29 results on '"Satellites de Glace"'
Number of results to display per page
Search Results
2. Titan : preliminary results on surface properties and photometry from VIMS observations of the early flybys
- Author
-
B. J., Buratti, Sotin, C., Rh., Brown, M.D., Hicks, Clark, R., J.A., Mosher, Cord T.B., Mc, Jaumann, R., K. H., Baines, P. D., Nicholson, Momary, T., D.P., Simonelli, Sicardy, B., Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Satellites de Glace - Published
- 2006
3. Composition and Physical Properties of Enceladus' Surface
- Author
-
Christophe Sotin, Priscilla Cerroni, Dennis L. Matson, Jason W. Barnes, P. D. Nicholson, Dale P. Cruikshank, Ralf Jaumann, Bruno Sicardy, Giancarlo Bellucci, Robert M. Nelson, Bonnie J. Buratti, Thomas B. McCord, S. Newman, R. N. Clark, James M. Bauer, Yves Langevin, M. Combes, Vittorio Formisano, Pierre Drossart, Robert H. Brown, Rachel Mastrapa, Kevin H. Baines, Tom Momary, Fabrizio Capaccioni, Angioletta Coradini, Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Lunar and Planetary Laboratory [University of Arizona] (LPL), University of Arizona, US Geological Survey, Flagstaff, Jet Propulsion Laboratory, California Institute of Technology (JPL), SETI Institute, NASA Ames Research Center, Moffett Field, Istituto di Fisica dello Spazio Interplanetario (IFSI), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Instituto di Astrofisica Spaziale - CNR, Area della recerca di Tor Vergata, Observatoire de Paris, Université Paris sciences et lettres (PSL), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Pôle Planétologie du LESIA, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut d'astrophysique spatiale (IAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Department of Earth and Space Sciences, University of Washington, Department of Astronomy, Cornell University, and Université de Nantes (UN)
- Subjects
Surface (mathematics) ,Materials science ,Extraterrestrial Environment ,Spectrophotometry, Infrared ,010504 meteorology & atmospheric sciences ,Infrared ,Saturnian satellites ,01 natural sciences ,Astrobiology ,Enceladus ,Ammonia ,0103 physical sciences ,VIMS ,Ice Cover ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences ,Multidisciplinary ,Spectrometer ,Atmosphere ,Ice ,surface composition ,Carbon Dioxide ,Amorphous solid ,Satellites de Glace ,Saturn ,13. Climate action ,Cassini ,Satellite ,Water ice ,Atmospheric column ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] - Abstract
Observations of Saturn's satellite Enceladus using Cassini's Visual and Infrared Mapping Spectrometer instrument were obtained during three flybys of Enceladus in 2005. Enceladus' surface is composed mostly of nearly pure water ice except near its south pole, where there are light organics, CO 2 , and amorphous and crystalline water ice, particularly in the region dubbed the âtiger stripes.â An upper limit of 5 precipitable nanometers is derived for CO in the atmospheric column above Enceladus, and 2% for NH 3 in global surface deposits. Upper limits of 140 kelvin (for a filled pixel) are derived for the temperatures in the tiger stripes.
- Published
- 2006
- Full Text
- View/download PDF
4. Curve mass/radius for extrasolar Earth-like planets and ocean planets
- Author
-
Grasset, O., Mocquet, A., Sotin, C., Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Satellites de Glace ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
- Published
- 2006
5. On the Discovery of CO Nighttime Emissions on Titan by Cassini/VIMS : Derived Stratospheric Abundances and Geological Implications
- Author
-
Baines, K.H., Drossart, P., Lopez-Vlaverde, M.A., Atreya, S.K., Sotin, C., Momary, T., Brown, R.H., Buratti, B.J., Clark, R., Nicholson, P.D., Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Satellites de Glace - Published
- 2006
6. Photometric properties of Titan's surface from Cassini VIMS : Relevance to titan's hemispherical albedo dichotomy and surface stability
- Author
-
Kevin H. Baines, L. W. Kamp, P. D. Nicholson, Christophe Sotin, M. Combes, Giancarlo Bellucci, Thomas B. McCord, Bruce Hapke, Dale P. Cruikshank, Fabrizio Capaccioni, Pierre Drossart, William D. Smythe, Roger N. Clark, M. D. Boryta, Ralf Jaumann, Vittorio Formisano, Robert M. Nelson, Robert H. Brown, Jean-Pierre Bibring, Vito Mennella, Bruno Sicardy, B. J. Buratti, Yves Langevin, Dennis L. Matson, Priscilla Cerroni, F. Leader, Angioletta Coradini, Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Jet Propulsion Laboratory, California Institute of Technology (JPL), University of Arizona, University of Pittsburgh, Mount San Antonio College, Walnut, Istituto di Astrofisica Spaziale e Fisica Cosmica (IASF-Roma), Université Paris-Sud - Paris 11 (UP11), US Geological Survey, Denver, Observatoire de Paris, Université Paris sciences et lettres (PSL), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Pôle Planétologie du LESIA, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), National Aeronautics and Space Administration, Ames Research Center, Department of Planetary Exploration, DLR, University of Hawaii, INAF-Osservatorio Astronomico di Capodimonte (INAF-OAC), Department of Astronomy, Cornell University, and Université de Nantes (UN)
