and Space Administration (NASA), National Centre for Space Studies (CNES), Space Research Institute (IKI), UAE Space Agency, and UK Space Agency. The IPDA Steering Committee oversees the execution of projects and coordinates international collaboration. The IPDA conducts a number of focused projects to enable interoperability, construction of compatible archives, and the operation of the IPDA as a whole. These projects have helped to establish the IPDA and to move the collaboration forward. A key project that is currently underway is the implementation of the PDS4 data standard. Given the international focus, it has been critical that the PDS and the IPDA collaborate on its development. Also, other projects have been conducted successfully, including developing the IPDA architecture and corresponding requirements, developing shared registries for data and tools across international boundaries, and common templates for supporting agreements for archiving and sharing data for international missions. Several projects demonstrating interoperability across

  9. Performance evaluation of a quasi-microscope for planetary landers

    Science.gov (United States)

    Burcher, E. E.; Huck, F. O.; Wall, S. D.; Woehrle, S. B.

    1977-01-01

    Spatial resolutions achieved with cameras on lunar and planetary landers have been limited to about 1 mm, whereas microscopes of the type proposed for such landers could have obtained resolutions of about 1 um but were never accepted because of their complexity and weight. The quasi-microscope evaluated in this paper could provide intermediate resolutions of about 10 um with relatively simple optics that would augment a camera, such as the Viking lander camera, without imposing special design requirements on the camera of limiting its field of view of the terrain. Images of natural particulate samples taken in black and white and in color show that grain size, shape, and texture are made visible for unconsolidated materials in a 50- to 500-um size range. Such information may provide broad outlines of planetary surface mineralogy and allow inferences to be made of grain origin and evolution. The mineralogical descriptions of single grains would be aided by the reflectance spectra that could, for example, be estimated from the six-channel multispectral data of the Viking lander camera.

  10. X-ray absorption spectra and emission spectra of plasmas

    International Nuclear Information System (INIS)

    Peng Yonglun; Yang Li; Wang Minsheng; Li Jiaming

    2002-01-01

    The author reports a theoretical method to calculate the resolved absorption spectra and emission spectra (optically thin) of hot dense plasmas. Due to its fully relativistic treatment incorporated with the quantum defect theory, it calculates the absorption spectra and emission spectra for single element or multi-element plasmas with little computational efforts. The calculated absorption spectra of LTE gold plasmas agree well with the experimental ones. It also calculates the optical thin emission spectra of LTE gold plasmas, which is helpful to diagnose the plasmas of relevant ICF plasmas. It can also provide the relevant parameters such as population density of various ionic stages, precise radiative properties for ICF studies

  11. An online planetary exploration tool: ;Country Movers;

    Science.gov (United States)

    Gede, Mátyás; Hargitai, Henrik

    2017-08-01

    Results in astrogeologic investigations are rarely communicated towards the general public by maps despite the new advances in planetary spatial informatics and new spatial datasets in high resolution and more complete coverage. Planetary maps are typically produced by astrogeologists for other professionals, and not by cartographers for the general public. We report on an application designed for students, which uses cartography as framework to aid the virtual exploration of other planets and moons, using the concepts of size comparison and travel time calculation. We also describe educational activities that build on geographic knowledge and expand it to planetary surfaces.

  12. Planetary climates (princeton primers in climate)

    CERN Document Server

    Ingersoll, Andrew

    2013-01-01

    This concise, sophisticated introduction to planetary climates explains the global physical and chemical processes that determine climate on any planet or major planetary satellite--from Mercury to Neptune and even large moons such as Saturn's Titan. Although the climates of other worlds are extremely diverse, the chemical and physical processes that shape their dynamics are the same. As this book makes clear, the better we can understand how various planetary climates formed and evolved, the better we can understand Earth's climate history and future.

  13. Resolving the Disk-Halo Degeneracy using Planetary Nebulae

    Science.gov (United States)

    Aniyan, S.; Freeman, K. C.; Arnaboldi, M.; Gerhard, O.; Coccato, L.; Fabricius, M.; Kuijken, K.; Merrifield, M.

    2017-10-01

    The decomposition of the 21 cm rotation curve of galaxies into contribution from the disk and dark halo depends on the adopted mass to light ratio (M/L) of the disk. Given the vertical velocity dispersion (σ z ) of stars in the disk and its scale height (h z ), the disk surface density and hence the M/L can be estimated. Earlier works have used this technique to conclude that galaxy disks are submaximal. Here we address an important conceptual problem: star-forming spirals have an old (kinematically hot) disk population and a young cold disk population. Both of these populations contribute to the integrated light spectra from which σ z is measured. The measured scale height h z is for the old disk population. In the Jeans equation, σ z and h z must pertain to the same population. We have developed techniques to extract the velocity dispersion of the old disk from integrated light spectra and from samples of planetary nebulae. We present the analysis of the disk kinematics of the galaxy NGC 628 using IFU data in the inner regions and planetary nebulae as tracers in the outer regions of the disk. We demonstrate that using the scale height of the old thin disk with the vertical velocity dispersion of the same population, traced by PNe, results in a maximal disk for NGC 628. Our analysis concludes that previous studies underestimate the disk surface mass density by ~ 2, sufficient to make a maximal disk for NGC 628 appear like a submaximal disk.

  14. Thermoluminescence spectra of amethyst

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Q. [Suzhou Railway Teachers College (China). Dept. of Physics; Yang, B. [Beijing Normal University (China). Dept. of Physics; Wood, R.A.; White, D.R.R.; Townsend, P.D.; Luff, B.J. [Sussex Univ., Brighton (United Kingdom). School of Mathematical and Physical Sciences

    1994-04-01

    Thermoluminescence and cathodoluminescence data from natural and synthetic amethyst and synthetic quartz samples are compared. The spectra include features from the quartz host lattice and from impurity-generated recombination sites. Emission features exist throughout the wavelength range studied, 250-800 nm. The near infrared emission at 740-750 nm appears to be characteristic of the amethyst and is proposed to be due to Fe ion impurity. (Author).

  15. Estimating Spectra from Photometry

    Science.gov (United States)

    Kalmbach, J. Bryce; Connolly, Andrew J.

    2017-12-01

    Measuring the physical properties of galaxies such as redshift frequently requires the use of spectral energy distributions (SEDs). SED template sets are, however, often small in number and cover limited portions of photometric color space. Here we present a new method to estimate SEDs as a function of color from a small training set of template SEDs. We first cover the mathematical background behind the technique before demonstrating our ability to reconstruct spectra based upon colors and then compare our results to other common interpolation and extrapolation methods. When the photometric filters and spectra overlap, we show that the error in the estimated spectra is reduced by more than 65% compared to the more commonly used techniques. We also show an expansion of the method to wavelengths beyond the range of the photometric filters. Finally, we demonstrate the usefulness of our technique by generating 50 additional SED templates from an original set of 10 and by applying the new set to photometric redshift estimation. We are able to reduce the photometric redshifts standard deviation by at least 22.0% and the outlier rejected bias by over 86.2% compared to original set for z ≤ 3.

  16. UNUSUAL DUST EMISSION FROM PLANETARY NEBULAE IN THE MAGELLANIC CLOUDS

    International Nuclear Information System (INIS)

    Bernard-Salas, J.; Sloan, G. C.; Gutenkunst, S.; Houck, J. R.; Peeters, E.; Matsuura, M.; Tielens, A. G. G. M.; Zijlstra, A. A.

    2009-01-01

    We present a Spitzer Space Telescope spectroscopic study of a sample of 25 planetary nebulae (PNe) in the Magellanic Clouds (MCs). The low-resolution modules are used to analyze the dust features present in the infrared spectra. This study complements a previous work by the same authors where the same sample was analyzed in terms of neon and sulfur abundances. Over half of the objects (14) show emission of polycyclic aromatic hydrocarbons, typical of carbon-rich dust environments. We compare the hydrocarbon emission in our objects to those of Galactic H II regions and PNe, and Large Magellanic Cloud/Small Magellanic Cloud H II regions. Amorphous silicates are seen in just two objects, enforcing the now well known fact that oxygen-rich dust is less common at low metallicities. Besides these common features, some PNe show very unusual dust. Nine objects show a strong silicon carbide feature at 11 μm and 12 of them show magnesium sulfide emission starting at 25 μm. The high percentage of spectra with silicon carbide in the MCs is not common. Two objects show a broadband which may be attributed to hydrogenated amorphous carbon and weak low-excitation atomic lines. It is likely that these nebulae are very young. The spectra of the remaining eight nebulae are dominated by the emission of fine-structure lines with a weak continuum due to thermal emission of dust, although in a few cases the signal-to-noise ratio in the spectra is low, and weak dust features may not have been detected.

  17. Extension of Einstein's Planetary Theory Based on Generalized ...

    African Journals Online (AJOL)

    In this article, the generalized Einstein's radial equation of motion in the equatorial plane of the Sun is transformed to obtain additional correction terms to all order of C2 to Einstein's planetary equation of motion and hence to the planetary parameters. Keywords: Radial Equation; Planetary Equation; Planetary parameters ...

  18. Planetary science: Haze cools Pluto's atmosphere

    Science.gov (United States)

    West, Robert A.

    2017-11-01

    Modelling suggests that Pluto's atmospheric temperature is regulated by haze, unlike the other planetary bodies in the Solar System. The finding has implications for our understanding of exoplanetary atmospheres. See Letter p.352

  19. Observatory for Planetary Investigations from the Stratosphere

    Data.gov (United States)

    National Aeronautics and Space Administration — The Observatory for Planetary Investigation from the Stratosphere (OPIS) project demonstrated the ability of the Wallops Arc Second Pointing (WASP) system to provide...

  20. Planetary Impacts by Clustered Quark Matter Strangelets

    OpenAIRE

    Labun, Lance; Rafelski, Jan

    2011-01-01

    We propose a model of clustered u-d-s quark matter that leads to stable bulk strange quark matter. We discuss qualitatively consequences of impacts by sub-planetary mass strangelets on rocky solar system bodies.

  1. Soft x-ray Planetary Imager

    Data.gov (United States)

    National Aeronautics and Space Administration — The project is to prototype a soft X-ray Imager for planetary applications that has the sensitivity to observe solar system sources of soft  X-ray emission. A strong...

  2. Subsurface Prospecting by Planetary Drones, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed program innovates subsurface prospecting by planetary drones to seek a solution to the difficulty of robotic prospecting, sample acquisition, and sample...

  3. Sonar equations for planetary exploration.

    Science.gov (United States)

    Ainslie, Michael A; Leighton, Timothy G

    2016-08-01

    The set of formulations commonly known as "the sonar equations" have for many decades been used to quantify the performance of sonar systems in terms of their ability to detect and localize objects submerged in seawater. The efficacy of the sonar equations, with individual terms evaluated in decibels, is well established in Earth's oceans. The sonar equations have been used in the past for missions to other planets and moons in the solar system, for which they are shown to be less suitable. While it would be preferable to undertake high-fidelity acoustical calculations to support planning, execution, and interpretation of acoustic data from planetary probes, to avoid possible errors for planned missions to such extraterrestrial bodies in future, doing so requires awareness of the pitfalls pointed out in this paper. There is a need to reexamine the assumptions, practices, and calibrations that work well for Earth to ensure that the sonar equations can be accurately applied in combination with the decibel to extraterrestrial scenarios. Examples are given for icy oceans such as exist on Europa and Ganymede, Titan's hydrocarbon lakes, and for the gaseous atmospheres of (for example) Jupiter and Venus.

  4. Electron densities in planetary nebulae

    International Nuclear Information System (INIS)

    Stanghellini, L.; Kaler, J.B.

    1989-01-01

    Electron densities for 146 planetary nebulae have been obtained for analyzing a large sample of forbidden lines by interpolating theoretical curves obtained from solutions of the five-level atoms using up-to-date collision strengths and transition probabilities. Electron temperatures were derived from forbidden N II and/or forbidden O III lines or were estimated from the He II 4686 A line strengths. The forbidden O II densities are generally lower than those from forbidden Cl III by an average factor of 0.65. For data sets in which forbidden O II and forbidden S II were observed in common, the forbidden O II values drop to 0.84 that of the forbidden S II, implying that the outermost parts of the nebulae might have elevated densities. The forbidden Cl II and forbidden Ar IV densities show the best correlation, especially where they have been obtained from common data sets. The data give results within 30 percent of one another, assuming homogeneous nebulae. 106 refs

  5. Galaxy dynamics with the Planetary Nebula Spectrograph

    OpenAIRE

    Napolitano, N. R.; Romanowsky, A. J.; Douglas, N. G.; Capaccioli, M.; Arnaboldi, M.; Kuijken, K.; Merrifield, M. R.; Freeman, K. C.; Gerhard, O.

    2004-01-01

    The Planetary Nebula Spectrograph is a dedicated instrument for measuring radial velocity of individual Planetary Nebulae (PNe) in galaxies. This new instrument is providing crucial data with which to probe the structure of dark halos in the outskirts of elliptical galaxies in particular, which are traditionally lacking of easy interpretable kinematical tracers at large distance from the center. Preliminary results on a sample of intermediate luminosity galaxies have shown little dark matter ...

  6. International Planetary Data Alliance (IPDA) Information Model

    Science.gov (United States)

    Hughes, John Steven; Beebe, R.; Guinness, E.; Heather, D.; Huang, M.; Kasaba, Y.; Osuna, P.; Rye, E.; Savorskiy, V.

    2007-01-01

    This document is the third deliverable of the International Planetary Data Alliance (IPDA) Archive Data Standards Requirements Identification project. The goal of the project is to identify a subset of the standards currently in use by NASAs Planetary Data System (PDS) that are appropriate for internationalization. As shown in the highlighted sections of Figure 1, the focus of this project is the Information Model component of the Data Architecture Standards, namely the object models, a data dictionary, and a set of data formats.

  7. Measuring Transmission Spectra from the Ground

    Science.gov (United States)

    Jordan, Andres; Espinoza, Nestor; Eyheramendy, Susana

    2015-08-01

    Transmission spectroscopy allows study of the atmospheres of exoplanets without the need of spatially resolving them from their parent stars and is one of the most valuable follow-up possibilities offered by transiting systems. The measurement of a transmission spectrum, i.e. the apparent planetary size in units in the stellar radius as a function of wavelength, is conceptually simple, but the expected features that need to be discerned are on the order of one part in a thousand or less, and need to be extracted against a background of (potentially correlated) noise and systematic effects with amplitudes greatly exceeding that of the sought signal. In this talk I will describe how we have tackled the estimation of transmission spectra in a ground based survey we are carrying out with IMACS at Las Campanas Observatory, the Arizona-CfA-Catolica Exoplanet Spectroscopy Survey. Our treatment assumes an additive model consisting of the signal, common systematics and one of a set of stochastic processes with different memory characteristics for the noise. Common systematics are estimated from comparison stars using principal component analysis and the model parameter posterior distributions are estimated using MCMC. Model comparison is used to let the data select the model with the most appropriate noise component. I will illustrate the performance of our approach, and discuss possible avenues of improvement. I will also illustrate the importance of potential biases arising from our incomplete knowledge of stellar properties. In particular, I will show that limb darkening assumptions can limit the accuracy of our estimates of planetary radii above the achievable precisions in regimes currently being probed.

  8. Deconvolution of Positrons' Lifetime spectra

    International Nuclear Information System (INIS)

    Calderin Hidalgo, L.; Ortega Villafuerte, Y.

    1996-01-01

    In this paper, we explain the iterative method previously develop for the deconvolution of Doppler broadening spectra using the mathematical optimization theory. Also, we start the adaptation and application of this method to the deconvolution of positrons' lifetime annihilation spectra

  9. Migration-induced architectures of planetary systems.

    Science.gov (United States)

    Szuszkiewicz, Ewa; Podlewska-Gaca, Edyta

    2012-06-01

    The recent increase in number of known multi-planet systems gives a unique opportunity to study the processes responsible for planetary formation and evolution. Special attention is given to the occurrence of mean-motion resonances, because they carry important information about the history of the planetary systems. At the early stages of the evolution, when planets are still embedded in a gaseous disc, the tidal interactions between the disc and planets cause the planetary orbital migration. The convergent differential migration of two planets embedded in a gaseous disc may result in the capture into a mean-motion resonance. The orbital migration taking place during the early phases of the planetary system formation may play an important role in shaping stable planetary configurations. An understanding of this stage of the evolution will provide insight on the most frequently formed architectures, which in turn are relevant for determining the planet habitability. The aim of this paper is to present the observational properties of these planetary systems which contain confirmed or suspected resonant configurations. A complete list of known systems with such configurations is given. This list will be kept by us updated from now on and it will be a valuable reference for studying the dynamics of extrasolar systems and testing theoretical predictions concerned with the origin and the evolution of planets, which are the most plausible places for existence and development of life.

  10. Automatic Feature Extraction from Planetary Images

    Science.gov (United States)

    Troglio, Giulia; Le Moigne, Jacqueline; Benediktsson, Jon A.; Moser, Gabriele; Serpico, Sebastiano B.

    2010-01-01

    With the launch of several planetary missions in the last decade, a large amount of planetary images has already been acquired and much more will be available for analysis in the coming years. The image data need to be analyzed, preferably by automatic processing techniques because of the huge amount of data. Although many automatic feature extraction methods have been proposed and utilized for Earth remote sensing images, these methods are not always applicable to planetary data that often present low contrast and uneven illumination characteristics. Different methods have already been presented for crater extraction from planetary images, but the detection of other types of planetary features has not been addressed yet. Here, we propose a new unsupervised method for the extraction of different features from the surface of the analyzed planet, based on the combination of several image processing techniques, including a watershed segmentation and the generalized Hough Transform. The method has many applications, among which image registration and can be applied to arbitrary planetary images.

  11. Nuclear Spectra from Skyrmions

    International Nuclear Information System (INIS)

    Manton, N.

    2009-01-01

    For some time now, the Skyrme model has been studied as an effective nonlinear field theory in nuclear physics. Its classical, stable soliton solutions, called Skyrmions, have a conserved topological charge which is identified with baryon number. A quantized Skyrmion models a nucleus. Skyrmions with baryon number a multiple of four are structurally similar to the cluster structures well-known in the a-particle model. The most convenient quantization scheme treats a Skyrmion as a rigid body in space and isospin space, and quantizes just the collective rotational motion. Some selected vibrational modes of Skyrmions may be included too. This approach has been applied previously to Skyrmions up to baryon number about 6, by Braaten and Carson, Kopeliovich, Walhout, and others. Recently, Battye, Manton, Sutcliffe and Wood have calculated the moment of inertia tensors in space and isospace for Skyrmions up to baryon number 12. The allowed spin and isospin states have been found, and the energy spectra calculated. These spectra agree quite well with experimental spectra of several light nuclei, including 6 L i, 8 B e, 1 2C , and their various isotopes. However, for this to work, the length scale needs to be set rather larger than the traditional value determined by Adkins and Nappi using the nucleon and delta resonance masses. The most interesting theoretical feature of these calculations is that isospin and spin excitations are treated in a uniform way. There are quite subtle constraints on the possible spin and isospin values, because of the classical symmetries of each Skyrmion. Manton and his students, and Battye and Sutcliffe, have published a number of papers on classical and quantized Skyrmions in journals and on the arXiv. They are also jointly contributing an invited chapter on Skyrmions and Nuclei to the book The Multifaceted Skyrmion, currently being edited by G. Brown and M. Rho.(author)

  12. Planetary Geologic Mapping Handbook - 2010. Appendix

    Science.gov (United States)

    Tanaka, K. L.; Skinner, J. A., Jr.; Hare, T. M.

    2010-01-01

    Geologic maps present, in an historical context, fundamental syntheses of interpretations of the materials, landforms, structures, and processes that characterize planetary surfaces and shallow subsurfaces. Such maps also provide a contextual framework for summarizing and evaluating thematic research for a given region or body. In planetary exploration, for example, geologic maps are used for specialized investigations such as targeting regions of interest for data collection and for characterizing sites for landed missions. Whereas most modern terrestrial geologic maps are constructed from regional views provided by remote sensing data and supplemented in detail by field-based observations and measurements, planetary maps have been largely based on analyses of orbital photography. For planetary bodies in particular, geologic maps commonly represent a snapshot of a surface, because they are based on available information at a time when new data are still being acquired. Thus the field of planetary geologic mapping has been evolving rapidly to embrace the use of new data and modern technology and to accommodate the growing needs of planetary exploration. Planetary geologic maps have been published by the U.S. Geological Survey (USGS) since 1962. Over this time, numerous maps of several planetary bodies have been prepared at a variety of scales and projections using the best available image and topographic bases. Early geologic map bases commonly consisted of hand-mosaicked photographs or airbrushed shaded-relief views and geologic linework was manually drafted using mylar bases and ink drafting pens. Map publishing required a tedious process of scribing, color peel-coat preparation, typesetting, and photo-laboratory work. Beginning in the 1990s, inexpensive computing, display capability and user-friendly illustration software allowed maps to be drawn using digital tools rather than pen and ink, and mylar bases became obsolete. Terrestrial geologic maps published by

  13. Dust Dynamics Near Planetary Surfaces

    Science.gov (United States)

    Colwell, Joshua; Hughes, Anna; Grund, Chris

    Observations of a lunar "horizon glow" by several Surveyor spacecraft in the 1960s opened the study of the dynamics of charged dust particles near planetary surfaces. The surfaces of the Moon and other airless planetary bodies in the solar system (asteroids, and other moons) are directly exposed to the solar wind and ionizing solar ultraviolet radiation, resulting in a time-dependent electric surface potential. Because these same objects are also exposed to bombardment by micrometeoroids, the surfaces are usually characterized by a power-law size distribution of dust that extends to sub-micron-sized particles. Individual particles can acquire a charge different from their surroundings leading to electrostatic levitation. Once levitated, particles may simply return to the surface on nearly ballistic trajectories, escape entirely from the moon or asteroid if the initial velocity is large, or in some cases be stably levitated for extended periods of time. All three outcomes have observable consequences. Furthermore, the behavior of charged dust near the surface has practical implications for planned future manned and unmanned activities on the lunar surface. Charged dust particles also act as sensitive probes of the near-surface plasma environment. Recent numerical modeling of dust levitation and transport show that charged micron-sized dust is likely to accumulate in topographic lows such as craters, providing a mechanism for the creation of dust "ponds" observed on the asteroid 433 Eros. Such deposition can occur when particles are supported by the photoelectron sheath above the dayside and drift over shadowed regions of craters where the surface potential is much smaller. Earlier studies of the lunar horizon glow are consistent with those particles being on simple ballistic trajectories following electrostatic launching from the surface. Smaller particles may be accelerated from the lunar surface to high altitudes consistent with observations of high altitude

  14. Seizmic response spectra

    Directory of Open Access Journals (Sweden)

    Igor Leššo

    2005-12-01

    Full Text Available A computation of 1D and 3D seismic motion parameters was made and the influence of input parameters on these parameters were analysed. A modelling was realised on the examples of sedimentary structures geotechnical models. This comparison provides different spectral and frequencial values and spectral accelerations. The differences in seismic response spectra are influenced not only by properties of geological structures but also by the methodics of the soil structure interaction modeling and input time history spectral composition. However, the influence of geotechnical properties of geological structures on the output results are apparent. The modelling results of different input time history spectral composition, the Ricker impuls and the Gabor function were compared. In the area of cement factory in Rohožník, the new rotary kiln furnance is planned to be build. In the sense of STN 73 0036 the expert seismic judgment has been claimed. The standard and local seismic response spectra is computed for the place where the rotary kiln will be situated. The application of the local spectral acceleration in seismic load computations enables to save costs in comparing with the standard acceleration.

  15. Geophysics of Small Planetary Bodies

    Science.gov (United States)

    Asphaug, Erik I.

    1998-01-01

    As a SETI Institute PI from 1996-1998, Erik Asphaug studied impact and tidal physics and other geophysical processes associated with small (low-gravity) planetary bodies. This work included: a numerical impact simulation linking basaltic achondrite meteorites to asteroid 4 Vesta (Asphaug 1997), which laid the groundwork for an ongoing study of Martian meteorite ejection; cratering and catastrophic evolution of small bodies (with implications for their internal structure; Asphaug et al. 1996); genesis of grooved and degraded terrains in response to impact; maturation of regolith (Asphaug et al. 1997a); and the variation of crater outcome with impact angle, speed, and target structure. Research of impacts into porous, layered and prefractured targets (Asphaug et al. 1997b, 1998a) showed how shape, rheology and structure dramatically affects sizes and velocities of ejecta, and the survivability and impact-modification of comets and asteroids (Asphaug et al. 1998a). As an affiliate of the Galileo SSI Team, the PI studied problems related to cratering, tectonics, and regolith evolution, including an estimate of the impactor flux around Jupiter and the effect of impact on local and regional tectonics (Asphaug et al. 1998b). Other research included tidal breakup modeling (Asphaug and Benz 1996; Schenk et al. 1996), which is leading to a general understanding of the role of tides in planetesimal evolution. As a Guest Computational Investigator for NASA's BPCC/ESS supercomputer testbed, helped graft SPH3D onto an existing tree code tuned for the massively parallel Cray T3E (Olson and Asphaug, in preparation), obtaining a factor xIO00 speedup in code execution time (on 512 cpus). Runs which once took months are now completed in hours.

  16. Cryogenic Reflectance Spectroscopy in Support of Planetary Missions

    Science.gov (United States)

    Dalton, J. B.

    2002-01-01

    Present understanding of planetary composition is based primarily on remotely-sensed data, and in particular upon ultraviolet, visible, and infrared spectroscopy. Spectra acquired by telescopic and spacecraft instruments are compared to laboratory measurements of pure materials in order to identify surface components based on characteristic absorption features. Cryogenic spectral measurements are necessary for the study of worlds beyond the Earth's orbit. While some materials exhibit only small spectral changes as a function of temperature, many others are strongly temperature-dependent. For example, hydrated salts exhibit different spectral behavior under conditions appropriate to Europa than at terrestrial temperatures. The icy satellites of the outer solar system contain significant quantities of volatile ices which do not even exist at standard temperature and pressure (STP). A comprehensive spectral database of ices and minerals covering a wide temperature range will have applications ranging from the study of comets and Kuiper Belt objects to outer planet satellites and the polar regions of Mars. Efforts are presently underway at NASA-Ames to develop capabilities which will contribute to such a database. As spacecraft instruments feature increasing spatial and spectral resolution, appropriate laboratory reference spectra become increasingly critical to accurate interpretation of the spacecraft data.

  17. AKARI/IRC NEAR-INFRARED SPECTRAL ATLAS OF GALACTIC PLANETARY NEBULAE

    Energy Technology Data Exchange (ETDEWEB)

    Ohsawa, Ryou [Institute of Astronomy, Graduate School of Science, The University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan); Onaka, Takashi; Sakon, Itsuki [Department of Astronomy, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Matsuura, Mikako [School of Physics and Astronomy, Cardiff University, Queen’s Buildings, 5 The Parade, Roath, Cardiff CF24 3AA (United Kingdom); Kaneda, Hidehiro, E-mail: ohsawa@ioa.s.u-tokyo.ac.jp [Division of Particle and Astrophysical Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602 (Japan)

    2016-04-15

    Near-infrared (2.5–5.0 μm) low-resolution (λ/Δλ ∼ 100) spectra of 72 Galactic planetary nebulae (PNe) were obtained with the Infrared Camera (IRC) in the post-helium phase. The IRC, equipped with a 1′ × 1′ window for spectroscopy of a point source, was capable of obtaining near-infrared spectra in a slit-less mode without any flux loss due to a slit. The spectra show emission features including hydrogen recombination lines and the 3.3–3.5 μm hydrocarbon features. The intensity and equivalent width of the emission features were measured by spectral fitting. We made a catalog providing unique information on the investigation of the near-infrared emission of PNe. In this paper, details of the observations and characteristics of the catalog are described.

  18. Turning Planetary Theory Upside Down

    Science.gov (United States)

    2010-04-01

    The discovery of nine new transiting exoplanets is announced today at the RAS National Astronomy Meeting (NAM2010). When these new results were combined with earlier observations of transiting exoplanets astronomers were surprised to find that six out of a larger sample of 27 were found to be orbiting in the opposite direction to the rotation of their host star - the exact reverse of what is seen in our own Solar System. The new discoveries provide an unexpected and serious challenge to current theories of planet formation. They also suggest that systems with exoplanets of the type known as hot Jupiters are unlikely to contain Earth-like planets. "This is a real bomb we are dropping into the field of exoplanets," says Amaury Triaud, a PhD student at the Geneva Observatory who, with Andrew Cameron and Didier Queloz, leads a major part of the observational campaign. Planets are thought to form in the disc of gas and dust encircling a young star. This proto-planetary disc rotates in the same direction as the star itself, and up to now it was expected that planets that form from the disc would all orbit in more or less the same plane, and that they would move along their orbits in the same direction as the star's rotation. This is the case for the planets in the Solar System. After the initial detection of the nine new exoplanets [1] with the Wide Angle Search for Planets (WASP, [2]), the team of astronomers used the HARPS spectrograph on the 3.6-metre ESO telescope at the La Silla observatory in Chile, along with data from the Swiss Euler telescope, also at La Silla, and data from other telescopes to confirm the discoveries and characterise the transiting exoplanets [3] found in both the new and older surveys. Surprisingly, when the team combined the new data with older observations they found that more than half of all the hot Jupiters [4] studied have orbits that are misaligned with the rotation axis of their parent stars. They even found that six exoplanets in this

  19. Continuum Fitting HST QSO Spectra

    Science.gov (United States)

    Tytler, David; Oliversen, Ronald J. (Technical Monitor)

    2002-01-01

    The Principal Component Analysis (PCA) method which we are using to fit and describe QSO spectra relies upon the fact that QSO continuum are generally very smooth and simple except for emission and absorption lines. To see this we need high signal-to-noise (S/N) spectra of QSOs at low redshift which have relatively few absorption lines in the Lyman-a forest. We need a large number of such spectra to use as the basis set for the PCA analysis which will find the set of principal component spectra which describe the QSO family as a whole. We have found that too few HST spectra have the required S/N and hence we need to supplement them with ground based spectra of QSOs at higher redshift. We have many such spectra and we have been working to make them suitable for this analysis. We have concentrated on this topic since 12/15/01.

  20. Abundances of planetary nebula NGC 5315

    NARCIS (Netherlands)

    Pottasch, [No Value; Beintema, DA; Salas, JB; Koornneef, J; Feibelman, WA

    2002-01-01

    The ISO and IUE spectra of the elliptical nebula NGC 5315 is presented. These spectra are combined with the spectra in the visual wavelength region to obtain a complete, extinction corrected, spectrum. The chemical composition of the nebulae is then calculated and compared to previous

  1. Planetary Protection Bioburden Analysis Program

    Science.gov (United States)

    Beaudet, Robert A.

    2013-01-01

    is programmed in Visual Basic for Applications for installation as a simple add-in for Microsoft Excel. The user is directed to a graphical user interface (GUI) that requires user inputs and provides solutions directly in Microsoft Excel workbooks. This work was done by Shannon Ryan of the USRA Lunar and Planetary Institute for Johnson Space Center. Further information is contained in a TSP (see page 1). MSC- 24582-1 Micrometeoroid and Orbital Debris (MMOD) Shield Ballistic Limit Analysis Program Lyndon B. Johnson Space Center, Houston, Texas Commercially, because it is so generic, Enigma can be used for almost any project that requires engineering visualization, model building, or animation. Models in Enigma can be exported to many other formats for use in other applications as well. Educationally, Enigma is being used to allow university students to visualize robotic algorithms in a simulation mode before using them with actual hardware. This work was done by David Shores and Sharon P. Goza of Johnson Space Center; Cheyenne McKeegan, Rick Easley, Janet Way, and Shonn Everett of MEI Technologies; Mark Manning of PTI; and Mark Guerra, Ray Kraesig, and William Leu of Tietronix Software, Inc. For further information, contact the JSC Innovation Partnerships Office at (281) 483-3809. MSC-24211-1 Spitzer Telemetry Processing System NASA's Jet Propulsion Laboratory, Pasadena, California The Spitzer Telemetry Processing System (SirtfTlmProc) was designed to address objectives of JPL's Multi-mission Image Processing Lab (MIPL) in processing spacecraft telemetry and distributing the resulting data to the science community. To minimize costs and maximize operability, the software design focused on automated error recovery, performance, and information management. The system processes telemetry from the Spitzer spacecraft and delivers Level 0 products to the Spitzer Science Center. SirtfTlmProc is a unique system with automated error notification and recovery, with a real

  2. Planetary life: why and how?

    Science.gov (United States)

    Pratt, Andy; Kerr, William

    2012-07-01

    Understanding life in an astrobiological context requires that we understand why and how life emerged on earth. We report on the elaboration and preliminary testing of our recent model for the origin of life (Pratt, 2011). This model identifies key components, including availability of chemicals and geochemical energy sources, required for the emergence of planetary life. The model is based on the theory (Russell and Kanik, 2010) that life emerged as a mechanism for the dissipation of the intrinsic geochemical energy gradient of the planet. It proposes that life is founded on an ongoing chemical energy flux that can be harnessed more efficiently by autocatalytic networks of reactions than by direct chemical processes. Feedback and selection mechanisms are required to foster the apparently irreducible complexity found in cells. We posit that selective solubilisation in a hydrothermal flow system was a key mechanism that underpinned the emergence of life. Amongst other things, earthly cells are dependent on a combination of organic molecules, iron (for electron-transfer and catalysis) and phosphate (e.g. for digital information). Soluble aqueous systems that include all these components are constrained by precipitation chemistry (de Zwart et al., 2004). We propose that in situ abiological carbon fixation produced organic molecules that, in turn, led to more active carbon fixation catalysts and hence more efficient reduction of carbon oxides. By encapsulating free iron ions, these organic molecules also facilitated the solubilisation of phosphate species which thereby became integrated within this expanding autocatalytic network. We have evaluated the competitive solubility of phosphate species in the presence of iron and organic moieties to test this theory and provide evidence that this could act as positive feedback loop for a form of prebiological evolution that underpinned the emergence of complex cells. References, Pratt, A. J. (2011) Prebiological Evolution and

  3. Engaging Audiences in Planetary Science Through Visualizations

    Science.gov (United States)

    Shupla, C. B.; Mason, T.; Peticolas, L. M.; Hauck, K.

    2017-12-01

    One way to share compelling stories is through visuals. The Lunar and Planetary Institute (LPI), in collaboration with Laboratory for Atmospheric and Space Physics (LASP) and Space Science Laboratory at the University of California, Berkeley, has been working with planetary scientists to reach and engage audiences in their research through the use of visualizations. We will share how images and animations have been used in multiple mediums, including the planetarium, Science on a Sphere, the hyperwall, and within apps. Our objectives are to provide a tool that planetary scientists can use to tell their stories, as well as to increase audience awareness of and interest in planetary science. While scientists are involved in the selection of topics and the development of the visuals, LPI and partners seek to increase the planetary science community's awareness of these resources and their ability to incorporate them into their own public engagement efforts. This presentation will share our own resources and efforts, as well as the input received from scientists on how education and public engagement teams can best assist them in developing and using these resources, and disseminating them to both scientists and to informal science education venues.

  4. Access to the Online Planetary Research Literature

    Science.gov (United States)

    Henneken, E. A.; Accomazzi, A.; Kurtz, M. J.; Grant, C. S.; Thompson, D.; Di Milia, G.; Bohlen, E.; Murray, S. S.

    2009-12-01

    The SAO/NASA Astrophysics Data System (ADS) provides various free services for finding, accessing, and managing bibliographic data, including a basic search form, the myADS notification service, and private library capabilities (a useful tool for building bibliographies), plus access to scanned pages of published articles. The ADS also provides powerful search capabilities, allowing users to find e.g. the most instructive or most important articles on a given subject . For the Planetary Sciences, the citation statistics of the ADS have improved considerably with the inclusion of the references from Elsevier journals, including Icarus, Planetary and Space Science, and Earth and Planetary Science Letters. We currently have about 78 journals convering the planetary and space sciences (Advances in Space Research, Icarus, Solar Physics, Astrophusics and Space Science, JGRE, Meteoritics, to name a few). Currently, this set of journals represents about 180,000 articles and 1.1 million references. Penetration into the Solar Physics, Planetary Sciences and Geophysics community has increased significantly. During the period 2004-2008, user access to JGR and Icarus increased by a factor of 4.4, while e.g. access to the Astrophysical Journal "only" increased by a factor of 1.8.

  5. Fourier transform spectroscopy for future planetary missions

    Science.gov (United States)

    Brasunas, John C.; Hewagama, Tilak; Kolasinski, John R.; Kostiuk, Theodor

    2015-11-01

    Thermal-emission infrared spectroscopy is a powerful tool for exploring the composition, temperature structure, and dynamics of planetary atmospheres; and the temperature of solid surfaces. A host of Fourier transform spectrometers (FTS) such as Mariner IRIS, Voyager IRIS, and Cassini CIRS from NASA Goddard have made and continue to make important new discoveries throughout the solar system.Future FTS instruments will have to be more sensitive (when we concentrate on the colder, outer reaches of the solar system), and less massive and less power-hungry as we cope with decreasing resource allotments for future planetary science instruments. With this in mind, NASA Goddard was funded via the Planetary Instrument Definition and Development Progrem (PIDDP) to develop CIRS-lite, a smaller version of the CIRS FTS for future planetary missions. Following the initial validation of CIRS-lite operation in the laboratory, we have been acquiring atmospheric data in the 8-12 micron window at the 1.2 m telescope at the Goddard Geophysical and Astronomical Observatory (GGAO) in Greenbelt, MD. Targets so far have included Earth's atmosphere (in emission, and in absorption against the moon), and Venus.We will present the roadmap for making CIRS-lite a viable candidate for future planetary missions.

  6. X-ray observations of planetary nebulae

    International Nuclear Information System (INIS)

    Apparao, K.M.V.; Tarafdar, S.P.

    1990-01-01

    The Einstein satellite was used to observe 19 planetary nebulae and X-ray emission was detected from four planetary nebulae. The EXOSAT satellite observed 12 planetary nebulae and five new sources were detected. An Einstein HRI observation shows that NGC 246 is a point source, implying that the X-rays are from the central star. Most of the detected planetary nebulae are old and the X-rays are observed during the later stage of planetary nebulae/central star evolution, when the nebula has dispersed sufficiently and/or when the central star gets old and the heavy elements in the atmosphere settle down due to gravitation. However in two cases where the central star is sufficiently luminous X-rays were observed, even though they were young nebulae; the X-radiation ionizes the nebula to a degree, to allow negligible absorption in the nebula. Temperature T x is obtained using X-ray flux and optical magnitude and assuming the spectrum is blackbody. T x agrees with Zanstra temperature obtained from optical Helium lines. (author)

  7. The Role of NASA's Planetary Data System in the Planetary Spatial Data Infrastructure Initiative

    Science.gov (United States)

    Arvidson, R. E.; Gaddis, L. R.

    2017-12-01

    An effort underway in NASA's planetary science community is the Mapping and Planetary Spatial Infrastructure Team (MAPSIT, http://www.lpi.usra.edu/mapsit/). MAPSIT is a community assessment group organized to address a lack of strategic spatial data planning for space science and exploration. Working with MAPSIT, a new initiative of NASA and USGS is the development of a Planetary Spatial Data Infrastructure (PSDI) that builds on extensive knowledge on storing, accessing, and working with terrestrial spatial data. PSDI is a knowledge and technology framework that enables the efficient discovery, access, and exploitation of planetary spatial data to facilitate data analysis, knowledge synthesis, and decision-making. NASA's Planetary Data System (PDS) archives >1.2 petabytes of digital data resulting from decades of planetary exploration and research. The PDS charter focuses on the efficient collection, archiving, and accessibility of these data. The PDS emphasis on data preservation and archiving is complementary to that of the PSDI initiative because the latter utilizes and extends available data to address user needs in the areas of emerging technologies, rapid development of tailored delivery systems, and development of online collaborative research environments. The PDS plays an essential PSDI role because it provides expertise to help NASA missions and other data providers to organize and document their planetary data, to collect and maintain the archives with complete, well-documented and peer-reviewed planetary data, to make planetary data accessible by providing online data delivery tools and search services, and ultimately to ensure the long-term preservation and usability of planetary data. The current PDS4 information model extends and expands PDS metadata and relationships between and among elements of the collections. The PDS supports data delivery through several node services, including the Planetary Image Atlas (https

  8. Obtaining and Using Planetary Spatial Data into the Future: The Role of the Mapping and Planetary Spatial Infrastructure Team (MAPSIT)

    Science.gov (United States)

    Radebaugh, J.; Thomson, B. J.; Archinal, B.; Hagerty, J.; Gaddis, L.; Lawrence, S. J.; Sutton, S.

    2017-01-01

    Planetary spatial data, which include any remote sensing data or derived products with sufficient positional information such that they can be projected onto a planetary body, continue to rapidly increase in volume and complexity. These data are the hard-earned fruits of decades of planetary exploration, and are the end result of mission planning and execution. Maintaining these data using accessible formats and standards for all scientists has been necessary for the success of past, present, and future planetary missions. The Mapping and Planetary Spatial Infrastructure Team (MAPSIT) is a group of planetary community members tasked by NASA Headquarters to work with the planetary science community to identify and prioritize their planetary spatial data needs to help determine the best pathways for new data acquisition, usable product derivation, and tools/capability development that supports NASA's planetary science missions.

  9. 8-13 μm spectral observations of eight moderately extended planetary nebulae

    International Nuclear Information System (INIS)

    Roche, P.F.; Aitken, D.K.; Whitmore, B.

    1983-01-01

    8-13 μm spectra of eight moderately extended planetary nebulae have been obtained at a resolution of 0.24 μm using a 20-arcsec circular aperture. More compact planetaries which have been studied in this way generally show a strong continuum due to emission from dust, together with fine structure line emission. In contrast, these more extended objects have very weak continuum emission, and are dominated by fine structure line emission, especially by [S IV] which in several cases accounts for most of the broad-band 10 μm flux. There appears to be very little warm (>approx.= to 150 K) dust in some of these objects. (author)

  10. Greenhouse effect in planetary atmospheres caused by molecular symmetry breaking in intermolecular interactions

    Science.gov (United States)

    Vigasin, A. A.; Mokhov, I. I.

    2017-03-01

    It is believed that the greenhouse effect is related to the parameters of absorption spectra of polyatomic molecules, usually trace gases, in planetary atmospheres. The main components of all known atmospheres of celestial bodies are symmetrical molecules that do not possess the dipole-allowed purely rotational (and in the case of diatomic molecules, vibrational-rotational) absorption spectrum. Upon increased pressure, a weak absorption appears, induced by intermolecular interaction, which can lead to a greenhouse effect. The contribution of the induced absorption in radiative forcing of a dense atmosphere may amount to a few or even tens of W/m2. In conditions typical for the atmospheres of terrestrial planets (including paleoatmospheres), the collision-induced absorption and associated greenhouse effect may lead to an increase in surface temperature above the freezing point of water. There is a correlation between the temperature of an atmosphere and the intermolecular bonding energy of gases that dominate in planetary atmospheres of the Solar System.

  11. Planetary Nebulae Beyond the Milky Way

    CERN Document Server

    Stanghellini, L; Douglas, N. G; Proceedings of the ESO Workshop held at Garching, Germany, 19-21 May, 2004

    2006-01-01

    In the last decade extra-galactic planetary nebulae (PNe) have gained increasing importance. Improved observational capabilities have allowed fainter and fainter PNe to be studied in galaxies well beyond the Milky Way. Planetary nebulae can be detected to at least 30Mpc. They are found in galaxies of all types and also between the galaxies in nearby galaxy clusters. They are valuable as probes, both for providing the velocity of their host stars and also the evolutionary status and relation to the stellar population from which they formed. This book contains the proceedings of a workshop held at ESO headquarters in Garching in 2004, the first meeting devoted entirely to Extra-galactic Planetary Nebulae. A wide range of topics is covered, from stellar and nebular astrophysics to galactic dynamics and galaxy clusters, making this volume a unique and timely reference of broad astrophysical interest.

  12. Energy Balance Models and Planetary Dynamics

    Science.gov (United States)

    Domagal-Goldman, Shawn

    2012-01-01

    We know that planetary dynamics can have a significant affect on the climate of planets. Planetary dynamics dominate the glacial-interglacial periods on Earth, leaving a significant imprint on the geological record. They have also been demonstrated to have a driving influence on the climates of other planets in our solar system. We should therefore expect th.ere to be similar relationships on extrasolar planets. Here we describe a simple energy balance model that can predict the growth and thickness of glaciers, and their feedbacks on climate. We will also describe model changes that we have made to include planetary dynamics effects. This is the model we will use at the start of our collaboration to handle the influence of dynamics on climate.

  13. Planetary ring systems properties, structures, and evolution

    CERN Document Server

    Murray, Carl D

    2018-01-01

    Planetary rings are among the most intriguing structures of our solar system and have fascinated generations of astronomers. Collating emerging knowledge in the field, this volume reviews our current understanding of ring systems with reference to the rings of Saturn, Uranus, Neptune, and more. Written by leading experts, the history of ring research and the basics of ring–particle orbits is followed by a review of the known planetary ring systems. All aspects of ring system science are described in detail, including specific dynamical processes, types of structures, thermal properties and their origins, and investigations using computer simulations and laboratory experiments. The concluding chapters discuss the prospects of future missions to planetary rings, the ways in which ring science informs and is informed by the study of other astrophysical disks, and a perspective on the field's future. Researchers of all levels will benefit from this thorough and engaging presentation.