- Subjects
Brightness ,medicine.medical_specialty ,Haze ,010504 meteorology & atmospheric sciences ,Astrophysics ,01 natural sciences ,Astrobiology ,law.invention ,Orbiter ,symbols.namesake ,Impact crater ,law ,0103 physical sciences ,medicine ,Specular reflection ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences ,Astronomy and Astrophysics ,Spectral imaging ,Satellites de Glace ,13. Climate action ,Space and Planetary Science ,symbols ,Titan (rocket family) ,Longitude ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Geology - Abstract
International audience; The Visual and Infrared Mapping Spectrometer (VIMS) instrument on the Cassini Saturn Orbiter returned spectral imaging data as the spacecraft undertook six close encounters with Titan beginning 7 July, 2004. Three of these flybys each produced overlapping coverage of two distinct regions of Titan's surface. Twenty-four points were selected on approximately opposite hemispheres to serve as photometric controls. Six points were selected in each of four reflectance classes. On one hemisphere each control point was observed at three distinct phase angles. From the derived phase coefficients, preliminary normal reflectances were derived for each reflectance class. The normal reflectance of Titan's surface units at 2.0178 mum ranged from 0.079 to 0.185 for the most absorbing to the most reflective units assuming no contribution from absorbing haze. When a modest haze contribution of tau=0.1 is considered these numbers increase to 0.089-0.215. We find that the lowest three reflectance classes have comparable normal reflectance on either hemisphere. However, for the highest brightness class the normal reflectance is higher on the hemisphere encompassing longitude 14-65° compared to the same high brightness class for the hemisphere encompassing 122-156° longitude. We conclude that an albedo dichotomy observed in continental sized units on Titan is due not only to one unit having more areal coverage of reflective material than the other but the material on the brighter unit is intrinsically more reflective than the most reflective material on the other unit. This suggests that surface renewal processes are more widespread on Titan's more reflective units than on its less reflective units. We note that one of our photometric control points has increased in reflectance by 12% relative to the surrounding terrain from July of 2004 to April and May of 2005. Possible causes of this effect include atmospheric processes such as ground fog or orographic clouds; the suggestion of active volcanism cannot be ruled out. Several interesting circular features which resembled impact craters were identified on Titan's surface at the time of the initial Titan flyby in July of 2004. We traced photometric profiles through two of these candidate craters and attempted to fit these profiles to the photometric properties expected from model depressions. We find that the best-fit attempt to model these features as craters requires that they be unrealistically deep, approximately 70 km deep. We conclude that despite their appearance, these circular features are not craters, however, the possibility that they are palimpsests cannot be ruled out. We used two methods to test for the presence of vast expanses of liquids on Titan's surface that had been suggested to resemble oceans. Specular reflection of sunlight would be indicative of widespread liquids on the surface; we found no evidence of this. A large liquid body should also show uniformity in photometric profile; we found the profiles to be highly variable. The lack of specular reflection and the high photometric variability in the profiles across candidate oceans is inconsistent with the presence of vast expanses of flat-lying liquids on Titan's surface. While liquid accumulation may be present as small, sub-pixel-sized bodies, or in areas of the surface which still remain to be observed by VIMS, the presence of large ocean-sized accumulations of liquids can be ruled out. The Cassini orbital tour offers the opportunity for VIMS to image the same parts of Titan's surface repeatedly at many different illumination and observation geometries. This creates the possibility of understanding the properties of Titan's atmosphere and haze by iteratively adapting models to create a best fit to the surface reflectance properties.
- Published
- 2006
- Full Text
- View/download PDF
7. Raman study of high pressure clathrate hydrates up to 1.2 GPa
- Author
-
Choukroun, M., Morizet, Y., Grasset, O., Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Satellites de Glace - Published
- 2006
8. On the Possible Properties of Small and Cold Extrasolar Planets : Is OGLE-2005-BLG-390Lb Entirely Frozen ?
- Author
-
Ehrenreich, D., Des Etangs A., Lecavelier, J.P., Beaulieu, Grasset, O., Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Satellites de Glace - Published
- 2006
9. Cassini/VIMS hyperspectral observations of the Huygens landing site on Titan
- Author
-
Rodriguez, S., Mouelic S., Le, Sotin, C., Clénet, H., Clark, R., B.J, Buratti, R.H., Brown, Cord T.B., Mc, P.D., Nicholson, K.H., Baines, Science Team, Vims, Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Satellites de Glace - Published
- 2006
10. The Atmospheres of Saturn and Titan in the Near-Infrared First Results of Cassini/vims
- Author
-
Kevin H. Baines, Roger N. Clark, Yves Langevin, Giancarlo Bellucci, Vittorio Formisano, Fabrizio Capaccioni, P. D. Nicholson, V. Mennella, Angioletta Coradini, D. P. Cruikshank, Robert M. Nelson, Caitlin A. Griffith, Robert H. Brown, T. B. McCord, C. Sotin, M. Combes, Jean-Pierre Bibring, B. J. Buratti, Tom Momary, Dennis L. Matson, Priscilla Cerroni, Pierre Drossart, R. Jaumann, Bruno Sicardy, Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Jet Propulsion Laboratory, California Institute of Technology (JPL), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Pôle Planétologie du LESIA, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Istituto di Fisica dello Spazio Interplanetario (IFSI), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Lunar and Planetary Laboratory [University of Arizona] (LPL), University of Arizona, Institut d'astrophysique spatiale (IAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Istituto di Astrofisica Spaziale e Fisica Cosmica (IASF-Roma), US Geological Survey, Flagstaff, Departement de recherche SPAtiale (DESPA), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), SETI Institute, NASA Ames Research Center, Moffett Field, Department of Planetary Exploration, DLR, Department of Earth and Space Sciences, University of Washington, INAF-Osservatorio Astronomico di Capodimonte (INAF-OAC), and Department of Astronomy, Cornell University
- Subjects
Haze ,010504 meteorology & atmospheric sciences ,Atmospheric sciences ,01 natural sciences ,law.invention ,Troposphere ,Atmosphere ,symbols.namesake ,Orbiter ,Planet ,law ,0103 physical sciences ,Earth and Planetary Sciences (miscellaneous) ,Near-Infrared ,VIMS ,Atmosphere of Titan ,010303 astronomy & astrophysics ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences ,Astronomy ,Astronomy and Astrophysics ,Satellites de Glace ,Planetary science ,Saturn ,13. Climate action ,Space and Planetary Science ,symbols ,Cassini ,Titan (rocket family) ,Titan ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Geology - Abstract
International audience; The wide spectral coverage and extensive spatial, temporal, and phase-angle mapping capabilities of the Visual Infrared Mapping Spectrometer (VIMS) onboard the Cassini-Huygens Orbiter are producing fundamental new insights into the nature of the atmospheres of Saturn and Titan. For both bodies, VIMS maps over time and solar phase angles provide information for a multitude of atmospheric constituents and aerosol layers, providing new insights into atmospheric structure and dynamical and chemical processes. For Saturn, salient early results include evidence for phosphine depletion in relatively dark and less cloudy belts at temperate and mid-latitudes compared to the relatively bright and cloudier Equatorial Region, consistent with traditional theories of belts being regions of relative downwelling. Additional Saturn results include (1) the mapping of enhanced trace gas absorptions at the south pole, and (2) the first high phase-angle, high-spatial-resolution imagery of CH4 fluorescence. An additional fundamental new result is the first nighttime near-infrared mapping of Saturn, clearly showing discrete meteorological features relatively deep in the atmosphere beneath the planet's sunlit haze and cloud layers, thus revealing a new dynamical regime at depth where vertical dynamics is relatively more important than zonal dynamics in determining cloud morphology. Zonal wind measurements at deeper levels than previously available are achieved by tracking these features over multiple days, thereby providing measurements of zonal wind shears within Saturn's troposphere when compared to cloudtop movements measured in reflected sunlight. For Titan, initial results include (1) the first detection and mapping of thermal emission spectra of CO, CO2, and CH3D on Titan's nightside limb, (2) the mapping of CH4 fluorescence over the dayside bright limb, extending to ˜ ˜750 km altitude, (3) wind measurements of ˜ ˜0.5 ms-1, favoring prograde, from the movement of a persistent (multiple months) south polar cloud near 88° S latitude, and (4) the imaging of two transient mid-southern-latitude cloud features.
- Published
- 2005
- Full Text
- View/download PDF
11. Titan's internal structure inferred from a coupled thermal-orbital model
- Author
-
Jonathan I. Lunine, Olivier Grasset, Gabriel Tobie, Christophe Sotin, Antoine Mocquet, Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Convection ,Solar System ,010504 meteorology & atmospheric sciences ,Ice Ih ,Orbital eccentricity ,01 natural sciences ,7. Clean energy ,Astrobiology ,symbols.namesake ,0103 physical sciences ,Thermal ,010303 astronomy & astrophysics ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences ,Physics ,Astronomy and Astrophysics ,Mechanics ,Dissipation ,Satellites de Glace ,13. Climate action ,Space and Planetary Science ,Physics::Space Physics ,Heat transfer ,symbols ,Astrophysics::Earth and Planetary Astrophysics ,Titan (rocket family) - Abstract
Through coupled thermal and orbital calculations including a full description of tidal dissipation, heat transfer and the H 2O–NH3 phase diagram, we propose a model for the internal structure and composition of Titan testable with Cassini–Huygens measurements. The high value of Titan’s orbital eccentricity provides a strong constraint on the amount of the tidal energy dissipation on its surface and within its interior since its formation. We show that only models with a few percent of ammonia (and not zero) in the primordial liquid water shell can limit the damping of the eccentricity over the age of the Solar System. The present models predict that a liquid ammonia-rich water layer should still be present within Titan under an ice I layer, a few tens of kilometers thick. Furthermore, we predict that any event linked to convective processes in the ice Ih layer (like the degassing of methane) could have occurred very late in Titan’s history.