  14. Miniaturisation of imaging spectrometer for planetary exploration

    Science.gov (United States)

    Drossart, Pierre; Sémery, Alain; Réess, Jean-Michel; Combes, Michel

    2017-11-01

    Future planetary exploration on telluric or giant planets will need a new kind of instrumentation combining imaging and spectroscopy at high spectral resolution to achieve new scientific measurements, in particular for atmospheric studies in nadir configuration. We present here a study of a Fourier Transform heterodyne spectrometer, which can achieve these objectives, in the visible or infrared. The system is composed of a Michelson interferometer, whose mirrors have been replaced by gratings, a configuration studied in the early days of Fourier Transform spectroscopy, but only recently reused for space instrumentation, with the availability of large infrared mosaics. A complete study of an instrument is underway, with optical and electronic tests, as well as data processing analysis. This instrument will be proposed for future planetary missions, including ESA/Bepi Colombo Mercury Planetary Orbiter or Earth orbiting platforms.

  15. Design energy spectra for Turkey

    OpenAIRE

    López Almansa, Francisco; Yazgan, Ahmet Utku; Benavent Climent, Amadeo

    2012-01-01

    This work proposes design energy spectra in terms of velocity, derived through linear dynamic analyses on Turkish registers and intended for regions with design peak acceleration 0.3 g or higher. In the long and mid period ranges the analyses are linear, taking profit of the rather insensitivity of the spectra to the structural parameters other than the fundamental period; in the short period range, the spectra are more sensitive to the structural parameters and nonlinear analyses would be re...

  16. Tips and Tools for Teaching Planetary Science

    Science.gov (United States)

    Schneider, N. M.

    2011-10-01

    The poster will describe handson exercises with demonstrations, clicker questions and discussion to demonstrate how to help students understand planets on a deeper conceptual level. We'll also discuss ways to take the latest discoveries beyond "wow" and turn them into teachable moments. The goal is to give modern strategies for teaching planetary science, emphasizing physical concepts and comparative principles. All will be given digital copies of video clips, demonstration descriptions, clicker questions, web links and powerpoint slidesets on recent planetary science discoveries.

  17. Planetary nebulae and the interstellar magnetic field

    International Nuclear Information System (INIS)

    Heiligman, G.M.

    1980-01-01

    Previous workers have found a statistical correlation between the projected directions of the interstellar magnetic field and the major axes of planetary nebulae. This result has been examined theoretically using a numerical hydromagnetic model of a cold plasma nebula expanding into a uniform vacuum magnetic field, with nebular gas accreting on the surface. It is found that magnetic pressure alone is probably not sufficient to shape most planetary nebulae to the observed degree. Phenomena are discussed which could amplify simple magnetic pressure, alter nebular morphology and account for the observed correlation. (author)

  18. Mission Implementation Constraints on Planetary Muon Radiography

    Science.gov (United States)

    Jones, Cathleen E.; Kedar, Sharon; Naudet, Charles; Webb, Frank

    2011-01-01

    Cost: Use heritage hardware, especially use a tested landing system to reduce cost (Phoenix or MSL EDL stage). The sky crane technology delivers higher mass to the surface and enables reaching targets at higher elevation, but at a higher mission cost. Rover vs. Stationary Lander: Rover-mounted instrument enables tomography, but the increased weight of the rover reduces the allowable payload weight. Mass is the critical design constraint for an instrument for a planetary mission. Many factors that are minor factors or do not enter into design considerations for terrestrial operation are important for a planetary application. (Landing site, diurnal temperature variation, instrument portability, shock/vibration)

  19. Technology for NASA's Planetary Science Vision 2050.

    Science.gov (United States)

    Lakew, B.; Amato, D.; Freeman, A.; Falker, J.; Turtle, Elizabeth; Green, J.; Mackwell, S.; Daou, D.

    2017-01-01

    NASAs Planetary Science Division (PSD) initiated and sponsored a very successful community Workshop held from Feb. 27 to Mar. 1, 2017 at NASA Headquarters. The purpose of the Workshop was to develop a vision of planetary science research and exploration for the next three decades until 2050. This abstract summarizes some of the salient technology needs discussed during the three-day workshop and at a technology panel on the final day. It is not meant to be a final report on technology to achieve the science vision for 2050.

  20. Sequencing BPS spectra

    Energy Technology Data Exchange (ETDEWEB)

    Gukov, Sergei [Walter Burke Institute for Theoretical Physics, California Institute of Technology,1200 E California Blvd, Pasadena, CA 91125 (United States); Max-Planck-Institut für Mathematik,Vivatsgasse 7, D-53111 Bonn (Germany); Nawata, Satoshi [Walter Burke Institute for Theoretical Physics, California Institute of Technology,1200 E California Blvd, Pasadena, CA 91125 (United States); Centre for Quantum Geometry of Moduli Spaces, University of Aarhus,Nordre Ringgade 1, DK-8000 (Denmark); Saberi, Ingmar [Walter Burke Institute for Theoretical Physics, California Institute of Technology,1200 E California Blvd, Pasadena, CA 91125 (United States); Stošić, Marko [CAMGSD, Departamento de Matemática, Instituto Superior Técnico,Av. Rovisco Pais, 1049-001 Lisbon (Portugal); Mathematical Institute SANU,Knez Mihajlova 36, 11000 Belgrade (Serbia); Sułkowski, Piotr [Walter Burke Institute for Theoretical Physics, California Institute of Technology,1200 E California Blvd, Pasadena, CA 91125 (United States); Faculty of Physics, University of Warsaw,ul. Pasteura 5, 02-093 Warsaw (Poland)

    2016-03-02

    This paper provides both a detailed study of color-dependence of link homologies, as realized in physics as certain spaces of BPS states, and a broad study of the behavior of BPS states in general. We consider how the spectrum of BPS states varies as continuous parameters of a theory are perturbed. This question can be posed in a wide variety of physical contexts, and we answer it by proposing that the relationship between unperturbed and perturbed BPS spectra is described by a spectral sequence. These general considerations unify previous applications of spectral sequence techniques to physics, and explain from a physical standpoint the appearance of many spectral sequences relating various link homology theories to one another. We also study structural properties of colored HOMFLY homology for links and evaluate Poincaré polynomials in numerous examples. Among these structural properties is a novel “sliding” property, which can be explained by using (refined) modular S-matrix. This leads to the identification of modular transformations in Chern-Simons theory and 3d N=2 theory via the 3d/3d correspondence. Lastly, we introduce the notion of associated varieties as classical limits of recursion relations of colored superpolynomials of links, and study their properties.

  1. Using Gaussian Processes to Construct Flexible Models of Stellar Spectra

    Science.gov (United States)

    Czekala, Ian

    2018-01-01

    The use of spectra is fundamental to astrophysical fields ranging from exoplanets to stars to galaxies. In spite of this ubiquity, or perhaps because of it, there are a plethora of use cases that do not yet have physics-based forward models that can fit high signal-to-noise data to within the observational noise. These inadequacies result in subtle but systematic residuals not captured by any model, which complicates and biases parameter inference. Fortunately, the now-prevalent collection and archiving of large spectral datasets also provides an opening for empirical, data-driven approaches. We introduce one example of a time-series dataset of high-resolution stellar spectra, as is commonly delivered by planet-search radial velocity instruments like TRES, HIRES, and HARPS. Measurements of radial velocity variations of stars and their companions are essential for stellar and exoplanetary study; these measurements provide access to the fundamental physical properties that dictate all phases of stellar evolution and facilitate the quantitative study of planetary systems. In observations of a (spatially unresolved) spectroscopic binary star, one only ever records the composite sum of the spectra from the primary and secondary stars, complicating photospheric analysis of each individual star. Our technique “disentangles” the composite spectra by treating each underlying stellar spectrum as a Gaussian process, whose posterior predictive distribution is inferred simultaneously with the orbital parameters. To demonstrate the potential of this technique, we deploy it on red-optical time-series spectra of the mid-M-dwarf eclipsing binary LP661-13, which was recently discovered by the MEarth project. We successfully reconstruct the primary and secondary stellar spectra and report orbital parameters with improved precision compared to traditional radial velocity analysis techniques.

  2. The Planetary Science Archive (PSA): Exploration and discovery of scientific datasets from ESA's planetary missions

    Science.gov (United States)

    Vallat, C.; Besse, S.; Barbarisi, I.; Arviset, C.; De Marchi, G.; Barthelemy, M.; Coia, D.; Costa, M.; Docasal, R.; Fraga, D.; Heather, D. J.; Lim, T.; Macfarlane, A.; Martinez, S.; Rios, C.; Vallejo, F.; Said, J.

    2017-09-01

    The Planetary Science Archive (PSA) is the European Space Agency's (ESA) repository of science data from all planetary science and exploration missions. The PSA provides access to scientific datasets through various interfaces at http://psa.esa.int. All datasets are scientifically peer-reviewed by independent scientists, and are compliant with the Planetary Data System (PDS) standards. The PSA has started to implement a number of significant improvements, mostly driven by the evolution of the PDS standards, and the growing need for better interfaces and advanced applications to support science exploitation.

  3. SMALL PLANETARY SATELLITE COLORS V1.0

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set is intended to include published colors of small planetary satellites published up through December 2003. Small planetary satellites are defined as all...

  4. Abundance determinations in HII regions and planetary nebulae

    OpenAIRE

    Stasinska, Grazyna

    2002-01-01

    The methods of abundance determinations in HII regions and planetary nebulae are described, with emphasis on the underlying assumptions and inherent problems. Recent results on abundances in Galactic HII regions and in Galactic and extragalactic Planetary Nebulae are reviewed.

  5. Planetary Protection Technology Definition Team: Tasks, Status, and Feedback

    Science.gov (United States)

    Meyer, M. A.; Rummel, J. D.

    2016-10-01

    A Planetary Protection and Technology Definition Team will assess challenges to meeting planetary protection requirements to instruments and will suggest technological solutions. Status and initial findings will be reported.

  6. Spectropolarimeter for planetary exploration (SPEX) : Performance measurements with a prototype

    NARCIS (Netherlands)

    Voors, R.; Moon, S.G.; Hannemann, S.; Rietjens, J.H.H.; Harten, G. van; Snik, F.; Smit, M.; Stam, D.M.; Keller, C.U.; Laan, E.C.; Verlaan, A.L.; Vliegenthart, W.A.; Horst, R. ter; Navarro, R.; Wielinga, K.

    2011-01-01

    SPEX (Spectropolarimeter for Planetary Exploration) was developed in close cooperation between scientific institutes and space technological industries in the Netherlands. It is used for measuring microphysical properties of aerosols and cloud particles in planetary atmospheres. SPEX utilizes a

  7. 77 FR 20851 - NASA Advisory Council; Science Committee; Planetary Protection Subcommittee; Meeting

    Science.gov (United States)

    2012-04-06

    ... Needs for Planetary Protection --Planetary Protection for Icy Bodies in the Solar System --Current... SPACE ADMINISTRATION NASA Advisory Council; Science Committee; Planetary Protection Subcommittee... and Space Administration (NASA) announces a meeting of the Planetary Protection Subcommittee of the...

  8. Planetary protection in the framework of the Aurora exploration program

    Science.gov (United States)

    Kminek, G.

    The Aurora Exploration Program will give ESA new responsibilities in the field of planetary protection. Until now, ESA had only limited exposure to planetary protection from its own missions. With the proposed ExoMars and MSR missions, however, ESA will enter the realm of the highest planetary protection categories. As a consequence, the Aurora Exploration Program has initiated a number of activities in the field of planetary protection. The first and most important step was to establish a Planetary Protection Working Group (PPWG) that is advising the Exploration Program Advisory Committee (EPAC) on all matters concerning planetary protection. The main task of the PPWG is to provide recommendations regarding: Planetary protection for robotic missions to Mars; Planetary protection for a potential human mission to Mars; Review/evaluate standards & procedures for planetary protection; Identify research needs in the field of planetary protection. As a result of the PPWG deliberations, a number of activities have been initiated: Evaluation of the Microbial Diversity in SC Facilities; Working paper on legal issues of planetary protection and astrobiology; Feasibility study on a Mars Sample Return Containment Facility; Research activities on sterilization procedures; Training course on planetary protection (May, 2004); Workshop on sterilization techniques (fall 2004). In parallel to the PPWG, the Aurora Exploration Program has established an Ethical Working Group (EWG). This working group will address ethical issues related to astrobiology, planetary protection, and manned interplanetary missions. The recommendations of the working groups and the results of the R&D activities form the basis for defining planetary protection specification for Aurora mission studies, and for proposing modification and new inputs to the COSPAR planetary protection policy. Close cooperation and free exchange of relevant information with the NASA planetary protection program is strongly

  9. Transiting planetary system WASP-17 (Southworth+, 2012)

    DEFF Research Database (Denmark)

    Southworth, J.; Hinse, T. C.; Dominik, M.

    2013-01-01

    A light curve of four transits of the extrasolar planetary system WASP-17 is presented. The data were obtained using the Danish 1.5m telescope and DFOSC camera at ESO La Silla in 2012, with substantial telescope defocussing in order to improve the photometric precision of the observations. A Cous...

  10. Keplerian planetary orbits in multidimensional Euclidian spaces ...

    African Journals Online (AJOL)

    Newton's laws of motion are three physical laws that together, laid the foundation for classical three dimensional mechanics. They describe the relationship between a body and the forces acting upon it, and its motion in response to those forces. Kepler's laws of planetary motion are also three scientific laws describing the ...

  11. Detection of transient events on planetary bodies .

    Science.gov (United States)

    Di Martino, M.; Carbognani, A.

    Transient phenomena on planetary bodies are defined as luminous events of different intensities, which occur in planetary atmospheres and surfaces, their duration spans from about 0.1 s to some hours. They consist of meteors, bolides, lightning, impact flashes on solid surfaces, auroras, etc. So far, the study of these phenomena has been very limited, due to the lack of an ad hoc instrumentation, and their detection has been performed mainly on a serendipitous basis. Recently, ESA has issued an announcement of opportunity for the development of systems devoted to the detection of transient events in the Earth atmosphere and/or on the dark side of other planetary objects. One of such a detector as been designed and a prototype (\\textit{Smart Panoramic Optical Sensor Head}, SPOSH) has been constructed at Galileo Avionica S.p.A (Florence, Italy). For sake of clarity, in what follows, we classify the transient phenomena in ``Earth phenomena'' and ``Planetary phenomena'', even though some of them originate in a similar physical context.

  12. Equations Governing Kepler's Laws of Planetary Motion

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 14; Issue 12. Equations Governing Kepler's Laws of Planetary Motion. Renuka Ravindran. General Article Volume 14 Issue 12 December 2009 pp 1166-1170. Fulltext. Click here to view fulltext PDF. Permanent link:

  13. 1. Why Planetary Orbits are Closed

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 8; Issue 12. Planetary Orbits as Simple Harmonic Motion. Bikram Phookun. Classroom Volume 8 Issue 12 December 2003 pp 83-91. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/008/12/0083-0091 ...

  14. Planetary boundaries : Governing emerging risks and opportunities

    NARCIS (Netherlands)

    Galaz, V.; de Zeeuw, Aart; Shiroyama, Hideaki; Tripley, Debbie

    The climate, ecosystems and species, ozone layer, acidity of the oceans, the flow of energy and elements through nature, landscape change, freshwater systems, aerosols, and toxins—these constitute the planetary boundaries within which humanity must find a safe way to live and prosper. These are

  15. Hypersonic and planetary entry flight mechanics

    Science.gov (United States)

    Vinh, N. X.; Busemann, A.; Culp, R. D.

    1980-01-01

    The book treats hypersonic flight trajectories and atmospheric entry flight mechanics in light of their importance for space shuttle entry. Following a review of the structures of planetary atmospheres and aerodynamic forces, equations are derived for flight over a spherical planet, and the performance of long-range hypervelocity vehicles in extra-atmospheric flight is analyzed. Consideration is then given to vehicle trajectories in the powered and atmospheric reentry phases of flight, and several first-order solutions are derived for various planetary entry situations. The second-order theory of Loh for entry trajectories is presented along with the classical theories of Yaroshevskii and Chapman for entry into planetary atmospheres, and the thermal problems encountered in hypersonic flight are analyzed. A unified theory for entry into planetary atmospheres is then introduced which allows the performance of a general type of lifting vehicle to be studied, and applied to the analysis of orbit contraction due to atmospheric drag, flight with lift modulation and lateral maneuvers.

  16. Reconfigurable Autonomy for Future Planetary Rovers

    Science.gov (United States)

    Burroughes, Guy

    Extra-terrestrial Planetary rover systems are uniquely remote, placing constraints in regard to communication, environmental uncertainty, and limited physical resources, and requiring a high level of fault tolerance and resistance to hardware degradation. This thesis presents a novel self-reconfiguring autonomous software architecture designed to meet the needs of extraterrestrial planetary environments. At runtime it can safely reconfigure low-level control systems, high-level decisional autonomy systems, and managed software architecture. The architecture can perform automatic Verification and Validation of self-reconfiguration at run-time, and enables a system to be self-optimising, self-protecting, and self-healing. A novel self-monitoring system, which is non-invasive, efficient, tunable, and autonomously deploying, is also presented. The architecture was validated through the use-case of a highly autonomous extra-terrestrial planetary exploration rover. Three major forms of reconfiguration were demonstrated and tested: first, high level adjustment of system internal architecture and goal; second, software module modification; and third, low level alteration of hardware control in response to degradation of hardware and environmental change. The architecture was demonstrated to be robust and effective in a Mars sample return mission use-case testing the operational aspects of a novel, reconfigurable guidance, navigation, and control system for a planetary rover, all operating in concert through a scenario that required reconfiguration of all elements of the system.

  17. Advances in planetary geology, volume 2

    International Nuclear Information System (INIS)

    1986-07-01

    This publication is a continuation of volume 1; it is a compilation of reports focusing on research into the origin and evolution of the solar system with emphasis on planetary geology. Specific reports include a multispectral and geomorphic investigation of the surface of Europa and a geologic interpretation of remote sensing data for the Martian volcano Ascreaus Mons

  18. SPEX: the Spectropolarimeter for Planetary Exploration

    Science.gov (United States)

    Rietjens, J. H. H.; Snik, F.; Stam, D. M.; Smit, J. M.; van Harten, G.; Keller, C. U.; Verlaan, A. L.; Laan, E. C.; ter Horst, R.; Navarro, R.; Wielinga, K.; Moon, S. G.; Voors, R.

    2017-11-01

    We present SPEX, the Spectropolarimeter for Planetary Exploration, which is a compact, robust and low-mass spectropolarimeter designed to operate from an orbiting or in situ platform. Its purpose is to simultaneously measure the radiance and the state (degree and angle) of linear polarization of sunlight that has been scattered in a planetary atmosphere and/or reflected by a planetary surface with high accuracy. The degree of linear polarization is extremely sensitive to the microphysical properties of atmospheric or surface particles (such as size, shape, and composition), and to the vertical distribution of atmospheric particles, such as cloud top altitudes. Measurements as those performed by SPEX are therefore crucial and often the only tool for disentangling the many parameters that describe planetary atmospheres and surfaces. SPEX uses a novel, passive method for its radiance and polarization observations that is based on a carefully selected combination of polarization optics. This method, called spectral modulation, is the modulation of the radiance spectrum in both amplitude and phase by the degree and angle of linear polarization, respectively. The polarization optics consists of an achromatic quarter-wave retarder, an athermal multiple-order retarder, and a polarizing beam splitter. We will show first results obtained with the recently developed prototype of the SPEX instrument, and present a performance analysis based on a dedicated vector radiative transport model together with a recently developed SPEX instrument simulator.

  19. Multiscale regime shifts and planetary boundaries

    NARCIS (Netherlands)

    Hughes, T.P.; Carpenter, S.; Rockstrom, J.; Scheffer, M.; Walker, B.

    2013-01-01

    Life on Earth has repeatedly displayed abrupt and massive changes in the past, and there is no reason to expect that comparable planetary-scale regime shifts will not continue in the future. Different lines of evidence indicate that regime shifts occur when the climate or biosphere transgresses a

  20. Fluorescence Spectra of Blowfly Metaxanthopsins

    NARCIS (Netherlands)

    Kruizinga, B.; Stavenga, D.G.

    The main visual pigment of blowflies (xanthopsin) photoconverts into two thermostable metaxanthopsin states M and M’. The fluorescence spectra of the two photoproducts were studied by microspectrofluorometry in vivo. The emission spectra of M and M’ are very similar and peak at 660 nm. The

  1. Fluorescence Spectra of Highlighter Inks

    Science.gov (United States)

    Birriel, Jennifer J.; King, Damon

    2018-01-01

    Fluorescence spectra excited by laser pointers have been the subject of several papers in TPT. These papers all describe a fluorescence phenomenon in which the reflected laser light undergoes a change in color: this color change results from the combination of some partially reflected laser light and additional colors generated by fluorescent emission. Here we examine the fluorescence spectra of highlighter inks using green and violet laser pointers. We use an RSpec Explorer spectrometer to obtain spectra and compare the emission spectra of blue, green, yellow, orange, pink, and purple highlighters. The website Compound Interest details the chemical composition of highlighter inks; in addition, the site discusses how some base dye colors can be combined to produce the variety commercially available colors. Spectra obtained in this study were qualitatively consistent with the Compound Interest site. We discuss similarities and differences between various highlighter colors and conclude with the relevance of such studies to physics students.

  2. The History of Planetary Exploration Using Mass Spectrometers

    Science.gov (United States)

    Mahaffy, Paul R.

    2012-01-01

    At the Planetary Probe Workshop Dr. Paul Mahaffy will give a tutorial on the history of planetary exploration using mass spectrometers. He will give an introduction to the problems and solutions that arise in making in situ measurements at planetary targets using this instrument class.

  3. Obtaining and Using Planetary Spatial Data into the Future: The Role of the Mapping and Planetary Spatial Infrastructure Team (MAPSIT)

    Science.gov (United States)

    Radebaugh, J.; Thomson, B. J.; Archinal, B.; Hagerty, J.; Gaddis, L.; Lawrence, S. J.; Sutton, S.; Mapsit Steering Committee

    2017-02-01

    Planetary spatial data continue to increase in volume and complexity. These data are the hard-earned fruits of planetary exploration, and MAPSIT’s mission is to ensure their availability for any conceivable investigation, now or in the future.

  4. Planetary Sciences Literature - Access and Discovery

    Science.gov (United States)

    Henneken, Edwin A.; ADS Team

    2017-10-01

    The NASA Astrophysics Data System (ADS) has been around for over 2 decades, helping professional astronomers and planetary scientists navigate, without charge, through the increasingly complex environment of scholarly publications. As boundaries between disciplines dissolve and expand, the ADS provides powerful tools to help researchers discover useful information efficiently. In its new form, code-named ADS Bumblebee (https://ui.adsabs.harvard.edu), it may very well answer questions you didn't know you had! While the classic ADS (http://ads.harvard.edu) focuses mostly on searching basic metadata (author, title and abstract), today's ADS is best described as a an "aggregator" of scholarly resources relevant to the needs of researchers in astronomy and planetary sciences, and providing a discovery environment on top of this. In addition to indexing content from a variety of publishers, data and software archives, the ADS enriches its records by text-mining and indexing the full-text articles (about 4.7 million in total, with 130,000 from planetary science journals), enriching its metadata through the extraction of citations and acknowledgments. Recent technology developments include a new Application Programming Interface (API), a new user interface featuring a variety of visualizations and bibliometric analysis, and integration with ORCID services to support paper claiming. The new ADS provides powerful tools to help you find review papers on a given subject, prolific authors working on a subject and who they are collaborating with (within and outside their group) and papers most read by by people who read recent papers on the topic of your interest. These are just a couple of examples of the capabilities of the new ADS. We currently index most journals covering the planetary sciences and we are striving to include those journals most frequently cited by planetary science publications. The ADS is operated by the Smithsonian Astrophysical Observatory under NASA

  5. Discussion on the spectral coherence between planetary, solar and climate oscillations: a reply to some critiques

    Science.gov (United States)

    Scafetta, Nicola

    2014-12-01

    During the last few years a number of works have proposed that planetary harmonics regulate solar oscillations. Also the Earth's climate seems to present a signature of multiple astronomical harmonics. Herein I address some critiques claiming that planetary harmonics would not appear in the data. I will show that careful and improved analysis of the available data do support the planetary theory of solar and climate variation also in the critiqued cases. In particular, I show that: (1) high-resolution cosmogenic 10Be and 14C solar activity proxy records both during the Holocene and during the Marine Interglacial Stage 9.3 (MIS 9.3), 325-336 kyear ago, present four common spectral peaks (confidence level ⪆95 %) at about 103, 115, 130 and 150 years (this is the frequency band that generates Maunder and Dalton like grand solar minima) that can be deduced from a simple solar model based on a generic non-linear coupling between planetary and solar harmonics; (2) time-frequency analysis and advanced minimum variance distortion-less response (MVDR) magnitude squared coherence analysis confirm the existence of persistent astronomical harmonics in the climate records at the decadal and multidecadal scales when used with an appropriate window lenght ( L≈110 years) to guarantee a sufficient spectral resolution to solve at least the major astronomical harmonics. The optimum theoretical window length deducible from astronomical considerations alone is, however, L⪆178.4 years because the planetary frequencies are harmonics of such a period. However, this length is larger than the available 164-year temperature signal. Thus, the best coherence test can be currently made only using a single window as long as the temperature instrumental record and comparing directly the temperature and astronomical spectra as done in Scafetta (J. Atmos. Sol. Terr. Phys. 72(13):951-970, 2010) and reconfirmed here. The existence of a spectral coherence between planetary, solar and climatic

  6. Improving accessibility and discovery of ESA planetary data through the new planetary science archive

    Science.gov (United States)

    Macfarlane, A. J.; Docasal, R.; Rios, C.; Barbarisi, I.; Saiz, J.; Vallejo, F.; Besse, S.; Arviset, C.; Barthelemy, M.; De Marchi, G.; Fraga, D.; Grotheer, E.; Heather, D.; Lim, T.; Martinez, S.; Vallat, C.

    2018-01-01

    The Planetary Science Archive (PSA) is the European Space Agency's (ESA) repository of science data from all planetary science and exploration missions. The PSA provides access to scientific data sets through various interfaces at http://psa.esa.int. Mostly driven by the evolution of the PDS standards which all new ESA planetary missions shall follow and the need to update the interfaces to the archive, the PSA has undergone an important re-engineering. In order to maximise the scientific exploitation of ESA's planetary data holdings, significant improvements have been made by utilising the latest technologies and implementing widely recognised open standards. To facilitate users in handling and visualising the many products stored in the archive which have spatial data associated, the new PSA supports Geographical Information Systems (GIS) by implementing the standards approved by the Open Geospatial Consortium (OGC). The modernised PSA also attempts to increase interoperability with the international community by implementing recognised planetary science specific protocols such as the PDAP (Planetary Data Access Protocol) and EPN-TAP (EuroPlanet-Table Access Protocol). In this paper we describe some of the methods by which the archive may be accessed and present the challenges that are being faced in consolidating data sets of the older PDS3 version of the standards with the new PDS4 deliveries into a single data model mapping to ensure transparent access to the data for users and services whilst maintaining a high performance.

  7. NASA's Planetary Science Missions and Participations

    Science.gov (United States)

    Daou, Doris; Green, James L.

    2017-04-01

    NASA's Planetary Science Division (PSD) and space agencies around the world are collaborating on an extensive array of missions exploring our solar system. Planetary science missions are conducted by some of the most sophisticated robots ever built. International collaboration is an essential part of what we do. NASA has always encouraged international participation on our missions both strategic (ie: Mars 2020) and competitive (ie: Discovery and New Frontiers) and other Space Agencies have reciprocated and invited NASA investigators to participate in their missions. NASA PSD has partnerships with virtually every major space agency. For example, NASA has had a long and very fruitful collaboration with ESA. ESA has been involved in the Cassini mission and, currently, NASA funded scientists are involved in the Rosetta mission (3 full instruments, part of another), BepiColombo mission (1 instrument in the Italian Space Agency's instrument suite), and the Jupiter Icy Moon Explorer mission (1 instrument and parts of two others). In concert with ESA's Mars missions NASA has an instrument on the Mars Express mission, the orbit-ground communications package on the Trace Gas Orbiter (launched in March 2016) and part of the DLR/Mars Organic Molecule Analyzer instruments going onboard the ExoMars Rover (to be launched in 2018). NASA's Planetary Science Division has continuously provided its U.S. planetary science community with opportunities to include international participation on NASA missions too. For example, NASA's Discovery and New Frontiers Programs provide U.S. scientists the opportunity to assemble international teams and design exciting, focused planetary science investigations that would deepen the knowledge of our Solar System. The PSD put out an international call for instruments on the Mars 2020 mission. This procurement led to the selection of Spain and Norway scientist leading two instruments and French scientists providing a significant portion of another

  8. Planetary Science with Balloon-Borne Telescopes

    Science.gov (United States)

    Kremic, Tibor; Cheng, Andy; Hibbitts, Karl; Young, Eliot

    2015-01-01

    The National Aeronautics and Space Administration (NASA) and the planetary science community have recently been exploring the potential contributions of stratospheric balloons to the planetary science field. A study that was recently concluded explored the roughly 200 or so science questions raised in the Planetary Decadal Survey report and found that about 45 of those questions are suited to stratospheric balloon based observations. In September of 2014, a stratospheric balloon mission called BOPPS (which stands for Balloon Observation Platform for Planetary Science) was flown out of Fort Sumner, New Mexico. The mission had two main objectives, first, to observe a number of planetary targets including one or more Oort cloud comets and second, to demonstrate the applicability and performance of the platform, instruments, and subsystems for making scientific measurements in support planetary science objectives. BOPPS carried two science instruments, BIRC and UVVis. BIRC is a cryogenic infrared multispectral imager which can image in the.6-5 m range using an HgCdTe detector. Narrow band filters were used to allow detection of water and CO2 emission features of the observed targets. The UVVis is an imager with the science range of 300 to 600 nm. A main feature of the UVVis instrument is the incorporation of a guide camera and a Fine Steering Mirror (FSM) system to reduce image jitter to less than 100 milliarcseconds. The BIRC instrument was used to image targets including Oort cloud comets Siding Spring and Jacques, and the dwarf planet 1 Ceres. BOPPS achieved the first ever earth based CO2 observation of a comet and the first images of water and CO2 of an Oort cloud comet (Jacques). It also made the first ever measurement of 1Ceres at 2.73 m to refine the shape of the infrared water absorption feature on that body. The UVVis instrument, mounted on its own optics bench, demonstrated the capability for image correction both from atmospheric disturbances as well as some

  9. Lay and Expert Perceptions of Planetary Protection

    Science.gov (United States)

    Race, Margaret S.; MacGregor, Donald G.; Slovic, Paul

    2000-01-01

    As space scientists and engineers plan new missions to Mars and other planets in our solar system, they will face critical questions about the potential for biological contamination of planetary surfaces. In a society that places ever-increasing importance on the role of public involvement in science and technology policy, questions about risks of biological contamination will be examined and debated in the media, and will lead to the formation of public perceptions of planetary-contamination risks. These perceptions will, over time, form an important input to the development of space policy. Previous research in public and expert perceptions of technological risks and hazards has shown that many of the problems faced by risk-management organizations are the result of differing perceptions of risk (and risk management) between the general public and scientific and technical experts. These differences manifest themselves both as disagreements about the definition (and level) of risk associated with a scientific, technological or industrial enterprise, and as distrust about the ability of risk-management organizations (both public and private) to adequately protect people's health and safety. This report presents the results of a set of survey studies designed to reveal perceptions of planetary exploration and protection from a wide range of respondents, including both members of the general public and experts in the life sciences. The potential value of this research lies in what it reveals about perceptions of risk and benefit that could improve risk-management policies and practices. For example, efforts to communicate with the public about Mars sample return missions could benefit from an understanding of the specific concerns that nonscientists have about such a mission by suggesting areas of potential improvement in public education and information. Assessment of both public and expert perceptions of risk can also be used to provide an advanced signal of

  10. NEUTRON-CAPTURE ELEMENT ABUNDANCES IN MAGELLANIC CLOUD PLANETARY NEBULAE

    Energy Technology Data Exchange (ETDEWEB)

    Mashburn, A. L.; Sterling, N. C. [Department of Physics, University of West Georgia, 1601 Maple Street, Carrollton, GA 30118 (United States); Madonna, S. [Instituto de Astrofísica de Canarias, Departamento Astrofísica, Universidad de La Laguna, E-38206 La Laguna, Tenerife (Spain); Dinerstein, Harriet L. [Department of Astronomy, University of Texas, 2515 Speedway, C1400, Austin, TX 78712-1205 (United States); Roederer, I. U. [Department of Astronomy, University of Michigan, 1085 South University Avenue, Ann Arbor, MI 48109 (United States); Geballe, T. R., E-mail: awhite15@my.westga.edu, E-mail: nsterlin@westga.edu, E-mail: smadonna@iac.es, E-mail: harriet@astro.as.utexas.edu, E-mail: iur@umich.edu, E-mail: tgeballe@gemini.edu [Gemini Observatory, 670 N. A’ohoku Place, Hilo, HI 96720 (United States)

    2016-11-01

    We present near-infrared spectra of 10 planetary nebulae (PNe) in the Large and Small Magellanic Clouds (LMC and SMC), acquired with the FIRE and GNIRS spectrometers on the 6.5 m Baade and 8.1 m Gemini South Telescopes, respectively. We detect Se and/or Kr emission lines in eight of these objects, the first detections of n -capture elements in Magellanic Cloud PNe. Our abundance analysis shows large s -process enrichments of Kr (0.6–1.3 dex) in the six PNe in which it was detected, and Se is enriched by 0.5–0.9 dex in five objects. We also estimate upper limits to Rb and Cd abundances in these objects. Our abundance results for the LMC are consistent with the hypothesis that PNe with 2–3 M {sub ⊙} progenitors dominate the bright end of the PN luminosity function in young gas-rich galaxies. We find no significant correlations between s -process enrichments and other elemental abundances, central star temperature, or progenitor mass, though this is likely due to our small sample size. We determine S abundances from our spectra and find that [S/H] agrees with [Ar/H] to within 0.2 dex for most objects, but is lower than [O/H] by 0.2–0.4 dex in some PNe, possibly due to O enrichment via third dredge-up. Our results demonstrate that n -capture elements can be detected in PNe belonging to nearby galaxies with ground-based telescopes, allowing s -process enrichments to be studied in PN populations with well-determined distances.

  11. Raman spectra of lithium compounds

    Science.gov (United States)

    Gorelik, V. S.; Bi, Dongxue; Voinov, Y. P.; Vodchits, A. I.; Gorshunov, B. P.; Yurasov, N. I.; Yurasova, I. I.

    2017-11-01

    The paper is devoted to the results of investigating the spontaneous Raman scattering spectra in the lithium compounds crystals in a wide spectral range by the fibre-optic spectroscopy method. We also present the stimulated Raman scattering spectra in the lithium hydroxide and lithium deuteride crystals obtained with the use of powerful laser source. The symmetry properties of the lithium hydroxide, lithium hydroxide monohydrate and lithium deuteride crystals optical modes were analyzed by means of the irreducible representations of the point symmetry groups. We have established the selection rules in the Raman and infrared absorption spectra of LiOH, LiOH·H2O and LiD crystals.

  12. The Role of Planetary Data System Archive Standards in International Planetary Data Archives

    Science.gov (United States)

    Guinness, Edward; Slavney, Susan; Beebe, Reta; Crichton, Daniel

    A major objective of NASA's Planetary Data System (PDS) is to efficiently archive and make accessible digital data produced by NASA's planetary missions, research programs, and data analysis programs. The PDS is comprised of a federation of groups known as nodes, with each node focused on archiving and managing planetary data from a given science discipline. PDS nodes include Atmospheres, Geosciences, Small Bodies (asteroids, comets, and dust), Rings, Planetary Plasma Interactions, and Imaging. There are also support nodes for engineering, radio science, and ancillary data, such as geometry information. The PDS archives include space-borne, ground-based, and laboratory experiment data from several decades of NASA exploration of comets, asteroids, moons, and planets. PDS archives are peer-reviewed, welldocumented, and accessible online via web sites, catalogs, and other user-interfaces that provide search and retrieval capabilities. Current holdings within the PDS online repositories total approximately 50 TB of data. Over the next few years, the PDS is planning for a rapid expansion in the volume of data being delivered to its archives. The archive standards developed by the PDS are crucial elements for producing planetary data archives that are consistent across missions and planetary science disciplines and that yield archives that are useable by the planetary research community. These standards encompass the full range of archiving needs. They include standards for the format of data products and the metadata needed to detail how observations were made. They also specify how data products and ancillary information such as documentation, calibration, and geometric information are packaged into data sets. The PDS standards are documented in its Planetary Science Data Dictionary and in its Standards Reference Document and Archive Preparation Guide. The PDS standards are being used to design and implement data archives for current and future NASA planetary missions

  13. From red giants to planetary nebulae: Asymmetries, dust, and polarization

    International Nuclear Information System (INIS)

    Johnson, J.J.

    1990-01-01

    In order to investigate the development of aspherical planetary nebulae, polarimetry was obtained for a group of planetary nebulae and for objects that will evolve into planetary nebulae, i.e., red giants, late asymptotic giant branch (AGB) objects, proto-planetary nebulae, and young planetary nebulae. To study the dust around the objects in our sample, we also used data from the Infrared Astronomy Satellite (IRAS) mission. The youngest objects in our survey, red giants, had the hottest dust temperatures while planetary nebulae had the coolest. Most of the objects were intrinsically polarized, including the red giants. This indicated that the circumstellar dust shells of these objects were aspherical. Both carbon- and oxygen-rich objects could be intrinsically polarized. The intrinsic polarizations of a sample of our objects were modeled using an ellipsoidal circumstellar dust shell. The findings of this study suggest that the asphericities that lead to an aspherical planetary nebula originate when a red giant begins to undergo mass loss. The polarization and thus the asphericity as the star evolves, with both reaching a maximum during the proto-planetary nebula stage. The circumstellar dust shell will dissipate after the proto-planetary nebulae stage since no new material is being added. The polarization of planetary nebulae will thus be low. In the most evolved planetary nebulae, the dust has either been destroyed or dissipated into the interstellar medium. In these objects no polarization was observed

  14. Fault diagnosis for wind turbine planetary ring gear via a meshing resonance based filtering algorithm.

    Science.gov (United States)

    Wang, Tianyang; Chu, Fulei; Han, Qinkai

    2017-03-01

    Identifying the differences between the spectra or envelope spectra of a faulty signal and a healthy baseline signal is an efficient planetary gearbox local fault detection strategy. However, causes other than local faults can also generate the characteristic frequency of a ring gear fault; this may further affect the detection of a local fault. To address this issue, a new filtering algorithm based on the meshing resonance phenomenon is proposed. In detail, the raw signal is first decomposed into different frequency bands and levels. Then, a new meshing index and an MRgram are constructed to determine which bands belong to the meshing resonance frequency band. Furthermore, an optimal filter band is selected from this MRgram. Finally, the ring gear fault can be detected according to the envelope spectrum of the band-pass filtering result. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  15. Aspirated capacitor measurements of air conductivity and ion mobility spectra

    International Nuclear Information System (INIS)

    Aplin, K.L.

    2005-01-01

    Measurements of ions in atmospheric air are used to investigate atmospheric electricity and particulate pollution. Commonly studied ion parameters are (1) air conductivity, related to the total ion number concentration, and (2) the ion mobility spectrum, which varies with atmospheric composition. The physical principles of air ion instrumentation are long established. A recent development is the computerized aspirated capacitor, which measures ions from (a) the current of charged particles at a sensing electrode, and (b) the rate of charge exchange with an electrode at a known initial potential, relaxing to a lower potential. As the voltage decays, only ions of higher and higher mobility are collected by the central electrode and contribute to the further decay of the voltage. This enables extension of the classical theory to calculate ion mobility spectra by inverting voltage decay time series. In indoor air, ion mobility spectra determined from both the voltage decay inversion, and an established voltage switching technique, were compared and shown to be of similar shape. Air conductivities calculated by integration were: 5.3±2.5 and 2.7±1.1 fSm -1 , respectively, with conductivity determined to be 3 fSm -1 by direct measurement at a constant voltage. Applications of the relaxation potential inversion method include air ion mobility spectrum retrieval from historical data, and computation of ion mobility spectra in planetary atmospheres

  16. Infrared spectra of mineral species

    CERN Document Server

    Chukanov, Nikita V

    2014-01-01

    This book details more than 3,000 IR spectra of more than 2,000 mineral species collected during last 30 years. It features full descriptions and analytical data of each sample for which IR spectrum was obtained.

  17. The Next Generation of Planetary Atmospheric Probes

    Science.gov (United States)

    Houben, Howard

    2005-01-01

    Entry probes provide useful insights into the structures of planetary atmospheres, but give only one-dimensional pictures of complex four-dimensional systems that vary on all temporal and spatial scales. This makes the interpretation of the results quite challenging, especially as regards atmospheric dynamics. Here is a planetary meteorologist's vision of what the next generation of atmospheric entry probe missions should be: Dedicated sounding instruments get most of the required data from orbit. Relatively simple and inexpensive entry probes are released from the orbiter, with low entry velocities, to establish ground truth, to clarify the vertical structure, and for adaptive observations to enhance the dataset in preparation for sensitive operations. The data are assimilated onboard in real time. The products, being immediately available, are of immense benefit for scientific and operational purposes (aerobraking, aerocapture, accurate payload delivery via glider, ballooning missions, weather forecasts, etc.).

  18. Laser Mass Spectrometry in Planetary Science

    International Nuclear Information System (INIS)

    Wurz, P.; Whitby, J. A.; Managadze, G. G.

    2009-01-01

    Knowing the chemical, elemental, and isotopic composition of planetary objects allows the study of their origin and evolution within the context of our solar system. Exploration plans in planetary research of several space agencies consider landing spacecraft for future missions. Although there have been successful landers in the past, more landers are foreseen for Mars and its moons, Venus, the jovian moons, and asteroids. Furthermore, a mass spectrometer on a landed spacecraft can assist in the sample selection in a sample-return mission and provide mineralogical context, or identify possible toxic soils on Mars for manned Mars exploration. Given the resources available on landed spacecraft mass spectrometers, as well as any other instrument, have to be highly miniaturised.

  19. Europa Planetary Protection for Juno Jupiter Orbiter

    Science.gov (United States)

    Bernard, Douglas E.; Abelson, Robert D.; Johannesen, Jennie R.; Lam, Try; McAlpine, William J.; Newlin, Laura E.

    2010-01-01

    NASA's Juno mission launched in 2011 and will explore the Jupiter system starting in 2016. Juno's suite of instruments is designed to investigate the atmosphere, gravitational fields, magnetic fields, and auroral regions. Its low perijove polar orbit will allow it to explore portions of the Jovian environment never before visited. While the Juno mission is not orbiting or flying close to Europa or the other Galilean satellites, planetary protection requirements for avoiding the contamination of Europa have been taken into account in the Juno mission design.The science mission is designed to conclude with a deorbit burn that disposes of the spacecraft in Jupiter's atmosphere. Compliance with planetary protection requirements is verified through a set of analyses including analysis of initial bioburden, analysis of the effect of bioburden reduction due to the space and Jovian radiation environments, probabilistic risk assessment of successful deorbit, Monte-Carlo orbit propagation, and bioburden reduction in the event of impact with an icy body.

  20. Multiscale regime shifts and planetary boundaries.

    Science.gov (United States)

    Hughes, Terry P; Carpenter, Stephen; Rockström, Johan; Scheffer, Marten; Walker, Brian

    2013-07-01

    Life on Earth has repeatedly displayed abrupt and massive changes in the past, and there is no reason to expect that comparable planetary-scale regime shifts will not continue in the future. Different lines of evidence indicate that regime shifts occur when the climate or biosphere transgresses a tipping point. Whether human activities will trigger such a global event in the near future is uncertain, due to critical knowledge gaps. In particular, we lack understanding of how regime shifts propagate across scales, and whether local or regional tipping points can lead to global transitions. The ongoing disruption of ecosystems and climate, combined with unprecedented breakdown of isolation by human migration and trade, highlights the need to operate within safe planetary boundaries. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. N-body simulations of planetary formation

    Science.gov (United States)

    Beauge, C.; Aarseth, S. J.

    1990-07-01

    Numerical simulations of the last stage of terrestrial planetary formation are performed using an N-body code similar to that of Lecar and Aarseth (1986). An improved treatment of collisions has been applied, which allows fragmentation and cratering, as well as accretion. Initial models consist of 200 bodies of total mass 2.3 x 10 to the 28th g, distributed in a two-dimensional ring of size 1 AU with initial circular orbits about the sun. Planetary embryos begin to form by accretion in the early stages when the relative velocities are small. Eventually, a small number of massive embryos emerge, and subsequently accrete nearly all the fragments. Final configurations of three different models yield four principal bodies with moderate eccentricities on a time-scale of 500,000 yr.