- Published
- 2005
12. A 5-Micron-Bright Spot on Titan: Evidence for Surface Diversity
- Author
-
Roger N. Clark, Michael E. Brown, Dale P. Cruikshank, Emily L. Schaller, Jason Perry, Angioletta Coradini, Thomas B. McCord, Alfred S. McEwen, Jason W. Barnes, Elizabeth P. Turtle, Bonnie J. Buratti, Robert H. Brown, Michael Janssen, Yves Langevin, J. Barbara, Henry G. Roe, P. D. Nicholson, Giancarlo Bellucci, Caitlin A. Griffith, Ralf Jaumann, Jean-Pierre Bibring, S. Fussner, Richard West, Christophe Sotin, Vittorio Formisano, Dennis L. Matson, Bruno Sicardy, M. Combes, Kevin H. Baines, Ralph D. Lorenz, Charles Elachi, Pierre Drossart, Fabrizio Capaccioni, A. H. Bouchez, Priscilla Cerroni, Lunar and Planetary Laboratory [University of Arizona] (LPL), University of Arizona, Jet Propulsion Laboratory, California Institute of Technology (JPL), Geological and Planetary Sciences, California Institute of Technology, Pasadena, Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), US Geological Survey, Flagstaff, NASA Goddard Institute for Space Studies, Columbia University, W. M. Keck Observatory, Istituto di Fisica dello Spazio Interplanetario (IFSI), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Institut d'astrophysique spatiale (IAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Istituto di Astrofisica Spaziale e Fisica Cosmica (IASF-Roma), Observatoire de Paris, Université Paris sciences et lettres (PSL), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Pôle Planétologie du LESIA, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), SETI Institute, NASA Ames Research Center, Moffett Field, Institute for Planetary Exploration, Deutsches Zentrum for Luft und Raumfahrt, Department of Earth and Space Sciences, University of Washington, and Department of Astronomy, Cornell University
- Subjects
Extraterrestrial Environment ,010504 meteorology & atmospheric sciences ,Infrared ,01 natural sciences ,Albedo feature ,symbols.namesake ,Optics ,Dry Ice ,0103 physical sciences ,VIMS ,Geophysical Phenomena ,Imaging science ,Spacecraft ,010303 astronomy & astrophysics ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences ,Multidisciplinary ,Spectrometer ,Atmosphere ,business.industry ,Spectrum Analysis ,Ice ,Temperature ,Water ,Astronomy ,Wavelength ,Satellites de Glace ,Saturn ,Bright spot ,infrared ,symbols ,Cassini ,Titan ,business ,Titan (rocket family) ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Methane ,Geology - Abstract
International audience; Observations from the Cassini Visual and Infrared Mapping Spectrometer show an anomalously bright spot on Titan located at 80°W and 20°S. This area is bright in reflected light at all observed wavelengths, but is most noticeable at 5 microns. The spot is associated with a surface albedo feature identified in images taken by the Cassini Imaging Science Subsystem. We discuss various hypotheses about the source of the spot, reaching the conclusion that the spot is probably due to variation in surface composition, perhaps associated with recent geophysical phenomena.
- Published
- 2005
- Full Text
- View/download PDF
13. Tidal dissipation within large icy satellites : Applications to Europa and Titan
- Author
-
Christophe Sotin, Gabriel Tobie, Antoine Mocquet, Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
010504 meteorology & atmospheric sciences ,Meteorology ,Tidal heating ,7. Clean energy ,01 natural sciences ,Mantle (geology) ,Viscoelasticity ,Physics::Geophysics ,chemistry.chemical_compound ,symbols.namesake ,0103 physical sciences ,010303 astronomy & astrophysics ,Physics::Atmospheric and Oceanic Physics ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences ,Physics ,business.industry ,Astronomy and Astrophysics ,Geophysics ,Dissipation ,Strain rate ,Silicate ,Satellites de Glace ,chemistry ,13. Climate action ,Space and Planetary Science ,symbols ,Astrophysics::Earth and Planetary Astrophysics ,business ,Titan (rocket family) ,Tidal power - Abstract
This paper describes a new approach based on variational principles to calculate the radial distribution of tidal energy dissipation in any satellite. The advantage of the model with respect to classical solutions, is that it relates in a straightforward way the radial distribution of the time-averaged dissipation rate to its sensitivity to the corresponding distribution of viscoelastic parameters. This method is applied to Io-, Europa-, and Titan-like interiors, and it is tested against the results obtained by two classical methods by determining global dissipation as well as radial and lateral distributions within satellite interiors. By exploring systematically the different parameters defining the interior models, we demonstrate that the presence of a deep ocean below an outer ice layer strongly influences the tidal dissipation distribution in both the outer ice layer and in the innermost part of the satellite. On the one hand, the ocean by imposing a large radial displacement at the base of the outer ice I layer, controls the distribution of tidal strain rate within the outer layer, making the tidal strain rate field very weakly sensitive to the viscosity variations. Conversely, in the high-pressure ice layer below the ocean, both tidal strain rate and dissipation are very sensitive to any variation of the ice viscosity. On the other hand, for identical structures of the mantle and of the core, the presence of a subsurface ocean reduces the strength of dissipation in the silicate mantle. The existence of a liquid layer within Europa makes models of the silicate mantle less dissipative than the predictions for Io.
- Published
- 2005
14. Pressure measurements within optical cells using diamond sensors: accuracy of the method below 1GPa
- Author
-
M. Choukroun, E. Amiguet, O. Grasset, Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
010504 meteorology & atmospheric sciences ,Analytical chemistry ,02 engineering and technology ,engineering.material ,01 natural sciences ,Diamond anvil cell ,law.invention ,symbols.namesake ,law ,Dispersion (optics) ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences ,Chemistry ,Diamond ,Gauge (firearms) ,Atmospheric temperature range ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Satellites de Glace ,Pressure measurement ,Sapphire ,engineering ,symbols ,Atomic physics ,0210 nano-technology ,Raman spectroscopy - Abstract
The accuracy of the diamond pressure gauge has been investigated in the moderate pressure range (0–1 GPa) between 210 and 310 K. Experiments have been conducted using a sapphire anvil cell coupled to a Raman spectrometer. The temperature shift of the first-order Raman peak of diamond is very small (−7.56×10−4 cm−1/K−1.5), which confirms previous results obtained on a wider temperature range. Such a trend implies a very small shift over the studied temperature range, of the same order than the dispersion due to external factors (isotopic composition, orientation). The pressure dependence is found equal to 3.20 (±0.02) cm−1/GPa. A statistical description of the data is provided, indicating that the diamond gauge provides pressure estimates below 1 GPa with an accuracy of±39 MPa. Application of these results to science fields involved in the moderate pressure range below 1 GPa is discussed.