  2. Lunar and Planetary Webcam User's Guide

    CERN Document Server

    Mobberley, Martin

    2006-01-01

    Inexpensive webcams are revolutionizing imaging in amateur astronomy by providing an affordable alternative to cooled-chip astronomical CCD cameras, for photographing the brighter astronomical objects. Webcams – costing only a few tens of dollars – are capable of more advanced high resolution work than "normal" digital cameras because their rapid image download speed can freeze fine planetary details, even through the Earth's turbulent atmosphere. Also, their simple construction makes it easy to remove the lens, allowing them to be used at high power at the projected focus of an astronomical telescope. Webcams also connect direct to a PC, so that software can be used to "stack" multiple images, providing a stunning increase in image quality. In the Lunar and Planetary Webcam User’s Guide Martin Mobberley de-mystifies the jargon of webcams and computer processing, and provides detailed hints and tips for imaging the Sun, Moon and planets with a webcam. He looks at each observing target separately, descri...

  3. The planetary rate of sprite events

    DEFF Research Database (Denmark)

    Ignaccolo, M.; Farges, T.; Mika, A.

    2006-01-01

    We propose a new formula to calculate the planetary rate of sprite events, based on observations with sprite detectors. This formula uses the number of detected sprites, the detection efficiency and the false alarm rate of the detector and spatial and temporal effectiveness functions. The role...... of these elements in the formula is discussed for optical and non-optical recordings. We use the formula to calculate an average planetary rate of sprite events of similar to 2.8 per minute with an accuracy of a factor similar to 2 - 3 by use of observations reported in the literature. The proposed formula can...... be used to calculate the occurrence rate of any physical event detected by remote sensing....

  4. Sequential Analysis of Gamma Spectra

    International Nuclear Information System (INIS)

    Fayez-Hassan, M.; Hella, Kh.M.

    2009-01-01

    This work shows how easy one can deal with a huge number of gamma spectra. The method can be used for radiation monitoring. It is based on the macro feature of the windows XP connected to QBASIC software. The routine was used usefully in generating accurate results free from human errors. One hundred measured gamma spectra were fully analyzed in 10 minutes using our fast and automated method controlling the Genie 2000 gamma acquisition analysis software.

  5. Communication System Architecture for Planetary Exploration

    Science.gov (United States)

    Braham, Stephen P.; Alena, Richard; Gilbaugh, Bruce; Glass, Brian; Norvig, Peter (Technical Monitor)

    2001-01-01

    Future human missions to Mars will require effective communications supporting exploration activities and scientific field data collection. Constraints on cost, size, weight and power consumption for all communications equipment make optimization of these systems very important. These information and communication systems connect people and systems together into coherent teams performing the difficult and hazardous tasks inherent in planetary exploration. The communication network supporting vehicle telemetry data, mission operations, and scientific collaboration must have excellent reliability, and flexibility.

  6. Planetary Sciences: American and Soviet Research

    Science.gov (United States)

    Donahue, Thomas M. (Editor); Trivers, Kathleen Kearney (Editor); Abramson, David M. (Editor)

    1991-01-01

    Papers presented at the US-USSR Workshop on Planetary Sciences are compiled. The purpose of the workshop was to examine the current state of theoretical understanding of how the planets were formed and how they evolved to their present state. The workshop assessed the types of observations and experiments that are needed to advance understanding of the formation and evolution of the solar system based on the current theoretical framework.

  7. Planetary atmospheric physics and solar physics research

    Science.gov (United States)

    1973-01-01

    An overview is presented on current and planned research activities in the major areas of solar physics, planetary atmospheres, and space astronomy. The approach to these unsolved problems involves experimental techniques, theoretical analysis, and the use of computers to analyze the data from space experiments. The point is made that the research program is characterized by each activity interacting with the other activities in the laboratory.

  8. Large-Scale Structures of Planetary Systems

    Science.gov (United States)

    Murray-Clay, Ruth; Rogers, Leslie A.

    2015-12-01

    A class of solar system analogs has yet to be identified among the large crop of planetary systems now observed. However, since most observed worlds are more easily detectable than direct analogs of the Sun's planets, the frequency of systems with structures similar to our own remains unknown. Identifying the range of possible planetary system architectures is complicated by the large number of physical processes that affect the formation and dynamical evolution of planets. I will present two ways of organizing planetary system structures. First, I will suggest that relatively few physical parameters are likely to differentiate the qualitative architectures of different systems. Solid mass in a protoplanetary disk is perhaps the most obvious possible controlling parameter, and I will give predictions for correlations between planetary system properties that we would expect to be present if this is the case. In particular, I will suggest that the solar system's structure is representative of low-metallicity systems that nevertheless host giant planets. Second, the disk structures produced as young stars are fed by their host clouds may play a crucial role. Using the observed distribution of RV giant planets as a function of stellar mass, I will demonstrate that invoking ice lines to determine where gas giants can form requires fine tuning. I will suggest that instead, disk structures built during early accretion have lasting impacts on giant planet distributions, and disk clean-up differentially affects the orbital distributions of giant and lower-mass planets. These two organizational hypotheses have different implications for the solar system's context, and I will suggest observational tests that may allow them to be validated or falsified.

  9. Earth-like Habitats in Planetary Systems

    OpenAIRE

    Fritz, Jörg; Bitsch, Bertram; Kührt, Ekkehard; Morbidelli, Alessandro; Tornow, Carmen; Wünnemann, Kai; Fernandes, Vera A.; Grenfell, Lee J.; Rauer, Heike; Wagner, Roland; Werner, Stephanie C.

    2014-01-01

    Understanding the concept of habitability is related to an evolutionary knowledge of the particular planet-in-question. Additional indications so-called "systemic aspects" of the planetary system as a whole governs a particular planet's claim on habitability. Here we focus on such systemic aspects and discuss their relevance to the formation of an 'Earth-like' habitable planet. We summarize our results obtained by lunar sample work and numerical models within the framework of the Research All...

  10. Robots and humans: synergy in planetary exploration

    Science.gov (United States)

    Landis, Geoffrey A.

    2004-01-01

    How will humans and robots cooperate in future planetary exploration? Are humans and robots fundamentally separate modes of exploration, or can humans and robots work together to synergistically explore the solar system? It is proposed that humans and robots can work together in exploring the planets by use of telerobotic operation to expand the function and usefulness of human explorers, and to extend the range of human exploration to hostile environments. Published by Elsevier Ltd.

  11. Search for binary nuclei in planetary nebulae

    International Nuclear Information System (INIS)

    Jasniewicz, G.

    1987-01-01

    Two planetary nebulae with central stars of late spectral type were observed: LT 5 and Abell 35. The variation of the systemic velocity of the G-binary in HD 112313 gives strong support to the idea of a third body in the nucleus of LT 5. In addition, it is concluded that observed photometric variations of BD -22 deg 3467 (the central star of Abell 35) can best be explained by the binary nature of the star. 9 references

  12. Search for binary nuclei in planetary nebulae

    Science.gov (United States)

    Jasniewicz, G.

    Two planetary nebulae with central stars of late spectral type were observed: LT 5 and Abell 35. The variation of the systemic velocity of the G-binary in HD 112313 gives strong support to the idea of a third body in the nucleus of LT 5. In addition, it is concluded that observed photometric variations of BD -22 deg 3467 (the central star of Abell 35) can best be explained by the binary nature of the star.

  13. Response spectra in alluvial soils

    International Nuclear Information System (INIS)

    Chandrasekharan, A.R.; Paul, D.K.

    1975-01-01

    For aseismic design of structures, the ground motion data is assumed either in the form of ground acceleration as a function of time or indirectly in the form of response spectra. Though the response spectra approach has limitations like not being applicable for nonlinear problems, it is usually used for structures like nuclear power plants. Fifty accelerograms recorded at alluvial sites have been processed. Since different empirical formulas relating acceleration with magnitude and distance give a wide scatter of values, peak ground acceleration alone cannot be the parameter as is assumed by a number of authors. The spectra corresponding to 5% damping have been normalised with respect to three parameters, namely, peak ground acceleration, peak ground velocity and a nondimensional quantity ad/v 2 . Envelopee of maxima and minima as well as average response spectra has been obtained. A comparison with the USAEC spectra has been made. A relation between ground acceleration, ground velocity and ad/v 2 has been obtained which would nearly give the same magnification of the response. A design response spectra for alluvial soils has been recommended. (author)

  14. Russian Planetary Exploration History, Development, Legacy, Prospects

    CERN Document Server

    Harvey, Brian

    2007-01-01

    Russia’s accomplishments in planetary space exploration were not achieved easily. Formerly, the USSR experienced frustration in trying to tame unreliable Molniya and Proton upper stages and in tracking spacecraft over long distances. This book will assess the scientific haul of data from the Venus and Mars missions and look at the engineering approaches. The USSR developed several generations of planetary probes: from MV and Zond to the Phobos type. The engineering techniques used and the science packages are examined, as well as the nature of the difficulties encountered which ruined several missions. The programme’s scientific and engineering legacy is also addressed, as well as its role within the Soviet space programme as a whole. Brian Harvey concludes by looking forward to future Russian planetary exploration (e.g Phobos Grunt sample return mission). Several plans have been considered and may, with a restoration of funding, come to fruition. Soviet studies of deep space and Mars missions (e.g. TMK, ...

  15. Chemical kinetics and modeling of planetary atmospheres

    Science.gov (United States)

    Yung, Yuk L.

    1990-01-01

    A unified overview is presented for chemical kinetics and chemical modeling in planetary atmospheres. The recent major advances in the understanding of the chemistry of the terrestrial atmosphere make the study of planets more interesting and relevant. A deeper understanding suggests that the important chemical cycles have a universal character that connects the different planets and ultimately link together the origin and evolution of the solar system. The completeness (or incompleteness) of the data base for chemical kinetics in planetary atmospheres will always be judged by comparison with that for the terrestrial atmosphere. In the latter case, the chemistry of H, O, N, and Cl species is well understood. S chemistry is poorly understood. In the atmospheres of Jovian planets and Titan, the C-H chemistry of simple species (containing 2 or less C atoms) is fairly well understood. The chemistry of higher hydrocarbons and the C-N, P-N chemistry is much less understood. In the atmosphere of Venus, the dominant chemistry is that of chlorine and sulfur, and very little is known about C1-S coupled chemistry. A new frontier for chemical kinetics both in the Earth and planetary atmospheres is the study of heterogeneous reactions. The formation of the ozone hole on Earth, the ubiquitous photochemical haze on Venus and in the Jovian planets and Titan all testify to the importance of heterogeneous reactions. It remains a challenge to connect the gas phase chemistry to the production of aerosols.

  16. Reconstruction and visualization of planetary nebulae.

    Science.gov (United States)

    Magnor, Marcus; Kindlmann, Gordon; Hansen, Charles; Duric, Neb

    2005-01-01

    From our terrestrially confined viewpoint, the actual three-dimensional shape of distant astronomical objects is, in general, very challenging to determine. For one class of astronomical objects, however, spatial structure can be recovered from conventional 2D images alone. So-called planetary nebulae (PNe) exhibit pronounced symmetry characteristics that come about due to fundamental physical processes. Making use of this symmetry constraint, we present a technique to automatically recover the axisymmetric structure of many planetary nebulae from photographs. With GPU-based volume rendering driving a nonlinear optimization, we estimate the nebula's local emission density as a function of its radial and axial coordinates and we recover the orientation of the nebula relative to Earth. The optimization refines the nebula model and its orientation by minimizing the differences between the rendered image and the original astronomical image. The resulting model allows creating realistic 3D visualizations of these nebulae, for example, for planetarium shows and other educational purposes. In addition, the recovered spatial distribution of the emissive gas can help astrophysicists gain deeper insight into the formation processes of planetary nebulae.

  17. HM Sagittae as a young planetary nebula

    International Nuclear Information System (INIS)

    Kwok, S.; Purton, C.R.

    1979-01-01

    HM Sagittae is suggested to be a very young planetary nebula recently transformed from a red-giant star through continuous mass loss. The observational data for HM Sge have been analyzed in terms of the interacting stellar wind model of planetary nebula formation. The model is in accord with virtually all the spectral data available--radio, optical, and infrared--as well as with the remarkable brightening of HM Sge observed in 1975. In particular, all three gaseous components predicted by the model are observed in the optical spectrum. The density in the newly formed shell is found to be at least 5 x 10 7 cm -3 , a value considerably higher than that found by the conventional analysis, which assumes a single-component homogeneous nebula. The radio spectrum is dominated by free-free emission from the remnant red-giant wind. The infrared spectrum suggests the presence of two dust components, one consisting of silicate grains left over from the red-giant stage and the other of grains newly formed after the 1975 brightening. The low observed shell mass is consistent with the interacting stellar wind model but is not consistent with the conventional sudden-ejection model of planetary nebula formation

  18. The European standard on planetary protection requirements.

    Science.gov (United States)

    Debus, André

    2006-01-01

    Since the beginning of solar system exploration, numerous spacecrafts have been sent towards others worlds, and one of the main goals of such missions is the search for extraterrestrial forms of life. It is known that, under certain conditions, some terrestrial entities are able to survive during cruises in space and that they may contaminate other planets (forward contamination). At another level, possible extraterrestrial life forms are unknown and their ability to contaminate the Earth's biosphere (back contamination) in the frame of sample return missions cannot be excluded. Article IX of the Outer Space Treaty (London/Washington, January 27, 1967) requires the preservation of planets and the Earth from contamination. All nations taking part in this Treaty must prevent forward and back contamination during missions exploring our solar system. Consequently, the United Nations (UN-COPUOS) has delegated COSPAR (Committee of Space Research) to take charge of planetary protection and, at present, all space-faring nations must comply with COSPAR policy and consequently with COSPAR planetary protection recommendations. Starting from these recommendations and the "CNES Planetary Protection Standard" document, a working group has been set up in the framework of the "European Cooperation for Space Standardization" (ECSS) to establish the main specifications for preventing cross-contamination between target bodies within the solar system and the Earth-moon system.

  19. INVITED TALK: Dynamics Of Planetary Rings

    Science.gov (United States)

    Tiscareno, Matthew S.

    2011-04-01

    Planetary rings are the only nearby astrophysical disks, and the only disks that have been investigated by spacecraft (especially the Cassini spacecraft orbiting Saturn). Although there are significant differences between rings and other disks, chiefly the large planet/ring mass ratio that greatly enhances the flatness of rings (aspect ratios as small as 1e-7), understanding of disks in general can be enhanced by understanding the dynamical processes observed at close-range and in real-time in planetary rings. We will review the known ring systems of the four giant planets, as well as the prospects for ring systems yet to be discovered. We will then review planetary rings by type. The A, B, and C rings of Saturn, plus the Cassini Division, comprise our solar system's only dense broad disk and host many phenomena of general application to disks including spiral waves, gap formation, self-gravity wakes, viscous overstability and normal modes, impact clouds, and orbital evolution of embedded moons. Dense narrow rings are found both at Uranus (where they comprise the main rings entirely) and at Saturn (where they are embedded in the broad disk), and are the primary natural laboratory for understanding shepherding and self-stability. Narrow dusty rings, likely generated by embedded source bodies, are surprisingly found to sport azimuthally-confined arcs both at Saturn, Jupiter, and Neptune. Finally, every known ring system includes a substantial component of diffuse dusty rings.

  20. Interstellar and Planetary Analogs in the Laboratory

    Science.gov (United States)

    Salama, Farid

    2013-01-01

    We present and discuss the unique capabilities of the laboratory facility, COSmIC, that was developed at NASA Ames to investigate the interaction of ionizing radiation (UV, charged particles) with molecular species (neutral molecules, radicals and ions) and carbonaceous grains in the Solar System and in the Interstellar Medium (ISM). COSmIC stands for Cosmic Simulation Chamber, a laboratory chamber where interstellar and planetary analogs are generated, processed and analyzed. It is composed of a pulsed discharge nozzle (PDN) expansion that generates a free jet supersonic expansion in a plasma cavity coupled to two ultrahigh-sensitivity, complementary in situ diagnostics: a cavity ring down spectroscopy (CRDS) system for photonic detection and a Reflectron time-of-flight mass spectrometer (ReTOF-MS) for mass detection. This setup allows the study of molecules, ions and solids under the low temperature and high vacuum conditions that are required to simulate some interstellar, circumstellar and planetary physical environments providing new fundamental insights on the molecular level into the processes that are critical to the chemistry in the ISM, circumstellar and planet forming regions, and on icy objects in the Solar System. Recent laboratory results that were obtained using COSmIC will be discussed, in particular the progress that have been achieved in monitoring in the laboratory the formation of solid particles from their gas-phase molecular precursors in environments as varied as circumstellar outflow and planetary atmospheres.

  1. SmallSat Innovations for Planetary Science

    Science.gov (United States)

    Weinberg, Jonathan; Petroy, Shelley; Roark, Shane; Schindhelm, Eric

    2017-10-01

    As NASA continues to look for ways to fly smaller planetary missions such as SIMPLEX, MoO, and Venus Bridge, it is important that spacecraft and instrument capabilities keep pace to allow these missions to move forward. As spacecraft become smaller, it is necessary to balance size with capability, reliability and payload capacity. Ball Aerospace offers extensive SmallSat capabilities matured over the past decade, utilizing our broad experience developing mission architecture, assembling spacecraft and instruments, and testing advanced enabling technologies. Ball SmallSats inherit their software capabilities from the flight proven Ball Configurable Platform (BCP) line of spacecraft, and may be tailored to meet the unique requirements of Planetary Science missions. We present here recent efforts in pioneering both instrument miniaturization and SmallSat/sensorcraft development through mission design and implementation. Ball has flown several missions with small, but capable spacecraft. We also have demonstrated a variety of enhanced spacecraft/instrument capabilities in the laboratory and in flight to advance autonomy in spaceflight hardware that can enable some small planetary missions.

  2. Degassing of reduced carbon from planetary basalts.

    Science.gov (United States)

    Wetzel, Diane T; Rutherford, Malcolm J; Jacobsen, Steven D; Hauri, Erik H; Saal, Alberto E

    2013-05-14

    Degassing of planetary interiors through surface volcanism plays an important role in the evolution of planetary bodies and atmospheres. On Earth, carbon dioxide and water are the primary volatile species in magmas. However, little is known about the speciation and degassing of carbon in magmas formed on other planets (i.e., Moon, Mars, Mercury), where the mantle oxidation state [oxygen fugacity (fO2)] is different from that of the Earth. Using experiments on a lunar basalt composition, we confirm that carbon dissolves as carbonate at an fO2 higher than -0.55 relative to the iron wustite oxygen buffer (IW-0.55), whereas at a lower fO2, we discover that carbon is present mainly as iron pentacarbonyl and in smaller amounts as methane in the melt. The transition of carbon speciation in mantle-derived melts at fO2 less than IW-0.55 is associated with a decrease in carbon solubility by a factor of 2. Thus, the fO2 controls carbon speciation and solubility in mantle-derived melts even more than previous data indicate, and the degassing of reduced carbon from Fe-rich basalts on planetary bodies would produce methane-bearing, CO-rich early atmospheres with a strong greenhouse potential.

  3. Distribution of scientific data from ESA's planetary missions via the Planetary Science Archive (PSA)

    Science.gov (United States)

    Heather, D.; Zender, J.; Arviset, C.

    The Planetary Science Archive (PSA) is an online archive facility supporting all of ESA's planetary missions. Scientific and ancillary data from all of ESA's planetary missions will be distributed via the PSA, which is open to the worldwide scientific community, and should be the first port of call for all scientists looking for ESA planetary data. Currently, the PSA contains data from Giotto, several ground-based observatories, and Mars Express. In the long run, the PSA will also be the repository for missions such as Huygens, SMART-1, Rosetta and Venus Express. This presentation gives a demonstration of the use and functionality of the PSA to show how data products and data sets should be queried, requested and retrieved from the archive. An overview of the data flow from the spacecraft to the scientific community is also provided. The data release policy and the envisaged schedule of the expected data releases are given, and the archive process is detailed including the definition of data types and products, database ingestion and reviews for all instruments on-board ESA's planetary missions.

  4. Central Stars of Planetary Nebulae in the SMC

    Science.gov (United States)

    Bianchi, Luciana

    2004-01-01

    In FUSE cycle 3's program C056 we studied four Central Stars of Planetary Nebulae (CSPN) in the Small Magellanic Could. All FUSE observations have been successfully completed and have been reduced and analyzed. The observation of one object (SMP SMC 5) appeared to be off-target and no useful stellar flux was gathered. For another observation (SMP SMC 1) the voltage problems resulted in the loss of data from one of the SiC detectors, but we were still able to analyze the remaining data. The analysis and the results are summarized below. The FUSE data were reduced using the latest available version of the FUSE calibration pipeline (CALFUSE v2.4). The flux of these SMC post-AGB objects is at the threshold of FUSE S sensitivity, and the targets required many orbit-long exposures, each of which typically had low (target) count-rates. The background subtraction required special care during the reduction, and was done in a similar manner to our FUSE cycle 2 BOO1 objects. The resulting calibrated data from the different channels were compared in the overlapping regions for consistency. The final combined, extracted spectra of each target was then modeled to determine the stellar and nebular parameters. The FUSE spectra, combined with archival HST spectra, have been analyzed using stellar atmospheres codes such as TLUSTY and CMFGEN to derive photospheric and wind parameters of the central stars, and with ISM models to determine the amount and temperature of the surrounding atomic and molecular hydrogen. We have combined these results with those of our cycle 4 (D034) program (CSPN of the LMC) in Herald & Bianchi 2004a (paper in preparation, will be submitted to ApJ in June 2004). Two of the three SMC objects analyzed were found to have significantly lower stellar temperatures than had been predicted using nebular photoionization models, indicating either a hotter ionizing companion or the existence of strong shocks in the nebular environment. The analysis also revealed that

  5. Lunar and Planetary Science XXXV: Asteroids, Meteors, Comets

    Science.gov (United States)

    2004-01-01

    Reports included:Long Term Stability of Mars Trojans; Horseshoe Asteroids and Quasi-satellites in Earth-like Orbits; Effect of Roughness on Visible Reflectance Spectra of Planetary Surface; SUBARU Spectroscopy of Asteroid (832) Karin; Determining Time Scale of Space Weathering; Change of Asteroid Reflectance Spectra by Space Weathering: Pulse Laser Irradiation on Meteorite Samples; Reflectance Spectra of CM2 Chondrite Mighei Irradiated with Pulsed Laser and Implications for Low-Albedo Asteroids and Martian Moons; Meteorite Porosities and Densities: A Review of Trends in the Data; Small Craters in the Inner Solar System: Primaries or Secondaries or Both?; Generation of an Ordinary-Chondrite Regolith by Repetitive Impact; Asteroid Modal Mineralogy Using Hapke Mixing Models: Validation with HED Meteorites; Particle Size Effect in X-Ray Fluorescence at a Large Phase Angle: Importance on Elemental Analysis of Asteroid Eros (433); An Investigation into Solar Wind Depletion of Sulfur in Troilite; Photometric Behaviour Dependent on Solar Phase Angle and Physical Characteristics of Binary Near-Earth-Asteroid (65803) 1996 GT; Spectroscopic Observations of Asteroid 4 Vesta from 1.9 to 3.5 micron: Evidence of Hydrated and/or Hydroxylated Minerals; Multi-Wavelength Observations of Asteroid 2100 Ra-Shalom: Visible, Infrared, and Thermal Spectroscopy Results; New Peculiarities of Cometary Outburst Activity; Preliminary Shape Modeling for the Asteroid (25143) Itokawa, AMICA of Hayabusa Mission; Scientific Capability of MINERVA Rover in Hayabusa Asteroid Mission; Characteristics and Current Status of Near Infrared Spectrometer for Hayabusa Mission; Sampling Strategy and Curation Plan of Hayabusa Asteroid Sample Return Mission; Visible/Near-Infrared Spectral Properties of MUSES C Target Asteroid 25143 Itokawa; Calibration of the NEAR XRS Solar Monitor; Modeling Mosaic Degradation of X-Ray Measurements of 433 Eros by NEAR-Shoemaker; Scattered Light Remediation and Recalibration of

  6. Calibration Transfer in LIBS and Raman Spectroscopy for Planetary Applications

    Science.gov (United States)

    Dyar, M. D.; Thomas, B. F.; Parente, M.; Gemp, I.; Mullen, T. H.

    2017-12-01

    Planetary scientists rely on spectral libraries and instrument reproducibility to interpret results from missions. Major investments have been made into assembling libraries, but they often naively assume that spectra of single crystals versus powders and from varying instruments will be the same. Calibration transfer (CT) seeks to algorithmically resolve discrepancies among datasets from different instruments or conditions. It offers the ability to align suites of spectra with a small number of common samples, allowing better models to be built with combined data sets. LIBS and Raman data present different challenges for CT. Quantitative geochemical analyses by LIBS spectroscopy are limited by lack of consistency among repeated laser shots and across instruments. Many different factors affect the presence/absence of emission lines and their intensities, such as laser power/plasma temperature, angle of incidence, detector sensitivity/resolution. To overcome these, models in which disparate datasets are projected into a joint low-dimensional subspace where all data can be aligned before quantitative analysis, such as Correlation Analysis for Domain Adaptation (CADA), have proven very effective. They require some overlap between the populations of spectra to be aligned. For example, prediction of SiO2 on 80 samples from two different LIBS labs show errors of ±16-29 wt.% when the training and test sets have no overlap, and ±4.94 wt% SiO2 when CADA is used. Uncorrected Earth-Mars spectral differences are likely to cause errors with the same order of magnitude. As with other types of reflectance spectroscopy, Raman data are plagued by differences among single crystal/powder samples and laser wavelength that affect peak intensities, and by spectral offsets from instruments with varying resolution and wavenumber alignment schemes. These problems persist even within the archetypal RRUFF database. Pre-processing transformation functions such as optimized baseline removal

  7. Magnetic dynamos in accreting planetary bodies

    Science.gov (United States)

    Golabek, Gregor; Labrosse, Stéphane; Gerya, Taras; Morishima, Ryuji; Tackley, Paul

    2013-04-01

    Laboratory measurements revealed ancient remanent magnetization in meteorites [1] indicating the activity of magnetic dynamos in the corresponding meteorite parent body. To study under which circumstances dynamo activity is possible, we use a new methodology to simulate the internal evolution of a planetary body during accretion and differentiation. Using the N-body code PKDGRAV [2] we simulate the accretion of planetary embryos from an initial annulus of several thousand planetesimals. The growth history of the largest resulting planetary embryo is used as an input for the thermomechanical 2D code I2ELVIS [3]. The thermomechanical model takes recent parametrizations of impact processes [4] and of the magnetic dynamo [5] into account. It was pointed out that impacts can not only deposit heat deep into the target body, which is later buried by ejecta of further impacts [6], but also that impacts expose in the crater region originally deep-seated layers, thus cooling the interior [7]. This combination of impact effects becomes even more important when we consider that planetesimals of all masses contribute to planetary accretion. This leads occasionally to collisions between bodies with large ratios between impactor and target mass. Thus, all these processes can be expected to have a profound effect on the thermal evolution during the epoch of planetary accretion and may have implications for the magnetic dynamo activity. Results show that late-formed planetesimals do not experience silicate melting and avoid thermal alteration, whereas in early-formed bodies accretion and iron core growth occur almost simultaneously and a highly variable magnetic dynamo can operate in the interior of these bodies. [1] Weiss, B.P. et al., Science, 322, 713-716, 2008. [2] Richardson, D. C. et al., Icarus, 143, 45-59, 2000. [3] Gerya, T.V and Yuen, D.J., Phys. Earth Planet. Int., 163, 83-105, 2007. [4] Monteux, J. et al., Geophys. Res. Lett., 34, L24201, 2007. [5] Aubert, J. et al

  8. Thermal Infrared Spectra of a Suite of Forsterite Samples and Ab-initio Modelling of theirs Spectra

    Science.gov (United States)

    Maturilli, A.; Stangarone, C.; Helbert, J.; Tribaudino, M.; Prencipe, M.

    2017-12-01

    Forsterite is the dominating component in olivine, a major constituent in ultrafemic rocks, as well as planetary bodies. Messenger X-ray spectrometer has shown that Mg-rich silicate minerals, such as enstatite and forsterite, dominate Mercury's surface (Weider et al 2012). A careful and detailed acquaintance with the forsterite spectral features and their dependence wrt environmental conditions on Mercury is needed to interpret the remote sensing data from previous and forthcoming missions. We propose an experimental vs calculation approach to reproduce and describe the spectral features of forsterite. TIR emissivity measurements are performed by the Planetary Spectroscopy Laboratory (PSL) of DLR. PSL offers the unique capability to measure the emissivity of samples at temperature up to 1000K under vacuum conditions. TIR emissivity and reflectance measurements are performed on 11 olivine samples having a different composition within the forsterite-fayalite series. When available, the sample has been measured in 2 different grain sizes (chameleon-like effects of Mercury surface already observed (Helbert et al. 2013), this study wants to point out the main spectral features due to the composition and temperature. Our results are used to create a theoretical background to interpret the high temperature infrared emissivity spectra from MERTIS onboard the ESA BepiColombo mission to Mercury (Helbert et al. 2010).

  9. Planetary Magnetic Fields: Planetary Interiors and Habitability W. M. Keck Institute for Space Studies Report

    Science.gov (United States)

    Lazio, T. Joseph; Shkolnik, Evgenya; Hallinan, Gregg

    2017-05-01

    The W. M. Keck Institute for Space Studies (KISS) sponsored the "Planetary Magnetic Fields: Planetary Interiors and Habitability" study to review the state of knowledge of extrasolar planetary magnetic fields and the prospects for their detection.There were multiple motivations for this Study. Planetary-scale magnetic fields are a window to a planet's interior and provide shielding of the planet's atmosphere. The Earth, Mercury, Ganymede, and the giant planets of the solar system all contain internal dynamo currents that generate planetary-scale magnetic fields. In turn, these internal dynamo currents arise from differential rotation, convection, compositional dynamics, or a combination of these in objects' interiors. If coupled to an energy source, such as the incident kinetic or magnetic energy from the solar wind or an orbiting satellite, a planet's magnetic field can produce intense electron cyclotron masers in its magnetic polar regions. The most well known example of this process in the solar system is the Jovian decametric emission, but all of the giant planets and the Earth contain similar electron cyclotron masers within their magnetospheres. Extrapolated to extrasolar planets, the remote detection of the magnetic field of an extrasolar planet would provide a means of obtaining constraints on the thermal state, composition, and dynamics of its interior--all of which will be difficult to determine by other means--as well as improved understanding of the basic planetary dynamo process.We review the findings from the Study, including potential mission concepts that emerged and recent developments toward one of the mission concepts, a space-based radio wavelength array. There was an identification of that radio wavelength observations would likely be key to making significant progress in this field.We acknowledge ideas and advice from the participants in the "Planetary Magnetic Fields: Planetary Interiors and Habitability" study organized by the W. M. Keck

  10. The Planetary Data System - A solution to data management for the planetary science community

    Science.gov (United States)

    Dobinson, Elaine R.

    1990-01-01

    An overview of the first release of the Planetary Data System (PDS) is presented, and some of the challenges encountered during development of the system are described. The principal goals of the PDS are to distribute planetary science data and information about these data to NASA, to provide scientific knowledge to users of these data, and to provide for permanent storage. The current architecture and capabilities of the PDS (Version 1.0) are examined, and some of the special challenges encountered and lessons learned during the application are highlighted. Finally, implications for future versions of the PDS as well as for other science data systems are discussed.

  11. Engaging students in astronomy and spectroscopy through Project SPECTRA!

    Science.gov (United States)

    Wood, E. L.

    2011-12-01

    Computer simulations for minds-on learning with "Project Spectra!" How do we gain information about the Sun? How do we know Mars has CO2 or that Enceladus has H2O geysers? How do we use light in astronomy? These concepts are something students and educators struggle with because they are abstract. Using simulations and computer interactives (games) where students experience and manipulate the information makes concepts accessible. Visualizing lessons with multi-media solidifies understanding and retention of knowledge and is completely unlike its paper-and-pencil counterpart. Visualizations also enable teachers to forgo purchasing expensive laboratory equipment. "Project Spectra!" is a science and engineering program that uses computer-based Flash interactives to expose students to astronomical spectroscopy and actual data in a way that is not possible with traditional in-class activities. To engage students in "Project Spectra!", students are given a mission, which connects them with the research at hand. Missions range from exploring remote planetary atmospheres and surfaces, experimenting with the Sun using different filters, or analyzing the soil of a remote planet. Additionally, students have an opportunity to learn about NASA missions, view movies, and see images connected with their mission, which is something that is not practical to do during a typical paper-and-pencil activity. Since students can choose what to watch and explore, the interactives accommodate a broad range of learning styles. Students can go back and forth through the interactives if they've missed a concept or wish to view something again. In the end, students are asked critical thinking questions and conduct web-based research. These interactives complement in-class Project SPECTRA! activities exploring applications of the electromagnetic spectrum.

  12. Observing the Spectra of MEarth and TRAPPIST Planets with JWST

    Science.gov (United States)

    Morley, Caroline; Kreidberg, Laura; Rustamkulov, Zafar; Robinson, Tyler D.; Fortney, Jonathan J.

    2017-10-01

    During the past two years, nine planets close to Earth in radius have been discovered around nearby M dwarfs cooler than 3300 K. These planets include the 7 planets in the TRAPPIST-1 system and two planets discovered by the MEarth survey, GJ 1132b and LHS 1140b (Dittmann et al. 2017; Berta-Thompson et al. 2015; Gillon et al. 2017). These planets are the smallest planets discovered to date that will be amenable to atmospheric characterization with JWST. They span equilibrium temperatures from ˜130 K to >500 K, and radii from 0.7 to 1.43 Earth radii. Some of these planets orbit as distances potentially amenable to surface liquid water, though the actual surface temperatures will depend strongly on the albedo of the planet and the thickness and composition of its atmosphere. The stars they orbit also vary in activity levels, from the quiet LHS 1140b host star to the more active TRAPPIST-1 host star. This set of planets will form the testbed for our first chance to study the diversity of atmospheres around Earth-sized planets. Here, we will present model spectra of these 9 planets, varying the composition and the surface pressure of the atmosphere. We base our elemental compositions on three outcomes of planetary atmosphere evolution in our own solar system: Earth, Titan, and Venus. We calculate the molecular compositions in chemical equilibrium. We present both thermal emission spectra and transmission spectra for each of these objects, and make predictions for the observability of these spectra with different instrument modes with JWST.

  13. Planetary rovers robotic exploration of the solar system

    CERN Document Server

    Ellery, Alex

    2016-01-01

    The increasing adoption of terrain mobility – planetary rovers – for the investigation of planetary surfaces emphasises their central importance in space exploration. This imposes a completely new set of technologies and methodologies to the design of such spacecraft – and planetary rovers are indeed, first and foremost, spacecraft. This introduces vehicle engineering, mechatronics, robotics, artificial intelligence and associated technologies to the spacecraft engineer’s repertoire of skills. Planetary Rovers is the only book that comprehensively covers these aspects of planetary rover engineering and more. The book: • discusses relevant planetary environments to rover missions, stressing the Moon and Mars; • includes a brief survey of previous rover missions; • covers rover mobility, traction and control systems; • stresses the importance of robotic vision in rovers for both navigation and science; • comprehensively covers autonomous navigation, path planning and multi-rover formations on ...

  14. ESA's Planetary Science Archive: Status and Plans

    Science.gov (United States)

    Heather, David; Barthelemy, Maud; Manaud, Nicolas; Martinez, Santa; Szumlas, Marek; Vazquez, Jose Luis; Arviset, Christophe; Osuna, Pedro; PSA Development Team

    2013-04-01

    Scientific and engineering data from ESA's planetary missions are made accessible to the world-wide scientific community via the Planetary Science Archive (PSA). The PSA consists of online services incorporating search, preview, download, notification and delivery basket functionality. The PSA currently holds data from Mars Express, Venus Express, SMART-1, Huygens, Rosetta and Giotto, as well as several ground-based cometary observations. It will be used for archiving on ExoMars, BepiColombo and for the European contributions to Chandrayaan-1. The focus of the PSA activities is on the long-term preservation of data and knowledge from ESA's planetary missions. Scientific users can access the data online using several interfaces: - The Advanced Search Interface allows complex parameter based queries, providing the end user with a facility to complete very specific searches on meta-data and geometrical parameters. - The Map-based Interface is currently operational only for Mars Express HRSC and OMEGA data. This interface allows an end-user to specify a region-of-interest by dragging a box onto a base map of Mars. From this interface, it is possible to directly visualize query results. The Map-based and Advanced interfaces are linked and cross-compatible. If a user defines a region-of-interest in the Map-based interface, the results can be refined by entering more detailed search parameters in the Advanced interface. - The FTP Browser Interface is designed for more experienced users, and allows for direct browsing and access of the data set content through ftp-tree search. Each dataset contains documentation and calibration information in addition to the scientific or engineering data. All PSA data are prepared by the corresponding instrument teams, and are made to comply with the internationally recognized PDS standards. PSA supports the instrument teams in the full archiving process, from the definition of the data products, meta-data and product labels through to

  15. The International Planetary Data Alliance (IPDA)

    Science.gov (United States)

    Stein, Thomas; Gopala Krishna, Barla; Crichton, Daniel J.

    2016-07-01

    The International Planetary Data Alliance (IPDA) is a close association of partners with the aim of improving the quality of planetary science data and services to the end users of space based instrumentation. The specific mission of the IPDA is to facilitate global access to, and exchange of, high quality scientific data products managed across international boundaries. Ensuring proper capture, accessibility and availability of the data is the task of the individual member space agencies. The IPDA is focused on developing an international standard that allows discovery, query, access, and usage of such data across international planetary data archive systems. While trends in other areas of space science are concentrating on the sharing of science data from diverse standards and collection methods, the IPDA concentrates on promoting governing data standards that drive common methods for collecting and describing planetary science data across the international community. This approach better supports the long term goal of easing data sharing across system and agency boundaries. An initial starting point for developing such a standard will be internationalization of NASA's Planetary Data System's (PDS) PDS4 standard. The IPDA was formed in 2006 with the purpose of adopting standards and developing collaborations across agencies to ensure data is captured in common formats. It has grown to a dozen member agencies represented by a number of different groups through the IPDA Steering Committee. Member agencies include: Armenian Astronomical Society, China National Space Agency (CNSA), European Space Agency (ESA), German Aerospace Center (DLR), Indian Space Research Organization (ISRO), Italian Space Agency (ASI), Japanese Aerospace Exploration Agency (JAXA), National Air and Space Administration (NASA), National Centre for Space Studies (CNES), Space Research Institute (IKI), UAE Space Agency, and UK Space Agency. The IPDA Steering Committee oversees the execution of

  16. Automatic identification of mass spectra

    International Nuclear Information System (INIS)

    Drabloes, F.

    1992-01-01

    Several approaches to preprocessing and comparison of low resolution mass spectra have been evaluated by various test methods related to library search. It is shown that there is a clear correlation between the nature of any contamination of a spectrum, the basic principle of the transformation or distance measure, and the performance of the identification system. The identification of functionality from low resolution spectra has also been evaluated using several classification methods. It is shown that there is an upper limit to the success of this approach, but also that this can be improved significantly by using a very limited amount of additional information. 10 refs

  17. Correlation Functions and Power Spectra

    DEFF Research Database (Denmark)

    Larsen, Jan

    2006-01-01

    The present lecture note is a supplement to the textbook Digital Signal Processing by J. Proakis and D.G. Manolakis used in the IMM/DTU course 02451 Digital Signal Processing and provides an extended discussion of correlation functions and power spectra. The definitions of correlation functions....... It is possible to define correlation functions and associated spectra for aperiodic, periodic and random signals although the interpretation is different. Moreover, we will discuss correlation functions when mixing these basic signal types. In addition, the note include several examples for the purpose...

  18. Dynamics of Planetary Systems in Star Clusters

    Science.gov (United States)

    Spurzem, R.; Giersz, M.; Heggie, D. C.; Lin, D. N. C.

    2009-05-01

    At least 10%-15% of nearby Sunlike stars have known Jupiter-mass planets. In contrast, very few planets are found in mature open and globular clusters such as the Hyades and 47 Tuc. We explore here the possibility that this dichotomy is due to the postformation disruption of planetary systems associated with the stellar encounters in long-lived clusters. One supporting piece of evidence for this scenario is the discovery of freely floating low-mass objects in star forming regions. We use two independent numerical approaches, a hybrid Monte Carlo and a direct N-body method, to simulate the impact of the encounters. We show that the results of numerical simulations are in reasonable agreement with analytical determinations in the adiabatic and impulsive limits. They indicate that distant stellar encounters generally do not significantly modify the compact and nearly circular orbits. However, moderately close stellar encounters, which are likely to occur in dense clusters, can excite planets' orbital eccentricity and induce dynamical instability in systems that are closely packed with multiple planets. The disruption of planetary systems occurs primarily through occasional nearly parabolic, nonadiabatic encounters, though eccentricity of the planets evolves through repeated hyperbolic adiabatic encounters that accumulate small-amplitude changes. The detached planets are generally retained by the potential of their host clusters as free floaters in young stellar clusters such as σ Orionis. We compute effective cross sections for the dissolution of planetary systems and show that, for all initial eccentricities, dissolution occurs on timescales that are longer than the dispersion of small stellar associations, but shorter than the age of typical open and globular clusters. Although it is much more difficult to disrupt short-period planets, close encounters can excite modest eccentricity among them, such that subsequent tidal dissipation leads to orbital decay, tidal

  19. Risk to civilization: A planetary science perspective

    International Nuclear Information System (INIS)

    Chapman, C.R.; Morrison, D.

    1988-01-01

    One of the most profound changes in our perspective of the solar system resulting from the first quarter century of planetary exploration by spacecraft is the recognition that planets, including Earth, were bombarded by cosmic projectiles for 4.5 aeons and continue to be bombarded today. Although the planetary cratering rate is much lower now than it was during the first 0.5 aeons, sizeable Earth-approaching asteroids and comets continue to hit the Earth at a rate that poses a finite risk to civilization. The evolution of this planetary perspective on impact cratering is gradual over the last two decades. It took explorations of Mars and Mercury by early Mariner spacecraft and of the outer solar system by the Voyagers to reveal the significance of asteroidal and cometary impacts in shaping the morphologies and even chemical compositions of the planets. An unsettling implication of the new perspective is addressed: the risk to human civilization. Serious scientific attention was given to this issue in July 1981 at a NASA-sponsored Spacewatch Workshop in Snowmass, Colorado. The basic conclusion of the 1981 NASA sponsored workshop still stands: the risk that civilization might be destroyed by impact with an as-yet-undiscovered asteroid or comet exceeds risk levels that are sometimes deemed unacceptable by modern societies in other contexts. Yet these impact risks have gone almost undiscussed and undebated. The tentative quantitative assessment by some members of the 1981 workshop was that each year, civilization is threatened with destruction with a probability of about 1 in 100,000. The enormous spread in risk levels deemed by the public to be at the threshold of acceptability derives from a host of psychological factors that were widely discussed in the risk assessment literature

  20. Circumstellar Gas in Young Planetary Debris Disks

    Science.gov (United States)

    Roberge, A.

    Circumstellar (CS) disks orbiting young stars fall into two categories: primordial disks, composed of unprocessed interstellar dust and gas, and debris disks, produced by the destruction of solid planetary bodies. In the first class, the most abundant gas is H_2; in the second, it appears that the H_2 gas has disappeared, possibly through incorporation into gas giant planets. The lifetime of H_2 gas in a CS disk is therefore of great importance, as it dictates the timescale for the formation of giant planets. FUSE observations of H_2 in CS disk systems have shown that FUV absorption spectroscopy may sensitively probe for small amounts of gas along the line of sight to the star. Most importantly, the FUSE non-detection of H_2 gas in the Beta Pictoris disk suggests that the primordial gas lifetime is less than about 12 Myr, and that gas giant planets must form very quickly. However, this suggestion is based on one system, and needs to be tested in additional systems with a range of ages, especially since there are indications that age is not the only factor in the evolution of a CS disk. We propose for FUSE observations of 3 additional debris disk systems, Fomalhaut, HD3003, and HD2884. Fomalhaut is an intermediate age debris disk, one of the Fabulous Four CS disks first discovered in 1984. The other two disks are younger, with ages similar to that of Beta Pic. All three stars are brighter in the FUV than Beta Pic, permitting us to sensitively probe for traces of H_2 gas. We will also measure the amount of secondary atomic gas produced from planetary bodies in these disks, in an effort to understand the entire evolution of CS gas in young planetary systems.

  1. Human-Automation Collaboration: Support for Lunar and Planetary Exploration

    National Research Council Canada - National Science Library

    Marquez, Jessica J

    2007-01-01

    .... This thesis investigates the appropriate balance between humans and automation for geospatial path problem solving within the high-risk domain of human planetary surface exploration, where decisions...

  2. Robotic Tool Changer for Planetary Exploration, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Future planetary exploration missions will require compact, lightweight robotic manipulators for handling a variety of tools & instruments without increasing the...

  3. Advanced Calibration Source for Planetary and Earth Observing Imaging

    Data.gov (United States)

    National Aeronautics and Space Administration — Planetary and Earth imaging requires radiometrically calibrated and stable imaging sensors.  Radiometric calibration enables the ability to remove or mitigate...

  4. High Performance Monopropellants for Future Planetary Ascent Vehicles, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Physical Sciences Inc. proposes to design, develop, and demonstrate, a novel high performance monopropellant for application in future planetary ascent vehicles. Our...

  5. Precision Time Protocol Based Trilateration for Planetary Navigation, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's vision for planetary exploration requires development and field testing of the key technologies required for extended habitation. To support extended lunar...

  6. Advanced, Compact, Ultraviolet Imaging Spectrometer for Planetary Systems

    Data.gov (United States)

    National Aeronautics and Space Administration — The Advanced, Compact, Ultraviolet Imaging Spectrometer for Planetary Systems will advance the capabilities of ultraviolet imaging spectrometers by improving the...

  7. POLARIMETRY OF PLANETARY SATELLITES V1.0

    Data.gov (United States)

    National Aeronautics and Space Administration — This compilation of polarimetry of planetary satellites has been compiled from the published literature and from unpublished results by Zaitsev, Rosenbush, and...

  8. Planetary Simulation Chambers bring Mars to laboratory studies

    Energy Technology Data Exchange (ETDEWEB)

    Mateo-Marti, E.

    2016-07-01

    Although space missions provide fundamental and unique knowledge for planetary exploration, they are always costly and extremely time-consuming. Due to the obvious technical and economical limitations of in-situ planetary exploration, laboratory simulations are among the most feasible research options for making advances in planetary exploration. Therefore, laboratory simulations of planetary environments are a necessary and complementary option to expensive space missions. Simulation chambers are economical, more versatile, and allow for a higher number of experiments than space missions. Laboratory-based facilities are able to mimic the conditions found in the atmospheres and on the surfaces of a majority of planetary objects. Number of relevant applications in Mars planetary exploration will be described in order to provide an understanding about the potential and flexibility of planetary simulation chambers systems: mainly, stability and presence of certain minerals on Mars surface; and microorganisms potential habitability under planetary environmental conditions would be studied. Therefore, simulation chambers will be a promising tools and necessary platform to design future planetary space mission and to validate in-situ measurements from orbital or rover observations. (Author)

  9. Influence of stellar duplicity on the form of planetary nebulae

    International Nuclear Information System (INIS)

    Kolesnik, I.G.; Pilyugin, L.S.

    1986-01-01

    Formation of planetary nebulae's spatial structures is considered. Simple expression for angular distribution of density in planetary nebulae is obtained. Bipolar structures are formed effectively in binary systems in which the velocity of the expanding shell around the main star is smaller than the orbital velocity of the satellite. Masses of satellites lie in the range 0.1-0.4Msub(sun). Theoretical isophotal contour map for the model of the planetary nebula NGC 3587 is consistent with observational data. It is shown that central stars of planetary nebulae are usually binary systems

  10. The current research of planetary nebulae distance measurement

    Science.gov (United States)

    Yang, Yuan-yuan; Zhu, Hui; Tian, Wen-wu; Wu, Dan

    2015-08-01

    Planetary Nebula is an important tracer of Galactic chemical history and evolution, star and interstellar evolution. Distance as a basic physical parameter of planetary nebula, is crucial to study its size, luminosity, ionized mass, formation rate, space density and Galactic distribution. Distance of planetary nebula has been studied for several decades, but most of their distances are not well determined, e.g. only thirty-one planetary nebulae have distance measurement with uncertainty within 20%. We summarize major distance measurement methods of planetary nebulae, i.e., trigonometric parallax, cluster member, expansion parallax, spectroscopic parallax, reddening, Na D absorption, determinations of central star gravities, Shklovsky method, kinematics method, and then discuss the limitations and applications scope of each method in detail. Actually, applying different methods to the same planetary nebulae can have a huge difference in distance, and even the same method can lead to great difference for the same planetary nebula. We focus on the kinematics method applied to planetary nebulae either seriously effected by Galactic extinction or having no observable centra star but being radio bright. The kinematics distance has been used in our on-going project of radio planetary nebulae distance measurement.

  11. Simultaneous Localization and Mapping for Planetary Surface Mobility, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — ProtoInnovations, LLC and Carnegie Mellon University have formed a partnership to commercially develop localization and mapping technologies for planetary rovers....

  12. Chemistry of Planetary Atmospheres: Insights and Prospects

    Science.gov (United States)

    Yung, Yuk

    2015-11-01

    Using observations from the Mariners, Pioneers, Vikings, Voyagers, Pioneer Venus, Galileo, Venus Express, Curiosity, Cassini, New Horizons, and numerous observatories both in orbit of Earth and on the ground, I will give a survey of the major chemical processes that control the composition of planetary atmospheres. For the first time since the beginning of the space age, we understand the chemistry of planetary atmospheres ranging from the primitive atmospheres of the giant planets to the highly evolved atmospheres of terrestrial planets and small bodies. Our understanding can be distilled into three important ideas: (1) The stability of planetary atmospheres against escape of their constituents to space, (2) the role of equilibrium chemistry in determining the partitioning of chemical species, and (3) the role of disequilibrium chemistry, which produces drastic departures from equilibrium chemistry. To these three ideas we must also add a fourth: the role of biochemistry at Earth's surface, which makes its atmospheric chemistry unique in the cosmochemical environment. Only in the Earth's atmosphere do strong reducing and oxidizing species coexist to such a degree. For example, nitrogen species in the Earth's atmosphere span eight oxidation states from ammonia to nitric acid. Much of the Earth's atmospheric chemistry consists of reactions initiated by the degradation of biologically produced molecules. Life uses solar energy to drive chemical reactions that would otherwise not occur; it represents a kind of photochemistry that is special to Earth, at least within the Solar System. It remains to be seen how many worlds like Earth there are beyond the Solar System, especially as we are now exploring the exoplanets using Kepler, TESS, HST, Spitzer, soon to be launched missions such as JWST and WFIRST, and ground-based telescopes. The atmospheres of the Solar System provide a benchmark for studying exoplanets, which in turn serve to test and extend our current

  13. A Planetary System with an Escaping Mars

    OpenAIRE

    Süli, Áron; Dvorak, Rudolf

    2005-01-01

    The chaotic behaviour of the motion of the planets in our Solar System is well established. In this work to model a hypothetical extrasolar planetary system our Solar System was modified in such a way that we replaced the Earth by a more massive planet and let the other planets and all the orbital elements unchanged. The major result of former numerical experiments with a modified Solar System was the appearance of a chaotic window at $\\kappa_E \\in (4,6)$, where the dynamical state of the sys...

  14. Magnetometer for measuring planetary magnetic fields

    DEFF Research Database (Denmark)

    Merayo, José M.G.; Brauer, Peter

    . The mass, power and volume are important factors when designing planetary magnetometers. However, the performance must not be compromised. The DTU magnetometer consisting of a triaxial fluxgate sensor and controlling electronics is a miniaturized version of the instruments flown on the Oersted, Astrid-2......, CHAMP and SAC-C missions. It can produce vector measurements at a rate of 50 Hz and with a precision of more than 21 bits. The thermal and long term stability of the instrument is less than 0.5 nT. The power consumption of the instrument is less than 0.5W for continuous operation. For an orbiting...

  15. Planetary maps - Passports for the mind

    International Nuclear Information System (INIS)

    Anderson, C.M.

    1990-01-01

    The various types of planetary maps are reviewed. Included are basic descriptions of planimetric, topographic, geologic, and digital maps. It is noted that planimetric maps are pictorial representations of a planet's round surface flattened into a plane, such as controlled photomosaic maps and shaded relief maps. Topographic maps, those usually made with data from altimeters and stereoscopic images, have contour lines indicating the shapes and elevations of landforms. Geologic maps carry additional information about landforms, such as rock types, the processes that formed them, and their relative ages. The International Astronomical Union nomenclature system is briefly discussed, pointing out that the Union often assigns themes to areas to be mapped

  16. Instrumented Moles for Planetary Subsurface Regolith Studies

    Science.gov (United States)

    Richter, L. O.; Coste, P. A.; Grzesik, A.; Knollenberg, J.; Magnani, P.; Nadalini, R.; Re, E.; Romstedt, J.; Sohl, F.; Spohn, T.

    2006-12-01

    Soil-like materials, or regolith, on solar system objects provide a record of physical and/or chemical weathering processes on the object in question and as such possess significant scientific relevance for study by landed planetary missions. In the case of Mars, a complex interplay has been at work between impact gardening, aeolian as well as possibly fluvial processes. This resulted in regolith that is texturally as well as compositionally layered as hinted at by results from the Mars Exploration Rover (MER) missions which are capable of accessing shallow subsurface soils by wheel trenching. Significant subsurface soil access on Mars, i.e. to depths of a meter or more, remains to be accomplished on future missions. This has been one of the objectives of the unsuccessful Beagle 2 landed element of the ESA Mars Express mission having been equipped with the Planetary Underground Tool (PLUTO) subsurface soil sampling Mole system capable of self-penetration into regolith due to an internal electro-mechanical hammering mechanism. This lightweight device of less than 900 g mass was designed to repeatedly obtain and deliver to the lander regolith samples from depths down to 2 m which would have been analysed for organic matter and, specifically, organic carbon from potential extinct microbial activity. With funding from the ESA technology programme, an evolved Mole system - the Instrumented Mole System (IMS) - has now been developed to a readiness level of TRL 6. The IMS is to serve as a carrier for in situ instruments for measurements in planetary subsurface soils. This could complement or even eliminate the need to recover samples to the surface. The Engineering Model hardware having been developed within this effort is designed for accommodating a geophysical instrument package (Heat Flow and Physical Properties Package, HP3) that would be capable of measuring regolith physical properties and planetary heat flow. The chosen design encompasses a two-body Mole

  17. Planetary nebulae and the interstellar medium

    Science.gov (United States)

    Aller, L. H.

    1986-01-01

    In addition to available published data on planetary nebulae (PN), some 40 objects largely concentrated towards the galactic center and anticenter regions were included. All were observed with the Lick 3(sup m) telescope and image tube scanner. Abundances of C, N, O, Ne, Cl, and Ar were determined by a procedure in which theoretical models were used to obtain ionization correction factors (ICF). Of the 106 PN, 66 are N-rich and 40 are N-poor. There appear to be no significant differences between the average compositions in the solar neighborhood and the average taken over the entire observable portion of the galaxy.

  18. NASA Lunar and Planetary Mapping and Modeling

    Science.gov (United States)

    Day, B. H.; Law, E.

    2016-12-01

    NASA's Lunar and Planetary Mapping and Modeling Portals provide web-based suites of interactive visualization and analysis tools to enable mission planners, planetary scientists, students, and the general public to access mapped lunar data products from past and current missions for the Moon, Mars, and Vesta. New portals for additional planetary bodies are being planned. This presentation will recap significant enhancements to these toolsets during the past year and look forward to the results of the exciting work currently being undertaken. Additional data products and tools continue to be added to the Lunar Mapping and Modeling Portal (LMMP). These include both generalized products as well as polar data products specifically targeting potential sites for the Resource Prospector mission. Current development work on LMMP also includes facilitating mission planning and data management for lunar CubeSat missions, and working with the NASA Astromaterials Acquisition and Curation Office's Lunar Apollo Sample database in order to help better visualize the geographic contexts from which samples were retrieved. A new user interface provides, among other improvements, significantly enhanced 3D visualizations and navigation. Mars Trek, the project's Mars portal, has now been assigned by NASA's Planetary Science Division to support site selection and analysis for the Mars 2020 Rover mission as well as for the Mars Human Landing Exploration Zone Sites. This effort is concentrating on enhancing Mars Trek with data products and analysis tools specifically requested by the proposing teams for the various sites. Also being given very high priority by NASA Headquarters is Mars Trek's use as a means to directly involve the public in these upcoming missions, letting them explore the areas the agency is focusing upon, understand what makes these sites so fascinating, follow the selection process, and get caught up in the excitement of exploring Mars. The portals also serve as

  19. Automatic extraction of planetary image features

    Science.gov (United States)

    LeMoigne-Stewart, Jacqueline J. (Inventor); Troglio, Giulia (Inventor); Benediktsson, Jon A. (Inventor); Serpico, Sebastiano B. (Inventor); Moser, Gabriele (Inventor)

    2013-01-01

    A method for the extraction of Lunar data and/or planetary features is provided. The feature extraction method can include one or more image processing techniques, including, but not limited to, a watershed segmentation and/or the generalized Hough Transform. According to some embodiments, the feature extraction method can include extracting features, such as, small rocks. According to some embodiments, small rocks can be extracted by applying a watershed segmentation algorithm to the Canny gradient. According to some embodiments, applying a watershed segmentation algorithm to the Canny gradient can allow regions that appear as close contours in the gradient to be segmented.

  20. Circumnebular neutral hydrogen in planetary nebulae

    International Nuclear Information System (INIS)

    Taylor, A.R.; Gussie, G.T.; Pottasch, S.R.

    1990-01-01

    Centimeter line observations of six compact planetary nebulae are reported. Circumnebular atomic hydrogen absorption has been observed in NGC 6790, NGC 6886, IC 418, IC 5117, and BD +30 deg 3639, while H I was not observed to a high upper limit in NGC 6741. Hydrogen was also detected in emission from BD +30 deg 3639. The expansion velocities of the circumnebular envelopes are similar to the expansion velocities observed for the ionized nebula. The optical depth of circumnebular H I appears to decrease with increasing linear radius of the ionized nebulae, indicating that these nebulae are ionization bounded and that the amount of atomic hydrogen decreases as young nebulas evolve. 28 refs

  1. Strategy of Planetary Data Archives in Japanese Missions for Planetary Data System

    Science.gov (United States)

    Yamamoto, Y.; Ishihara, Y.; Murakami, S. Y.

    2017-12-01

    To preserve data acquired by Japanese planetary explorations for a long time, we need a data archiving strategy in a form suitable for resources. Planetary Data System(PDS) developed by NASA is an excellent system for saving data over a long period. Especially for the current version 4 (PDS4), it is possible to create a data archive with high completeness using information technology. Historically, the Japanese planetary missions have archived data by scientists in their ways, but in the past decade, JAXA has been aiming to conform data to PDS considering long term preservation. Hayabusa, Akatsuki are archived in PDS3. Kaguya(SELENE) data have been newly converted from the original format to PDS3. Hayabusa2 and BepiColombo, and future planetary explorations will release data in PDS4. The cooperation of engineers who are familiar with information technology is indispensable to create data archives for scientists. In addition, it is essential to have experience, information sharing, and a system to support it. There is a challenge in Japan about the system.

  2. Fluorescence Spectra of Highlighter Inks

    Science.gov (United States)

    Birriel, Jennifer J.; King, Damon

    2018-01-01

    Fluorescence spectra excited by laser pointers have been the subject of several papers in "TPT". These papers all describe a fluorescence phenomenon in which the reflected laser light undergoes a change in color: this color change results from the combination of some partially reflected laser light and additional colors generated by…

  3. Classical Trajectories and Quantum Spectra

    Science.gov (United States)

    Mielnik, Bogdan; Reyes, Marco A.

    1996-01-01

    A classical model of the Schrodinger's wave packet is considered. The problem of finding the energy levels corresponds to a classical manipulation game. It leads to an approximate but non-perturbative method of finding the eigenvalues, exploring the bifurcations of classical trajectories. The role of squeezing turns out decisive in the generation of the discrete spectra.

  4. Explanation of earthquake response spectra

    OpenAIRE

    Douglas, John

    2017-01-01

    This is a set of five slides explaining how earthquake response spectra are derived from strong-motion records and simple models of structures and their purpose within seismic design and assessment. It dates from about 2002 and I have used it in various introductory lectures on engineering seismology.

  5. Spectrophotometry near the atmospheric cutoff of the strongest Bowen resonance fluorescence lines of O III in two planetary nebulae

    Science.gov (United States)

    O'Dell, C. R.; Opal, Chet B.

    1989-01-01

    Spectrophotometric results are presented for the stronger, well-resolved Bowen O III resonance fluorescence emission lines in the planetary nebulae 7027 and NGC 7662 down to and including the intrinsically strong line at 3133 A. These data are combined with results from the IUE atlas of spectra and similar results for the longer wavelength lines by Likkel and Aller (1986) to give the first full coverage of the Bowen lines. Good agreement is found with fluorescence theory for the primary cascade lines, except for the Likkel and Aller results. The efficiency of conversion of the exciting He II Ly-alpha into O III lines is determined, and values comparable to other planetary nebulae are found.

  6. Planetary Torque in 3D Isentropic Disks

    Energy Technology Data Exchange (ETDEWEB)

    Fung, Jeffrey [Department of Astronomy, University of California at Berkeley, Campbell Hall, Berkeley, CA 94720-3411 (United States); Masset, Frédéric; Velasco, David [Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Av. Universidad s/n, 62210 Cuernavaca, Mor. (Mexico); Lega, Elena, E-mail: jeffrey.fung@berkeley.edu [Université de la Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange UMR 7293, Nice (France)

    2017-03-01

    Planetary migration is inherently a three-dimensional (3D) problem, because Earth-size planetary cores are deeply embedded in protoplanetary disks. Simulations of these 3D disks remain challenging due to the steep resolution requirements. Using two different hydrodynamics codes, FARGO3D and PEnGUIn, we simulate disk–planet interaction for a one to five Earth-mass planet embedded in an isentropic disk. We measure the torque on the planet and ensure that the measurements are converged both in resolution and between the two codes. We find that the torque is independent of the smoothing length of the planet’s potential ( r {sub s}), and that it has a weak dependence on the adiabatic index of the gaseous disk ( γ ). The torque values correspond to an inward migration rate qualitatively similar to previous linear calculations. We perform additional simulations with explicit radiative transfer using FARGOCA, and again find agreement between 3D simulations and existing torque formulae. We also present the flow pattern around the planets that show active flow is present within the planet’s Hill sphere, and meridional vortices are shed downstream. The vertical flow speed near the planet is faster for a smaller r {sub s} or γ , up to supersonic speeds for the smallest r {sub s} and γ in our study.

  7. Gender Diversity in Planetary Volcanology: Encouraging Equality

    Science.gov (United States)

    Gregg, T. K.; Lopes, R. M.

    2004-12-01

    We have brought together a group of respected and well-known female planetary volcanologists to create a book designed to encourage young women to pursue scientific careers. The book, entitled "Volcanic Worlds: Exploring the Solar System's Volcanoes," published by Praxis, is written for undergraduates who may have no background in geology or planetary sciences. Each chapter covers a different Solar System body or volcanic process, and is authored by a woman who is an expert in her field. Subjects covered include: the relation of plate tectonics to volcanism on Earth; the study of Mars' volcanoes from space and using rovers; geysers on Neptune's moon Triton and on Earth; eruptions on Io; and studying submarine lava flows from a submarine. Each chapter is written in a comfortable, readily accessible tone, with authors presenting not only science, but also some of the unique challenges faced by women conducting volcanological research today-and how these are overcome. Although not intended to be a textbook, this work could easily form the basis of an undergraduate geology seminar, honors course, or as a valuable accessory to an introductory geology course. In addition, it could be used in courses that would be cross-listed between geology departments and sociology departments. We will present more information on the book, and suggestions of how it could be used in the classroom to enhance gender diversity in the Earth and Space Sciences.

  8. Using Vulcan to Recreate Planetary Cores

    CERN Document Server

    Collins, G W; Benedetti, L R; Benuzzi-Mounaix, A; Cauble, R; Celliers, P M; Danson, C; Da Silva, L B; Gessner, H; Henry, E; Hicks, D G; Huser, G; Jeanloz, R; Koening, M; Lee, K M; Mackinnon, A J; Moon, S J; Neely, D; Notley, M; Pasley, J; Willi, O

    2001-01-01

    An accurate equation of state (EOS) for planetary constituents at extreme conditions is the key to any credible model of planets or low mass stars. However, experimental validation has been carried out on at high pressure (>few Mbar), and then only on the principal Hugoniot. For planetary and stellar interiors, compression occurs from gravitational force so that material states follow a line of isentropic compression (ignoring phase separation) to ultra-high densities. An example of the predicted states for water along the isentrope for Neptune is shown in a figure. The cutaway figure on the left is from Hubbard, and the phase diagram on the right is from Cavazzoni et al. Clearly these states lie at quite a bit lower temperature and higher density than single shock Hugoniot states but they are at higher temperature than can be achieved with accurate diamond anvil experiments. At extreme densities, material states are predicted to have quite unearthly properties such as high temperature superconductivity and l...

  9. H3+ cooling in planetary atmospheres.

    Science.gov (United States)

    Miller, Steve; Stallard, Tom; Melin, Henrik; Tennyson, Jonathan

    2010-01-01

    We review the role of H3+ in planetary atmospheres, with a particular emphasis on its effect in cooling and stabilising, an effect that has been termed the "H3+ thermostat" (see Miller et al., Philos. Trans. R. Soc. London, Ser. A, 2000, 58, 2485). In the course of our analysis of this effect, we found that cooling functions that make use of the partition function, Q(T) based on the calculated H3+ energy levels of Neale and Tennyson (Astrophys. J., 1995, 454, L169) may underestimate just how much energy this ion is radiating to space. So we present a new fit to the calculated values of Q(T) that is accurate to within 2% for the range 100 K to 10 000 K, a very significant improvement on the fit originally provided by Neale and Tennyson themselves. We also present a fit to Q(T) calculated from only those values Neale and Tennyson computed from first principles, which may be more appropriate for planetary scientists wishing to calculate the amount of atmospheric cooling from the H3+ ion.

  10. of Planetary Nebulae III. NGC 6781

    Directory of Open Access Journals (Sweden)

    Hugo E. Schwarz

    2006-01-01

    Full Text Available Continuing our series of papers on the three-dimensional (3D structures and accurate distances to Planetary Nebulae (PNe, we present our study of the planetary nebula NGC6781. For this object we construct a 3D photoionization model and, using the constraints provided by observational data from the literature we determine the detailed 3D structure of the nebula, the physical parameters of the ionizing source and the first precise distance. The procedure consists in simultaneously fitting all the observed emission line morphologies, integrated intensities and the two-dimensional (2D density map from the [SII] (sulfur II line ratios to the parameters generated by the model, and in an iterative way obtain the best fit for the central star parameters and the distance to NGC6781, obtaining values of 950±143 pc (parsec – astronomic distance unit and 385 LΘ (solar luminosity for the distance and luminosity of the central star respectively. Using theoretical evolutionary tracks of intermediate and low mass stars, we derive the mass of the central star of NGC6781 and its progenitor to be 0.60±0.03MΘ (solar mass and 1.5±0.5MΘ respectively.

  11. Planetary Torque in 3D Isentropic Disks

    International Nuclear Information System (INIS)

    Fung, Jeffrey; Masset, Frédéric; Velasco, David; Lega, Elena

    2017-01-01

    Planetary migration is inherently a three-dimensional (3D) problem, because Earth-size planetary cores are deeply embedded in protoplanetary disks. Simulations of these 3D disks remain challenging due to the steep resolution requirements. Using two different hydrodynamics codes, FARGO3D and PEnGUIn, we simulate disk–planet interaction for a one to five Earth-mass planet embedded in an isentropic disk. We measure the torque on the planet and ensure that the measurements are converged both in resolution and between the two codes. We find that the torque is independent of the smoothing length of the planet’s potential ( r s ), and that it has a weak dependence on the adiabatic index of the gaseous disk ( γ ). The torque values correspond to an inward migration rate qualitatively similar to previous linear calculations. We perform additional simulations with explicit radiative transfer using FARGOCA, and again find agreement between 3D simulations and existing torque formulae. We also present the flow pattern around the planets that show active flow is present within the planet’s Hill sphere, and meridional vortices are shed downstream. The vertical flow speed near the planet is faster for a smaller r s or γ , up to supersonic speeds for the smallest r s and γ in our study.

  12. An urban approach to planetary boundaries.

    Science.gov (United States)

    Hoornweg, Daniel; Hosseini, Mehdi; Kennedy, Christopher; Behdadi, Azin

    2016-09-01

    The achievement of global sustainable development goals subject to planetary boundaries will mostly be determined by cities as they drive cultures, economies, material use, and waste generation. Locally relevant, applied and quantitative methodologies are critical to capture the complexity of urban infrastructure systems, global inter-connections, and to monitor local and global progress toward sustainability. An urban monitoring (and communications) tool is presented here illustrating that a city-based approach to sustainable development is possible. Following efforts to define and quantify safe planetary boundaries in areas such as climate change, biosphere integrity, and freshwater use, this paper modifies the methodology to propose boundaries from a city's perspective. Socio-economic boundaries, or targets, largely derived from the Sustainable Development Goals are added to bio-physical boundaries. Issues such as data availability, city priorities, and ease of implementation are considered. The framework is trialed for Toronto, Shanghai, Sao Paulo, Mumbai, and Dakar, as well as aggregated for the world's larger cities. The methodology provides an important tool for cities to play a more fulsome and active role in global sustainable development.

  13. Planetary Systems and the Origins of Life

    Science.gov (United States)

    Pudritz, Ralph; Higgs, Paul; Stone, Jonathon

    2013-01-01

    Preface; Part I. Planetary Systems and the Origins of Life: 1. Observations of extrasolar planetary systems Shay Zucker; 2. The atmospheres of extrasolar planets L. Jeremy Richardson and Sara Seager; 3. Terrestrial planet formation Edward Thommes; 4. Protoplanetary disks, amino acids and the genetic code Paul Higgs and Ralph Pudritz; 5. Emergent phenomena in biology: the origin of cellular life David Deamer; Part II. Life on Earth: 6. Extremophiles: defining the envelope for the search for life in the Universe Lynn Rothschild; 7. Hyperthermophilic life on Earth - and on Mars? Karl Stetter; 8. Phylogenomics: how far back in the past can we go? Henner Brinkmann, Denis Baurain and Hervé Philippe; 9. Horizontal gene transfer, gene histories and the root of the tree of life Olga Zhaxybayeva and J. Peter Gogarten; 10. Evolutionary innovation versus ecological incumbency Adolf Seilacher; 11. Gradual origins for the Metazoans Alexandra Pontefract and Jonathan Stone; Part III. Life in the Solar System?: 12. The search for life on Mars Chris McKay; 13. Life in the dark dune spots of Mars: a testable hypothesis Eörs Szathmary, Tibor Ganti, Tamas Pocs, Andras Horvath, Akos Kereszturi, Szaniszlo Berzci and Andras Sik; 14. Titan: a new astrobiological vision from the Cassini-Huygens data François Raulin; 15. Europa, the Ocean Moon: tides, permeable ice, and life Richard Greenberg; Index.

  14. Organic materials in planetary and protoplanetary systems: nature or nurture?

    Science.gov (United States)

    Dalle Ore, C. M.; Fulchignoni, M.; Cruikshank, D. P.; Barucci, M. A.; Brunetto, R.; Campins, H.; de Bergh, C.; Debes, J. H.; Dotto, E.; Emery, J. P.; Grundy, W. M.; Jones, A. P.; Mennella, V.; Orthous-Daunay, F. R.; Owen, T.; Pascucci, I.; Pendleton, Y. J.; Pinilla-Alonso, N.; Quirico, E.; Strazzulla, G.

    2011-09-01

    Aims: The objective of this work is to summarize the discussion of a workshop aimed at investigating the properties, origins, and evolution of the materials that are responsible for the red coloration of the small objects in the outer parts of the solar system. Because of limitations or inconsistencies in the observations and, until recently, the limited availability of laboratory data, there are still many questions on the subject. Our goal is to approach two of the main questions in a systematic way: - Is coloring an original signature of materials that are presolar in origin ("nature") or stems from post-formational chemical alteration, or weathering ("nurture")? - What is the chemical signature of the material that causes spectra to be sloped towards the red in the visible? We examine evidence available both from the laboratory and from observations sampling different parts of the solar system and circumstellar regions (disks). Methods: We present a compilation of brief summaries gathered during the workshop and describe the evidence towards a primordial vs. evolutionary origin for the material that reddens the small objects in the outer parts of our, as well as in other, planetary systems. We proceed by first summarizing laboratory results followed by observational data collected at various distances from the Sun. Results: While laboratory experiments show clear evidence of irradiation effects, particularly from ion bombardment, the first obstacle often resides in the ability to unequivocally identify the organic material in the observations. The lack of extended spectral data of good quality and resolution is at the base of this problem. Furthermore, that both mechanisms, weathering and presolar, act on the icy materials in a spectroscopically indistinguishable way makes our goal of defining the impact of each mechanism challenging. Conclusions: Through a review of some of the workshop presentations and discussions, encompassing laboratory experiments as well

  15. Spectral atlas for amateur astronomers a guide to the spectra of astronomical objects and terrestrial light sources

    CERN Document Server

    Walker, Richard

    2017-01-01

    Featuring detailed commented spectral profiles of more than one hundred astronomical objects, in colour, this spectral guide documents most of the important and spectroscopically observable objects accessible using typical amateur equipment. It allows you to read and interpret the recorded spectra of the main stellar classes, as well as most of the steps from protostars through to the final stages of stellar evolution as planetary nebulae, white dwarfs or the different types of supernovae. It also presents integrated spectra of stellar clusters, galaxies and quasars, and the reference spectra of some terrestrial light sources, for calibration purposes. Whether used as the principal reference for comparing with your recorded spectra or for inspiring independent observing projects, this atlas provides a breathtaking view into our Universe's past. The atlas is accompanied and supplemented by Spectroscopy for Amateur Astronomers, which explains in detail the methods for recording, processing, analysing and interp...

  16. 75 FR 19661 - NASA Advisory Council; Science Committee; Planetary Protection Subcommittee; Meeting

    Science.gov (United States)

    2010-04-15

    ... includes the following topics: --Review European Space Agency-NASA Coordination on Planetary Protection... Committee; Planetary Protection Subcommittee; Meeting AGENCY: National Aeronautics and Space Administration... (NASA) announces a meeting of the Planetary Protection Subcommittee of the NASA Advisory Council (NAC...

  17. ESA's Planetary Science Archive and Associated Scientific Activity

    Science.gov (United States)

    Manaud, N.; Heather, D.; Barthelemy, M.; Martinez, S.; Vazquez, J. L.; Szumlas, M.

    2011-03-01

    The European Space Agency’s Planetary Science Archive (PSA) makes all scientific and engineering data returned by ESA’s planetary missions accessible to the world-wide scientific community. It also provides additional support for the production of scientific data.

  18. Finite Elements Contact Modelling of Planetary Gear Trains

    Science.gov (United States)

    Stoyanov, Svetlin; Dobrev, Vasko; Dobreva, Antoaneta

    2017-10-01

    The paper presents the application aspects of computer technologies concerning the process of creating theoretical contact models of planetary gear trains using Abaqus/Explicit. The necessary assumptions, constrains and specific features of these gear drives are discussed in details. The models created are appropriate and useful tools for computer simulation research of the dynamic behaviour of planetary gear trains.

  19. Analytical Solution Of Complete Schwarzschild\\'s Planetary Equation

    African Journals Online (AJOL)

    It is well known how to solve the Einstein\\'s planetary equation of motion by the method of successive approximation for the corresponding orbit solution. In this paper, we solve the complete schwarzschild\\'s planetary equation of motion by an exact analytical method. The result reveals that there are actually eight exact ...

  20. The Planetary Nebula Spectrograph : The green light for galaxy kinematics

    NARCIS (Netherlands)

    Douglas, NG; Arnaboldi, M; Freeman, KC; Kuijken, K; Merrifield, MR; Romanowsky, AJ; Taylor, K; Capaccioli, M; Axelrod, T; Gilmozzi, R; Hart, J; Bloxham, G; Jones, D

    2002-01-01

    Planetary nebulae (PNe) are now well established as probes of galaxy dynamics and as standard candles in distance determinations. Motivated by the need to improve the efficiency of planetary nebulae searches and the speed with which their radial velocities are determined, a dedicated instrument-the

  1. Significant achievements in the Planetary Geology Program, 1981

    International Nuclear Information System (INIS)

    Holt, H.E.

    1981-09-01

    Recent developments in planetology research as reported at the 1981 NASA Planetary Geology Principal Investigators meeting are summarized. The evolution of the solar system, comparative planetology, and geologic processes active on other planets are considered. Galilean satellites and small bodies, Venus, geochemistry and regoliths, volcanic and aeolian processes and landforms, fluvial and periglacial processes, and planetary impact cratering, remote sensing, and cartography are discussed

  2. Global environmental governance and planetary boundaries: An introduction

    NARCIS (Netherlands)

    Galaz, V.; Biermann, F.; Folke, C.; Nilsson, M.; Olsson, P.

    2012-01-01

    The notion of 'planetary boundaries' is rapidly diffusing into a range of policy arenas and has clearly stimulated a discussion on the need to reform international environmental governance. This article summarizes the special section "Global Environmental Governance and Planetary Boundaries". The

  3. Planetary boundaries: exploring the safe operating space for humanity

    Science.gov (United States)

    Johan Rockström; Will Steffen; Kevin Noone; Asa Persson; F. Stuart Chapin; Eric Lambin; Timothy M. Lenton; Marten Scheffer; Carl Folke; Hans Joachim Schellnhuber; Björn Nykvist; Cynthia A. de Wit; Terry Hughes; Sander van der Leeuw; Henning Rodhe; Sverker Sörlin; Peter K. Snyder; Robert Costanza; Uno Svedin; Malin Falkenmark; Louise Karlberg; Robert W. Corell; Victoria J. Fabry; James Hansen; Brian Walker; Diana Liverman; Katherine Richardson; Paul Crutzen; Jonathan. Foley

    2009-01-01

    Anthropogenic pressures on the Earth System have reached a scale where abrupt global environmental change can no longer be excluded. We propose a new approach to global sustainability in which we define planetary boundaries within which we expect that humanity can operate safely. Transgressing one or more planetary boundaries may be deleterious or even catastrophic due...

  4. IRAS-22568+6141 - A NEW BIPOLAR PLANETARY-NEBULA

    NARCIS (Netherlands)

    LARIO, PG; MANCHADO, A; RIERA, A; MAMPASO, A; POTTASCH, [No Value

    When carrying out a survey of IRAS sources with infrared colours similar to those of planetary nebulae, IRAS 22568 + 6141 was found to be a new young planetary nebula. It shows an extension of 8" and a bipolar structure. From its optical low resolution spectrum we have derived a high extinction

  5. The solution of complete Schwarzschild's planetary equation with ...

    African Journals Online (AJOL)

    The Einstein's solution of the planetary equation of motion from Schwarzschild's line element is well known. In this paper, we solve the complete Schwarzschild's planetary equation with the method of successive approximation for the corresponding precession and compare the result with that from the line element.

  6. Complete Schwarzschild\\'s planetary equation | Howusu | Journal of ...

    African Journals Online (AJOL)

    In this paper we derive the complete planetary equation from the Schwarzschild's equations of motion and compare it with the corresponding well-known planetary equation from the Schwarzchild's line element. Journal of the Nigerian Association of Mathematical Physics Vol. 8 2004: pp. 265-268 ...

  7. Quasi-Stationary Planetary Wave in the MLT During Summer

    Science.gov (United States)

    Stray, N. H.; Espy, P. J.; Hibbins, R. E.

    2014-12-01

    A network of 8 northern hemispheric SuperDARN radars (51-66N) has been used to study planetary wave activity in the mesosphere lower thermosphere (MLT). The meridional meteor winds from the longitudinally spaced SuperDARN network are used to derive the planetary wave activity with zonal wave numbers 1 and 2 in the polar summer MLT (~95 km). In addition planetary wave amplitudes throughout the middle atmosphere have been retrieved from the meridional wind data of the Modern-Era Retrospective Analysis for Research and Application (MERRA) of the NASA Global Modelling and Assimilation Office. The fitting technique used to derive the planetary wave amplitudes will be presented, and it will be shown that there are strong quasi-stationary longitudinal differences in the strength of the meridional wind in the MLT during summer which can be described as a quasi-stationary planetary wave number 1. The ground-based network allows this planetary wave to be separated from tidal perturbations that are aliased in satellite observations, and the combination of these two data sets provides evidence that the mesopause planetary wave activity is produced in situ in the MLT rather than propagating upwards from lower altitudes. Finally, the impact of this planetary wave feature on Polar Mesospheric Clouds (PMC) and Polar Mesospheric Summer Echoes (PMSE) will be discussed.

  8. Early Planetary Environments and the Origin of Life

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 6; Issue 10. Early Planetary Environments and the Origin of Life - Early Planetary Environments. P V Sukumaran. Series Article Volume 6 Issue 10 October 2001 pp 16-28. Fulltext. Click here to view fulltext PDF. Permanent link:

  9. Revised planetary protection policy for solar system exploration

    Science.gov (United States)

    Devincenzi, D. L.; Stabekis, P. D.

    1984-01-01

    In order to control contamination of planets by terrestrial microorganisms and organic constituents, U.S. planetary missions have been governed by a planetary protection (or planetary quarantine) policy which has changed little since 1972. This policy has recently been reviewed in light of new information obtained from planetary exploration during the past decade and because of changes to, or uncertainties in, some parameters used in the existing quantitative approach. On the basis of this analysis, a revised planetary protection policy with the following key features is proposed: deemphasizing the use of mathematical models and quantitative analyses; establishing requirements for target planet/mission type (i.e., Orbiter, Lander, etc.) combinations; considering sample return missions a separate category; simplifying documentation; and imposing implementing procedures (i.e., trajectory biasing, cleanroom assembly, spacecraft sterilization, etc.) by exception, i.e., only if the planet/mission combination warrants such controls.

  10. Ideas for Testing of Planetary Gear Sets of Automotive Transmissions

    Directory of Open Access Journals (Sweden)

    Achtenová Gabriela

    2017-06-01

    Full Text Available The article describes the concept of modular stand, where is possible to provide tests of gear pairs with fixed axes from mechanical automotive gearboxes, as well as tests of separate planetary sets from automatic gearboxes. Special attention in the article will be paid to the variant dedicated for testing of planetary gear sets. This variant is particularly interesting because: 1 it is rarely described in the literature, and 2 this topology allows big simplification with respect to testing of standard gearwheels. In the planetary closed-loop stand it is possible to directly link two identical planetary sets. Without any bracing flange or other connecting clutches, shafts or gear sets, just two planetary sets face-to-face will be assembled and connected to the electric motor.

  11. Derivation of a planetary ionospheric storm index

    Directory of Open Access Journals (Sweden)

    T. L. Gulyaeva

    2008-09-01

    Full Text Available The planetary ionospheric storm index, Wp, is deduced from the numerical global ionospheric GPS-IONEX maps of the vertical total electron content, TEC, for more than half a solar cycle, 1999–2008. The TEC values are extracted from the 600 grid points of the map at latitudes 60° N to 60° S with a step of 5° and longitudes 0° to 345° E with a step of 15° providing the data for 00:00 to 23:00 h of local time. The local effects of the solar radiant energy are filtered out by normalizing of the TEC in terms of the solar zenith angle χ at a particular time and the local noon value χ0. The degree of perturbation, DTEC, is computed as log of TEC relative to quiet reference median for 27 days prior to the day of observation. The W-index map is generated by segmentation of DTEC with the relevant thresholds specified earlier for foF2 so that 1 or −1 stands for the quiet state, 2 or −2 for the moderate disturbance, 3 or −3 for the moderate ionospheric storm, and 4 or −4 for intense ionospheric storm at each grid point of the map. The planetary ionospheric storm Wp index is obtained from the W-index map as a latitudinal average of the distance between maximum positive and minimum negative W-index weighted by the latitude/longitude extent of the extreme values on the map. The threshold Wp exceeding 4.0 index units and the peak value Wpmax≥6.0 specify the duration and the power of the planetary ionosphere-plasmasphere storm. It is shown that the occurrence of the Wp storms is growing with the phase of the solar cycle being twice as much as the number of the magnetospheric storms with Dst≤−100 nT and Ap≥100 nT.

  12. Derivation of a planetary ionospheric storm index

    Directory of Open Access Journals (Sweden)

    T. L. Gulyaeva

    2008-09-01

    Full Text Available The planetary ionospheric storm index, Wp, is deduced from the numerical global ionospheric GPS-IONEX maps of the vertical total electron content, TEC, for more than half a solar cycle, 1999–2008. The TEC values are extracted from the 600 grid points of the map at latitudes 60° N to 60° S with a step of 5° and longitudes 0° to 345° E with a step of 15° providing the data for 00:00 to 23:00 h of local time. The local effects of the solar radiant energy are filtered out by normalizing of the TEC in terms of the solar zenith angle χ at a particular time and the local noon value χ0. The degree of perturbation, DTEC, is computed as log of TEC relative to quiet reference median for 27 days prior to the day of observation. The W-index map is generated by segmentation of DTEC with the relevant thresholds specified earlier for foF2 so that 1 or −1 stands for the quiet state, 2 or −2 for the moderate disturbance, 3 or −3 for the moderate ionospheric storm, and 4 or −4 for intense ionospheric storm at each grid point of the map. The planetary ionospheric storm Wp index is obtained from the W-index map as a latitudinal average of the distance between maximum positive and minimum negative W-index weighted by the latitude/longitude extent of the extreme values on the map. The threshold Wp exceeding 4.0 index units and the peak value Wpmax≥6.0 specify the duration and the power of the planetary ionosphere-plasmasphere storm. It is shown that the occurrence of the Wp storms is growing with the phase of the solar cycle being twice as much as the number of the magnetospheric storms with Dst≤−100 nT and Ap≥100 nT.

  13. In-situ Planetary Subsurface Imaging System

    Science.gov (United States)

    Song, W.; Weber, R. C.; Dimech, J. L.; Kedar, S.; Neal, C. R.; Siegler, M.

    2017-12-01

    Geophysical and seismic instruments are considered the most effective tools for studying the detailed global structures of planetary interiors. A planet's interior bears the geochemical markers of its evolutionary history, as well as its present state of activity, which has direct implications to habitability. On Earth, subsurface imaging often involves massive data collection from hundreds to thousands of geophysical sensors (seismic, acoustic, etc) followed by transfer by hard links or wirelessly to a central location for post processing and computing, which will not be possible in planetary environments due to imposed mission constraints on mass, power, and bandwidth. Emerging opportunities for geophysical exploration of the solar system from Venus to the icy Ocean Worlds of Jupiter and Saturn dictate that subsurface imaging of the deep interior will require substantial data reduction and processing in-situ. The Real-time In-situ Subsurface Imaging (RISI) technology is a mesh network that senses and processes geophysical signals. Instead of data collection then post processing, the mesh network performs the distributed data processing and computing in-situ, and generates an evolving 3D subsurface image in real-time that can be transmitted under bandwidth and resource constraints. Seismic imaging algorithms (including traveltime tomography, ambient noise imaging, and microseismic imaging) have been successfully developed and validated using both synthetic and real-world terrestrial seismic data sets. The prototype hardware system has been implemented and can be extended as a general field instrumentation platform tailored specifically for a wide variety of planetary uses, including crustal mapping, ice and ocean structure, and geothermal systems. The team is applying the RISI technology to real off-world seismic datasets. For example, the Lunar Seismic Profiling Experiment (LSPE) deployed during the Apollo 17 Moon mission consisted of four geophone instruments

  14. PROC: a new Planetary Radars Operating Centre

    Science.gov (United States)

    Catallo, C.; Alberti, G.; Flamini, E.; Olivieri, A.; Orosei, R.

    2009-12-01

    Planetary exploration by means of radar systems, mainly using Ground Penetrating Radars (GPR) is an important role of Italy and numerous scientific international space programs are carried out jointly with ESA and NASA by Italian Space Agency, the scientific community and the industry. Actually three important experiments under Italian leadership ( designed and manufactured by the Italian industry) provided by ASI within a NASA/ESA/ASI joint venture framework are operating in the frame of an extended missions : MARSIS on-board Mars Express, SHARAD on-board Mars Reconnaissance Orbiter and CASSINI Radar on-board Cassini spacecraft. Three dedicated operational centers, namely SHOC, (Sharad Operating Centre), MOC (Marsis Operating Center) and CASSINI PAD are operating from the starting of the missions in order In order to support all the scientific communities, institutional customers and experiment teams operation Each center is dedicated to a single instrument management and control, data processing and distribution and even if they had been conceived to operate autonomously and independently one from each other, synergies and overlaps have been envisaged leading to the suggestion of a unified center, the Planetary Radar Processing Center (PROC). In order to harmonize operations either from logistics point of view and from HW/SW capabilities point of view PROC is designed and developed for offering improved functionalities to increase capabilities, mainly in terms of data exchange, comparison, interpretation and exploitation. PROC is, therefore, conceived as the Italian support facility to the scientific community for on-going and future Italian planetary exploration programs, such as Europa-Jupiter System Mission (EJSM) The paper describes how PROC is designed and developed, to allow SHOC, MOC and CASSINI PAD to operate as before, and to offer improved functionalities to increase capabilities, mainly in terms of data exchange, comparison, interpretation and

  15. An enhanced Planetary Radar Operating Centre (PROC)

    Science.gov (United States)

    Catallo, C.