- Published
- 2005
15. Compositional maps of Saturn's moon Phoebe from imaging spectroscopy
- Author
-
Jean-Pierre Bibring, P. D. Nicholson, Fabrizio Capaccioni, Angioletta Coradini, Vito Mennella, Jonathan I. Lunine, Bonnie J. Buratti, Yves Langevin, Bruno Sicardy, Robert M. Nelson, Todd M. Hoefen, Robert H. Brown, Thomas B. McCord, Kevin H. Baines, Priscilla Cerroni, Dale P. Cruikshank, Vittorio Formisano, Christophe Sotin, Ralf Jaumann, Dennis L. Matson, Giancarlo Bellucci, Gary B. Hansen, Klaus-Dieter Matz, J. M. Curchin, Roger N. Clark, Karl Hibbits, Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Pôle Planétologie du LESIA, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)
- Subjects
Solar System ,010504 meteorology & atmospheric sciences ,Astrophysics::High Energy Astrophysical Phenomena ,Saturnian satellites ,imaging spectroscopy ,01 natural sciences ,Astrobiology ,Saturn's Moon Phoebe ,Saturn ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,Circular orbit ,010303 astronomy & astrophysics ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences ,Multidisciplinary ,Retrograde motion ,Astronomy ,Imaging spectroscopy ,Satellites de Glace ,Phoebe ,13. Climate action ,Physics::Space Physics ,Cassini ,Satellite ,Astrophysics::Earth and Planetary Astrophysics ,Formation and evolution of the Solar System ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Geology - Abstract
The origin of Phoebe, which is the outermost large satellite of Saturn, is of particular interest because its inclined, retrograde orbit suggests that it was gravitationally captured by Saturn, having accreted outside the region of the solar nebula in which Saturn formed. By contrast, Saturn's regular satellites (with prograde, low-inclination, circular orbits) probably accreted within the sub-nebula in which Saturn itself formed. Here we report imaging spectroscopy of Phoebe resulting from the Cassini-Huygens spacecraft encounter on 11 June 2004. We mapped ferrous-iron-bearing minerals, bound water, trapped CO2, probable phyllosilicates, organics, nitriles and cyanide compounds. Detection of these compounds on Phoebe makes it one of the most compositionally diverse objects yet observed in our Solar System. It is likely that Phoebe's surface contains primitive materials from the outer Solar System, indicating a surface of cometary origin.
- Published
- 2005
- Full Text
- View/download PDF
16. Resorption process in Astypalaea Linea extensive region (Europa)
- Author
-
E. Mercier, Loïc Mével, Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), and Programme National de Planétologie, INSU
- Subjects
Morphology ,010504 meteorology & atmospheric sciences ,Galileo ,[PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP] ,01 natural sciences ,Linea ,[SDU.STU.PL]Sciences of the Universe [physics]/Earth Sciences/Planetology ,0103 physical sciences ,Compression (geology) ,Petrology ,010303 astronomy & astrophysics ,Process (anatomy) ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences ,Icy satellites ,Tectonics ,Compression ,Astronomy and Astrophysics ,Crust ,Geophysics ,91.10.Kg ,96.12.-a ,96.12.Xy ,96.30.ld ,91.55.Nc ,Satellites de Glace ,Space and Planetary Science ,Astypalaea Linea ,Europa ,Geology - Abstract
International audience; Whereas numerous extensive features, where new crust is created, are now well recognized on Europa's surface, those relevant to crust disappearance remain difficult to find. This work presents a reconstruction of the surface prior to Astypalaea Linea's emplacement (one of the features where new crustal material appears). We demonstrate that a scattered disappearance of crust takes place in an extensive region close to Astypalaea Linea. Physical processes invoked for disappearance are discussed: pressure melting may be responsible for the mobilization of surface material and its collapse down through the icy crust.