    2010-12-01

    Planetary exploration by means of radar systems, mainly using GPRs is an important role of Italy and numerous scientific international space programs are carried out jointly with ESA and NASA by Italian Space Agency, the scientific community and the industry. Three experiments under Italian leadership ( designed and manufactured by the Italian industry) provided by ASI within a NASA/ESA/ASI joint venture framework are successfully operating: MARSIS on-board MEX, SHARAD on-board MRO and CASSINI Radar on-board Cassini spacecraft: the missions have been further extended . Three dedicated operational centers, namely SHOC, (Sharad Operating Centre), MOC (Marsis Operating Center) and CASSINI PAD are operating from the missions beginning to support all the scientific communities, institutional customers and experiment teams operation Each center is dedicated to a single instrument management and control, data processing and distribution and even if they had been conceived to operate autonomously and independently one from each other, synergies and overlaps have been envisaged leading to the suggestion of a unified center, the Planetary Radar Processing Center (PROC). In order to harmonize operations either from logistics point of view and from HW/SW capabilities point of view PROC is designed and developed for offering improved functionalities to increase capabilities, mainly in terms of data exchange, comparison, interpretation and exploitation. PROC is, therefore, conceived as the Italian support facility to the scientific community for on-going and future Italian planetary exploration programs, such as Europa-Jupiter System Mission (EJSM) The paper describes how the new PROC is designed and developed, to allow SHOC, MOC and CASSINI PAD to operate as before, and to offer improved functionalities to increase capabilities, mainly in terms of data exchange, comparison, interpretation and exploitation aiding scientists to increase their knowledge in the field of surface

  16. Planetary Atmospheres and Evolution of Complex Life

    Science.gov (United States)

    Catling, D.

    2014-04-01

    Let us define "complex life" as actively mobile organisms exceeding tens of centimeter size scale with specialized, differentiated anatomy comparable to advanced metazoans. Such organisms on any planet will need considerable energy for growth and metabolism, and an atmosphere is likely to play a key role. The history of life on Earth suggests that there were at least two major hurdles to overcome before complex life developed. The first was biological. Large, three-dimensional multicellular animals and plants are made only of eukaryotic cells, which are the only type that can develop into a large, diverse range of cell types unlike the cells of microbes. Exactly how eukaryotes allow 3D multicellularity and how they originated are matters of debate. But the internal structure and bigger and more modular genomes of eukaryotes are important factors. The second obstacle for complex life was having sufficient free, diatomic oxygen (O2). Aerobic metabolism provides about an order of magnitude more energy for a given intake of food than anaerobic metabolism, so anaerobes don't grow multicellular beyond filaments because of prohibitive growth efficiencies. A precursor to a 2.4 Ga rise of oxygen was the evolution of water-splitting, oxygen-producing photosynthesis. But although the atmosphere became oxidizing at 2.4 Ga, sufficient atmospheric O2 did not occur until about 0.6 Ga. Earth-system factors were involved including planetary outgassing (as affected by size and composition), hydrogen escape, and processing of organic carbon. An atmosphere rich in O2 provides the largest feasible energy source per electron transfer in the Periodic Table, which suggests that O2 would be important for complex life on exoplanets. But plentiful O2 is unusual in a planetary atmosphere because O2 is easily consumed in chemical reactions with reducing gases or surface materials. Even with aerobic metabolism, the partial pressure of O2 (pO2) must exceed 10^3 Pa to allow organisms that rely on

  17. Reconstruction of neutron spectra through neural networks

    International Nuclear Information System (INIS)

    Vega C, H.R.; Hernandez D, V.M.; Manzanares A, E.

    2003-01-01

    A neural network has been used to reconstruct the neutron spectra starting from the counting rates of the detectors of the Bonner sphere spectrophotometric system. A group of 56 neutron spectra was selected to calculate the counting rates that would produce in a Bonner sphere system, with these data and the spectra it was trained the neural network. To prove the performance of the net, 12 spectra were used, 6 were taken of the group used for the training, 3 were obtained of mathematical functions and those other 3 correspond to real spectra. When comparing the original spectra of those reconstructed by the net we find that our net has a poor performance when reconstructing monoenergetic spectra, this attributes it to those characteristic of the spectra used for the training of the neural network, however for the other groups of spectra the results of the net are appropriate with the prospective ones. (Author)

  18. Inclusive spectra in hard processes

    International Nuclear Information System (INIS)

    Kiselev, A.V.; Petrov, V.A.

    1985-01-01

    It is shown that the unified mechanism of hadronization in hard processes results in universality of inclusive spectra of soft hadrons. Inclusive spectrum of hadrons in energy share in deep-inelastic lepton-hadron scattering is calculated. The spectrum obtained is calculated with analogous distribution in e + e - annihilation. It is noted that inclusive spectrum of soft hadrons in hard processes is described by a universal function

  19. ACCELERATED FITTING OF STELLAR SPECTRA

    International Nuclear Information System (INIS)

    Ting, Yuan-Sen; Conroy, Charlie; Rix, Hans-Walter

    2016-01-01

    Stellar spectra are often modeled and fitted by interpolating within a rectilinear grid of synthetic spectra to derive the stars’ labels: stellar parameters and elemental abundances. However, the number of synthetic spectra needed for a rectilinear grid grows exponentially with the label space dimensions, precluding the simultaneous and self-consistent fitting of more than a few elemental abundances. Shortcuts such as fitting subsets of labels separately can introduce unknown systematics and do not produce correct error covariances in the derived labels. In this paper we present a new approach—Convex Hull Adaptive Tessellation (chat)—which includes several new ideas for inexpensively generating a sufficient stellar synthetic library, using linear algebra and the concept of an adaptive, data-driven grid. A convex hull approximates the region where the data lie in the label space. A variety of tests with mock data sets demonstrate that chat can reduce the number of required synthetic model calculations by three orders of magnitude in an eight-dimensional label space. The reduction will be even larger for higher dimensional label spaces. In chat the computational effort increases only linearly with the number of labels that are fit simultaneously. Around each of these grid points in the label space an approximate synthetic spectrum can be generated through linear expansion using a set of “gradient spectra” that represent flux derivatives at every wavelength point with respect to all labels. These techniques provide new opportunities to fit the full stellar spectra from large surveys with 15–30 labels simultaneously.

  20. Hydrogen Dimers in Giant-planet Infrared Spectra

    Science.gov (United States)

    Fletcher, Leigh N.; Gustafsson, Magnus; Orton, Glenn S.

    2018-03-01

    Despite being one of the weakest dimers in nature, low-spectral-resolution Voyager/IRIS observations revealed the presence of (H2)2 dimers on Jupiter and Saturn in the 1980s. However, the collision-induced H2–H2 opacity databases widely used in planetary science have thus far only included free-to-free transitions and have neglected the contributions of dimers. Dimer spectra have both fine-scale structure near the S(0) and S(1) quadrupole lines (354 and 587 cm‑1, respectively), and broad continuum absorption contributions up to ±50 cm‑1 from the line centers. We develop a new ab initio model for the free-to-bound, bound-to-free, and bound-to-bound transitions of the hydrogen dimer for a range of temperatures (40–400 K) and para-hydrogen fractions (0.25–1.0). The model is validated against low-temperature laboratory experiments, and used to simulate the spectra of the giant planets. The new collision-induced opacity database permits high-resolution (0.5–1.0 cm‑1) spectral modeling of dimer spectra near S(0) and S(1) in both Cassini Composite Infrared Spectrometer observations of Jupiter and Saturn, and in Spitzer Infrared Spectrometer (IRS) observations of Uranus and Neptune for the first time. Furthermore, the model reproduces the dimer signatures observed in Voyager/IRIS data near S(0) on Jupiter and Saturn, and generally lowers the amount of para-H2 (and the extent of disequilibrium) required to reproduce IRIS observations.

  1. The NASA Planetary Data System's Cartography and Imaging Sciences Node and the Planetary Spatial Data Infrastructure (PSDI) Initiative

    Science.gov (United States)

    Gaddis, L. R.; Laura, J.; Hare, T.; Hagerty, J.

    2017-06-01

    Here we address the role of the PSDI initiative in the context of work to archive and deliver planetary data by NASA’s Planetary Data System, and in particular by the PDS Cartography and Imaging Sciences Discipline Node (aka “Imaging” or IMG).

  2. NASA Planetary Science Summer School: Preparing the Next Generation of Planetary Mission Leaders

    Science.gov (United States)

    Lowes, L. L.; Budney, C. J.; Sohus, A.; Wheeler, T.; Urban, A.; NASA Planetary Science Summer School Team

    2011-12-01

    Sponsored by NASA's Planetary Science Division, and managed by the Jet Propulsion Laboratory, the Planetary Science Summer School prepares the next generation of engineers and scientists to participate in future solar system exploration missions. Participants learn the mission life cycle, roles of scientists and engineers in a mission environment, mission design interconnectedness and trade-offs, and the importance of teamwork. For this professional development opportunity, applicants are sought who have a strong interest and experience in careers in planetary exploration, and who are science and engineering post-docs, recent PhDs, and doctoral students, and faculty teaching such students. Disciplines include planetary science, geoscience, geophysics, environmental science, aerospace engineering, mechanical engineering, and materials science. Participants are selected through a competitive review process, with selections based on the strength of the application and advisor's recommendation letter. Under the mentorship of a lead engineer (Dr. Charles Budney), students select, design, and develop a mission concept in response to the NASA New Frontiers Announcement of Opportunity. They develop their mission in the JPL Advanced Projects Design Team (Team X) environment, which is a cross-functional multidisciplinary team of professional engineers that utilizes concurrent engineering methodologies to complete rapid design, analysis and evaluation of mission concept designs. About 36 students participate each year, divided into two summer sessions. In advance of an intensive week-long session in the Project Design Center at JPL, students select the mission and science goals during a series of six weekly WebEx/telecons, and develop a preliminary suite of instrumentation and a science traceability matrix. Students assume both a science team and a mission development role with JPL Team X mentors. Once at JPL, students participate in a series of Team X project design sessions

  3. The New Planetary Science Archive (PSA): Exploration and Discovery of Scientific Datasets from ESA's Planetary Missions

    Science.gov (United States)

    Heather, David; Besse, Sebastien; Vallat, Claire; Barbarisi, Isa; Arviset, Christophe; De Marchi, Guido; Barthelemy, Maud; Coia, Daniela; Costa, Marc; Docasal, Ruben; Fraga, Diego; Grotheer, Emmanuel; Lim, Tanya; MacFarlane, Alan; Martinez, Santa; Rios, Carlos; Vallejo, Fran; Saiz, Jaime

    2017-04-01

    The Planetary Science Archive (PSA) is the European Space Agency's (ESA) repository of science data from all planetary science and exploration missions. The PSA provides access to scientific datasets through various interfaces at http://psa.esa.int. All datasets are scientifically peer-reviewed by independent scientists, and are compliant with the Planetary Data System (PDS) standards. The PSA is currently implementing a number of significant improvements, mostly driven by the evolution of the PDS standard, and the growing need for better interfaces and advanced applications to support science exploitation. As of the end of 2016, the PSA is hosting data from all of ESA's planetary missions. This includes ESA's first planetary mission Giotto that encountered comet 1P/Halley in 1986 with a flyby at 800km. Science data from Venus Express, Mars Express, Huygens and the SMART-1 mission are also all available at the PSA. The PSA also contains all science data from Rosetta, which explored comet 67P/Churyumov-Gerasimenko and asteroids Steins and Lutetia. The year 2016 has seen the arrival of the ExoMars 2016 data in the archive. In the upcoming years, at least three new projects are foreseen to be fully archived at the PSA. The BepiColombo mission is scheduled for launch in 2018. Following that, the ExoMars Rover Surface Platform (RSP) in 2020, and then the JUpiter ICy moon Explorer (JUICE). All of these will archive their data in the PSA. In addition, a few ground-based support programmes are also available, especially for the Venus Express and Rosetta missions. The newly designed PSA will enhance the user experience and will significantly reduce the complexity for users to find their data promoting one-click access to the scientific datasets with more customized views when needed. This includes a better integration with Planetary GIS analysis tools and Planetary interoperability services (search and retrieve data, supporting e.g. PDAP, EPN-TAP). It will also be up

  4. Lunar and Planetary Science XXXV: Concerning Chondrites

    Science.gov (United States)

    2004-01-01

    The Lunar and Planetary Science XXXV session entitled "Concerning Chondrites" includes the following topics: 1) Petrology and Raman Spectroscopy of Shocked Phases in the Gujba CB Chondrite and the Shock History of the CB Parent Body; 2) The Relationship Between CK and CV Chondrites: A Single Parent Body Source? 3) Samples of Asteroid Surface Ponded Deposits in Chondritic Meteorites; 4) Composition and Origin of SiO2-rich Objects in Carbonaceous and Ordinary Chondrites; 5) Re-Os Systematics and HSE distribution in Tieschitz (H3.6); Two Isochrons for One Meteorite; 6) Loss of Chromium from Olivine During the Metamorphism of Chondrites; 7) Very Short Delivery Times of Meteorites After the L-Chondrite Parent Body Break-Up 480 Myr Ago; and 8) The Complex Exposure History of a Very Large L/LL5 Chondrite Shower: Queen Alexandra Range 90201.

  5. Sustainable food systems for optimal planetary health.

    Science.gov (United States)

    Canavan, Chelsey R; Noor, Ramadhani A; Golden, Christopher D; Juma, Calestous; Fawzi, Wafaie

    2017-06-01

    Sustainable food systems are an important component of a planetary health strategy to reduce the threat of infectious disease, minimize environmental footprint and promote nutrition. Human population trends and dietary transition have led to growing demand for food and increasing production and consumption of meat, amid declining availability of arable land and water. The intensification of livestock production has serious environmental and infectious disease impacts. Land clearing for agriculture alters ecosystems, increases human-wildlife interactions and leads to disease proliferation. Context-specific interventions should be evaluated towards optimizing nutrition resilience, minimizing environmental footprint and reducing animal and human disease risk. © The Author 2017. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.

  6. Shape, structure, and morphology in planetary nebulae

    Science.gov (United States)

    Shaw, Richard A.

    2012-08-01

    A revival over the past two decades in planetary nebula (PN) morphological studies springs from a combination of factors, including the advent of wide-area, high dynamic range detectors; the growing archives of high resolution images from the X-ray to the sub-mm; and the advent of sophisticated models of the co-evolution of PNe and their central stars. Yet the story of PN formation from their immediate precursors, the AGB stars, is not yet fully written. PN morphology continues to inspire, provide context for physical interpretation, and serve as an ultimate standard of comparison for many investigations in this area of astrophysics. After a brief review of the remarkable successes of PN morphology, I summarize how this tool has been employed over the last half-decade to advance our understanding of PNe.

  7. Planetary magnetospheres: the in situ astrophysical laboratories

    International Nuclear Information System (INIS)

    Krimigis, S.M.

    1982-01-01

    The magnetosphere of Earth is described first because it represents the one most extensively studied to date, and serve as the baseline for characterizing the phenomena to be observed in other planetary magnetospheres. The magnetospheres of the inner planets (Mercury, Venus and Mars) are examined next and then a description of the magnetospheres of the outer planets are presented. The description of the magnetosphere of Jupiter form the bulk of the paper, not only because of its enormous size and rich variety of physical phenomena within, but because it may represent the closest analog to the many astrophysical objects thought to possess magnetospheres. Several properties characteristic of magnetospheres in general will then be pointed out, and the significance of the findings is discussed in the context of solar system and astrophysical plasmas

  8. Planetary Overload, Limits to Growth and Health.

    Science.gov (United States)

    Butler, Colin D

    2016-12-01

    Since the use of atomic weapons in 1945 visionaries have warned that without major changes the survival of global civilization is in question. These concerns deepened in following decades, during the Cold War, with The Limits to Growth, the best-selling environmental book of the 1970s. Yet, since then, most concern has faded, fuelled by technological developments and a shift in dominant global ideology. Public health, with a few exceptions (one of which is the book Planetary Overload), has been slow to recognize this debate, even as evidence emerges that civilization may indeed be at risk, driven by an increasingly ominous complex of events. This article outlines the key relevant literature and concepts, attempting to bring emerging and future health consequences to the attention of health workers, including the idea of a "social vaccine," conveying sufficient anxiety to provoke action for environmental protection, but insufficient to induce paralysis.

  9. Arctic Climate and Atmospheric Planetary Waves

    Science.gov (United States)

    Cavalieri, D. J.; Haekkinen, S.; Zukor, Dorothy J. (Technical Monitor)

    2001-01-01

    Analysis of a fifty-year record (1946-1995) of monthly-averaged sea level pressure data provides a link between the phases of planetary-scale sea level pressure waves and Arctic Ocean and ice variability. Results of this analysis show: (1) a breakdown of the dominant wave 1 pattern in the late 1960's, (2) shifts in the mean phase of waves 1 and 2 since this breakdown, (3) an eastward shift in the phases of both waves 1 and 2 during the years of simulated cyclonic Arctic Ocean circulation relative to their phases during the years of anticyclonic circulation, (4) a strong decadal variability of wave phase associated with simulated Arctic Ocean circulation changes. Finally, the Arctic atmospheric circulation patterns that emerge when waves 1 and 2 are in their extreme eastern and western positions suggest an alternative approach for determining significant forcing patterns of sea ice and high-latitude variability.

  10. Adaptive multisensor fusion for planetary exploration rovers

    Science.gov (United States)

    Collin, Marie-France; Kumar, Krishen; Pampagnin, Luc-Henri

    1992-01-01

    The purpose of the adaptive multisensor fusion system currently being designed at NASA/Johnson Space Center is to provide a robotic rover with assured vision and safe navigation capabilities during robotic missions on planetary surfaces. Our approach consists of using multispectral sensing devices ranging from visible to microwave wavelengths to fulfill the needs of perception for space robotics. Based on the illumination conditions and the sensors capabilities knowledge, the designed perception system should automatically select the best subset of sensors and their sensing modalities that will allow the perception and interpretation of the environment. Then, based on reflectance and emittance theoretical models, the sensor data are fused to extract the physical and geometrical surface properties of the environment surface slope, dielectric constant, temperature and roughness. The theoretical concepts, the design and first results of the multisensor perception system are presented.

  11. Handbook of cosmic hazards and planetary defense

    CERN Document Server

    Allahdadi, Firooz

    2015-01-01

    Covers in a comprehensive fashion all aspects of cosmic hazards and possible strategies for contending with these threats through a comprehensive planetary defense strategy. This handbook brings together in a single reference work a rich blend of information about the various types of cosmic threats that are posed to human civilization by asteroids, comets, bolides, meteors, solar flares and coronal mass ejections, cosmic radiation and other types of threats that are only recently beginning to be understood and studied, such as investigation of the “cracks” in the protective shield provided by the Van Allen belts and the geomagnetosphere, of matter-antimatter collisions, orbital debris and radiological or biological contamination. Some areas that are addressed involve areas about which there is a good deal of information that has been collected for many decades by multiple space missions run by many different space agencies, observatories and scientific researchers. Other areas involving research and ...

  12. Spice Tools Supporting Planetary Remote Sensing

    Science.gov (United States)

    Acton, C.; Bachman, N.; Semenov, B.; Wright, E.

    2016-06-01

    NASA's "SPICE"* ancillary information system has gradually become the de facto international standard for providing scientists the fundamental observation geometry needed to perform photogrammetry, map making and other kinds of planetary science data analysis. SPICE provides position and orientation ephemerides of both the robotic spacecraft and the target body; target body size and shape data; instrument mounting alignment and field-of-view geometry; reference frame specifications; and underlying time system conversions. SPICE comprises not only data, but also a large suite of software, known as the SPICE Toolkit, used to access those data and subsequently compute derived quantities-items such as instrument viewing latitude/longitude, lighting angles, altitude, etc. In existence since the days of the Magellan mission to Venus, the SPICE system has continuously grown to better meet the needs of scientists and engineers. For example, originally the SPICE Toolkit was offered only in Fortran 77, but is now available in C, IDL, MATLAB, and Java Native Interface. SPICE calculations were originally available only using APIs (subroutines), but can now be executed using a client-server interface to a geometry engine. Originally SPICE "products" were only available in numeric form, but now SPICE data visualization is also available. The SPICE components are free of cost, license and export restrictions. Substantial tutorials and programming lessons help new users learn to employ SPICE calculations in their own programs. The SPICE system is implemented and maintained by the Navigation and Ancillary Information Facility (NAIF)-a component of NASA's Planetary Data System (PDS). * Spacecraft, Planet, Instrument, Camera-matrix, Events

  13. Manned flight and planetary scientific exploration.

    Science.gov (United States)

    Muller, Christian; Moreau, Didier

    2014-05-01

    Human explorers had a fundamental role in the success of the APOLLO moon programme, they were at the same time the indispensable pilots, scientific operators and on the last missions lead scientists. Since, man did not either return to the moon or land on Mars but manned operation centres on the earth are now conducting extensive telescience on both celestial bodies. Manned flights to moon, Mars and asteroids are however still on the agenda and even if the main drive of these projects is outside science, it is to the planetary scientists to both prepare the data bases necessary for these flights and to ensure that the scientific advantage of conducting research in real time and in situ is exploited to the maximum. The current manned flight programme in Europe concentrates on the use of the International Space Station, the scientific activities can be roughly divided between the pressurized payloads and the external payloads. Technology developments occur also in parallel and prepare new exploration techniques. The current planning leads to exploitation up to 2020 but the space agencies study further extensions, the date of 2028 having already been considered. The relation of these programmes to future manned planetary exploration will be described both from the science and development point of view. The complementary role of astronauts and ground operation centres will be described on the basis of the current experience of operation centres managing the International Space Station. Finally, the NASA ORION project of exploration in the solar system will be described with emphasis on its current European participations. The science opportunities presented by independent ventures as Inspiration Mars or Mars One will be presented.

  14. An Ion-Propelled Cubesat for Planetary Defense and Planetary Science

    Science.gov (United States)

    Russell, Christopher T.; Wirz, Richard; Lai, Hairong; Li, Jian-Yang; Connors, Martin

    2017-04-01

    Small satellites can reduce the cost of launch by riding along with other payloads on a large rocket or being launched on a small rocket, but are perceived as having limited capabilities. This perception can be at least partially overcome by innovative design, including ample in-flight propulsion. This allows achieving multiple targets and adaptive exploration. Ion propulsion has been pioneered on Deep Space 1 and honed on the long-duration, multiple-planetary body mission Dawn. Most importantly, the operation of such a mission is now well- understood, including navigation, communication, and science operations for remote sensing. We examined different mission concepts that can be used for both planetary defense and planetary science near 1 AU. Such a spacecraft would travel in the region between Venus and Mars, allowing a complete inventory of material above, including objects down to about 10m diameter to be inventoried. The ion engines could be used to approach these bodies slowly and carefully and allow the spacecraft to map debris and follow its collisional evolution throughout its orbit around the Sun, if so desired. The heritage of Dawn operations experience enables the mission to be operated inexpensively, and the engineering heritage will allow it to be operated for many trips around the Sun.

  15. Remote compositional analysis of lunar olivine-rich lithologies with Moon Mineralogy Mapper (M3) spectra

    Science.gov (United States)

    Isaacson, P.J.; Pieters, C.M.; Besse, S.; Clark, R.N.; Head, J.W.; Klima, R.L.; Mustard, J.F.; Petro, N.E.; Staid, M.I.; Sunshine, J.M.; Taylor, L.A.; Thaisen, K.G.; Tompkins, S.

    2011-01-01

    A systematic approach for deconvolving remotely sensed lunar olivine-rich visible to near-infrared (VNIR) reflectance spectra with the Modified Gaussian Model (MGM) is evaluated with Chandrayaan-1 Moon Mineralogy Mapper (M 3) spectra. Whereas earlier studies of laboratory reflectance spectra focused only on complications due to chromite inclusions in lunar olivines, we develop a systematic approach for addressing (through continuum removal) the prominent continuum slopes common to remotely sensed reflectance spectra of planetary surfaces. We have validated our continuum removal on a suite of laboratory reflectance spectra. Suites of olivine-dominated reflectance spectra from a small crater near Mare Moscoviense, the Copernicus central peak, Aristarchus, and the crater Marius in the Marius Hills were analyzed. Spectral diversity was detected in visual evaluation of the spectra and was quantified using the MGM. The MGM-derived band positions are used to estimate the olivine's composition in a relative sense. Spectra of olivines from Moscoviense exhibit diversity in their absorption features, and this diversity suggests some variation in olivine Fe/Mg content. Olivines from Copernicus are observed to be spectrally homogeneous and thus are predicted to be more compositionally homogeneous than those at Moscoviense but are of broadly similar composition to the Moscoviense olivines. Olivines from Aristarchus and Marius exhibit clear spectral differences from those at Moscoviense and Copernicus but also exhibit features that suggest contributions from other phases. If the various precautions discussed here are weighed carefully, the methods presented here can be used to make general predictions of absolute olivine composition (Fe/Mg content). Copyright ?? 2011 by the American Geophysical Union.

  16. Cool DZ white dwarfs II: Compositions and evolution of old remnant planetary systems

    Science.gov (United States)

    Hollands, M. A.; Gänsicke, B. T.; Koester, D.

    2018-03-01

    In a previous study, we analysed the spectra of 230 cool ({T_{eff}} metal contamination, measuring abundances for Ca, Mg, Fe and in some cases Na, Cr, Ti, or Ni. Here we interpret these abundances in terms of the accretion of debris from extrasolar planetesimals, and infer parent body compositions ranging from crust-like (rich in Ca and Ti) to core-like (rich in Fe and Ni). In particular, two white dwarfs, SDSS J0823+0546 and SDSS J0741+3146, which show log[Fe/Ca] > 1.9 dex, and Fe to Ni ratios similar to the bulk Earth, have accreted by far the most core-like exoplanetesimals discovered to date. With cooling ages in the range 1-8 Gyr, these white dwarfs are among the oldest stellar remnants in the Milky Way, making it possible to probe the long-term evolution of their ancient planetary systems. From the decrease in maximum abundances as a function of cooling age, we find evidence that the arrival rate of material on to the white dwarfs decreases by 3 orders of magnitude over a ≃ 6.5 Gyr span in white dwarf cooling ages, indicating that the mass-reservoirs of post-main sequence planetary systems are depleted on a ≃ 1 Gyr e-folding time-scale. Finally, we find that two white dwarfs in our sample are members of wide binaries, and both exhibit atypically high abundances, thus providing strong evidence that distant binary companions can dynamically perturb white dwarf planetary systems.

  17. Comparative investigation of the energetic ion spectra comprising the magnetospheric ring currents of the solar system.

    Science.gov (United States)

    Mauk, B H

    2014-12-01

    Investigated here are factors that control the intensities and shapes of energetic ion spectra that make up the ring current populations of the strongly magnetized planets of the solar system, specifically those of Earth, Jupiter, Saturn, Uranus, and Neptune. Following a previous and similar comparative investigation of radiation belt electrons, we here turn our attention to ions. Specifically, we examine the possible role of the differential ion Kennel-Petschek limit, as moderated by Electromagnetic Ion Cyclotron (EMIC) waves, as a standard for comparing the most intense ion spectra within the strongly magnetized planetary magnetospheres. In carrying out this investigation, the substantial complexities engendered by the very different ion composition distributions of these diverse magnetospheres must be addressed, given that the dispersion properties of the EMIC waves are strongly determined by the ion composition of the plasmas within which the waves propagate. Chosen for comparison are the ion spectra within these systems that are the most intense observed, specifically at 100 keV and 1 MeV. We find that Earth and Jupiter are unique in having their most intense ion spectra likely limited and sculpted by the Kennel-Petschek process. The ion spectra of Saturn, Uranus, and Neptune reside far below their respective limits and are likely limited by interactions with gas and dust (Saturn) and by the absence of robust ion acceleration processes (Uranus and Neptune). Suggestions are provided for further testing the efficacy of the differential Kennel-Petschek limit for ions using the Van Allen Probes.

  18. Design spectra development considering short time histories

    International Nuclear Information System (INIS)

    Weiner, E.O.

    1983-01-01

    The need for generation of seismic acceleration histories to prescribed response spectra arises several ways in structural dynamics. For example, one way of obtaining floor spectra is to generate a history from a foundation spectra and then solve for the floor motion from which a floor spectrum can be obtained. Two separate programs, MODQKE and MDOF, were written to provide a capability of obtaining equipment spectra from design spectra. MODQKE generates or modifies acceleration histories to conform with design spectra pertaining to, say, a foundation. MDOF is a simple linear modal superposition program that solves for equipment support histories using the design spectra conforming histories as input. Equipment spectra, then, are obtained from the support histories using MODQKE

  19. Time-resolved Neutron-gamma-ray Data Acquisition for in Situ Subsurface Planetary Geochemistry

    Science.gov (United States)

    Bodnarik, Julie G.; Burger, Dan Michael; Burger, A.; Evans, L. G.; Parsons, A. M.; Schweitzer, J. S.; Starr R. D.; Stassun, K. G.

    2013-01-01

    The current gamma-ray/neutron instrumentation development effort at NASA Goddard Space Flight Center aims to extend the use of active pulsed neutron interrogation techniques to probe the subsurface elemental composition of planetary bodies in situ. Previous NASA planetary science missions, that used neutron and/or gamma-ray spectroscopy instruments, have relied on neutrons produced from galactic cosmic rays. One of the distinguishing features of this effort is the inclusion of a high intensity 14.1 MeV pulsed neutron generator synchronized with a custom data acquisition system to time each event relative to the pulse. With usually only one opportunity to collect data, it is difficult to set a priori time-gating windows to obtain the best possible results. Acquiring time-tagged, event-by-event data from nuclear induced reactions provides raw data sets containing channel/energy, and event time for each gamma ray or neutron detected. The resulting data set can be plotted as a function of time or energy using optimized analysis windows after the data are acquired. Time windows can now be chosen to produce energy spectra that yield the most statistically significant and accurate elemental composition results that can be derived from the complete data set. The advantages of post-processing gamma-ray time-tagged event-by-event data in experimental tests using our prototype instrument will be demonstrated.

  20. Time-Resolved Data Acquisition for In Situ Subsurface Planetary Geochemistry

    Science.gov (United States)

    Bodnarik, Julia Gates; Burger, Dan M.; Burger, Arnold; Evans, Larry G.; Parsons, Ann M.; Starr, Richard D.; Stassun, Keivan G.

    2012-01-01

    The current gamma-ray/neutron instrumentation development effort at NASA Goddard Space Flight Center aims to extend the use of active pulsed neutron interrogation techniques to probe the subsurface geochemistry of planetary bodies in situ. All previous NASA planetary science missions, that used neutron and/or gamma-ray spectroscopy instruments, have relied on a constant neutron source produced from galactic cosmic rays. One of the distinguishing features of this effort is the inclusion of a high intensity 14.1 MeV pulsed neutron generator synchronized with a custom data acquisition system to time each event relative to the pulse. With usually only one opportunity to collect data, it is difficult to set a priori time-gating windows to obtain the best possible results. Acquiring time-tagged, event-by-event data from nuclear induced reactions provides raw data sets containing channel/energy, and event time for each gamma ray or neutron detected. The resulting data set can be plotted as a function of time or energy using optimized analysis windows after the data are acquired. Time windows can now be chosen to produce energy spectra that yield the most statistically significant and accurate elemental composition results that can be derived from the complete data set. The advantages of post-processing gamma-ray time-tagged event-by-event data in experimental tests using our prototype instrument will be demonstrated.

  1. ESA's Planetary Science Archive: Preserve and present reliable scientific data sets

    Science.gov (United States)

    Besse, S.; Vallat, C.; Barthelemy, M.; Coia, D.; Costa, M.; De Marchi, G.; Fraga, D.; Grotheer, E.; Heather, D.; Lim, T.; Martinez, S.; Arviset, C.; Barbarisi, I.; Docasal, R.; Macfarlane, A.; Rios, C.; Saiz, J.; Vallejo, F.

    2018-01-01

    The European Space Agency (ESA) Planetary Science Archive (PSA) is undergoing a significant refactoring of all its components to improve the services provided to the scientific community and the public. The PSA supports ESA's missions exploring the Solar System by archiving scientific peer-reviewed observations as well as engineering data sets. This includes the Giotto, SMART-1, Huygens, Venus Express, Mars Express, Rosetta, Exomars 2016, Exomars RSP, BepiColombo, and JUICE missions. The PSA is offering a newly designed graphical user interface which is simultaneously meant to maximize the interaction with scientific observations and also minimise the efforts needed to download these scientific observations. The PSA still offers the same services as before (i.e., FTP, documentation, helpdesk, etc.). In addition, it will support the two formats of the Planetary Data System (i.e., PDS3 and PDS4), as well as providing new ways for searching the data products with specific metadata and geometrical parameters. As well as enhanced services, the PSA will also provide new services to improve the visualisation of data products and scientific content (e.g., spectra, etc.). Together with improved access to the spacecraft engineering data sets, the PSA will provide easier access to scientific data products that will help to maximize the science return of ESA's space missions.

  2. On the new modes of planetary-scale electromagnetic waves in the ionosphere

    Directory of Open Access Journals (Sweden)

    G. D. Aburjania

    2004-04-01

    Full Text Available Using an analogy method the frequencies of new modes of the electromagnetic planetary-scale waves (with a wavelength of 103 km or more, having a weather forming nature, are found at different ionospheric altitudes. This method gives the possibility to determine spectra of ionospheric electromagnetic perturbations directly from the dynamic equations without solving the general dispersion equation. It is shown that the permanently acting factor-latitude variation of the geomagnetic field generates fast and slow weakly damping planetary electromagnetic waves in both the E- and F-layers of the ionosphere. The waves propagate eastward and westward along the parallels. The fast waves have phase velocities (1–5km s–1 and frequencies (10–1–10–4, and the slow waves propagate with velocities of the local winds with frequencies (10–4–10–6s–1 and are generated in the E-region of the ionosphere. Fast waves having phase velocities (10-1500km s–1 and frequencies (1–10–3s–1 are generated in the F-region of the ionosphere. The waves generate the geomagnetic pulsations of the order of one hundred nanoTesla by magnitude. The properties and parameters of the theoretically studied electromagnetic waves agree with those of large-scale ultra-low frequency perturbations observed experimentally in the ionosphere. Key words. Ionosphere (ionospheric disturbances; waves propagation; ionosphere atmosphere interactions

  3. The Planetary Host Red Giant HD47536 - Chemical Composition and Signs of Accretion

    Science.gov (United States)

    Yushchenko, A. V.; Rittipruk, P.; Yushchenko, V. A.; Kang, Y.-W.

    The spectra of HD47536 with resolving power R=30,000 and signal to noise ratio near 100 was obtained at 1.5 meter SMART telescope of CTIO, Chile. The analysis of chemical composition allowed to find the abundances of 33 chemical elements including thorium. The star belongs to halo or intermediate population, it's metallicity is [Fe/H]=-0.58±0.11, the r- and s-processes elements are overabundant with respect to iron. The overabundance of thorium with respect to iron is +0.72 dex. The abundance patternexhibits the clear signs of accretion. The star is a host of two planets, that is why it can be the result of the accretion in planetary system or the accretion of interstellar gas. The signs of accretion are clearly detected and prevent the determination of stellar age.

  4. The signatures of the parental cluster on field planetary systems

    Science.gov (United States)

    Cai, Maxwell Xu; Portegies Zwart, Simon; van Elteren, Arjen

    2018-03-01

    Due to the high stellar densities in young clusters, planetary systems formed in these environments are likely to have experienced perturbations from encounters with other stars. We carry out direct N-body simulations of multiplanet systems in star clusters to study the combined effects of stellar encounters and internal planetary dynamics. These planetary systems eventually become part of the Galactic field population as the parental cluster dissolves, which is where most presently known exoplanets are observed. We show that perturbations induced by stellar encounters lead to distinct signatures in the field planetary systems, most prominently, the excited orbital inclinations and eccentricities. Planetary systems that form within the cluster's half-mass radius are more prone to such perturbations. The orbital elements are most strongly excited in the outermost orbit, but the effect propagates to the entire planetary system through secular evolution. Planet ejections may occur long after a stellar encounter. The surviving planets in these reduced systems tend to have, on average, higher inclinations and larger eccentricities compared to systems that were perturbed less strongly. As soon as the parental star cluster dissolves, external perturbations stop affecting the escaped planetary systems, and further evolution proceeds on a relaxation time-scale. The outer regions of these ejected planetary systems tend to relax so slowly that their state carries the memory of their last strong encounter in the star cluster. Regardless of the stellar density, we observe a robust anticorrelation between multiplicity and mean inclination/eccentricity. We speculate that the `Kepler dichotomy' observed in field planetary systems is a natural consequence of their early evolution in the parental cluster.

  5. Public communication strategy for NASA's planetary protection program

    Science.gov (United States)

    Billings, L.

    The U.S. National Aeronautics and Space Administration (NASA) Planetary Protection Office, in the Office of Space Science, has a long-term initiative under way in communication research and planning. The possibility of extraterrestrial life and efforts to search for evidence of it is one of NASA's key missions, and of great interest to the public. Planetary protection plays a key role in the search for signs of life elsewhere, and as NASA expands its solar system exploration efforts, communication planning for planetary protection must expand to meet growing needs. NASA's Clearly Protection Office has long recognized the importance of communications in accomplishing its goals and objectives. With solar system exploration missions advancing into the era of sample return and with the science of astrobiology changing assumptions about the nature and boundaries of life, the Planetary Protection office is expanding its communication planning efforts and taking first steps toward implementation of a long-term strategy. For the past 10 years, communication research sponsored by the NASA planetary protection program has focused on reaching members of the science community and addressing legal and ethical concerns. In 2003, the program expanded its communication research efforts, initiating the development of a communication strategy based on a participatory model and intended to address the needs of a broad range of extra audiences. The Planetary Protection Office aims to ensure that its scientific, bureaucratic, and other constituencies are fully informed about planetary protection policies and procedures and prepared to communicate with a variety of public audiences about issues relating to planetary protection. This paper will describe NASA's ongoing planetary protection communication research efforts, focusing on development of a participatory communication strategy to enable broadest possible public participation in planning and development of solar system sample

  6. Operator functions and localization of spectra

    CERN Document Server

    Gil’, Michael I

    2003-01-01

    "Operator Functions and Localization of Spectra" is the first book that presents a systematic exposition of bounds for the spectra of various linear nonself-adjoint operators in a Hilbert space, having discrete and continuous spectra. In particular bounds for the spectra of integral, differential and integro-differential operators, as well as finite and infinite matrices are established. The volume also presents a systematic exposition of estimates for norms of operator-valued functions and their applications.

  7. Wavelet spectra of JACEE events

    International Nuclear Information System (INIS)

    Suzuki, Naomichi; Biyajima, Minoru; Ohsawa, Akinori.

    1995-01-01

    Pseudo-rapidity distributions of two high multiplicity events Ca-C and Si-AgBr observed by the JACEE are analyzed by a wavelet transform. Wavelet spectra of those events are calculated and compared with the simulation calculations. The wavelet spectrum of the Ca-C event somewhat resembles that simulated with the uniform random numbers. That of Si-AgBr event, however, is not reproduced by simulation calculations with Poisson random numbers, uniform random numbers, or a p-model. (author)

  8. Rotational spectra and molecular structure

    CERN Document Server

    Wollrab, James E

    1967-01-01

    Physical Chemistry, A Series of Monographs: Rotational Spectra and Molecular Structure covers the energy levels and rotational transitions. This book is divided into nine chapters that evaluate the rigid asymmetric top molecules and the nuclear spin statistics for asymmetric tops. Some of the topics covered in the book are the asymmetric rotor functions; rotational transition intensities; classes of molecules; nuclear spin statistics for linear molecules and symmetric tops; and classical appearance of centrifugal and coriolis forces. Other chapters deal with the energy levels and effects of ce

  9. A radio search for planetary nebulae near the galactic center

    International Nuclear Information System (INIS)

    Isaacman, R.B.

    1980-01-01

    Because of galactic center is a hostile environment, and because planetaries are weak radio emitters, it is not clear a priori that one expects to detect any planetary nebulae at all in the nuclear region of the Galaxy. Therefore the expected lifetime and flux density distribution of galactic center nebulae is considered. The principal observational results from the Westerbork data, and the results of some pilot observations with the Very Large Array, which were intended to distinguish planetaries from other radio sources on an individual basis are given. (Auth.)

  10. Near infrared imager for spectral and polarization analysis of planetary surfaces

    Science.gov (United States)

    Belyaev, D. A.; Yushkov, K. B.; Anikin, S. P.; Evdokimova, N. A.; Potanin, S. A.; Dobrolenskiy, Y. S.; Korablev, O. I.; Molchanov, V. Ya; Mantsevich, S. N.

    2017-09-01

    We propose a concept of an imaging near-IR spectrometer for sensing of planetary surfaces. This instrument is intended to analyze mineralogical and, in some cases, petrographic composition of the upper surface layer in the planetary regolith; to identify and monitor OH/H2O bearing minerals and water adsorption in this layer. The scheme of the spectrometer was designed on a basis of an acousto-optic tunable filter (AOTF) that allows imaging of samples in two orthogonal polarization planes simultaneously. Images are registered as a light (e.g. solar one) reflected and scattered from an observed target in the near infrared spectral range. The AOTF's electrical tuning provides fast and flexible spectral scanning of an image through whole the range analyzed - potentially, ten microseconds per a spectral point. Thus, it is possible to explore reflectance spectra of specified areas on a sample and to detect its minerals composition and microstructure variations. In parallel, one can estimate polarization contrast at different wavelengths thanks to the AOTF's birefringence properties. In this paper we report design and performance of a laboratory prototype for the near-IR spectro-polarimeteric imaging AOTF system operating in the spectral range from 0.8 to 1.75 μm. Reflectance spectra of some minerals were measured with the spectral resolution of 100 cm-1 (passband 10 nm at 1 μm). When imaging samples the spatial resolution as high as 0.5 mm was reached at the target distance of one meter. It corresponds to 100 by 100 resolving elements on the CCD matrix for each of two polarizations of the reflected light. Such a concept is also being designed for the spectral range from 1.7 to 3.5 μm.

  11. Equatorial Oscillation and Planetary Wave Activity in Saturn's Stratosphere Through the Cassini Epoch

    Science.gov (United States)

    Guerlet, S.; Fouchet, T.; Spiga, A.; Flasar, F. M.; Fletcher, L. N.; Hesman, B. E.; Gorius, N.

    2018-01-01

    Thermal infrared spectra acquired by Cassini/Composite InfraRed Spectrometer (CIRS) in limb-viewing geometry in 2015 are used to derive 2-D latitude-pressure temperature and thermal wind maps. These maps are used to study the vertical structure and evolution of Saturn's equatorial oscillation (SEO), a dynamical phenomenon presenting similarities with the Earth's quasi-biennal oscillation (QBO) and semi-annual oscillation (SAO). We report that a new local wind maximum has appeared in 2015 in the upper stratosphere and derive the descent rates of other wind extrema through time. The phase of the oscillation observed in 2015, as compared to 2005 and 2010, remains consistent with a ˜15 year period. The SEO does not propagate downward at a regular rate but exhibits faster descent rate in the upper stratosphere, combined with a greater vertical wind shear, compared to the lower stratosphere. Within the framework of a QBO-type oscillation, we estimate the absorbed wave momentum flux in the stratosphere to be on the order of ˜7 × 10-6 N m-2. On Earth, interactions between vertically propagating waves (both planetary and mesoscale) and the mean zonal flow drive the QBO and SAO. To broaden our knowledge on waves potentially driving Saturn's equatorial oscillation, we searched for thermal signatures of planetary waves in the tropical stratosphere using CIRS nadir spectra. Temperature anomalies of amplitude 1-4 K and zonal wave numbers 1 to 9 are frequently observed, and an equatorial Rossby (n = 1) wave of zonal wave number 3 is tentatively identified in November 2009.

  12. Full Field X-Ray Fluorescence Imaging Using Micro Pore Optics for Planetary Surface Exploration

    Science.gov (United States)

    Sarrazin, P.; Blake, D. F.; Gailhanou, M.; Walter, P.; Schyns, E.; Marchis, F.; Thompson, K.; Bristow, T.

    2016-01-01

    Many planetary surface processes leave evidence as small features in the sub-millimetre scale. Current planetary X-ray fluorescence spectrometers lack the spatial resolution to analyse such small features as they only provide global analyses of areas greater than 100 mm(exp 2). A micro-XRF spectrometer will be deployed on the NASA Mars 2020 rover to analyse spots as small as 120m. When using its line-scanning capacity combined to perpendicular scanning by the rover arm, elemental maps can be generated. We present a new instrument that provides full-field XRF imaging, alleviating the need for precise positioning and scanning mechanisms. The Mapping X-ray Fluorescence Spectrometer - "Map-X" - will allow elemental imaging with approximately 100µm spatial resolution and simultaneously provide elemental chemistry at the scale where many relict physical, chemical and biological features can be imaged in ancient rocks. The arm-mounted Map-X instrument is placed directly on the surface of an object and held in a fixed position during measurements. A 25x25 mm(exp 2) surface area is uniformly illuminated with X-rays or alpha-particles and gamma-rays. A novel Micro Pore Optic focusses a fraction of the emitted X-ray fluorescence onto a CCD operated at a few frames per second. On board processing allows measuring the energy and coordinates of each X-ray photon collected. Large sets of frames are reduced into 2d histograms used to compute higher level data products such as elemental maps and XRF spectra from selected regions of interest. XRF spectra are processed on the ground to further determine quantitative elemental compositions. The instrument development will be presented with an emphasis on the characterization and modelling of the X-ray focussing Micro Pore Optic. An outlook on possible alternative XRF imaging applications will be discussed.