- Published
- 2005
- Full Text
- View/download PDF
17. The ammonia-water system at high pressures: Implications for the methane of Titan
- Author
-
Grasset, O., Pargamin, J., Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Satellites de Glace ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
- Published
- 2005
18. Cassini visual and infrared mapping spectrometer observations of Iapetus: Detection of CO2
- Author
-
Bj., Buratti, Dp., Cruikshank, Rh., Brown, Rn., Clark, Sotin, C., Jm., Bauer, Jaumann, R., Tb., Mccord, Dp., Simonelli, Ca., Hibbitts, Gb., Hansen, Tc., Owen, Kh., Baines, Bellucci, G., Jp., Bibring, Capaccioni, F., Cerroni, P., Coradini, A., Drossart, P., Formisano, V., Langevin, Y., Dl., Matson, Mennella, V., Rm., Nelson, Pd., Nicholson, Sicardy, B., Tl., Roush, Soderlund, K., Muradyan, A., Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Satellites de Glace ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
- Published
- 2005
19. A comparative study of the outer planets before the exploration of Saturn by Cassini/Huygens ; Introduction
- Author
-
Encrenaz, Thérèse, Kallenbach, R., Owen, Tobias C., Sotin, Christophe, Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Departement de recherche SPAtiale (DESPA), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Pôle Planétologie du LESIA, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), International Space Science Institute (ISSI), and University of Hawaii, Manoa
- Subjects
Satellites de Glace ,010504 meteorology & atmospheric sciences ,Space and Planetary Science ,0103 physical sciences ,Astronomy and Astrophysics ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,010303 astronomy & astrophysics ,01 natural sciences ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences - Abstract
International audience; Not Available
- Published
- 2005
- Full Text
- View/download PDF
20. Cassini VIMS observations of the Galilean satellites including the VIMS calibration procedure
- Author
-
Jean-Pierre Bibring, Angioletta Coradini, Yves Langevin, G. B. Hansen, Gianrico Filacchione, P. D. Nicholson, Priscilla Cerroni, Robert M. Nelson, M. Combes, Pierre Drossart, Kevin H. Baines, Bonnie J. Buratti, Fabrizio Capaccioni, Giancarlo Bellucci, Dennis L. Matson, Charles A. Hibbitts, Roger N. Clark, Dale P. Cruikshank, Vittorio Formisano, Robert H. Brown, Thomas B. McCord, Bruno Sicardy, E. Bussoletti, Christophe Sotin, Ralf Jaumann, Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), HIGP/SOEST, University of Hawaii, Istituto Fisica Spazio Interplanetario, INAF, Planetary Science Institute, 22 Fiddler's Rd., Winthrop, Istituto Astrofisica Spaziale e Fisica Cosmica, CNR, US Geological Survey, Denver, Department Planetary Science and LPL, University of AZ, Tucson, Jet Propulsion Laboratory, California Institute of Technology (JPL), Institut d'astrophysique spatiale (IAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), INAF-Osservatorio Astronomico di Capodimonte (INAF-OAC), Departement de recherche SPAtiale (DESPA), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Pôle Planétologie du LESIA, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), NASA Ames Research Center, Astrophysics Branch, Moffett Field, Department of Planetary Exploration, DLR, Department of Astronomy, Cornell University, and Université de Nantes (UN)
- Subjects
010504 meteorology & atmospheric sciences ,Satellite surfaces ,01 natural sciences ,Space mission ,Jovian ,Jupiter ,symbols.namesake ,Saturn ,0103 physical sciences ,010303 astronomy & astrophysics ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences ,Remote sensing ,Spectrometer ,Spacecraft ,business.industry ,Near-infrared spectroscopy ,Astronomy ,Astronomy and Astrophysics ,Galilean satellites ,Galilean moons ,Satellites de Glace ,13. Climate action ,Space and Planetary Science ,Surface composition ,Physics::Space Physics ,symbols ,Astrophysics::Earth and Planetary Astrophysics ,business ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Jupiter system ,Geology ,Data reduction - Abstract
The Visual and Infrared Mapping Spectrometer (VIMS) observed the Galilean satellites during the Cassini spacecraft's 2000/2001 flyby of Jupiter, providing compositional and thermal information about their surfaces. The Cassini spacecraft approached the jovian system no closer than about 126 Jupiter radii, about 9 million kilometers, at a phase angle of
- Published
- 2004
- Full Text
- View/download PDF
21. Principal components analysis of Jupiter VIMS spectra
- Author
-
Ralf Jaumann, Yves Langevin, Bruno Sicardy, G. Hansen, P. D. Nicholson, Thomas B. McCord, Bonnie J. Buratti, Christophe Sotin, M.C. Chamberlain, Roger N. Clark, Vittorio Formisano, Jean-Pierre Bibring, Kevin H. Baines, Robert M. Nelson, Gianrico Filacchione, Mark R. Showalter, Priscilla Cerroni, Pierre Drossart, Emiliano D'Aversa, K. Hibbits, Giancarlo Bellucci, Robert H. Brown, Dennis L. Matson, Dale P. Cruikshank, Vito Mennella, Fabrizio Capaccioni, Angioletta Coradini, Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Istituto di Fisica dello Spazio Interplanetario (IFSI), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Lunar and Planetary Laboratory [University of Arizona] (LPL), University of Arizona, Jet Propulsion Laboratory, California Institute of Technology (JPL), Institut d'astrophysique spatiale (IAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Istituto di Astrofisica Spaziale e Fisica Cosmica (IASF-Roma), US Geological Survey, Flagstaff, SETI Institute, NASA Ames Research Center, Moffett Field, Observatoire de Paris, Université Paris sciences et lettres (PSL), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Pôle Planétologie du LESIA, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Department of Planetary Exploration, DLR, Department of Earth and Space Sciences, University of Washington, INAF-Osservatorio Astronomico di Capodimonte (INAF-OAC), and Department of Astronomy, Cornell University
- Subjects
Atmospheric Science ,010504 meteorology & atmospheric sciences ,Spectrometer ,Channel (digital image) ,Wavelength range ,Aerospace Engineering ,Astronomy and Astrophysics ,Stellar classification ,01 natural sciences ,Spectral line ,Jupiter ,Satellites de Glace ,Geophysics ,Space and Planetary Science ,0103 physical sciences ,Principal component analysis ,General Earth and Planetary Sciences ,Great Red Spot ,Astrophysics::Earth and Planetary Astrophysics ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,010303 astronomy & astrophysics ,Geology ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences ,Remote sensing - Abstract
International audience; During Cassini - Jupiter flyby occurred in December 2000, Visual-Infrared mapping spectrometer (VIMS) instrument took several image cubes of Jupiter at different phase angles and distances. We have analysed the spectral images acquired by the VIMS visual channel by means of a principal component analysis technique (PCA). The original data set consists of 96 spectral images in the 0.35-1.05 mum wavelength range. The product of the analysis are new PC bands, which contain all the spectral variance of the original data. These new components have been used to produce a map of Jupiter made of seven coherent spectral classes. The map confirms previously published work done on the Great Red Spot by using NIMS data. Some other new findings, presently under investigation, are presented.
- Published
- 2004
- Full Text
- View/download PDF
22. The Cassini visual and infrared mapping spectrometer (VIMS) investigation
- Author
-
R. M. Nelson, Jean-Pierre Bibring, P. D. Nicholson, Dale P. Cruikshank, P. Cerroni, Christophe Sotin, Roger N. Clark, V. Formisano, Robert H. Brown, G. Bellucci, T. B. McCord, D. L. Matson, R. Jaumann, Y. Langevin, F. Capaccioni, A. Coradini, B. J. Buratti, E. Miller, Pierre Drossart, Bruno Sicardy, Kevin H. Baines, Vito Mennella, Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Lunar and Planetary Laboratory [University of Arizona] (LPL), University of Arizona, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
010504 meteorology & atmospheric sciences ,biology ,Spectrometer ,Infrared ,Observational techniques ,Astronomy and Astrophysics ,Venus ,biology.organism_classification ,01 natural sciences ,Astrobiology ,symbols.namesake ,Imaging spectroscopy ,Satellites de Glace ,Planetary science ,13. Climate action ,Space and Planetary Science ,0103 physical sciences ,symbols ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Titan (rocket family) ,010303 astronomy & astrophysics ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences ,Remote sensing ,Saturnian system - Abstract
International audience; The Cassini visual and infrared mapping spectrometer (VIMS) investigation is a multidisciplinary study of the Saturnian system. Visual and near-infrared imaging spectroscopy and high-speed spectrophotometry are the observational techniques. The scope of the investigation includes the rings, the surfaces of the icy satellites and Titan, and the atmospheres of Saturn and Titan. In this paper, we will elucidate the major scientific and measurement goals of the investigation, the major characteristics of the Cassini VIMS instrument, the instrument calibration, and operation, and the results of the recent Cassini flybys of Venus and the Earth Moon system.
- Published
- 2004
- Full Text
- View/download PDF
23. Internal structure and dynamics of the large icy satellites
- Author
-
Gabriel Tobie, Christophe Sotin, Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Convection ,geography ,geography.geographical_feature_category ,010504 meteorology & atmospheric sciences ,General Engineering ,Energy Engineering and Power Technology ,Glacier ,Tidal heating ,Icy moon ,01 natural sciences ,Astrobiology ,Galilean moons ,symbols.namesake ,Satellites de Glace ,13. Climate action ,Saturn ,0103 physical sciences ,symbols ,Titan (rocket family) ,Internal heating ,010303 astronomy & astrophysics ,Geology ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences - Abstract
The magnetic data returned by the Galileo mission suggest that deep oceans are present within the icy Galilean satellites. In addition, tectonic features on Europa are consistent with models of subsolidus convection within the outer ice I layer. Ice viscosity is a key parameter for modeling the thermal and orbital evolution of these large satellites. Using laboratory experiments and glacier measurements, this article shows that tidal heating is a strong source of internal heating which may explain the presence of a deep ocean within Europa. Another key parameter is the composition of ice. The presence of ammonia, which is likely in Saturn's sub-nebula, decreases so much the melting point temperature of ice that it would inhibit the complete freezing of the ocean. Predictions for the internal structure of Titan are made and will be checked by the Cassini mission which started orbiting Saturn on 1st July 2004. To cite this article: C. Sotin, G. Tobie, C. R. Physique 5 (2004).