  13. Discovery of a [WO] central star in the planetary nebula Th 2-A

    Science.gov (United States)

    Weidmann, W. A.; Gamen, R.; Díaz, R. J.; Niemela, V. S.

    2008-09-01

    Context: About 2500 planetary nebulae are known in our Galaxy but only 224 have central stars with reported spectral types in the Strasbourg-ESO Catalogue of Galactic Planetary Nebulae (Acker et al. 1992; Acker et al. 1996). Aims: We have started an observational program aiming to increase the number of PN central stars with spectral classification. Methods: By means of spectroscopy and high resolution imaging, we identify the position and true nature of the central star. We carried out low resolution spectroscopic observations at CASLEO telescope, complemented with medium resolution spectroscopy performed at Gemini South and Magellan telescopes. Results: As a first outcome of this survey, we present for the first time the spectra of the central star of the PN Th 2-A. These spectra show emission lines of ionized C and O, typical in Wolf-Rayet stars. Conclusions: We identify the position of that central star, which is not the brightest one of the visual central pair. We classify it as of type [WO 3]pec, which is consistent with the high excitation and dynamical age of the nebula. Based on data collected at (i) the Complejo Astronómico El Leoncito (CASLEO), which is operated under agreement between the Consejo Nacional de Investigaciones Científicas y Técnicas de la República Argentina y Universidades Nacionales de La Plata, Córdoba y San Juan, Argentina; (ii) the 6.5 m Magellan Telescopes at Las Campanas Observatory, Chile; (iii) the 8 m Gemini South Telescope, Chile.

  14. Emirates Mars Mission Planetary Protection Plan

    Science.gov (United States)

    Awadhi, Mohsen Al

    2016-07-01

    The United Arab Emirates is planning to launch a spacecraft to Mars in 2020 as part of the Emirates Mars Mission (EMM). The EMM spacecraft, Amal, will arrive in early 2021 and enter orbit about Mars. Through a sequence of subsequent maneuvers, the spacecraft will enter a large science orbit and remain there throughout the primary mission. This paper describes the planetary protection plan for the EMM mission. The EMM science orbit, where Amal will conduct the majority of its operations, is very large compared to other Mars orbiters. The nominal orbit has a periapse altitude of 20,000 km, an apoapse altitude of 43,000 km, and an inclination of 25 degrees. From this vantage point, Amal will conduct a series of atmospheric investigations. Since Amal's orbit is very large, the planetary protection plan is to demonstrate a very low probability that the spacecraft will ever encounter Mars' surface or lower atmosphere during the mission. The EMM team has prepared methods to demonstrate that (1) the launch vehicle targets support a 0.01% probability of impacting Mars, or less, within 50 years; (2) the spacecraft has a 1% probability or less of impacting Mars during 20 years; and (3) the spacecraft has a 5% probability or less of impacting Mars during 50 years. The EMM mission design resembles the mission design of many previous missions, differing only in the specific parameters and final destination. The following sequence describes the mission: 1.The mission will launch in July, 2020. The launch includes a brief parking orbit and a direct injection to the interplanetary cruise. The launch targets are specified by the hyperbolic departure's energy C3, and the hyperbolic departure's direction in space, captured by the right ascension and declination of the launch asymptote, RLA and DLA, respectively. The targets of the launch vehicle are biased away from Mars such that there is a 0.01% probability or less that the launch vehicle arrives onto a trajectory that impacts Mars

  15. Planetary polarisation measurements with small telescopes

    Science.gov (United States)

    Masding, Philip; Rossi, Loic; Miles, Phil

    2017-04-01

    We have developed a method for measuring the linear polarisation of planets which is accessible to experienced amateur astronomers. The method requires a telescope with an aperture of about 20cm or more together with a linear polarising filter and a planetary imaging camera. Many suitable cameras are available and they can record uncompressed video at frame rates of 10 to 60 per second. Typically this rate will depend on the brightness of the source and size of the telescope. An ideal camera will be monochrome and is used with separate colour filters and a polarising filter. The method is to attach the colour and polarising filters to the camera and record a series of video clips. After recording each video clip the camera and filters are rotated by about 20 degrees until the total rotation is over 180 degrees. Each video clip is then stacked to produce a single low noise image. Most stacking software can sort the video frames according to quality, so the stack is based on a selected percentage of the best frames. There are several freeware stacking programs available which are primarily used for planetary imaging in general but are very suitable for polarisation. Original videos are mostly 8 bit but noise allows the combined stack to have a higher effective resolution and it is saved in 16 bit format. The stacked images are currently processed in Matlab, although the algorithms are being incorporated in Winjupos which is freeware. Results so far have been primarily for Jupiter, but we also have some data for Venus. The Matlab code is used to register the stacked frames (removing any camera rotation) and in the case of Jupiter, compensate for rotation of the planet during the video capture process. Accurate image registration is crucial for this method. A disk function is also applied to allow for the changing illumination angle as the planet rotates. A least squares function calculates the best fit cos squared curve for the variation of light at each point in the

  16. Carbon Dioxide: The Other Planetary Fluid

    Science.gov (United States)

    Glaser, S.; Gamez, D.; Shock, E.

    2016-12-01

    Cometary and interstellar ices have carbon dioxide to water mole ratios of up to 0.3. When melted, such high levels of carbon dioxide cannot all be dissolved in the aqueous phase and instead partition into a CO2-rich (carbonic) fluid. This implies that during the accretion and formation of planetary systems carbonic fluids are not only possible, but common. In fact, they make up the atmosphere of Venus, are found bubbling out of Champagne Vent in the Pacific Ocean, and are documented by metamorphic fluid inclusions. Examination of phase diagrams reveals the conditions where carbonic fluids will exist or predominate. Carbonic fluids are predicted to exist in Earth's subduction zones and under the ice of small ocean worlds. CO2 had previously been shown to completely dissolve into NH­­3­-H­­2O oceans on small icy bodies by forming ammonium carbonate, but the newer measurements of CO2­ abundances indicate that not all of the CO2 can partition into the aqueous fluid as ammonium carbonate. The remaining CO2 would necessarily form a separate carbonic fluid making it likely that liquid CO2 would be a major oceanic component on some small icy bodies. The enhanced solubility of nonpolar and slightly polar organic compounds in carbonic fluids relative to aqueous fluids means that generation, transport, and deposition processes can be greatly enhanced in those cases where carbonic fluids occur. As an example, the solubility of benzoic acid, a polar compound, is about an order of magnitude greater in carbonic than in aqueous fluids, which is surprising given that water is a polar solvent and carbon dioxide is a nonpolar solvent. Anthracene, a nonpolar compound, has an even greater solubility difference between carbonic and aqueous fluids at approximately four orders of magnitude. Highly polar compounds, including most of the building blocks of life, are more soluble in aqueous fluids than in carbonic fluids. The solubility difference of organic molecules in carbonic

  17. Exploring the planetary boundary for chemical pollution.

    Science.gov (United States)

    Diamond, Miriam L; de Wit, Cynthia A; Molander, Sverker; Scheringer, Martin; Backhaus, Thomas; Lohmann, Rainer; Arvidsson, Rickard; Bergman, Åke; Hauschild, Michael; Holoubek, Ivan; Persson, Linn; Suzuki, Noriyuki; Vighi, Marco; Zetzsch, Cornelius

    2015-05-01

    Rockström et al. (2009a, 2009b) have warned that humanity must reduce anthropogenic impacts defined by nine planetary boundaries if "unacceptable global change" is to be avoided. Chemical pollution was identified as one of those boundaries for which continued impacts could erode the resilience of ecosystems and humanity. The central concept of the planetary boundary (or boundaries) for chemical pollution (PBCP or PBCPs) is that the Earth has a finite assimilative capacity for chemical pollution, which includes persistent, as well as readily degradable chemicals released at local to regional scales, which in aggregate threaten ecosystem and human viability. The PBCP allows humanity to explicitly address the increasingly global aspects of chemical pollution throughout a chemical's life cycle and the need for a global response of internationally coordinated control measures. We submit that sufficient evidence shows stresses on ecosystem and human health at local to global scales, suggesting that conditions are transgressing the safe operating space delimited by a PBCP. As such, current local to global pollution control measures are insufficient. However, while the PBCP is an important conceptual step forward, at this point single or multiple PBCPs are challenging to operationalize due to the extremely large number of commercial chemicals or mixtures of chemicals that cause myriad adverse effects to innumerable species and ecosystems, and the complex linkages between emissions, environmental concentrations, exposures and adverse effects. As well, the normative nature of a PBCP presents challenges of negotiating pollution limits amongst societal groups with differing viewpoints. Thus, a combination of approaches is recommended as follows: develop indicators of chemical pollution, for both control and response variables, that will aid in quantifying a PBCP(s) and gauging progress towards reducing chemical pollution; develop new technologies and technical and social

  18. Human-Robot Planetary Exploration Teams

    Science.gov (United States)

    Tyree, Kimberly

    2004-01-01

    The EVA Robotic Assistant (ERA) project at NASA Johnson Space Center studies human-robot interaction and robotic assistance for future human planetary exploration. Over the past four years, the ERA project has been performing field tests with one or more four-wheeled robotic platforms and one or more space-suited humans. These tests have provided experience in how robots can assist humans, how robots and humans can communicate in remote environments, and what combination of humans and robots works best for different scenarios. The most efficient way to understand what tasks human explorers will actually perform, and how robots can best assist them, is to have human explorers and scientists go and explore in an outdoor, planetary-relevant environment, with robots to demonstrate what they are capable of, and roboticists to observe the results. It can be difficult to have a human expert itemize all the needed tasks required for exploration while sitting in a lab: humans do not always remember all the details, and experts in one arena may not even recognize that the lower level tasks they take for granted may be essential for a roboticist to know about. Field tests thus create conditions that more accurately reveal missing components and invalid assumptions, as well as allow tests and comparisons of new approaches and demonstrations of working systems. We have performed field tests in our local rock yard, in several locations in the Arizona desert, and in the Utah desert. We have tested multiple exploration scenarios, such as geological traverses, cable or solar panel deployments, and science instrument deployments. The configuration of our robot can be changed, based on what equipment is needed for a given scenario, and the sensor mast can even be placed on one of two robot bases, each with different motion capabilities. The software architecture of our robot is also designed to be as modular as possible, to allow for hardware and configuration changes. Two focus

  19. Developing Zircon as a Probe of Planetary Impact History

    Science.gov (United States)

    Wielicki, Matthew

    2014-12-01

    The identification of Meteor Crater in Arizona as an extraterrestrial impact by Eugene Shoemaker provided the first evidence of this geologic phenomenon and opened the door to a new field of research that has eventually lead to the identification of over ~150 terrestrial impact structures. Subsequently impacts have been evoked in the formation of the moon, delivery of volatiles and bio-precursors to early Earth, creation of habitats for the earliest life and, in more recent times, major mass extinction events. However, understanding the impact flux to the Earth-Moon system has been complicated by the constant weathering and erosion at Earth's surface and the complex nature of impactite samples such that only a hand full of terrestrial craters have been accurately and precisely dated. Currently 40Ar/39Ar step-heating analysis of impactite samples is commonly used to infer impact ages but can be problematic due to the presence of relic clasts, incomplete 40Ar outgassing or excess 40Ar, and recoil and shock effects. The work presented here attempts to develop zircon geochronology to probe planetary impact histories as an alternative to current methods and provides another tool by which to constrain the bolide flux to the Earth-Moon system. Zircon has become the premier geo-chronometer in earth science and geochemical investigation of Hadean zircon from Western Australia has challenged the long-standing, popular conception that the near-surface Hadean Earth was an uninhabitable and hellish world; Zircons may preserve environmental information regarding their formation and thus provide a rare window into conditions on early Earth. Isotopic and petrologic analyses of these ancient grains have been interpreted to suggest that early Earth was more habitable than previously envisioned, with water oceans, continental crust, and possibly even plate tectonics. The Hadean is also suspected to be a time of major planetary bombardment however identifying impact signatures within

  20. Testing the Planet-Metallicity Correlation in M-dwarfs with Gemini GNIRS Spectra

    Science.gov (United States)

    Hobson, M. J.; Jofré, E.; García, L.; Petrucci, R.; Gómez, M.

    2018-04-01

    While the planet-metallicity correlation for FGK main-sequence stars hosting giant planets is well established, it is less clear for M-dwarf stars. We determine stellar parameters and metallicities for 16 M-dwarf stars, 11 of which host planets, with near-infrared spectra from the Gemini Near-Infrared Spectrograph (GNIRS). We find that M-dwarfs with planets are preferentially metal-rich compared to those without planets. This result is supported by the analysis of a larger catalogue of 18 M stars with planets and 213 M stars without known planets T15, and demonstrates the utility of GNIRS spectra to obtain reliable stellar parameters of M stars. We also find that M dwarfs with giant planets are preferentially more metallic than those with low-mass planets, in agreement with previous results for solar-type stars. These results favor the core accretion model of planetary formation.

  1. No Photon Left Behind: How Billions of Spectral Lines are Transforming Planetary Sciences

    Science.gov (United States)

    Villanueva, Geronimo L.

    2014-06-01

    With the advent of realistic potential energy surface (PES) and dipole moment surface (DMS) descriptions, theoretically computed linelists can now synthesize accurate spectral parameters for billions of spectral lines sampling the untamed high-energy molecular domain. Being the initial driver for these databases the characterization of stellar spectra, these theoretical databases, in combination with decades of precise experimental studies (nicely compiled in community databases such as HITRAN and GEISA), are leading to unprecedented precisions in the characterization of planetary atmospheres. Cometary sciences are among the most affected by this spectroscopic revolution. Even though comets are relatively cold bodies (T˜100 K), their infrared molecular emission is mainly defined by non-LTE solar fluorescence induced by a high-energy source (Sun, T˜5600 K). In order to interpret high-resolution spectra of comets acquired with extremely powerful telescopes (e.g., Keck, VLT, NASA-IRTF), we have developed advanced non-LTE fluorescence models that integrate the high-energy dynamic range of ab-initio databases (e.g., BT2, VTT, HPT2, BYTe, TROVE) and the precision of laboratory and semi-empirical compilations (e.g., HITRAN, GEISA, CDMS, WKMC, SELP, IUPAC). These new models allow us to calculate realistic non-LTE pumps, cascades, branching-ratios, and emission rates for a broad range of excitation regimes for H2O, HDO, HCN, HNC and NH3. We have implemented elements of these compilations to the study of Mars spectra, and we are now exploring its application to modeling non-LTE emission in exoplanets. In this presentation, we present application of these advanced models to interpret highresolution spectra of comets, Mars and exoplanets.

  2. Scikit-spectra: Explorative Spectroscopy in Python

    Directory of Open Access Journals (Sweden)

    Adam Hughes

    2015-06-01

    Full Text Available Scikit-spectra is an intuitive framework for explorative spectroscopy in Python. Scikit-spectra leverages the Pandas library for powerful data processing to provide datastructures and an API designed for spectroscopy. Utilizing the new IPython Notebook widget system, scikit-spectra is headed towards a GUI when you want it, API when you need it approach to spectral analysis. As an application, analysis is presented of the surface-plasmon resonance shift in a solution of gold nanoparticles induced by proteins binding to the gold’s surface. Please refer to the scikit-spectra website for full documentation and support: http://hugadams.github.io/scikit-spectra/

  3. Day-to-day migrating and nonmigrating tidal variability due to the six-day planetary wave

    Science.gov (United States)

    Pedatella, N. M.; Liu, H.-L.; Hagan, M. E.

    2012-06-01

    To investigate day-to-day variability in the mesosphere and lower thermosphere (MLT), an idealized simulation of a six-day westward propagating zonal wave number-1 planetary wave is performed using the National Center for Atmospheric Research (NCAR) Thermosphere-Ionosphere-Mesosphere-Electrodynamics General Circulation Model (TIME-GCM). The six-day planetary wave introduces a six-day periodicity in the zonal mean atmosphere, migrating and nonmigrating tides, as well as in secondary waves that are produced by nonlinear planetary wave-tide interactions. We have further used the linear Global Scale Wave Model (GSWM) to isolate the effect of how the day-to-day changes in zonal mean zonal winds may influence tides in the MLT. The most significant changes are observed in the migrating diurnal tide (DW1), eastward propagating nonmigrating tides with zonal wave numbers-2 and -3 (DE2 and DE3), and a 20 hr eastward propagating wave with zonal wave number-2 (20E2). Because we have included the lower atmospheric source of nonmigrating tides, DE2 and DE3 are present with relatively large amplitudes in the MLT, even in the absence of planetary wave forcing. The 20E2 wave is produced by the nonlinear interaction between the DE3 and the six-day planetary wave, and its large amplitude indicates the importance of including the realistic spectra of nonmigrating tides in numerical simulations of planetary waves. The GSWM simulations reveal that the DW1 is not significantly influenced by the changes in the zonal mean winds. We thus conclude that the DW1 changes are driven by a combination of changes due to nonlinear interaction with the six-day planetary wave as well as changes due to zonal asymmetries that result from the six-day planetary wave. The six-day planetary wave induced changes in zonal mean zonal winds lead to a general reduction in the amplitude of DE2 and DE3, and introduce a slight periodic behavior in these tides. The effect of changing zonal mean zonal winds appears to

  4. INFLUENCE OF STELLAR FLARES ON THE CHEMICAL COMPOSITION OF EXOPLANETS AND SPECTRA

    Energy Technology Data Exchange (ETDEWEB)

    Venot, Olivia; Decin, Leen [Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, Celestijnenlaan 200D, B-3001 Leuven (Belgium); Rocchetto, Marco [University College London, Department of Physics and Astronomy, Gower Street, London WC1E 6BT (United Kingdom); Carl, Shaun; Hashim, Aysha Roshni, E-mail: olivia.venot@kuleuven.be [Department of Quantum Chemistry and Physical Chemistry, Katholieke Universiteit Leuven, Celestijnenlaan 200F, B-3001 Leuven (Belgium)

    2016-10-20

    More than three thousand exoplanets have been detected so far, and more and more spectroscopic observations of exoplanets are performed. Future instruments ( James Webb Space Telescope ( JWST ), E-ELT, PLATO, Ariel, etc.,) are eagerly awaited, as they will be able to provide spectroscopic data with greater accuracy and sensitivity than what is currently available. This will allow more accurate conclusions to be drawn regarding the chemistry and dynamics of exoplanetary atmospheres, provided that the observational data are carefully processed. One important aspect to consider is temporal stellar atmospheric disturbances that can influence the planetary composition, and hence spectra, and potentially can lead to incorrect assumptions about the steady-state atmospheric composition of the planet. In this paper, we focus on perturbations coming from the host star in the form of flare events that significantly increase photon flux impingement on the exoplanets atmosphere. In some cases, particularly for M stars, this sudden increase may last for several hours. We aim to discover to what extent a stellar flare is able to modify the chemical composition of the planetary atmosphere and, therefore, influence the resulting spectra. We use a one-dimensional thermo-photochemical model to study the neutral atmospheric composition of two hypothetical planets located around the star AD Leo. We place the two planets at different distances from the star, which results in effective atmospheric temperatures of 412 and 1303 K. AD Leo is an active star that has already been observed during a flare. Therefore, we use the spectroscopic data from this flare event to simulate the evolution of the chemical composition of the atmospheres of the two hypothetical planets. We compute synthetic spectra to evaluate the implications for observations. The increase in the incoming photon flux affects the chemical abundances of some important species (such as H and NH{sub 3}), down to altitudes

  5. Adaptive bio-inspired navigation for planetary exploration, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Surface exploration of planetary environments with current robotic technologies relies heavily on human control and power-hungry active sensors to perform even the...

  6. Multi-Robot Systems for Subsurface Planetary Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed innovation is a heterogeneous multi-robot team developed as a platform for effective subsurface planetary exploration. State-of-art robotic exploration...

  7. Sensor Array Analyzer for Planetary Exploration, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Future planetary exploration missions such as those planned by NASA and other space agencies over the next few decades require advanced chemical and biological...

  8. Planetary-Whigs: Optical MEMS-Based Seismometer, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — During this Phase I, Michigan Aerospace Corporation will adapt the design of an optical MEMS seismometer for lunar and other planetary science instrumentation. The...

  9. Nonlinear time heteronymous damping in nonlinear parametric planetary systems

    Czech Academy of Sciences Publication Activity Database

    Hortel, Milan; Škuderová, Alena

    2014-01-01

    Roč. 225, č. 7 (2014), s. 2059-2073 ISSN 0001-5970 Institutional support: RVO:61388998 Keywords : nonlinear dynamics * planetary systems * heteronymous damping Subject RIV: JT - Propulsion, Motors ; Fuels Impact factor: 1.465, year: 2014

  10. Cathodoluminescence and its application in the planetary sciences

    CERN Document Server

    Gucsik, Arnold

    2009-01-01

    This book provides an overview of cathodoluminescence properties of the planetary materials. It provides a unique introduction to cathodoluminescence which is widely used in the geosciences, because it is a non-destructive and "easy to use" method.

  11. HST WIDE FIELD PLANETARY CAMERA 2 OBSERVATIONS OF MARS

    Data.gov (United States)

    National Aeronautics and Space Administration — The Hubble Space Telescope Wide Field Planetary Camera 2 data archive contains calibrated data of Mars observed between April 27, 1999 and September 4, 2001. These...

  12. Young planetary nebula with OH molecules - NGC 6302

    International Nuclear Information System (INIS)

    Payne, H.E.; Phillips, J.A.; Terzian, Y.

    1988-01-01

    The results of a sensitive survey of planetary nebulae in all four ground-state OH lines are reported. The results confirm that evolved planetary nebulas are not OH sources in general. However, one interesting object was not detected: an OH 1612 MHz maser in the young planetary nebula NGC 6302. This nebula may be in a brief evolutionary stage, similar to the young and compact planetary nebula Vy 2-2, where OH has already been detected. In addition, the results of further observations of NGC 6302 are reported, including VLA observations of the 1612 MHz line and continuum emission and detections of rotationally excited OH lines at 5-cm wavelength in absorption. 28 references

  13. One-Meter Class Drilling for Planetary Exploration, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Robotic planetary exploration missions will need to perform in-situ analysis of rock and/or regolith samples or returning samples back to earth. Obtaining and...

  14. 'Planetary boundaries’ — exploring the challenges for global environmental governance

    NARCIS (Netherlands)

    Galaz, V.; Biermann, F.; Crona, B.; Loorbach, D.; Folke, C.; Olsson, P.; Nilsson, M.; Allouche, J.; Persson, Å.; Reischl, G.

    2012-01-01

    A range of studies from Earth system scientists argue that human activities drive multiple, interacting effects that cascade through the Earth system. Recent contributions state and quantify nine, interacting 'planetary boundaries' with possible threshold effects. This article provides an overview

  15. Low-energy Planetary Excavator (LPE), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — ORBITEC proposes to develop an innovative Low-energy Planetary Excavator (LPE) to excavate in situ regolith, ice-regolith mixes, and a variety of other geologic...

  16. Low-energy Planetary Excavator (LPE), Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — ORBITEC is developing an innovative Low-energy Planetary Excavator (LPE) to excavate in situ regolith, ice-regolith mixes, and a variety of other geologic materials...

  17. Planetary Vacuum Cleaner for Venus and Mars, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The majority of planetary bodies of interest to exploration are covered with a layer of granular material called regolith. These bodies include the Moon, Mercury,...

  18. Highly Efficient Compact Laser for Planetary Exploration, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — In response to the solicitation for advances in critical components of instruments for enhanced scientific investigations on future planetary mission, Q-Peak...

  19. Relation between radius and expansion velocity in planetary nebulae

    International Nuclear Information System (INIS)

    Chu, Y.H.; Kwitter, K.B.; Kaler, J.B.

    1984-01-01

    The expansion velocity-radius (R-V) relation for planetary nebulae is examined using the existing measurements of expansion velocities and recent calculations of radii. It is found that some of the previously alleged R-V relations for PN are not convincingly established. The scatter in the R-V plots may be due largely to stratification of ions in individual nebulae and to heterogeneity in the planetary nebula population. In addition, from new echelle/CCD observations of planetary nebulae, it is found that spatial information is essential in deriving the internal kinematic properties. Future investigations of R-V relations should be pursued separately for groups of planetaries with similar physical properties, and they should employ observations of appropriate low excitation lines in order to measure the expansion velocity at the surface of the nebula. 26 references

  20. Measuring and interpreting X-ray fluorescence from planetary surfaces.

    Science.gov (United States)

    Owens, Alan; Beckhoff, Burkhard; Fraser, George; Kolbe, Michael; Krumrey, Michael; Mantero, Alfonso; Mantler, Michael; Peacock, Anthony; Pia, Maria-Grazia; Pullan, Derek; Schneider, Uwe G; Ulm, Gerhard

    2008-11-15

    As part of a comprehensive study of X-ray emission from planetary surfaces and in particular the planet Mercury, we have measured fluorescent radiation from a number of planetary analog rock samples using monochromatized synchrotron radiation provided by the BESSY II electron storage ring. The experiments were carried out using a purpose built X-ray fluorescence (XRF) spectrometer chamber developed by the Physikalisch-Technische Bundesanstalt, Germany's national metrology institute. The XRF instrumentation is absolutely calibrated and allows for reference-free quantitation of rock sample composition, taking into account secondary photon- and electron-induced enhancement effects. The fluorescence data, in turn, have been used to validate a planetary fluorescence simulation tool based on the GEANT4 transport code. This simulation can be used as a mission analysis tool to predict the time-dependent orbital XRF spectral distributions from planetary surfaces throughout the mapping phase.

  1. Magnetoshell Aerocapture for Manned Missions and Planetary Deep Space Orbiters

    Data.gov (United States)

    National Aeronautics and Space Administration — It is clear from past mission studies that a manned Mars mission, as well as deep space planetary orbiters will require aerobraking and aerocapture which use...

  2. SPEX : An in-orbit spectropolarimeter for planetary exploration

    NARCIS (Netherlands)

    Snik, F.; Karalidi, T.; Keller, C.; Laan, E.; Ter Horst, R.; Navarro, R.; Stam, D.; Aas, C.; De Vries, J.

    2008-01-01

    SPEX (Spectropolarimeter for Planetary EXploration) is an innovative, compact remote-sensing instrument for detecting and characterizing aerosols. With its 1-liter volume it is capable of full linear spectropolarimetry, without moving parts. High precision polarimetry is performed through encoding

  3. Adaptive bio-inspired navigation for planetary exploration, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Exploration of planetary environments with current robotic technologies relies on human control and power-hungry active sensors to perform even the most elementary...

  4. Mars & Multi-Planetary Electrical Environment Spectrum Analyzer

    Data.gov (United States)

    National Aeronautics and Space Administration — In FY14, we will develop and deliver a Multi-Planetary Electrical Environment Plasma Spectrum Analyzer. This instrument is a DC and AC electric field sensor suite...

  5. The Lunar and Planetary Institute Summer Intern Program in Planetary Science

    Science.gov (United States)

    Kramer, G. Y.

    2017-12-01

    Since 1977, the Lunar and Planetary Institute (LPI) Summer Intern Program brings undergraduate students from across the world to Houston for 10 weeks of their summer where they work one-on-one with a scientist at either LPI or Johnson Space Center on a cutting-edge research project in the planetary sciences. The program is geared for students finishing their sophomore and junior years, although graduating seniors may also apply. It is open to international undergraduates as well as students from the United States. Applicants must have at least 50 semester hours of credit (or equivalent sophomore status) and an interest in pursuing a career in the sciences. The application process is somewhat rigorous, requiring three letters of recommendation, official college transcripts, and a letter describing their background, interests, and career goals. The deadline for applications is in early January of that year of the internship. More information about the program and how to apply can be found on the LPI website: http://www.lpi.usra.edu/lpiintern/. Each advisor reads through the applications, looking for academically excellent students and those with scientific interest and backgrounds compatible with the advisor's specific project. Interns are selected fairly from the applicant pool - there are no pre-arranged agreements or selections based on who knows whom. The projects are different every year as new advisors come into the program, and existing ones change their research interest and directions. The LPI Summer Intern Program gives students the opportunity to participate in peer-reviewed research, learn from top-notch planetary scientists, and preview various careers in science. For many interns, this program was a defining moment in their careers - when they decided whether or not to follow an academic path, which direction they would take, and how. While past interns can be found all over the world and in a wide variety of occupations, all share the common bond of

  6. Different spectra with the same neutron source

    Energy Technology Data Exchange (ETDEWEB)

    Vega C, H. R.; Ortiz R, J. M.; Hernandez D, V. M.; Martinez B, M. R.; Hernandez A, B.; Ortiz H, A. A. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Mercado, G. A., E-mail: fermineutron@yahoo.co [Universidad Autonoma de Zacatecas, Unidad Academica de Matematicas, Jardin Juarez No. 147, 98000 Zacatecas (Mexico)

    2010-02-15

    Using as source term the spectrum of a {sup 239}Pu-Be source several neutron spectra have been calculated using Monte Carlo methods. The source term was located in the centre of spherical moderators made of light water, heavy water and polyethylene of different diameters. Also a {sup 239}Pu-Be source was used to measure its neutron spectrum, bare and moderated by water. The neutron spectra were measured at 100 cm with a Bonner spheres spectrometer. Monte Carlo calculations were used to calculate the neutron spectra of bare and water-moderated spectra that were compared with those measured with the spectrometer. Resulting spectra are similar to those found in power plants with PWR, BWR and Candu nuclear reactors. Beside the spectra the dosimetric features were determined. Using moderators and a single neutron source can be produced neutron spectra alike those found in workplaces, this neutron fields can be utilized to calibrate neutron dosimeters and area monitors. (Author)

  7. Different spectra with the same neutron source

    International Nuclear Information System (INIS)

    Vega C, H. R.; Ortiz R, J. M.; Hernandez D, V. M.; Martinez B, M. R.; Hernandez A, B.; Ortiz H, A. A.; Mercado, G. A.

    2010-01-01

    Using as source term the spectrum of a 239 Pu-Be source several neutron spectra have been calculated using Monte Carlo methods. The source term was located in the centre of spherical moderators made of light water, heavy water and polyethylene of different diameters. Also a 239 Pu-Be source was used to measure its neutron spectrum, bare and moderated by water. The neutron spectra were measured at 100 cm with a Bonner spheres spectrometer. Monte Carlo calculations were used to calculate the neutron spectra of bare and water-moderated spectra that were compared with those measured with the spectrometer. Resulting spectra are similar to those found in power plants with PWR, BWR and Candu nuclear reactors. Beside the spectra the dosimetric features were determined. Using moderators and a single neutron source can be produced neutron spectra alike those found in workplaces, this neutron fields can be utilized to calibrate neutron dosimeters and area monitors. (Author)

  8. Accounting for planet-shaped planetary nebulae

    Science.gov (United States)

    Sabach, Efrat; Soker, Noam

    2018-01-01

    By following the evolution of several observed exoplanetary systems, we show that by lowering the mass-loss rate of single solar-like stars during their two giant branches, these stars will swallow their planets at the tip of their asymptotic giant branch (AGB) phase. This will most likely lead the stars to form elliptical planetary nebulae (PNe). Under the traditional mass-loss rate these stars will hardly form observable PNe. Stars with a lower mass-loss rate as we propose, about 15 per cent of the traditional mass-loss rate of single stars, leave the AGB with much higher luminosities than what traditional evolution produces. Hence, the assumed lower mass-loss rate might also account for the presence of bright PNe in old stellar populations. We present the evolution of four exoplanetary systems that represent stellar masses in the range of 0.9-1.3 M⊙. The justification for this low mass-loss rate is our assumption that the stellar samples that were used to derive the traditional average single-star mass-loss rate were contaminated by stars that suffer binary interaction.

  9. Electrostatic Dust Control on Planetary Surfaces

    Science.gov (United States)

    Clark, P. E.; Calle, C. I.; Curtis, S. A.; Keller, J. F.; Minetto, F.; Mantovani, J. G.

    2007-01-01

    Successful operation for exploration of planetary regoliths will depend on the capability to keep surfaces free of dust which could compromise performance and to collect dust for characterization. Such study is essential in order to resolve issues in dealing with regolith fines identified during the Apollo missions where dust behaved like abrasive Velcro before returning to the Moon. During Moon landings, locally-induced stirring of the regolith caused dust to be suspended long enough to come into contact with conducting surfaces. Lunar fines, because of their electrostatic charging, were difficult to collect and sparsely sampled: bag seals were broken, samples contaminated and lost. Our objectives here are to describe a multi-faceted electrostatically-based approach and methodology for addressing this issue, as well as to present our preliminary results which confirm the view that the successful strategy will deal with dust dynamics resulting from interaction between mechanical and electrostatic forces. Our device concept combines electron or ion beams, acting as a plasma dust sweeper to control the flow of dust by systematic scanning of the surface with an electrostatically controlled potential. A plate of the opposite potential used to induce dust migration in the presence of an electrical field. Our goal is a compact device of dust for sampling as part of the extended exploration process on extensive areas of exposed impact-generated regolith, on Mercury, Mars, asteroids or outer solar system satellites, as well as the Moon.

  10. Planetary vistas the landscapes of other worlds

    CERN Document Server

    Murdin, Paul

    2015-01-01

    The word “landscape” can mean picture as well as natural scenery. Recent advances in space exploration imaging have allowed us to now have landscapes never before possible, and this book collects some of the greatest views and vistas of Mars, Venus’s Titan, Io and more in their full glory, with background information to put into context the foreign landforms of our Solar System. Here, literally, are 'other-worldly' visions of strange new scenes, all captured by the latest technology by landing and roving vehicles or by very low-flying spacecraft.   There is more than scientific interest in these views. They are also aesthetically beautiful and intriguing, and Dr. Murdin in a final chapter compares them to terrestrial landscapes in fine art.   Planetary Vistas is a science book and a travel book across the planets and moons of the Solar System for armchair space explorers who want to be amazed and informed. This book shows what future space explorers will experience, because these are the landscapes th...

  11. Evolutionary sequence of models of planetary nebulae

    International Nuclear Information System (INIS)

    Vil'koviskij, Eh.Ya.; Kondrat'eva, L.N.; Tambovtseva, L.V.

    1983-01-01

    The evolutionary sequences of model planetary nebulae of different masses have been calculated. The computed emission line intensities are compared with the observed ones by means of the parameter ''reduced size of the nebula'', Rsub(n). It is shown that the evolution tracks of Schonberner for the central stars are consistent with the observed data. Part of ionized mass Mi in any nebulae does not not exceed 0.3 b and in the average Msu(i) 3 years at actual values of radius Rsub(i) <0.025 ps. Then the luminosity growth slows down to the maximum temperature which central star reaches and decreases with sharp decrease of the star luminosity. At that, the radius of ionized zone of greater mass nebulae can even decrease, inspite of the constant expansion of the nebula. As a result nebulae of great masses having undergone the evolution can be included in the number of observed compact objects (Rsub(n) < 0.1 ps)

  12. Lunar and planetary cartography in Russia

    CERN Document Server

    Shevchenko, Vladislav; Michael, Gregory

    2016-01-01

    This book is the first to document in depth the history of lunar and planetary cartography in Russia. The first map of the far side of the Moon was made with the participation of Lomonosov Moscow University (Sternberg Astronomical Institute, MSU) in 1960. The developed mapping technologies were then used in preparing the “Complete Map of the Moon” in 1967 as well as other maps and globes. Over the years, various maps of Mars have emerged from the special course “Mapping of extraterrestrial objects” in the MSU Geography Department, including the hypsometric map of Mars at a scale of 1:26,000,000, compiled by J.A. Ilyukhina and published in 2004 in an edition of 5,000 copies. A more detailed version of this map has since been produced with a new hypsometric scale. In addition, maps of the northern and southern hemispheres of Mars have been compiled for the hypsometric globe of Mars.  Relief maps of Venus were made in 2008, 2010, and 2011, and hypsometric maps of Phobos and Deimos at a scale of 1:60,000...

  13. Global Magnetic Variability at Planetary Wave Periods

    Science.gov (United States)

    Forbes, J. M.; Behm, J.

    2017-12-01

    Planetary waves (PW) and PW-tide interactions are thought to introduce multi-day periodicities ( 2-20 days) in the electric fields and currents induced by the wind dynamo mechanism in the ionospheric E-region (ca. 100-150 km), and thus can provide important insights on coupling between the lower atmosphere and the ionosphere. Previous studies have used a relatively small subset of available data to infer the existence of these variations in ground magnetic measurements. In some cases connections were made with contemporaneous measurements of neutral wind dynamics. In the present work, we employ ground-based magnetometer data from over 100 stations from the INTERMAGNET network during 2009 to gain a global perspective on eastward- and westward-propagating and zonally-symmetric oscillations with PW periods. Our presentation describes how the unevenly-spaced global data are re-gridded onto an icosahedral grid prior to analysis, and assesses how gaps in the distribution of points across the grid affect extraction of some parts of the spectrum. Consideration is also given to possible contamination by recurrent magnetic activity at subharmonics of 27 days. The global evolution of several PW components during 2009 are depicted and interpreted.

  14. Planetary Environments: Scientific Issues and Perspectives

    Directory of Open Access Journals (Sweden)

    Encrenaz Th.

    2014-02-01

    Full Text Available What are the planetary environments where conditions are best suited for habitability? A first constraint is provided by the presence of liquid water. This condition allows us to define two kinds of media: (1 the atmospheres of solid (exoplanets with a temperature typically ranging between 0°C and 100°C, and (2 the interiors of icy bodies (outer satellites or possibly exosatellites where the pressure and temperature would fit the liquid phase region of the water phase diagram. In the case of Mars, significant progress has been achieved about our understanding of the history of liquid water in the past, thanks to the findings of recent space missions. The study of the outer satellites is also benefiting from the on-going operation of the Cassini mission. In the case of exopl nets, new discoveries are continuously reported, especially with the Kepler mission, in operation since 2009. With the emergence of transit spectroscopy, a new phase of exoplanets’ exploration has started, their characterization, opening the new field of exoplanetology. In the future, new perspectives appear regarding the exploration of Mars, the giant planets and exoplanets, with the ultimate goal of characterizing the atmospheres of temperate exoplanets.

  15. Ups and downs in planetary science

    Science.gov (United States)

    Shoemaker, Carolyn S.

    1999-01-01

    The field of planetary science as it developed during the lifetimes of Gene and Carolyn Shoemaker has sustained a period of exciting growth. Surveying the skies for planet-crossing asteroids and comets and studying the results of their impact upon the planets, especially the Earth, was for Gene and Carolyn an intense and satisfying quest for knowledge. It all started when Gene envisioned man going to the Moon, especially himself. After that, one thing led to another: the study of nuclear craters and a comparison with Meteor Crater, Arizona; the Apollo project and a succession of unmanned space missions to the inner and outer planets; an awareness of cratering throughout our solar system; the search for near-Earth asteroids and comets; a study of ancient craters in Australia; and the impact of Shoemaker-Levy 9 on Jupiter. The new paradigm of impact cratering as a cause for mass extinction and the opening of space for the development of new life forms have been causes to champion.

  16. Applications of Nanosats to Planetary Exploration

    Science.gov (United States)

    Klesh, Andrew T.; Castillo-Rogez, Julie C.

    2012-01-01

    NanoSat technology has opened Earth orbit to extremely low-cost science missions through a common interface that provides greater launch accessibility. A natural question is the role that CubeSat-derived NanoSats could play to increase the science return of deep space missions. We do not consider single instrument nano-satellites as likely to complete entire Discovery-class missions alone, but believe that nano-satellites could augment larger missions to significantly increase science return. The key advantages offered by these mini-spacecrafts over previous planetary probes is the common availability of advanced subsystems that open the door to a large variety of science experiments, including new guidance, navigation and control capabilities. In this paper, multiple NanoSat science applications are suggested that could take advantage of these features. We also address the significant challenges and questions that remain as obstacles to the use of nano-satellites in deep space missions. Finally, we provide some thoughts on a development roadmap toward interplanetary usage of NanoSpacecraft.

  17. Multi-angular regolith effects on planetary soft X-ray fluorescence spectroscopy

    Science.gov (United States)

    Näränen, J.; Parviainen, H.; Carpenter, J.; Muinonen, K.

    2009-04-01

    Fluorescent X-rays from the surfaces of airless planetary bodies in the inner solar system have been measured by instruments on several spacecraft. MESSENGER carries an X-ray spectrometer (XRS) on-board and has already attempted to obtain fluorescent X-rays from the Hermean surface. BepiColombo will later on carry an X-ray telescope (MIXS-T) along with a more conventional collimating detector (MIXS-C) to the Hermean orbit, supported by a next-generation X-ray solar monitor (SIXS). These instruments will provide unprecedented knowledge about the geochemical properties of the Hermean regolith. X-ray emission from planetary surfaces follows photoionisation by incident solar X-rays and charged particles and reveals information about the elemental composition of the surface. Analyses of X-ray spectra, obtained by orbiting spacecraft, use both the relative intensities of elemental emission lines (e.g., Ca/Si, Fe/Si) and absolute abundancies of the elements to determine the geochemistry of the target body. Historically, the analysis of X-ray spectra has largely assumed that surfaces can be considered as homogeneous plane-parallel media. It has been shown, however, that fluorescent line intensities are affected by the physical properties of the target surface (e.g., surface roughness of the regolith) as a function of the viewing and illumination geometry of observations in a way that cannot be explained by the traditional models. We describe experimental investigations where we simulated the effects of regolith properties on the fluorescent lines measured by an orbiting instrument, with a large variety of illumination and viewing angles. The planetary regolith analogue used in these experiments was a terrestrial, olivine rich basalt, which has been used by previous authors as an analogue to the lunar maria. The basalt samples were ground to powder and sieved to discriminate particles in the ranges, powders were then pressed into solid pellets. The separation of particles

  18. Planetary Space Weather Services for the Europlanet 2020 Research Infrastructure

    Science.gov (United States)

    André, Nicolas; Grande, Manuel

    2016-04-01

    Under Horizon 2020, the Europlanet 2020 Research Infrastructure (EPN2020-RI) will include an entirely new Virtual Access Service, WP5 VA1 "Planetary Space Weather Services" (PSWS) that will extend the concepts of space weather and space situational awareness to other planets in our Solar System and in particular to spacecraft that voyage through it. VA1 will make five entirely new 'toolkits' accessible to the research community and to industrial partners planning for space missions: a general planetary space weather toolkit, as well as three toolkits dedicated to the following key planetary environments: Mars (in support ExoMars), comets (building on the expected success of the ESA Rosetta mission), and outer planets (in preparation for the ESA JUICE mission to be launched in 2022). This will give the European planetary science community new methods, interfaces, functionalities and/or plugins dedicated to planetary space weather in the tools and models available within the partner institutes. It will also create a novel event-diary toolkit aiming at predicting and detecting planetary events like meteor showers and impacts. A variety of tools (in the form of web applications, standalone software, or numerical models in various degrees of implementation) are available for tracing propagation of planetary and/or solar events through the Solar System and modelling the response of the planetary environment (surfaces, atmospheres, ionospheres, and magnetospheres) to those events. But these tools were not originally designed for planetary event prediction and space weather applications. So WP10 JRA4 "Planetary Space Weather Services" (PSWS) will provide the additional research and tailoring required to apply them for these purposes. The overall objectives of this Joint Research Aactivities will be to review, test, improve and adapt methods and tools available within the partner institutes in order to make prototype planetary event and space weather services operational in

  19. Novel Space Exploration Technique for Analysing Planetary Atmospheres

    OpenAIRE

    Dekoulis, George

    2010-01-01

    The chapter presents a new reconfigurable wide-beam radio interferometer system for analysing planetary atmospheres. The system operates at frequencies, where the ionisation of the planetary plasma regions induces strong attenuation. For Earth, the attenuation is undistinguishable from the CMB at frequencies over 50 MHz. The system introduces a set of advanced specifications to this field of science, previously unseen in similar suborbital experiments. The reprogrammable dynamic range of the ...

  20. Smart Rotorcraft Field Assistants for Terrestrial and Planetary Science

    Science.gov (United States)

    Young, Larry A.; Aiken, Edwin W.; Briggs, Geoffrey A.

    2004-01-01

    Field science in extreme terrestrial environments is often difficult and sometimes dangerous. Field seasons are also often short in duration. Robotic field assistants, particularly small highly mobile rotary-wing platforms, have the potential to significantly augment a field season's scientific return on investment for geology and astrobiology researchers by providing an entirely new suite of sophisticated field tools. Robotic rotorcraft and other vertical lift planetary aerial vehicle also hold promise for supporting planetary science missions.

  1. Void Points, Rosettes, and a Brief History of Planetary Astronomy

    Science.gov (United States)

    Kosso, Peter

    2013-12-01

    Almost all models of planetary orbits, from Aristotle through Newton, include void points, empty points in space that have an essential role in defining the orbit. By highlighting the role of these void points, as well as the rosette pattern of the orbit that often results, I bring out different features in the history of planetary astronomy and place a different emphasis on its revolutionary changes, different from those rendered in terms of epicycles or the location of the earth.

  2. Image Processing for Planetary Limb/Terminator Extraction

    Science.gov (United States)

    Udomkesmalee, S.; Zhu, D. Q.; Chu, C. -C.

    1995-01-01

    A novel image segmentation technique for extracting limb and terminator of planetary bodies is proposed. Conventional edge- based histogramming approaches are used to trace object boundaries. The limb and terminator bifurcation is achieved by locating the harmonized segment in the two equations representing the 2-D parameterized boundary curve. Real planetary images from Voyager 1 and 2 served as representative test cases to verify the proposed methodology.

  3. Planetary cartography in the next decade (1984 - 1994)

    Science.gov (United States)

    1984-01-01

    The cartographic products required to support science and planetary exploration during the next 10 years were assessed. Only major map series or first order maps needed to characterize the surface physiography of a planet or satellite were considered. Included in these considerations are maps needed as bases for plotting geologic, geophysical, and atmospheric phenomena and for planning future planetary exploration. These products consist of three types of maps: controlled photomosaics, shaded relief maps, and topographic contour maps.

  4. Visualization of Kepler’s laws of planetary motion

    Science.gov (United States)

    Lu, Meishu; Su, Jun; Wang, Weiguo; Lu, Jianlong

    2017-03-01

    For this article, we use a 3D printer to print a surface similar to universal gravitation for demonstrating and investigating Kepler’s laws of planetary motion describing the motion of a small ball on the surface. This novel experimental method allows Kepler’s laws of planetary motion to be visualized and will contribute to improving the manipulative ability of middle school students and the accessibility of classroom education.

  5. Graviton spectra in string cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Galluccio, Massimo [Osservatorio Astronomico di Roma (Roma-IT); Litterio, Marco [Istituto Astronomico dell' Universita (Roma-IT); Occhionero, Franco [Osservatorio Astronomico di Roma (Roma-IT)

    1996-08-01

    We propose to uncover the signature of a stringy era in the primordial Universe by searching for a prominent peak in the relic graviton spectrum. This feature, which in our specific model terminates an ω³ increase and initiates an ω⁻⁷ decrease, is induced during the so far overlooked bounce of the scale factor between the collapsing deflationary era (or pre-Big Bang) and the expanding inflationary era (or post-Big Bang). We evaluate both analytically and numerically the frequency and the intensity of the peak and we show that they may likely fall in the realm of the new generation of interferometric detectors. The existence of a peak is at variance with ordinarily monotonic (either increasing or decreasing) graviton spectra of canonical cosmologies; its detection would therefore offer strong support to string cosmology.

  6. Interoperability in planetary research for geospatial data analysis

    Science.gov (United States)

    Hare, Trent M.; Rossi, Angelo P.; Frigeri, Alessandro; Marmo, Chiara

    2018-01-01

    For more than a decade there has been a push in the planetary science community to support interoperable methods for accessing and working with geospatial data. Common geospatial data products for planetary research include image mosaics, digital elevation or terrain models, geologic maps, geographic location databases (e.g., craters, volcanoes) or any data that can be tied to the surface of a planetary body (including moons, comets or asteroids). Several U.S. and international cartographic research institutions have converged on mapping standards that embrace standardized geospatial image formats, geologic mapping conventions, U.S. Federal Geographic Data Committee (FGDC) cartographic and metadata standards, and notably on-line mapping services as defined by the Open Geospatial Consortium (OGC). The latter includes defined standards such as the OGC Web Mapping Services (simple image maps), Web Map Tile Services (cached image tiles), Web Feature Services (feature streaming), Web Coverage Services (rich scientific data streaming), and Catalog Services for the Web (data searching and discoverability). While these standards were developed for application to Earth-based data, they can be just as valuable for planetary domain. Another initiative, called VESPA (Virtual European Solar and Planetary Access), will marry several of the above geoscience standards and astronomy-based standards as defined by International Virtual Observatory Alliance (IVOA). This work outlines the current state of interoperability initiatives in use or in the process of being researched within the planetary geospatial community.

  7. Spectroscopic Analysis of Planetary Host Stars

    Science.gov (United States)

    Rittipruk, P.; Yushchenko, A.; Kang, Y. W.

    2014-08-01

    We observed the high resolution spectra of extra-solar planet host stars. The spectroscopic data of host stars were observed using the CHIRON echelle spectrometer and R-C Spectrograph for magnetic activity on the SMART-1.5 meter telescope at CTIO, Chile. The analysis of spectroscopic data was performed using URAN and SYNTHE programs. These spectra allow us to determine the effective temperatures, surface gravities, microturbulent velocities and, finally, the chemical composition of the hosts was obtained by spectrum synthesis. One of the targets, namely HD 47536, the host of two planets, appeared to be a halo star with overabundances of neutron capture elements. The effective temperature and the surface gravity of this star are 4400 K and log=1.5 respectively, the iron is underabundant by 0.6 dex. The heavy elements (up to thorium, Z=90) show the overabundances with respect to iron. The signs of accretion of interstellar gas are found in the atmosphere of this star.

  8. The greenhouse effect of planetary atmospheres

    International Nuclear Information System (INIS)

    Kondratyev, K.Ya.; Moskalenko, N.I.

    1980-01-01

    The greenhouse effect of the atmosphere is the main factor of possible climate changes of anthropogenic origin. The growing pollution of the atmosphere leads to an increase of the concentration of various gaseous components. Of great importance is also the consideration of the aerosols. All the gaseous components, as well as aerosols, have the absorption bands in the IR spectral range. The traditional attention to the problem of the CO 2 contribution to the greenhouse effect has somewhat overshadowed the significance of the different components. The data characterizing the significance of the different components of the greenhouse effect are considered. The results of studying the absorption spectra of methane, nitrous oxides, sulphuric gas, ammonia, nitric-acid vapours and other components are discussed. The assessments of their contribution to the greenhouse effect are given. The important role of the small-size fraction of the atmospheric aerosols as a factor of the greenhouse effect is discussed. Both the analysis of the causes of the Earth's climate variability and the relevant investigation of the atmospheric greenhouse effect determine the expediency of analysing the conditions of the greenhouse effect formation on other planets. Laboratory studies of the IR absorption spectra of synthetic CO 2 atmospheres were carried out. Some results from these studies are discussed. (author)

  9. A bibliography of planetary geology principal investigators and their associates, 1976--1978

    International Nuclear Information System (INIS)

    1978-05-01

    This bibliography cites publications submitted by 484 principal investigators and their associates who were supported through NASA's Office of Space Sciences Planetary Geology Program. Subject classifications include solar system formation, comets, and asteroids; planetary satellites, planetary interiors, geological and geochemical constraints on planetary evolution; impact crater studies, volcanism, eolian studies, fluvian studies, Mars geological mapping; Mercury geological mapping; planetary cartography; and instrument development and techniques. An author/editor index is provided

  10. HESS Opinions: A planetary boundary on freshwater use is misleading

    Science.gov (United States)

    Heistermann, Maik

    2017-07-01

    In 2009, a group of prominent Earth scientists introduced the planetary boundaries (PB) framework: they suggested nine global control variables, and defined corresponding thresholds which, if crossed, could generate unacceptable environmental change. The concept builds on systems theory, and views Earth as a complex adaptive system in which anthropogenic disturbances may trigger non-linear, abrupt, and irreversible changes at the global scale, and push the Earth system outside the stable environmental state of the Holocene. While the idea has been remarkably successful in both science and policy circles, it has also raised fundamental concerns, as the majority of suggested processes and their corresponding planetary boundaries do not operate at the global scale, and thus apparently lack the potential to trigger abrupt planetary changes. This paper picks up the debate with specific regard to the planetary boundary on global freshwater use. While the bio-physical impacts of excessive water consumption are typically confined to the river basin scale, the PB proponents argue that water-induced environmental disasters could build up to planetary-scale feedbacks and system failures. So far, however, no evidence has been presented to corroborate that hypothesis. Furthermore, no coherent approach has been presented to what extent a planetary threshold value could reflect the risk of regional environmental disaster. To be sure, the PB framework was revised in 2015, extending the planetary freshwater boundary with a set of basin-level boundaries inferred from environmental water flow assumptions. Yet, no new evidence was presented, either with respect to the ability of those basin-level boundaries to reflect the risk of regional regime shifts or with respect to a potential mechanism linking river basins to the planetary scale. So while the idea of a planetary boundary on freshwater use appears intriguing, the line of arguments presented so far remains speculative and

  11. HESS Opinions: A planetary boundary on freshwater use is misleading

    Directory of Open Access Journals (Sweden)

    M. Heistermann

    2017-07-01

    Full Text Available In 2009, a group of prominent Earth scientists introduced the planetary boundaries (PB framework: they suggested nine global control variables, and defined corresponding thresholds which, if crossed, could generate unacceptable environmental change. The concept builds on systems theory, and views Earth as a complex adaptive system in which anthropogenic disturbances may trigger non-linear, abrupt, and irreversible changes at the global scale, and push the Earth system outside the stable environmental state of the Holocene. While the idea has been remarkably successful in both science and policy circles, it has also raised fundamental concerns, as the majority of suggested processes and their corresponding planetary boundaries do not operate at the global scale, and thus apparently lack the potential to trigger abrupt planetary changes.This paper picks up the debate with specific regard to the planetary boundary on global freshwater use. While the bio-physical impacts of excessive water consumption are typically confined to the river basin scale, the PB proponents argue that water-induced environmental disasters could build up to planetary-scale feedbacks and system failures. So far, however, no evidence has been presented to corroborate that hypothesis. Furthermore, no coherent approach has been presented to what extent a planetary threshold value could reflect the risk of regional environmental disaster. To be sure, the PB framework was revised in 2015, extending the planetary freshwater boundary with a set of basin-level boundaries inferred from environmental water flow assumptions. Yet, no new evidence was presented, either with respect to the ability of those basin-level boundaries to reflect the risk of regional regime shifts or with respect to a potential mechanism linking river basins to the planetary scale.So while the idea of a planetary boundary on freshwater use appears intriguing, the line of arguments presented so far remains

  12. Precession effects on a liquid planetary core

    Science.gov (United States)

    Liu, Min; Li, Li-Gang

    2018-02-01

    Motivated by the desire to understand the rich dynamics of precessionally driven flow in a liquid planetary core, we investigate, through numerical simulations, the precessing fluid motion in a rotating cylindrical annulus, which simultaneously possesses slow precession. The same problemhas been studied extensively in cylinders, where the precessing flow is characterized by three key parameters: the Ekman number E, the Poincaré number Po and the radius-height aspect ratio Γ. While in an annulus, there is another parameter, the inner-radius-height aspect ratio ϒ, which also plays an important role in controlling the structure and evolution of the flow. By decomposing the nonlinear solution into a set of inertial modes, we demonstrate the properties of both weakly and moderately precessing flows. It is found that, when the precessional force is weak, the flow is stable with a constant amplitude of kinetic energy. As the precessional force increases, our simulation suggests that the nonlinear interaction between the boundary effects and the inertial modes can trigger more turbulence, introducing a transitional regime of rich dynamics to disordered flow. The inertial mode u 111, followed by u 113 or u 112, always dominates the precessing flow when 0.001 ≤ Po ≤ 0.05, ranging from weak to moderate precession. Moreover, the precessing flow in an annulus shows more stability than in a cylinder which is likely to be caused by the effect of the inner boundary that restricts the growth of resonant and non-resonant inertial modes. Furthermore, the mechanism of triadic resonance is not found in the transitional regime from a laminar to disordered flow.

  13. Distinguishing between symbiotic stars and planetary nebulae

    Science.gov (United States)

    Iłkiewicz, K.; Mikołajewska, J.

    2017-10-01

    Context. The number of known symbiotic stars (SySt) is still significantly lower than their predicted population. One of the main problems in finding the total population of SySt is the fact that their spectrum can be confused with other objects, such as planetary nebulae (PNe) or dense H II regions. This problem is reinforced by the fact that in a significant fraction of established SySt the emission lines used to distinguish them from other objects are not present. Aims: We aim at finding new diagnostic diagrams that could help separate SySt from PNe. Additionally, we examine a known sample of extragalactic PNe for candidate SySt. Methods: We employed emission line fluxes of known SySt and PNe from the literature. Results: We found that among the forbidden lines in the optical region of spectrum, only the [O III] and [N II] lines can be used as a tool for distinguishing between SySt and PNe, which is consistent with the fact that they have the highest critical densities. The most useful diagnostic that we propose is based on He I lines, which are more common and stronger in SySt than forbidden lines. All these useful diagnostic diagrams are electron density indicators that better distinguish PNe and ionized symbiotic nebulae. Moreover, we found six new candidate SySt in the Large Magellanic Cloud and one in M 81. If confirmed, the candidate in M 81 would be the farthest known SySt thus far.

  14. Toward predictive scenarios of planetary migration

    International Nuclear Information System (INIS)

    Baruteau, Clement

    2008-01-01

    The recent detection of extra-solar planets has provided an exciting opportunity to test our theories of planet formation and evolution. An impressive result is the significant proportion of giant planets located much closer to their star than Mercury is from our own Sun. These planets should have formed further out in the protoplanetary disc, thus one needs to explain how they could move closer to their host star. Remarkably enough, such an explanation was proposed well before the discovery of the first exo-planet. It considered the interaction between a planet and the protoplanetary disc, which leads to a decrease of the planet's semi-major axis. This is known as planetary migration. Many studies have shown that the migration timescale of low-mass planets is much shorter than the lifetime of the disc. All planets should therefore have migrated to the vicinity of their host star. This is at least in contradiction with the locations of the planets in our Solar System. In order to elaborate predictive scenarios of planet formation and evolution, it is of primary interest to refine our understanding of disc-planet interactions. The inclusion of the disc self-gravity is an illustration of this. With analytical and numerical arguments, I show that discarding the self-gravity leads to a significant overestimate of the differential Lindblad torque for migrating low-mass planets. Another aspect explored in this thesis is the impact of the gas thermodynamics on migration. I show that the thermodynamic evolution of the disc induces an additional contribution to the corotation torque, which may dramatically slow down or even reverse the migration of low-mass planets. (author) [fr

  15. Asymmetric Planetary Nebulae VI: the conference summary

    Science.gov (United States)

    De Marco, O.

    2014-04-01

    The Asymmetric Planetary Nebulae conference series, now in its sixth edition, aims to resolve the shaping mechanism of PN. Eighty percent of PN have non spherical shapes and during this conference the last nails in the coffin of single stars models for non spherical PN have been put. Binary theories abound but observational tests are lagging. The highlight of APN6 has been the arrival of ALMA which allowed us to measure magnetic fields on AGB stars systematically. AGB star halos, with their spiral patterns are now connected to PPN and PN halos. New models give us hope that binary parameters may be decoded from these images. In the post-AGB and pre-PN evolutionary phase the naked post-AGB stars present us with an increasingly curious puzzle as complexity is added to the phenomenologies of objects in transition between the AGB and the central star regimes. Binary central stars continue to be detected, including the first detection of longer period binaries, however a binary fraction is still at large. Hydro models of binary interactions still fail to give us results, if we make an exception for the wider types of binary interactions. More promise is shown by analytical considerations and models driven by simpler, 1D simulations such as those carried out with the code MESA. Large community efforts have given us more homogeneous datasets which will yield results for years to come. Examples are the ChanPlaN and HerPlaNe collaborations that have been working with the Chandra and Herschel space telescopes, respectively. Finally, the new kid in town is the intermediate-luminosity optical transient, a new class of events that may have contributed to forming several peculiar PN and pre-PN.

  16. Morpho-kinematic modeling of planetary nebulae

    Science.gov (United States)

    Chan, Tsz-Pan (Henry)

    2009-11-01

    The Planetary Nebulae (PNe) are the transition phase between asymptotic giant branch (AGB) star and white dwarfs for stars with masses between 1 and 8 M⊙. They were originally thought to be well-studied and can be explained with simple models. With the advance of imaging technology especially on Space Telescope (HST), the shapes of PNe have been found to be much more complex than we assumed to be. We aimed to investigate on the basic but mysterious intrinsic three-dimensional structures using the newly developed modeling software. Astronomers usually use the morphological classification on group and classify different properties of PNe. Over the past century many attempts have been made for this classification to seek for explaining and understanding the threedimensional structure that is responsible for the observed images. There have been two beliefs in explaining the variety of shapes of PNe and among them the most amazing one is that the morphologies can be accounted by different orientations of a single structure (Khromov & Kohoutek, 1968). Motivated by the study of Ring Nebula on its intrinsic structure, we investigated the possibility that different types of morphology in PNe can be explained by a single model. We used the newly developed modeling code SHAPE (Steffen et al., 2006), which cooperates the use of spatial information as well as its kinematics, and aimed to quantitatively investigate the basic structure inside PNe. We investigated two classical nebulae: NGC 2346 and NGC 2440. We proposed a simple but adequate model for these nebulae. Stimulated optical images and the p-v arrays were derived by the modeling code SHAPE to make comparison with the observed data to seek for the correctness of the model. Hubble velocity field and inverse square law density distribution were assumed throughout the modeling process. This model provides insights in seeking further adequate intrinsic structure of PNe.

  17. Ultraviolet imaging of planetary nebulae with GALEX

    Science.gov (United States)

    Bianchi, Luciana; Thilker, David

    2018-05-01

    Over four hundred Galactic Planetary Nebulae (PNe) have been imaged by GALEX in two ultraviolet (UV) bands, far-UV (FUV, 1344-1786 Å, λ _{eff}= 1528 Å) and near-NUV (NUV, 1771-2831 Å, λ _{eff} = 2271 Å). We present examples of extended PNe, for which UV spectroscopy is also available, to illustrate the variety in UV morphology and color, which reflects ionization conditions. The depth of the GALEX imaging varies from flux ≈ 0.4/5× 10 ^{-18} ergs cm^{-2} s^{-1} Å^{-1} \\square ^'' -1} (FUV/NUV) for exposures of the order of ˜ 100 seconds, typical of the survey with the largest area coverage, to ˜ 0.3/8.3× 10^{-19} ergs cm^{-2} s^{-1} Å^{-1} \\square ^'' -1} (FUV/NUV) for ˜ 1500 sec exposures, typical of the second largest survey (see Bianchi in Astrophys. Space Sci. 320:11, 2009; Bianchi et al. in Adv. Space Res. 53:900, 2014). GALEX broad-band FUV and NUV fluxes include nebular emission lines and in some cases nebular continuum emission. The sensitivity of the GALEX instrument and the low sky background, especially in FUV, enable detection and mapping of very faint ionization regions and fronts, including outermost wisps and bow shocks. The FUV-NUV color of the central star provides a good indication of its T_{eff}, because the GALEX FUV-NUV color is almost reddening-free for Milky Way type dust (Bianchi et al. in Astrophys. J. Suppl. Ser. 230:24, 2017; Bianchi in Astrophys. Space Sci. 335:51, 2011, Bianchi in Astrophys. Space Sci. 354:103, 2014) and it is more sensitive to hot temperatures than optical colors.

  18. Dry Powder Coating using Planetary Centrifugal Mixer.

    Science.gov (United States)

    Miyazaki, Yasunori; Miyawaki, Kaoru; Uchino, Tomonobu; Kagawa, Yoshiyuki

    2015-01-01

    Extemporaneous compounding is an important part of pharmacy practice, and should be standardized and sophisticated to ensure the quality of the compounded preparations. Recently, we applied a planetary centrifugal mixer (PCM) to powder blending, which has attracted interest for its small scale and lack of contamination. In this study, we aimed to reveal the feasibility of dry powder coating through ordered mixing of fine particles using PCM. Cohesive lactose powders (Pharmatose450M) were dry coated with magnesium stearate (MgSt) using from 0.1 to 5%(w/w) content. The operational variables tested were operation time (1-30 min), operation speed (400-1000 rpm), vessel size (24-100 mL), and charging rate in the vessel (20-40%). The processed powders were evaluated for their surface morphology, flowability, and wettability. Furthermore, fine ibuprofen particles were coated with various lubricants, and then the dissolution profiles were examined. The crystallinity of ibuprofen was assessed using FT-IR and PXRD. Lactose powders were successfully coated with MgSt using PCM. When the level of MgSt was over 1%, the surface of the lactose powders was thoroughly covered. Angles of repose were 51° and 41° for unprocessed and processed powders with 1% MgSt, respectively. The contact angle of the water drop on the 1% MgSt sample leached to be 132°, changing to a hydrophobic surface. Investigations under various operational conditions revealed that higher improvement was observed upon higher speed and longer time, and a smaller charging rate in the vessel. Vessel size had no impact. Moreover, improved dissolution of ibuprofen coated with both hydrophilic and hydrophobic lubricants was observed owing to good dispersing behavior. Besides, no alteration of crystallinity was detected. PCM is an effective tool for dry powder coating with low impact stress. The presented method will contribute a great deal to making crushed tablets a functional powder.

  19. Integrating Information Networks for Collective Planetary Stewardship

    Science.gov (United States)

    Tiwari, A.

    2016-12-01

    Responsible behaviour resulting from climate literacy in global environmental movement is limited to policy and planning institutions in the Global South, while remaining absent for ends-user. Thus, planetary stewardship exists only at earth system boundaries where pressures sink to the local scale while ethics remains afloat. Existing citizen participation is restricted within policy spheres, appearing synonymous to enforcements in social psychology. Much, accounted reason is that existing information mechanisms operate mostly through linear exchanges between institutions and users, therefore reinforcing only hierarchical relationships. This study discloses such relationships that contribute to broad networking gaps through information demand assessment of stakeholders in a dozen development projects based in South Asia. Two parameters widely used for this purpose are: a. Feedback: Ends-user feedback to improve consumption literacy of climate sensitive resources (through consumption displays, billing, advisory services ecolabelling, sensors) and, b. Institutional Policy: Rewarding punishing to enforce desired behaviour (subsidies, taxation). Research answered: 1. Who gets the information (Equity in Information Distribution)? As existing information publishing mechanisms are designed by and for analysts, 2. How information translates to climate action Transparency of Execution)? Findings suggested that climate goals manifested in economic policy, than environmental policy, have potential clear short-term benefits and costs, and coincide with people's economic goals Also grassroots roles for responsible behaviour are empowered with presence of end user information. Barier free climate communication process and decision making is ensured among multiplicity of stakeholders with often conflicting perspectives. Research finds significance where collaboration among information networks can better translate regional policies into local action for climate adaptation and

  20. Central stars of planetary nebulae. II. New OB-type and emission-line stars

    Science.gov (United States)

    Weidmann, W. A.; Gamen, R.

    2011-07-01

    Context. There are more than 3000 confirmed and probably known Galactic planetary nebulae (PNe), but central star spectroscopic information is available for only 13% of them. Aims: We have undertaken a spectroscopic survey of the central stars in PNe to identify their spectral types. Methods: We performed spectroscopic observations at low resolution with the 2-m telescope at CASLEO, Argentina. Results: We present the spectra of 46 central stars of PNe, most of them are OB-type and emission-line stars. Based on data collected at the Complejo Astronómico El Leoncito (CASLEO), which is operated under agreement between the Consejo Nacional de Investigaciones Científicas y Técnicas de la República Argentina y Universidades Nacionales de La Plata, Córdoba y San Juan, Argentina.The reduced spectra (FITS files) are available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/531/A172

  1. Study of the shape of β spectra

    International Nuclear Information System (INIS)

    Bisch, Charlene

    2014-01-01

    The goal of this PhD work is to build an experimental device dedicated to measuring beta spectra with a precision relevant to modern metrology requirements. The device, which is based on a silicon semi-conductor detector, must take into account certain physical phenomena and detector characteristics which could lead to deformation of the measured spectra. These must be understood and minimized. Monte-Carlo simulations have allowed the geometry and construction materials to be optimized. The quality of the radioactive sources is paramount in obtaining spectra of high-quality. Nonetheless, the measured spectra must be corrected for any remaining distortion. A response function must therefore be determined for each measurement geometry. This can be achieved via Monte-Carlo simulations. The first results show that deconvolution of the measured spectra with the response function makes possible the accurate determination of the true form of the beta spectra. (author) [fr

  2. Calculation of reactor antineutrino spectra in TEXONO

    CERN Document Server

    Chen Dong Liang; Mao Ze Pu; Wong, T H

    2002-01-01

    In the low energy reactor antineutrino physics experiments, either for the researches of antineutrino oscillation and antineutrino reactions, or for the measurement of abnormal magnetic moment of antineutrino, the flux and the spectra of reactor antineutrino must be described accurately. The method of calculation of reactor antineutrino spectra was discussed in detail. Furthermore, based on the actual circumstances of NP2 reactors and the arrangement of detectors, the flux and the spectra of reactor antineutrino in TEXONO were worked out

  3. Structure of high-resolution NMR spectra

    CERN Document Server

    Corio, PL

    2012-01-01

    Structure of High-Resolution NMR Spectra provides the principles, theories, and mathematical and physical concepts of high-resolution nuclear magnetic resonance spectra.The book presents the elementary theory of magnetic resonance; the quantum mechanical theory of angular momentum; the general theory of steady state spectra; and multiple quantum transitions, double resonance and spin echo experiments.Physicists, chemists, and researchers will find the book a valuable reference text.

  4. Influence of Planetary Protection Guidelines on Waste Management Operations

    Science.gov (United States)

    Hogan, John A.; Fisher, John W.; Levri, Julie A.; Wignarajah, Kanapathipi; Race, Margaret S.; Stabekis, Perry D.; Rummel, John D.

    2005-01-01

    Newly outlined missions in the Space Exploration Initiative include extended human habitation on Mars. During these missions, large amounts of waste materials will be generated in solid, liquid and gaseous form. Returning these wastes to Earth will be extremely costly, and will therefore likely remain on Mars. Untreated, these wastes are a reservoir of live/dead organisms and molecules considered to be "biomarkers" i.e., indicators of life). If released to the planetary surface, these materials can potentially confound exobiology experiments and disrupt Martian ecology indefinitely (if existent). Waste management systems must therefore be specifically designed to control release of problematic materials both during the active phase of the mission, and for any specified post-mission duration. To effectively develop waste management requirements for Mars missions, planetary protection guidelines must first be established. While previous policies for Apollo lunar missions exist, it is anticipated that the increased probability of finding evidence of life on Mars, as well as the lengthy mission durations will initially lead to more conservative planetary protection measures. To facilitate the development of overall requirements for both waste management and planetary protection for future missions, a workshop was conducted to identify how these two areas interface, and to establish a preliminary set of planetary protection guidelines that address waste management operations. This paper provides background regarding past and current planetary protection and waste management issues, and their interactions. A summary of the recommended planetary protection guidelines, anticipated ramifications and research needs for waste management system design for both forward (Mars) and backward (Earth) contamination is also provided.

  5. Planetary Data Systems (PDS) Imaging Node Atlas II

    Science.gov (United States)

    Stanboli, Alice; McAuley, James M.

    2013-01-01

    The Planetary Image Atlas (PIA) is a Rich Internet Application (RIA) that serves planetary imaging data to the science community and the general public. PIA also utilizes the USGS Unified Planetary Coordinate system (UPC) and the on-Mars map server. The Atlas was designed to provide the ability to search and filter through greater than 8 million planetary image files. This software is a three-tier Web application that contains a search engine backend (MySQL, JAVA), Web service interface (SOAP) between server and client, and a GWT Google Maps API client front end. This application allows for the search, retrieval, and download of planetary images and associated meta-data from the following missions: 2001 Mars Odyssey, Cassini, Galileo, LCROSS, Lunar Reconnaissance Orbiter, Mars Exploration Rover, Mars Express, Magellan, Mars Global Surveyor, Mars Pathfinder, Mars Reconnaissance Orbiter, MESSENGER, Phoe nix, Viking Lander, Viking Orbiter, and Voyager. The Atlas utilizes the UPC to translate mission-specific coordinate systems into a unified coordinate system, allowing the end user to query across missions of similar targets. If desired, the end user can also use a mission-specific view of the Atlas. The mission-specific views rely on the same code base. This application is a major improvement over the initial version of the Planetary Image Atlas. It is a multi-mission search engine. This tool includes both basic and advanced search capabilities, providing a product search tool to interrogate the collection of planetary images. This tool lets the end user query information about each image, and ignores the data that the user has no interest in. Users can reduce the number of images to look at by defining an area of interest with latitude and longitude ranges.

  6. Infrared quantitative spectroscopy and planetary atmospheres

    Science.gov (United States)

    Flaud, J.-M.

    2009-04-01

    Optical measurements of atmospheric minor constituents are carried out using spectrometers working in the UV-visible, infrared and microwave spectral ranges. In all cases the quality of the analysis and of the interpretation of the atmospheric spectra requires the best possible knowledge of the molecular parameters of the species of interest. To illustrate this point we will concentrate on recent laboratory studies of nitric acid, chlorine nitrate and formaldehyde. Nitric acid is one of the important minor constituent of the terrestrial atmosphere. Using new and accurate experimental results concerning the spectroscopic properties of the H14NO3 and H15NO3 molecules, as well as improved theoretical methods (Perrin et al., 2004), it has been possible to generate an improved set of line parameters for these molecules in the 11.2 μm spectral region. These line parameters were used to detect for the first time the H15NO3 molecule in the atmosphere analyzing atmospheric spectra recorded by the MIPAS experiment. The retrievals of chlorine nitrate profiles are usually performed using absorption cross sections (Birk and Wagner, 2003). Following a high resolution analysis of the ν3 and ν4bands of this species in the 12.8 μm region wepropose, as a possibility, to use line by line calculation simulating its ν4Q-branch for the atmospheric temperature and pressure ranges. For the measurement of atmospheric formaldehyde concentrations, mid-infrared and ultraviolet absorptions are both used by ground, air or satellite instruments. It is then of the utmost importance to have consistent spectral parameters in these various spectral domains. Consequently the aim of the study performed at LISA (Gratien et al., 2007) was to intercalibrate formaldehyde spectra in the infrared and ultraviolet regions acquiring simultaneously UV and IR spectra using a common optical cell. The results of the work will be presented. Also high resolution infrared data derived from Perrin et al., 2003

  7. Neutron and photon spectra in LINACs

    International Nuclear Information System (INIS)

    Vega-Carrillo, H.R.; Martínez-Ovalle, S.A.; Lallena, A.M.; Mercado, G.A.; Benites-Rengifo, J.L.

    2012-01-01

    A Monte Carlo calculation, using the MCNPX code, was carried out in order to estimate the photon and neutron spectra in two locations of two linacs operating at 15 and 18 MV. Detailed models of both linac heads were used in the calculations. Spectra were estimated below the flattening filter and at the isocenter. Neutron spectra show two components due to evaporation and knock-on neutrons. Lethargy spectra under the filter were compared to the spectra calculated from the function quoted by Tosi et al. that describes reasonably well neutron spectra beyond 1 MeV, though tends to underestimate the energy region between 10 –6 and 1 MeV. Neutron and the Bremsstrahlung spectra show the same features regardless of the linac voltage. - Highlights: ► With MCNPX code realistic models of two LINACs were built. ► Photon and neutron spectra below the flattening filter and at the isocenter were calculated. ► Neutron spectrum at the flattening filter was compared against the Tosi et al. source-term model. ► Tosi et al. model underestimates the neutron contribution below 1 MeV. ► Photon spectra look alike to those published in literature.

  8. Infrared spectra of thyroid tumor tissues

    Science.gov (United States)

    Tolstorozhev, G. B.; Skornyakov, I. V.; Butra, V. A.

    2010-07-01

    We used infrared spectroscopy methods to study thyroid tumor tissues removed during surgery. The IR spectra of the surgical material are compared with data from histological examination. We show that in malignant neoplasms, the spectra of proteins in the region of C=O vibrations are different from the spectra of these substances in benign tumors and in tissues outside the pathological focus at a distance >1 cm from the margin of the tumor. The differences in the spectra are due to changes in the supermolecular structure of the proteins, resulting from rearrangement of the system of hydrogen bonds. We identify the spectral signs of malignant pathologies.

  9. Optical absorption spectra of Ag-11 isomers

    DEFF Research Database (Denmark)

    Martinez, Jose Ignacio; Fernandez, E. M.

    2009-01-01

    The optical absorption spectra of the three most; stable structural isomers of the Ag-11 cluster were calculated using the time-dependent, density functional theory within the Casida formalism. The slightly different, spectra, of the isomers may permit the identification of the ground-stale confi......The optical absorption spectra of the three most; stable structural isomers of the Ag-11 cluster were calculated using the time-dependent, density functional theory within the Casida formalism. The slightly different, spectra, of the isomers may permit the identification of the ground...

  10. Reflectance spectra of subarctic lichens

    International Nuclear Information System (INIS)

    Petzold, D.E.; Goward, S.N.

    1988-01-01

    Lichens constitute a major portion of the ground cover of high latitude environments, but little has been reported concerning their in situ solar spectral reflectance properties. Knowledge of these properties is important for the interpretation of remotely sensed observations from high latitude regions, as well as in studies of high latitude ecology and energy balance climatology. The spectral reflectance of common boreal vascular plants is similar to that of vascular plants of the mid latitudes. The dominant lichens, in contrast, display variable reflectance patterns in visible wavelengths. The relative reflectance peak at 0.55 μm, common to green vegetation, is absent or indistinct in spectra of pervasive boreal forest and tundra lichens, despite the presence of chlorophyll in the inner algal cells. Lichens of the dominant genus, Cladina, display strong absorption of ultraviolet energy and short-wavelength blue light relative to their absorption in other visible wavelengths. Since the Cladinae dominate both the surface vegetation in open woodlands of the boreal forest and the low arctic tundra, their unusual spectral reflectance patterns will enable accurate monitoring of the boreal forest-tundra ecotone and detection of its vigor and movement in the future. (author)

  11. Reflectance spectra of subarctic lichens

    Science.gov (United States)

    Petzold, Donald E.; Goward, Samuel N.

    1988-01-01

    Lichens constitute a major portion of the ground cover of high latitude environments, but little has been reported concerning their in situ solar spectral reflectance properties. Knowledge of these properties is important for the interpretation of remotely sensed observations from high latitude regions, as well as in studies of high latitude ecology and energy balance climatology. The spectral reflectance of common boreal vascular plants is similar to that of vascular plants of the midlatitudes. The dominant lichens, in contrast, display variable reflectance patterns in visible wavelengths. The relative reflectance peak at 0.55 microns, common to green vegetation, is absent or indistinct in spectra of pervasive boreal forest and tundra lichens, despite the presence of chlorophyll in the inner algal cells. Lichens of the dominant genus, Cladina, display strong absorption of ultraviolet energy and short-wavelength blue light relative to their absorption in other visible wavelengths. Since the Cladinae dominate both the surface vegetation in open woodlands of the boreal forest and the low arctic tundra, their unusual spectral reflectance patterns will enable accurate monitoring of the boreal forest-tundra ecotone and detection of its vigor and movement in the future.

  12. Methodology for analyzing weak spectra

    International Nuclear Information System (INIS)

    Yankovich, T.L.; Swainson, I.P.

    2000-02-01

    There is considerable interest in quantifying radionuclide transfer between environmental compartments. However, in many cases, it can be a challenge to detect concentrations of gamma-emitting radionuclides due to their low levels in environmental samples. As a result, it is valuable to develop analytical protocols to ensure consistent analysis of the areas under weak peaks. The current study has focused on testing how reproducibly peak areas and baselines can be determined using two analytical approaches. The first approach, which can be carried out using Maestro software, involves extracting net counts under a curve without fitting a functional form to the peak, whereas the second approach, which is used by most other peak fitting programs, determines net counts from spectra by fitting a Gaussian form to the data. It was found that the second approach produces more consistent peak area and baseline measurements, with the ability to de-convolute multiple, overlapping peaks. In addition, programs, such as Peak Fit, which can be used to fit a form to spectral data, often provide goodness of fit analyses, since the Gaussian form can be described using a characteristic equation against which peak data can be tested for their statistical significance. (author)

  13. Abundances of planetary nebulae NGC 7662 and NGC 6741

    NARCIS (Netherlands)

    Pottasch, [No Value; Beintema, DA; Salas, JB; Feibelman, WA

    2001-01-01

    The ISO and IUE spectra of the elliptical nebulae NGC7662 and NGC6741 are presented. These spectra are combined with the spectra in the visual wavelength region to obtain a complete, extinction corrected, spectrum. The chemical composition of the nebulae is then calculated and compared to previous

  14. Abundances of the planetary nebula Hu 1-2

    NARCIS (Netherlands)

    Pottasch, [No Value; Hyung, S; Aller, LH; Beintema, DA; Bernard-Salas, J; Feibelman, WA; Klockner, HR

    The ISO and IUE spectra of the "elliptical" nebula Hu 1-2 are presented. These spectra are combined with new, high resolution spectra in the visual wavelength region to obtain a complete, extinction corrected, spectrum. The chemical composition of the nebula is then calculated and compared to

  15. Planetary radar data inversion techniques improvement

    Science.gov (United States)

    Picardi, G.; Masdea, A.; Mastrogiuseppe, M.; Restano, M.; Seu, R.

    2012-04-01

    The planetary radar (e.g. MARSIS) data inversion is based on the selection of groups of stationary frames, within the area under investigation, that shall be statistically analyzed after suitable correction. The selection step includes the recovery of bad/poor data and the estimation of the geometrical surface and subsurface features; these feature shall be utilized in order to obtain data that are only dependent by the material nature of the inclusion, within the layer, and of the interface. This paper is addressed to the techniques used for the frames selection, recovery and their geometric estimation content. As first step, frames have been selected in Mars areas where the surface and subsurface have a physical optics behavior (i.e. quite flat); the surface flatness has been estimated according to a simulator based on MOLA (Mars Orbiter Laser Altimeter) data while the subsurface has been estimated taking into account the Doppler filters content (i.e. filter 0, +1, -1). Being the surface and subsurface quite flat only small geometric contribution have been estimated and used for correction of the received echoes. To perform this task surface and subsurface models have been developed, under the Kirchhoff approximation hypothesis, to be compared with the experimental data. A figure showing the different material nature of different areas of the Mars South Pole has been drawn. The discovery of areas with an high dielectric constant led geologists to analyze those areas with other instrument to confirm the results obtained by MARSIS. This paper outlines also the way out for future works in order to analyze more complex surface and subsurface scenarios where conditions for geometric optics or fractal can be present. In this case, it will be mandatory to develop a clutter cancellation technique to avoid the presence of false subsurface echoes generated by surface and subsurface features not immediately below the nadir direction of observation. It will be also necessary

  16. Expansion patterns and parallaxes for planetary nebulae

    Science.gov (United States)

    Schönberner, D.; Balick, B.; Jacob, R.

    2018-02-01

    Aims: We aim to determine individual distances to a small number of rather round, quite regularly shaped planetary nebulae by combining their angular expansion in the plane of the sky with a spectroscopically measured expansion along the line of sight. Methods: We combined up to three epochs of Hubble Space Telescope imaging data and determined the angular proper motions of rim and shell edges and of other features. These results are combined with measured expansion speeds to determine individual distances by assuming that line of sight and sky-plane expansions are equal. We employed 1D radiation-hydrodynamics simulations of nebular evolution to correct for the difference between the spectroscopically measured expansion velocities of rim and shell and of their respective shock fronts. Results: Rim and shell are two independently expanding entities, driven by different physical mechanisms, although their model-based expansion timescales are quite similar. We derive good individual distances for 15 objects, and the main results are as follows: (i) distances derived from rim and shell agree well; (ii) comparison with the statistical distances in the literature gives reasonable agreement; (iii) our distances disagree with those derived by spectroscopic methods; (iv) central-star "plateau" luminosities range from about 2000 L⊙ to well below 10 000 L⊙, with a mean value at about 5000 L⊙, in excellent agreement with other samples of known distance (Galactic bulge, Magellanic Clouds, and K648 in the globular cluster M 15); (v) the central-star mass range is rather restricted: from about 0.53 to about 0.56 M⊙, with a mean value of 0.55 M⊙. Conclusions: The expansion measurements of nebular rim and shell edges confirm the predictions of radiation-hydrodynamics simulations and offer a reliable method for the evaluation of distances to suited objects. Results of this paper are based on observations made with the NASA/ESA Hubble Space Telescope in Cycle 16 (GO11122

  17. Planetary Protection Considerations in EVA System Design

    Science.gov (United States)

    Eppler, Dean B.; Kosmo, Joseph J.

    2011-01-01

    very little expression of these anomalies. hardware from the human-occupied area may limit (although not likely eliminate) external materials in the human habitat. Definition of design-to requirements is critical to understanding technical feasibility and costs. The definition of Planetary Protection needs in relation to EVA mission and system element development cost impacts should be considered and interpreted in terms of Plausible Protection criteria. Since EVA operations will have the most direct physical interaction with the Martian surface, PP needs should be considered in the terms of mitigating hardware and operations impacts and costs.

  18. On planetary nebulae as sources of carbon dust: Infrared emission from planetary nebulae of the galactic halo

    International Nuclear Information System (INIS)

    Dinerstein, H.L.; Lester, D.F.

    1990-01-01

    Researchers examine here the characteristics of the infrared emission from the four planetary nebulae which are believed on the basis of their low overall metallicities to belong to the halo population. These nebulae are of particular interest because they are the most metal-poor ionized nebulae known in our Galaxy, and offer the opportunity to probe possible dependences of the dust properties on nebular composition. Researchers present fluxes extracted from co-addition of the IRAS data, as well as ground-based near infrared measurements. Each of the four halo objects, including the planetary nebula in the globular cluster M15, is detected in at least one infrared band. Researchers compare the estimated infrared excesses of these nebulae (IRE, the ratio of measured infrared power to the power available in the form of resonantly-trapped Lyman alpha photons) to those of disk planetary nebulae with similar densities but more normal abundances. Three of the halo planetaries have IRE values similar to those of the disk nebulae, despite the fact that their Fe- and Si-peak gas phase abundances are factors of 10 to 100 lower. However, these halo nebulae have normal or elevated C/H ratios, due to nuclear processing and mixing in their red giant progenitors. Unlike the other halo planetaries, DDDM1 is deficient in carbon as well as in the other light metals. This nebula has a substantially lower IRE than the other halo planetaries, and may be truly dust efficient. Researchers suggest that the deficiency is due to a lack of the raw material for producing carbon-based grains, and that the main bulk constituent of the dust in these planetary nebulae is carbon

  19. Interdisciplinary Research Produces Results in the Understanding of Planetary Dunes

    Science.gov (United States)

    Titus, Timothy N.; Hayward, Rosalyn Kay; Bourke, Mary C.

    2010-08-01

    Second International Planetary Dunes Workshop: Planetary Analogs—Integrating Models, Remote Sensing, and Field Data; Alamosa, Colorado, 18-21 May 2010; Dunes and other eolian bed forms are prominent on several planetary bodies in our solar system. Despite 4 decades of study, many questions remain regarding the composition, age, and origins of these features, as well as the climatic conditions under which they formed. Recently acquired data from orbiters and rovers, together with terrestrial analogs and numerical models, are providing new insights into Martian sand dunes, as well as eolian bed forms on other terrestrial planetary bodies (e.g., Titan). As a means of bringing together terrestrial and planetary researchers from diverse backgrounds with the goal of fostering collaborative interdisciplinary research, the U.S. Geological Survey (USGS), the Carl Sagan Center for the Study of Life in the Universe, the Desert Research Institute, and the U.S. National Park Service held a workshop in Colorado. The small group setting facilitated intensive discussion of problems and issues associated with eolian processes on Earth, Mars, and Titan.

  20. Planetary gearbox fault diagnosis using an adaptive stochastic resonance method

    Science.gov (United States)

    Lei, Yaguo; Han, Dong; Lin, Jing; He, Zhengjia

    2013-07-01

    Planetary gearboxes are widely used in aerospace, automotive and heavy industry applications due to their large transmission ratio, strong load-bearing capacity and high transmission efficiency. The tough operation conditions of heavy duty and intensive impact load may cause gear tooth damage such as fatigue crack and teeth missed etc. The challenging issues in fault diagnosis of planetary gearboxes include selection of sensitive measurement locations, investigation of vibration transmission paths and weak feature extraction. One of them is how to effectively discover the weak characteristics from noisy signals of faulty components in planetary gearboxes. To address the issue in fault diagnosis of planetary gearboxes, an adaptive stochastic resonance (ASR) method is proposed in this paper. The ASR method utilizes the optimization ability of ant colony algorithms and adaptively realizes the optimal stochastic resonance system matching input signals. Using the ASR method, the noise may be weakened and weak characteristics highlighted, and therefore the faults can be diagnosed accurately. A planetary gearbox test rig is established and experiments with sun gear faults including a chipped tooth and a missing tooth are conducted. And the vibration signals are collected under the loaded condition and various motor speeds. The proposed method is used to process the collected signals and the results of feature extraction and fault diagnosis demonstrate its effectiveness.

  1. Fault detection of planetary gearboxes using new diagnostic parameters

    Science.gov (United States)

    Lei, Yaguo; Kong, Detong; Lin, Jing; Zuo, Ming J.

    2012-05-01

    Planetary gearboxes are commonly used in modern industry because of their large transmission ratio and strong load-bearing capacity. They generally work under heavy load and tough working environment and therefore their key components including sun gear, planet gears, ring gear, etc are subject to severe pitting and fatigue crack. Planetary gearboxes significantly differ from fixed-axis gearboxes and exhibit unique behavior, which invalidates the use of the diagnostic parameters developed and suitable for fixed-axis gearboxes. Therefore, there is a need to develop parameters specifically for detecting and diagnosing faults of planetary gearboxes. In this study, two diagnostic parameters are proposed based on the examination of the vibration characteristics of planetary gearboxes in both time and frequency domains. One is the root mean square of the filtered signal (FRMS) and the other is the normalized summation of positive amplitudes of the difference spectrum between the unknown signal and the healthy signal (NSDS). To test the proposed diagnostic parameters, we conducted experiments on a planetary gearbox test rig with sun gear faults including a cracked tooth and a pitted tooth. The vibration signals were measured under different motor speeds. The proposed parameters are compared with the existing parameters reported in the literature. The comparison results show the proposed diagnostic parameters perform better than others.

  2. Fluvial geomorphology on Earth-like planetary surfaces: A review.

    Science.gov (United States)

    Baker, Victor R; Hamilton, Christopher W; Burr, Devon M; Gulick, Virginia C; Komatsu, Goro; Luo, Wei; Rice, James W; Rodriguez, J A P

    2015-09-15

    Morphological evidence for ancient channelized flows (fluvial and fluvial-like landforms) exists on the surfaces of all of the inner planets and on some of the satellites of the Solar System. In some cases, the relevant fluid flows are related to a planetary evolution that involves the global cycling of a volatile component (water for Earth and Mars; methane for Saturn's moon Titan). In other cases, as on Mercury, Venus, Earth's moon, and Jupiter's moon Io, the flows were of highly fluid lava. The discovery, in 1972, of what are now known to be fluvial channels and valleys on Mars sparked a major controversy over the role of water in shaping the surface of that planet. The recognition of the fluvial character of these features has opened unresolved fundamental questions about the geological history of water on Mars, including the presence of an ancient ocean and the operation of a hydrological cycle during the earliest phases of planetary history. Other fundamental questions posed by fluvial and fluvial-like features on planetary bodies include the possible erosive action of large-scale outpourings of very fluid lavas, such as those that may have produced the remarkable canali forms on Venus; the ability of exotic fluids, such as methane, to create fluvial-like landforms, as observed on Saturn's moon, Titan; and the nature of sedimentation and erosion under different conditions of planetary surface gravity. Planetary fluvial geomorphology also illustrates fundamental epistemological and methodological issues, including the role of analogy in geomorphological/geological inquiry.

  3. Planetary science. Shock compression of stishovite and melting of silica at planetary interior conditions.

    Science.gov (United States)

    Millot, M; Dubrovinskaia, N; Černok, A; Blaha, S; Dubrovinsky, L; Braun, D G; Celliers, P M; Collins, G W; Eggert, J H; Jeanloz, R

    2015-01-23

    Deep inside planets, extreme density, pressure, and temperature strongly modify the properties of the constituent materials. In particular, how much heat solids can sustain before melting under pressure is key to determining a planet's internal structure and evolution. We report laser-driven shock experiments on fused silica, α-quartz, and stishovite yielding equation-of-state and electronic conductivity data at unprecedented conditions and showing that the melting temperature of SiO2 rises to 8300 K at a pressure of 500 gigapascals, comparable to the core-mantle boundary conditions for a 5-Earth mass super-Earth. We show that mantle silicates and core metal have comparable melting temperatures above 500 to 700 gigapascals, which could favor long-lived magma oceans for large terrestrial planets with implications for planetary magnetic-field generation in silicate magma layers deep inside such planets. Copyright © 2015, American Association for the Advancement of Science.

  4. Incorporating Spectra Into Periodic Timing

    Science.gov (United States)

    Connors, Alanna; Hong, J.; Protopapas, P.; Kashyap, V.

    2011-09-01

    The Chandra surveys have resulted in a wealth of data on low-luminosity X-ray sources (Lx 1030-34 erg/s) of Galactic scales beyond the local solar neighborhood. Many of these are compact binaries, in particular, cataclysmic variables, often identified by their periodic X-ray variability and spectra. Hong et al. (2009, 2011) have used energy quantiles (Hong, Schlegel & Grindlay, 2004) as a fast, robust indicator of spectral hardness and absorption of the X-ray sources. Energy quantiles also enable a simple but effective illustration of spectral changes with phase in these periodic systems: e.g. absorption by the accreting material is understood to drive the periodic light-curves. An interesting question is how to best make use of the information encapsulated in the periodic change in energy spectrum, along with the periodic change in intensity, especially for cases of ambiguous period determination? And, how to do it computationally efficiently? A first approach is to do the period search in intensity, as is standard; and then use a criterion of spectral variation to verify possible periods. Huijse, Zegers & Protopapas (2011) recently demonstrated a powerful period estimation technique using information potential and correntropy embedded in the light curve. Similar quantities based on energies (or energy quantiles) of X-ray photons can serve as criteria of spectral variation. A different approach treats the spectrum variations and intensity variations completely independently, searching through period-space in each, and then combining the results. A more general method would include both at the same time, looking for statistically significant variations above what is expected for a constant (in intensity and spectrum).

  5. Area spectra of near extremal black holes

    International Nuclear Information System (INIS)

    Chen, Deyou; Yang, Haitang; Zu, Xiaotao

    2010-01-01

    Motivated by Maggiore's new interpretation of quasinormal modes, we investigate area spectra of a near extremal Schwarzschild-de Sitter black hole and a higher-dimensional near extremal Reissner-Nordstrom-de Sitter black hole. The result shows that the area spectra are equally spaced and irrelevant to the parameters of the black holes. (orig.)

  6. Resolution enhancement in second-derivative spectra.

    Science.gov (United States)

    Czarnecki, Mirosław A

    2015-01-01

    Derivative spectroscopy is a powerful tool for the resolution enhancement in infrared, near-infrared, Raman, ultraviolet-visible, nuclear magnetic resonance, electron paramagnetic resonance, and fluorescence spectroscopy. Despite its great significance in analytical chemistry, not all aspects of the applications of this method have been explored as yet. This is the first systematic study of the parameters that influence the resolution enhancement in the second derivative spectra. The derivative spectra were calculated with the Savitzky-Golay method with different window size (5, 15, 25) and polynomial order (2, 4). The results obtained in this work show that the resolution enhancement in the second derivative spectra strongly depends on the data spacing in the original spectra, window size, polynomial order, and peak profile. As shown, the resolution enhancement is related to variations in the width of the peaks upon the differentiation. The present study reveals that in order to maximize the separation of the peaks in the second derivative spectra, the original spectra should be recorded at high resolution and differentiated using a small window size and high polynomial order. However, working with the real spectra one has to compromise between the noise reduction and optimization of the resolution enhancement in the second derivative spectra.

  7. Aircraft Measurements of Atmospheric Kinetic Energy Spectra

    DEFF Research Database (Denmark)

    Lundtang Petersen, Erik; Lilly, D. K.

    1983-01-01

    Wind velocity data obtained from a jet airliner are used to construct kinetic energy spectra over the range of wavelengths from 2.5 to 2500 km. The spectra exhibit an approximate -5/3 slope for wavelengths of less than about 150 km, steepening to about -2.2 at larger scales. These results support...

  8. Spectra of Velocity components over Complex Terrain

    DEFF Research Database (Denmark)

    Panofsky, H. A.; Larko, D.; Lipschut, R.

    1982-01-01

    Spectra have been measured over a variety of types of complex terrain: on tops of hills and escarpments, over land downstream of a water surface, and over rolling terrain. Differences between spectra over many types of complex terrain, and over uniform terrain, can be explained by these hypothese...

  9. Thermoluminescence spectra measured with a Michelson interferometer

    International Nuclear Information System (INIS)

    Haschberger, P.

    1991-01-01

    A Michelson interferometer was redesigned to prove its capabilities in the measurement of short-lived, low-intensity thermoluminescence spectra. Interferograms are collected during heating up the thermoluminescent probe in a heater plate. A personal computer controls the data acquisition and processes the Fourier transform. As the results show, even a comparatively simple and limited setup leads to relevant and reproducible spectra. (author)

  10. The NASA Regional Planetary Image Facility (RPIF) Network: A Key Resource for Accessing and Using Planetary Spatial Data

    Science.gov (United States)

    Hagerty, J. J.

    2017-12-01

    The role of the NASA Regional Planetary Image Facility (RPIF) Network is evolving as new science-ready spatial data products continue to be created and as key historical planetary data sets are digitized. Specifically, the RPIF Network is poised to serve specialized knowledge and services in a user-friendly manner that removes most barriers to locating, accessing, and exploiting planetary spatial data, thus providing a critical data access role within a spatial data infrastructure. The goal of the Network is to provide support and training to a broad audience of planetary spatial data users. In an effort to meet the planetary science community's evolving needs, we are focusing on the following objectives: Maintain and improve the delivery of historical data accumulated over the past four decades so as not to lose critical, historical information. This is being achieved by systematically digitizing fragile materials, allowing increased access and preserving them at the same time. Help users locate, access, visualize, and exploit planetary science data. Many of the facilities have begun to establish Guest User Facilities that allow researchers to use and/or be trained on GIS equipment and other specialized tools like Socet Set/GXP photogrammetry workstations for generating digital elevation maps. Improve the connection between the Network nodes while also leveraging the unique resources of each node. To achieve this goal, each facility is developing and sharing searchable databases of their collections, including robust metadata in a standards compliant way. Communicate more effectively and regularly with the planetary science community in an effort to make potential users aware of resources and services provided by the Network, while also engaging community members in discussions about community needs. Provide a regional resource for the science community, colleges, universities, museums, media, and the public to access planetary data. Introduce new strategies for

  11. Statistical and physical study of one-sided planetary nebulae.

    Science.gov (United States)

    Ali, A.; El-Nawawy, M. S.; Pfleiderer, J.

    The authors have investigated the spatial orientation of one-sided planetary nebulae. Most of them if not all are interacting with the interstellar medium. Seventy percent of the nebulae in the sample have inclination angles larger than 45° to the Galactic plane and 30% of the inclination angles are less than 45°. Most of the selected objects are old, evolved planetary nebulae with large dimensions, and not far away from the Galactic plane. Seventy-five percent of the objects are within 160 pc from the Galactic plane. The enhanced concavity arc can be explained physically as a result of the 'planetary nebulae-interstellar matter' interaction. The authors discuss the possible effect of the interstellar magnetic field in the concavity regions.

  12. Alien skies planetary atmospheres from earth to exoplanets

    CERN Document Server

    Pont, Frédéric J

    2014-01-01

    Planetary atmospheres are complex and evolving entities, as mankind is rapidly coming to realise whilst attempting to understand, forecast and mitigate human-induced climate change. In the Solar System, our neighbours Venus and Mars provide striking examples of two endpoints of planetary evolution, runaway greenhouse and loss of atmosphere to space. The variety of extra-solar planets brings a wider angle to the issue: from scorching "hot jupiters'' to ocean worlds, exo-atmospheres explore many configurations unknown in the Solar System, such as iron clouds, silicate rains, extreme plate tectonics, and steam volcanoes. Exoplanetary atmospheres have recently become accessible to observations. This book puts our own climate in the wider context of the trials and tribulations of planetary atmospheres. Based on cutting-edge research, it uses a grand tour of the atmospheres of other planets to shine a new light on our own atmosphere, and its relation with life.

  13. Data Preservation and Curation for the Planetary Science Community

    Science.gov (United States)

    Hughes, J. S.; Crichton, D. J.; Joyner, R.; Hardman, S.; Rye, E.

    2013-12-01

    The Planetary Data System (PDS) has just released PDS4 Version 1.0, its next generation data standards for the planetary science archive. These data standards are the result of a multi-year effort to develop an information model based on accepted standards for data preservation, data curation, metadata management, and model development. The resulting information model is subsequently used to drive information system development from the generation of data standards documentation to the configuration of federated registries and search engines. This paper will provide an overview of the development of the PDS4 Information Model and focus on the application of the Open Archive Information System (OAIS) Reference Model - ISO 14721:2003, the Metadata Registry (MDR) Standard - ISO/IEC 11179, and the E-Business XML Standard to help ensure the long-term preservation and curation of planetary science data. Copyright 2013 California Institute of Technology Government sponsorship acknowledged

  14. Evolution of space drones for planetary exploration: A review

    Science.gov (United States)

    Hassanalian, M.; Rice, D.; Abdelkefi, A.

    2018-02-01

    In the past decade, there has been a tendency to design and fabricate drones which can perform planetary exploration. Generally, there are various ways to study space objects, such as the application of telescopes and satellites, launching robots and rovers, and sending astronauts to the targeted solar bodies. However, due to the advantages of drones compared to other approaches in planetary exploration, ample research has been carried out by different space agencies in the world, including NASA to apply drones in other solar bodies. In this review paper, several studies which have been performed on space drones for planetary exploration are consolidated and discussed. Design and fabrication challenges of space drones, existing methods for their flight tests, different methods for deployment and planet entry, and various navigation and control approaches are reviewed and discussed elaborately. Limitations of applying space drones, proposed solutions for future space drones, and recommendations are also presented and discussed.

  15. On the evolution of central stars of planetary nebulae

    International Nuclear Information System (INIS)

    Yahel, R.Z.

    1977-01-01

    The evolution of nuclei of planetary nebulae has been calculated from the end of the ejection stage that produces the nebulae to the white dwarf stage. The structure of the central star is in agreement with the general picture of Finzi (1973) about the mass ejection from the progenitors of planetary nebulae. It has been found that in order to obtain evolutionary track consistent with the Harman-Seaton track (O'Dell, 1968) one has to assume that the masses of the nuclei stars are less than approximately 0.7 solar masses. The calculated evolutionary time scale of the central stars of planetary nebulae is approximately 2 x 10 4 yr. This time scale is negatively correlated with the stellar mass: the heavier the stellar mass, the shorter the evolutionary time scale. (Auth.)

  16. From red giant to planetary nebula - Dust, asymmetry, and polarization

    International Nuclear Information System (INIS)

    Johnson, J.J.; Jones, T.J.

    1991-01-01

    The polarization characteristics of stars in the stages of evolution from red giant to planetary nebula are investigated. Polarization is found to be a characteristic of the majority of these stars. The maximum observed polarization increases with age as the star evolves up the asymptotic giant branch (AGB) to the protoplanetary nebula phase, where the polarization reaches a maximum. The polarization then decreases as the star further evolves into a planetary nebula. These results indicate that aspherical mass loss is likely to be a continual feature of the late stages of stellar evolution, maintaining a clear continuity throughout the life of a star from the moment it first develops a measurable dust shell. The aspherical morphology seen in planetary nebulae has its origin in an intrinsic property of the star that is present at least as early as its arrival at the base of the AGB. 77 refs

  17. Planetary Gearbox Fault Detection Using Vibration Separation Techniques

    Science.gov (United States)

    Lewicki, David G.; LaBerge, Kelsen E.; Ehinger, Ryan T.; Fetty, Jason

    2011-01-01

    Studies were performed to demonstrate the capability to detect planetary gear and bearing faults in helicopter main-rotor transmissions. The work supported the Operations Support and Sustainment (OSST) program with the U.S. Army Aviation Applied Technology Directorate (AATD) and Bell Helicopter Textron. Vibration data from the OH-58C planetary system were collected on a healthy transmission as well as with various seeded-fault components. Planetary fault detection algorithms were used with the collected data to evaluate fault detection effectiveness. Planet gear tooth cracks and spalls were detectable using the vibration separation techniques. Sun gear tooth cracks were not discernibly detectable from the vibration separation process. Sun gear tooth spall defects were detectable. Ring gear tooth cracks were only clearly detectable by accelerometers located near the crack location or directly across from the crack. Enveloping provided an effective method for planet bearing inner- and outer-race spalling fault detection.

  18. Galactic planetary nebulae and evolution of their nuclei

    International Nuclear Information System (INIS)

    Khromov, G.S.

    1980-01-01

    The galactic system of planetary nebulae is investigated using previously constructed distance scale and kinematics data. A strong effect of observational selection is established, which has the consequence that with increasing distance, ever brighter and younger objects are observed. More accurate determinations of the spatial and surface densities of the planetary nebulae system are obtained as well as a new estimate of their total number in the Galaxy, which is approximately 200,000. New estimates are also made of the masses of the nebulae, the absolute magnitudes of the nebulae and their nuclei, and other physical parameters of these objects. The spatial and kinematic characteristics of the planetary nebulae indicate that they are objects of the old type I population. It is possible that their remote ancestors are main sequence stars of the type B8-A5-F or as yet unidentified objects of the same galactic subsystem

  19. PCA: Principal Component Analysis for spectra modeling

    Science.gov (United States)

    Hurley, Peter D.; Oliver, Seb; Farrah, Duncan; Wang, Lingyu; Efstathiou, Andreas

    2012-07-01

    The mid-infrared spectra of ultraluminous infrared galaxies (ULIRGs) contain a variety of spectral features that can be used as diagnostics to characterize the spectra. However, such diagnostics are biased by our prior prejudices on the origin of the features. Moreover, by using only part of the spectrum they do not utilize the full information content of the spectra. Blind statistical techniques such as principal component analysis (PCA) consider the whole spectrum, find correlated features and separate them out into distinct components. This code, written in IDL, classifies principal components of IRS spectra to define a new classification scheme using 5D Gaussian mixtures modelling. The five PCs and average spectra for the four classifications to classify objects are made available with the code.

  20. General Notes on Processes and Their Spectra

    Directory of Open Access Journals (Sweden)

    Gustav Cepciansky

    2012-01-01

    Full Text Available The frequency spectrum performs one of the main characteristics of a process. The aim of the paper is to show the coherence between the process and its own spectrum and how the behaviour and properties of a process itself can be deduced from its spectrum. Processes are categorized and general principles of their spectra calculation and recognition are given. The main stress is put on power spectra of electric and optic signals, as they also perform a kind of processes. These spectra can be directly measured, observed and examined by means of spectral analyzers and they are very important characteristics which can not be omitted at transmission techniques in telecommunication technologies. Further, the paper also deals with non electric processes, mainly with processes and spectra at mass servicing and how these spectra can be utilised in praxis.

  1. Design spectra development considering short time histories

    International Nuclear Information System (INIS)

    Weiner, E.O.

    1983-01-01

    Two separate programs, MODQKE and MDOF, were written to provide a capability of obtaining equipment spectra from design spectra. MODQKE generates or modifies acceleration histories to conform with design spectra pertaining to, say, a foundation. MDOF is a simple linear modal superposition program that solves for equipment support histories using the design spectra conforming histories as input. Equipment spectra, then, are obtained from the support histories using MODQKE. MODQKE was written to modify or provide new histories with special attention paid to short seismic records. A technique from the open literature was borrowed to generate an initial history that approximates a given response spectrum. Further refinement is done with smoothing cycles in which several correction signals are added to the history in a way that produces a least squares fit between actual and prescribed spectra. Provision is made for history shaping, a baseline correction, and final scaling. MODQKE performance has been demonstrated with seven examples having zero to ten percent damping ratios, and 2.5 seconds to 20 seconds durations and a variety of target spectra. The examples show the program is inexpensive to use. MDOF is a simple modal superposition program. It has no eigensolver, and the user supplies mode shapes, frequencies, and participation factors as input. Floor spectra can be generated from design spectra by using a history from MODQKE that conforms to the design spectrum as input to MDOF. Floor motions from MDOF can be fed back to MODQKE without modification to obtain the floor spectra. A simple example is given to show how equipment mass effects can be incorporated into the MDOF solution. Any transient solution capability can be used to replace MDOF. For example, a direct transient approach may be desirable if both the equipment and floor structures are to be included in the model with different damping fractions. (orig./HP)

  2. Exoplanetary System Dynamics: Planetary Multiplicity and Mass Effects

    Science.gov (United States)

    Isoe, Mari; Kokubo, Eiichiro; Turner, Edwin

    2015-12-01

    Recently numerous systems consisting of multiple exoplanets have been discovered. Using a dataset of 375 systems (500 planets) discovered by the radial velocity method and 365 systems (899 planets) containing planet candidates found by the Kepler Mission, we investigate the dependence of the dynamical structure of planetary systems on their multiplicity and the masses of the member planets. We classify the planetary system by three parameters: planetary multiplicity, planetary mass, and the evolutionary stage of the central star. We normalize planetary masses by the mass of the central star and divide the planets into small and large categories by a cut at $10^{-4}$. The central star is classified into main-sequence or giant according to its evolutionary stage. We focus on the angular momentum deficit (AMD) of the systems and the orbital separation between adjacent planets normalized by their Hill radii. We find that in all categories the system AMD decreases with increasing multiplicity. This suggests that in order for multiple systems to be stable, each planet's orbit must be relatively circular. In addition, we find that the distribution of orbital eccentricities of the massive planets and low-mass planets differs. In particular, only high-mass planets have eccentricities larger than 0.4. In the low-mass systems around main sequence stars, we find that the orbital separation decreases with increasing multiplicity. In addition, the orbital separation around main-sequence stars is wider than that around giants. Furthermore, the minimum orbital separation is about 6.4 for non-resonant pairs. This paper presents the statistical properties of the dynamical structure of multiple planetary systems and discusses their formation.

  3. Unstable Planetary Systems Emerging Out of Gas Disks

    Science.gov (United States)

    Matsumura, Soko; Thommes, Edward W.; Chatterjee, Sourav; Rasio, Frederic A.

    2010-05-01

    The discovery of over 400 extrasolar planets allows us to statistically test our understanding of the formation and dynamics of planetary systems via numerical simulations. Traditional N-body simulations of multiple-planet systems without gas disks have successfully reproduced the eccentricity (e) distribution of the observed systems by assuming that the planetary systems are relatively closely packed when the gas disk dissipates, so that they become dynamically unstable within the stellar lifetime. However, such studies cannot explain the small semimajor axes a of extrasolar planetary systems, if planets are formed, as the standard planet formation theory suggests, beyond the ice line. In this paper, we numerically study the evolution of three-planet systems in dissipating gas disks, and constrain the initial conditions that reproduce the observed a and e distributions simultaneously. We adopt initial conditions that are motivated by the standard planet formation theory, and self-consistently simulate the disk evolution and planet migration, by using a hybrid N-body and one-dimensional gas disk code. We also take into account eccentricity damping, and investigate the effect of saturation of corotation resonances on the evolution of planetary systems. We find that the a distribution is largely determined in a gas disk, while the e distribution is determined after the disk dissipation. We also find that there may be an optimum disk mass which leads to the observed a-e distribution. Our simulations generate a larger fraction of planetary systems trapped in mean-motion resonances (MMRs) than the observations, indicating that the disk's perturbation to the planetary orbits may be important to explain the observed rate of MMRs. We also find a much lower occurrence of planets on retrograde orbits than the current observations of close-in planets suggest.

  4. The complex planetary synchronization structure of the solar system

    Science.gov (United States)

    Scafetta, N.

    2014-01-01

    The complex planetary synchronization structure of the solar system, which since Pythagoras of Samos (ca. 570-495 BC) is known as the music of the spheres, is briefly reviewed from the Renaissance up to contemporary research. Copernicus' heliocentric model from 1543 suggested that the planets of our solar system form a kind of mutually ordered and quasi-synchronized system. From 1596 to 1619 Kepler formulated preliminary mathematical relations of approximate commensurabilities among the planets, which were later reformulated in the Titius-Bode rule (1766-1772), which successfully predicted the orbital position of Ceres and Uranus. Following the discovery of the ~ 11 yr sunspot cycle, in 1859 Wolf suggested that the observed solar variability could be approximately synchronized with the orbital movements of Venus, Earth, Jupiter and Saturn. Modern research has further confirmed that (1) the planetary orbital periods can be approximately deduced from a simple system of resonant frequencies; (2) the solar system oscillates with a specific set of gravitational frequencies, and many of them (e.g., within the range between 3 yr and 100 yr) can be approximately constructed as harmonics of a base period of ~ 178.38 yr; and (3) solar and climate records are also characterized by planetary harmonics from the monthly to the millennial timescales. This short review concludes with an emphasis on the contribution of the author's research on the empirical evidences and physical modeling of both solar and climate variability based on astronomical harmonics. The general conclusion is that the solar system works as a resonator characterized by a specific harmonic planetary structure that also synchronizes the Sun's activity and the Earth's climate. The special issue Pattern in solar variability, their planetary origin and terrestrial impacts (Mörner et al., 2013) further develops the ideas about the planetary-solar-terrestrial interaction with the personal contribution of 10

  5. Techniques for Engaging the Public in Planetary Science

    Science.gov (United States)

    Shupla, Christine; Shaner, Andrew; Smith Hackler, Amanda

    2017-10-01

    Public audiences are often curious about planetary science. Scientists and education and public engagement specialists can leverage this interest to build scientific literacy. This poster will highlight research-based techniques the authors have tested with a variety of audiences, and are disseminating to planetary scientists through trainings.Techniques include:Make it personal. Audiences are interested in personal stories, which can capture the excitement, joy, and challenges that planetary scientists experience in their research. Audiences can learn more about the nature of science by meeting planetary scientists and hearing personal stories about their motivations, interests, and how they conduct research.Share relevant connections. Most audiences have very limited understanding of the solar system and the features and compositions of planetary bodies, but they enjoy learning about those objects they can see at night and factors that connect to their culture or local community.Demonstrate concepts. Some concepts can be clarified with analogies, but others can be demonstrated or modeled with materials. Demonstrations that are messy, loud, or that yield surprising results are particularly good at capturing an audience’s attention, but if they don’t directly relate to the key concept, they can serve as a distraction.Give them a role. Audience participation is an important engagement technique. In a presentation, scientists can invite the audience to respond to questions, pause to share their thoughts with a neighbor, or vote on an answer. Audiences can respond physically to prompts, raising hands, pointing, or clapping, or even moving to different locations in the room.Enable the audience to conduct an activity. People learn best by doing and by teaching others; simple hands-on activities in which the audience is discovering something themselves can be extremely effective at engaging audiences.This poster will cite examples of each technique, resources that

  6. Blind extraction of exoplanetary spectra

    Science.gov (United States)

    Morello, Giuseppe; Waldmann, Ingo; Damiano, Mario; Tinetti, Giovanna

    2016-10-01

    In the last decade, remote sensing spectroscopy enabled characterization of the atmospheres of extrasolar planets. Transmission and emission spectra of tens of transiting exoplanets have been measured with multiple instruments aboard Spitzer and Hubble Space Telescopes as well as ground-based facilities, revealing the presence of chemical species in their atmospheres, and constraining their temperature and pressure profiles.Early analyses were somehow heuristic, leading to some controversies in the literature.A photometric precision of 0.01% is necessary to detect the atmospheric spectral modulations. Current observatories, except Kepler, were not designed to achieve this precision. Data reduction is necessary to minimize the effect of instrument systematics in order to achieve the target precision. In the past, parametric models have extensively been used by most teams to remove correlated noise with the aid of auxiliary information of the instrument, the so-called optical state vectors (OSVs). Such OSVs can include inter- and intra-pixel position of the star or its spectrum, instrument temperatures and inclinations, and/or other parameters. In some cases, different parameterizations led to discrepant results.We recommend the use of blind non-parametric data detrending techniques to overcome those issues. In particular, we adopt Independent Component Analysis (ICA), i.e. a powerful blind source separation (BSS) technique to disentangle the multiple instrument systematics and astrophysical signals in transit/eclipse light curves. ICA does not require a model for the systematics, thence it can be applied to any instrument with little changes, if any. ICA-based algorithms have been applied to Spitzer/IRAC and synthetic observations in photometry (Morello et al. 2014, 2015, 2016; Morello 2015) and to Hubble/WFC3, Hubble/NICMOS and Spitzer/IRS and Hubble/WFC3 in spectroscopy (Damiano, Morello et al., in prep., Waldmann 2012, 2014, Waldmann et al. 2013) with excellent

  7. Planetary protection issues related to human missions to Mars

    Science.gov (United States)

    Debus, A.; Arnould, J.

    2008-09-01

    In accordance with the United Nations Outer Space Treaties [United Nations, Agreement Governing the Activities of States on the Moon and Other Celestial Bodies, UN doc A/RES/34/68, resolution 38/68 of December 1979], currently maintained and promulgated by the Committee on Space Research [COSPAR Planetary Protection Panel, Planetary Protection Policy accepted by the COSPAR Council and Bureau, 20 October 2002, amended 24 March 2005, http://www.cosparhq.org/scistr/PPPolicy.htm], missions exploring the Solar system must meet planetary protection requirements. Planetary protection aims to protect celestial bodies from terrestrial contamination and to protect the Earth environment from potential biological contamination carried by returned samples or space systems that have been in contact with an extraterrestrial environment. From an exobiology perspective, Mars is one of the major targets, and several missions are currently in operation, in transit, or scheduled for its exploration. Some of them include payloads dedicated to the detection of life or traces of life. The next step, over the coming years, will be to return samples from Mars to Earth, with a view to increasing our knowledge in preparation for the first manned mission that is likely to take place within the next few decades. Robotic missions to Mars shall meet planetary protection specifications, currently well documented, and planetary protection programs are implemented in a very reliable manner given that experience in the field spans some 40 years. With regards to sample return missions, a set of stringent requirements has been approved by COSPAR [COSPAR Planetary Protection Panel, Planetary Protection Policy accepted by the COSPAR Council and Bureau, 20 October 2002, amended 24 March 2005, http://www.cosparhq.org/scistr/PPPolicy.htm], and technical challenges must now be overcome in order to preserve the Earth’s biosphere from any eventual contamination risk. In addition to the human dimension of

  8. Public Outreach with NASA Lunar and Planetary Mapping and Modeling

    Science.gov (United States)

    Law, E.; Day, B.

    2017-09-01

    NASA's Trek family of online portals is an exceptional collection of resources making it easy for students and the public to explore surfaces of planetary bodies using real data from real missions. Exotic landforms on other worlds and our plans to explore them provide inspiring context for science and technology lessons in classrooms, museums, and at home. These portals can be of great value to formal and informal educators, as well as to scientists working to share the excitement of the latest developments in planetary science, and can significantly enhance visibility and public engagement in missions of exploration.

  9. Application of numerical methods to planetary radiowave scattering

    Science.gov (United States)

    Simpson, Richard A.; Tyler, G. Leonard

    1987-01-01

    Existing numerical techniques for the solution of scattering problems were investigated to determine those which might be applicable to planetary surface studies, with the goal of improving the interpretation of radar data from Venus, Mars, the Moon, and icy satellites. The general characteristics of the models are described along with computational concerns. In particular, the Numerical Electrogmatics Code (NEC) developed at the Lawrence Livermore Laboratory is discussed. Though not developed for random rough surfaces, the NEC contains elements which may be generalized and which could be valuable in the study of scattering by planetary surfaces.

  10. Application of high explosion cratering data to planetary problems

    Science.gov (United States)

    Oberbeck, V. R.

    1977-01-01

    The present paper deals with the conditions of explosion or nuclear cratering required to simulate impact crater formation. Some planetary problems associated with three different aspects of crater formation are discussed, and solutions based on high-explosion data are proposed. Structures of impact craters and some selected explosion craters formed in layered media are examined and are related to the structure of lunar basins. The mode of ejection of material from impact craters is identified using explosion analogs. The ejection mode is shown to have important implications for the origin of material in crater and basin deposits. Equally important are the populations of secondary craters on lunar and planetary surfaces.

  11. Room-temperature semiconductors and scintillators for planetary instruments

    CERN Document Server

    Schweitzer, J S

    1999-01-01

    Room temperature semiconductors introduce some exciting potential for use in instruments designed for planetary measurements. It is important, however, to consider carefully the different types of measurement environments. In some cases room temperature semiconductors provide significant advantages over scintillators, while in some cases scintillators still have advantages over room temperature semiconductors. A number of instrumentation applications for detecting X-rays and gamma rays are considered. By focusing on the physical properties of both types of detectors, it is possible to better understand how each type of detector can best be used for measurements from satellites and directly on planetary bodies.

  12. Radiation protection for human interplanetary spaceflight and planetary surface operations

    Energy Technology Data Exchange (ETDEWEB)

    Clark, B.C. [Armed Forces Radiobiology Research Inst., Bethesda, MD (United States)]|[DLR Inst. of Aerospace Medicine, Cologne (Germany)]|[NASA, Goddard Space Flight Center, Greenbelt, MD (United States)

    1993-12-31

    Radiation protection issues are reviewed for five categories of radiation exposure during human missions to the moon and Mars: trapped radiation belts, galactic cosmic rays, solar flare particle events, planetary surface emissions, and on-board radiation sources. Relative hazards are dependent upon spacecraft and vehicle configurations, flight trajectories, human susceptibility, shielding effectiveness, monitoring and warning systems, and other factors. Crew cabins, interplanetary mission modules, surface habitats, planetary rovers, and extravehicular mobility units (spacesuits) provide various degrees of protection. Countermeasures that may be taken are reviewed relative to added complexity and risks that they could entail, with suggestions for future research and analysis.

  13. On the new modes of planetary-scale electromagnetic waves in the ionosphere

    Directory of Open Access Journals (Sweden)

    G. D. Aburjania

    2004-04-01

    Full Text Available Using an analogy method the frequencies of new modes of the electromagnetic planetary-scale waves (with a wavelength of 103 km or more, having a weather forming nature, are found at different ionospheric altitudes. This method gives the possibility to determine spectra of ionospheric electromagnetic perturbations directly from the dynamic equations without solving the general dispersion equation. It is shown that the permanently acting factor-latitude variation of the geomagnetic field generates fast and slow weakly damping planetary electromagnetic waves in both the E- and F-layers of the ionosphere. The waves propagate eastward and westward along the parallels. The fast waves have phase velocities (1–5km s–1 and frequencies (10–1–10–4, and the slow waves propagate with velocities of the local winds with frequencies (10–4–10–6s–1 and are generated in the E-region of the ionosphere. Fast waves having phase velocities (10-1500km s–1 and frequencies (1–10–3s–1 are generated in the F-region of the ionosphere. The waves generate the geomagnetic pulsations of the order of one hundred nanoTesla by magnitude. The properties and parameters of the theoretically studied electromagnetic waves agree with those of large-scale ultra-low frequency perturbations observed experimentally in the ionosphere.

    Key words. Ionosphere (ionospheric disturbances; waves propagation; ionosphere atmosphere interactions

  14. Precise masses for the transiting planetary system HD 106315 with HARPS

    Science.gov (United States)

    Barros, S. C. C.; Gosselin, H.; Lillo-Box, J.; Bayliss, D.; Delgado Mena, E.; Brugger, B.; Santerne, A.; Armstrong, D. J.; Adibekyan, V.; Armstrong, J. D.; Barrado, D.; Bento, J.; Boisse, I.; Bonomo, A. S.; Bouchy, F.; Brown, D. J. A.; Cochran, W. D.; Collier Cameron, A.; Deleuil, M.; Demangeon, O.; Díaz, R. F.; Doyle, A.; Dumusque, X.; Ehrenreich, D.; Espinoza, N.; Faedi, F.; Faria, J. P.; Figueira, P.; Foxell, E.; Hébrard, G.; Hojjatpanah, S.; Jackman, J.; Lendl, M.; Ligi, R.; Lovis, C.; Melo, C.; Mousis, O.; Neal, J. J.; Osborn, H. P.; Pollacco, D.; Santos, N. C.; Sefako, R.; Shporer, A.; Sousa, S. G.; Triaud, A. H. M. J.; Udry, S.; Vigan, A.; Wyttenbach, A.

    2017-12-01

    Context. The multi-planetary system HD 106315 was recently found in K2 data. The planets have periods of Pb 9.55 and Pc 21.06 days, and radii of rb = 2.44 ± 0.17 R⊕ and rc = 4.35 ± 0.23 R⊕ . The brightness of the host star (V = 9.0 mag) makes it an excellent target for transmission spectroscopy. However, to interpret transmission spectra it is crucial to measure the planetary masses. Aims: We obtained high precision radial velocities for HD 106315 to determine the mass of the two transiting planets discovered with Kepler K2. Our successful observation strategy was carefully tailored to mitigate the effect of stellar variability. Methods: We modelled the new radial velocity data together with the K2 transit photometry and a new ground-based partial transit of HD 106315c to derive system parameters. Results: We estimate the mass of HD 106315b to be 12.6 ± 3.2 M⊕ and the density to be 4.7 ± 1.7 g cm-3, while for HD 106315c we estimate a mass of 15.2 ± 3.7 M⊕ and a density of 1.01 ± 0.29 g cm-3. Hence, despite planet c having a radius almost twice as large as planet b, their masses are consistent with one another. Conclusions: We conclude that HD 106315c has a thick hydrogen-helium gaseous envelope. A detailed investigation of HD 106315b using a planetary interior model constrains the core mass fraction to be 5-29%, and the water mass fraction to be 10-50%. An alternative, not considered by our model, is that HD 106315b is composed of a large rocky core with a thick H-He envelope. Transmission spectroscopy of these planets will give insight into their atmospheric compositions and also help constrain their core compositions. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programme 198.C-0168.

  15. Lunar and Planetary Science XXXV: Achondrite Mishmash

    Science.gov (United States)

    2004-01-01

    The session "Achondrite Mishmash" included teh following presentations:Constraining the Formation and Evolution of IAB Irons - High Precision; 40Ar/39Ar Ages on Plagioclase Separates from Silicate Inclusions of the Campo Del Cielo Meteorite; Radiogenic 129-Xenon in Silicate Inclusions in the Campo Del Cielo Iron Meteorite; Significance of Iron Isotope Mineral Fractionation in Pallasite and Iron Meteorites; An Experimental Study of Phosphoran Olivine and Its Significance in Main Group Pallasites; Characterization of the Distribution of Siderophile and Highly Siderophile Elements in the Milton and Eagle Station Pallasites; Relationships Between HED and Mesosiderite Meteorites: An Iron Isotope Perspective; Production Rates for Noble-Gas Isotopes in Eucrites; Evidence for Subsolidus Metasomatism in the Eucrite Parent Body; Possible Contact Metamorphism of the Polymict Eucrite Petersburg; Early and Late Stage Metals and Sulfides in Diogenites; Constraints on the Lithological Variation near the Surface of the HED Planetoid from the Petrology of 91 & 92 Series Antarctic Achondrites; Cosmic Ray Exposure Ages, Ar-Ar Ages, and the Origin and History of Eucrites; Trace Elements Abundances Vs Closure Temperature in Orthopyroxenes from Howardites; The First Mesosiderite-like Clast in a Howardite; 39Ar-40Ar Dating of Unusual Eucrite NWA 011: Is it from Vesta?; Trace Element Systematics of Northwest Africa 011: A "Eucritic" Basalt from a Non-Eucrite Parent Body ; 33S Anomaly in Acapulcoites and Lodranites; Magnetic Force Microscopy of Primitive Achondrites; Experimental Constraints on Ureilite Petrogenesis; Reflectance Spectra of Ureilites: Nature of the Mafic Silicate Absorption Features; Nitrogen and Noble Gases in Two Monomict Ureilites Acfer 277 and FRO 90036 from Hot and Cold Deserts; Solar Noble Gases in the Angrite Parent Body - Evidence from Volcanic Volatiles Trapped in D'Orbigny Glass; Trace Element Distribution Between Phases of the D'Orbigny Angrite ; Petrological

  16. Statistical properties of Fermi GBM GRBs' spectra

    Science.gov (United States)

    Rácz, István I.; Balázs, Lajos G.; Horvath, Istvan; Tóth, L. Viktor; Bagoly, Zsolt

    2018-03-01

    Statistical studies of gamma-ray burst (GRB) spectra may result in important information on the physics of GRBs. The Fermi GBM catalogue contains GRB parameters (peak energy, spectral indices, and intensity) estimated fitting the gamma-ray spectral energy distribution of the total emission (fluence, flnc), and during the time of the peak flux (pflx). Using contingency tables, we studied the relationship of the models best-fitting pflx and flnc time intervals. Our analysis revealed an ordering of the spectra into a power law - Comptonized - smoothly broken power law - Band series. This result was further supported by a correspondence analysis of the pflx and flnc spectra categorical variables. We performed a linear discriminant analysis (LDA) to find a relationship between categorical (spectral) and model independent physical data. LDA resulted in highly significant physical differences among the spectral types, that is more pronounced in the case of the pflx spectra, than for the flnc spectra. We interpreted this difference as caused by the temporal variation of the spectrum during the outburst. This spectral variability is confirmed by the differences in the low-energy spectral index and peak energy, between the pflx and flnc spectra. We found that the synchrotron radiation is significant in GBM spectra. The mean low-energy spectral index is close to the canonical value of α = -2/3 during the peak flux. However, α is ˜ -0.9 for the spectra of the fluences. We interpret this difference as showing that the effect of cooling is important only for the fluence spectra.

  17. Handbook of Monochromatic XPS Spectra, Semiconductors

    Science.gov (United States)

    Crist, B. Vincent

    2000-10-01

    This handbook is one of three containing an invaluable collection of research grade XPS Spectra. Each handbook concentrates on a specific family of materials (the elements and their native oxides, semiconductors and polymers) and is entirely self-contained. The introductory section to each handbook includes comprehensive information about the XPS instrument used, the materials and the advanced methods used to collect the spectra. Energy resolution settings, instrument characteristics, energy referencing methods, traceability, energy scale calibration details and transmission function are all reported. Among the many valuable features included in each of these handbooks are: ? All spectra were measured by using AlK monochromatic X-rays ? All spectra were collected in a self-consistent manner to maximise data reliability and quality ? All peaks in the wide spectra are fully annotated and accompanied by detailed atom % tables that report BEs for each of the labelled peaks ? Each high-energy resolution spectrum is peak-fitted and accompanied by detailed tables containing binding energies, FWHMs and relative percentages. In this volume 'Semiconductors' are contained XPS Spectra from a wide range of semiconductive materials and related materials, a rare tool for scientists and analysts in this area. Exclusive features of this volume include: ? Binding energies are accurate to +/- 0.08eV ? Charge compensation was done with a flood-gun mesh-screen system ? Valence band spectra document the occupied density of states (DOS) and the fundamental electronic nature of the semi-conductive materials analysed ? Analyses were done: "as received", "freshly fractured in air", "ion etched" and "chemically treated" ? Alphabetically organised by chemical abbreviations for ease of locating each material This handbook is an invaluable reference for materials scientists and electrical engineers in industry, academia and government laboratories interested in the analysis of semiconductors

  18. Planetary Quarantine Annual Review, Space Technology and Research, July 1971 - July 1972

    Science.gov (United States)

    1973-01-01

    The effects of planetary quarantine constraints are assessed for advanced missions and unmanned planetary sample return missions. Considered are natural space environment factors, post launch recontamination effects, spacecraft microbial burden estimation and prediction, and spacecraft cleaning and decontamination techniques.

  19. 75 FR 57520 - NASA Advisory Council; Planetary Science Subcommittee; Supporting Research and Technology Working...

    Science.gov (United States)

    2010-09-21

    ... Science Subcommittee; Supporting Research and Technology Working Group; Meeting AGENCY: National... announces a meeting of the Supporting Research and Technology Working Group of the Planetary Science... INFORMATION CONTACT: Dr. Michael New, Planetary Science Division, National Aeronautics and Space...

  20. Comparative investigation of the energetic ion spectra comprising the magnetospheric ring currents of the solar system

    Science.gov (United States)

    Mauk, B H

    2014-01-01

    Investigated here are factors that control the intensities and shapes of energetic ion spectra that make up the ring current populations of the strongly magnetized planets of the solar system, specifically those of Earth, Jupiter, Saturn, Uranus, and Neptune. Following a previous and similar comparative investigation of radiation belt electrons, we here turn our attention to ions. Specifically, we examine the possible role of the differential ion Kennel-Petschek limit, as moderated by Electromagnetic Ion Cyclotron (EMIC) waves, as a standard for comparing the most intense ion spectra within the strongly magnetized planetary magnetospheres. In carrying out this investigation, the substantial complexities engendered by the very different ion composition distributions of these diverse magnetospheres must be addressed, given that the dispersion properties of the EMIC waves are strongly determined by the ion composition of the plasmas within which the waves propagate. Chosen for comparison are the ion spectra within these systems that are the most intense observed, specifically at 100 keV and 1 MeV. We find that Earth and Jupiter are unique in having their most intense ion spectra likely limited and sculpted by the Kennel-Petschek process. The ion spectra of Saturn, Uranus, and Neptune reside far below their respective limits and are likely limited by interactions with gas and dust (Saturn) and by the absence of robust ion acceleration processes (Uranus and Neptune). Suggestions are provided for further testing the efficacy of the differential Kennel-Petschek limit for ions using the Van Allen Probes. PMID:26167438