- Published
- 2004
24. Tidally heated convection : Constraints on Europa's ice shell thickness
- Author
-
Gaël Choblet, Gabriel Tobie, Christophe Sotin, Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Convection ,Atmospheric Science ,010504 meteorology & atmospheric sciences ,Convective heat transfer ,Equator ,ice ,Soil Science ,Tidal heating ,Aquatic Science ,Pressure ridge ,Oceanography ,01 natural sciences ,Physics::Geophysics ,Physics::Fluid Dynamics ,Sea ice growth processes ,Geochemistry and Petrology ,0103 physical sciences ,5770 Planetology: Fluid Planets: Tidal forces ,Earth and Planetary Sciences (miscellaneous) ,6218 Planetology: Solar System Objects: Jovian satellites Europa ,010303 astronomy & astrophysics ,Physics::Atmospheric and Oceanic Physics ,0105 earth and related environmental sciences ,Earth-Surface Processes ,Water Science and Technology ,Ecology ,Paleontology ,6020 Planetology: Comets and Small Bodies: Ice ,Forestry ,Geophysics ,equilibrium thickness ,tidal dissipation ,Satellites de Glace ,Heat flux ,13. Climate action ,Space and Planetary Science ,thermal convection ,[SDU]Sciences of the Universe [physics] ,Heat transfer ,5418 Planetology: Solid Surface Planets: Heat flow ,Astrophysics::Earth and Planetary Astrophysics ,5430 Planetology: Solid Surface Planets: Interiors (8147) ,Geology - Abstract
International audience; The thickness of Europa's ice shell is constrained with numerical experiments of thermal convection, including heterogeneous tidal heating. Thermal convection occurs in the stagnant lid regime with most of the tidal heating located in the bottom half of the layer. The addition of tidal heating mainly results in the increase of the temperature of the well-mixed interior and in the decrease of the heat flux at the base of the ice layer. In many simulations, the ice in hot plumes is heated up to its melting point. This induces episodic upwellings (0.5 Ma) of partially molten ice up to the base of the conductive lid, with possible implications for the formation of lenticulae and chaos regions. The thickness of the convective ice shell in equilibrium with the heat flow from the silicate core is estimated to be about 20-25 km. Tidal dissipation and surface temperature variations create lateral variations of the ice shell thickness of about 5 km, with maxima near the equator at the Jovian and anti-Jovian points and minima at midlatitudes. Surface heat flux is about 35-40 mW.m À2 ; it is almost constant all over Europa's surface, even though the tidal dissipation rate is four times larger at the poles than at the equator.
- Published
- 2003
- Full Text
- View/download PDF
25. Cassini-VIMS at Jupiter : Solar occultation measurements using Io
- Author
-
D'Aversa, E., Belluci, G., K.H., Baines, Bellucci, G., Sotin, C., J.-P., Bibring, R.H., Brown, B. J., Buratti, Capaccioni, F., Cerroni, P., R.N., Clark, Coradini, A., D.P., Cruikshank, Drossart, P., Formisano, V., Jaumann, R., Langevin, Y., D.L., Matson, T.B., Mccord, Mennella, V., R.M., Nelson, P.D., Nicholson, Sicardy, B., M.A., Chamberlain, Hansen, G., Hibbitts, K., Showalter, M., Filacchione, G., Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Satellites de Glace ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
- Published
- 2003
26. Impact of aerosols present in Titanﾒs atmosphere on the CASSINI radar experiment
- Author
-
Rodriguez, S., Paillou, Philippe, Dobrijevic, M., Ruffié, G., Coll, P., J.M., Bernard, Encrenaz, P., Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Satellites de Glace ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
- Published
- 2003
27. Observations with the Visual and Infrared Mapping Spectrometer (VIMS) during Cassini's flyby of Jupiter
- Author
-
Vito Mennella, Dale P. Cruikshank, Gianrico Filacchione, Bruno Sicardy, Dennis L. Matson, Bonnie J. Buratti, Yves Langevin, Giancarlo Bellucci, Robert H. Brown, Mark R. Showalter, Ralf Jaumann, Fabrizio Capaccioni, P. D. Nicholson, Thomas B. McCord, G. Hansen, Kevin H. Baines, S. Amici, Roger N. Clark, Vittorio Formisano, Jean-Pierre Bibring, K. Hibbitts, Angioletta Coradini, Pierre Drossart, Matthew A. Chamberlain, Christophe Sotin, Robert M. Nelson, Priscilla Cerroni, Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Pôle Planétologie du LESIA, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)
- Subjects
Physics ,Opposition surge ,Spectrometer ,Infrared ,Imaging spectrometer ,Astronomy ,Astronomy and Astrophysics ,Radius ,Jovian ,Jupiter ,Satellites de Glace ,Space and Planetary Science ,Geometric albedo ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,ComputingMilieux_MISCELLANEOUS - Abstract
The Cassini Visual and Infrared Mapping Spectrometer (VIMS) is an imaging spectrometer covering the wavelength range 0.3–5.2 μm in 352 spectral channels, with a nominal instantaneous field of view of 0.5 mrad. The Cassini flyby of Jupiter represented a unique opportunity to accomplish two important goals: scientific observations of the jovian system and functional tests of the VIMS instrument under conditions similar to those expected to obtain during Cassini's 4-year tour of the saturnian system. Results acquired over a complete range of visual to near-infrared wavelengths from 0.3 to 5.2 μm are presented. First detections include methane fluorescence on Jupiter, a surprisingly high opposition surge on Europa, the first visual-near-IR spectra of Himalia and Jupiter's optically-thin ring system, and the first near-infrared observations of the rings over an extensive range of phase angles (0–120°). Similarities in the center-to-limb profiles of H + 3 and CH 4 emissions indicate that the H + 3 ionospheric density is solar-controlled outside of the auroral regions. The existence of jovian NH 3 absorption at 0.93 μm is confirmed. Himalia has a slightly reddish spectrum, an apparent absorption near 3 μm, and a geometric albedo of 0.06±0.01 at 2.2 μm (assuming an 85-km radius). If the 3-μm feature in Himalia's spectrum is eventually confirmed, it would be suggestive of the presence of water in some form, either free, bound, or incorporated in layer-lattice silicates. Finally, a mean ring-particle radius of 10 μm is found to be consistent with Mie-scattering models fit to VIMS near-infrared observations acquired over 0–120° phase angle.
- Published
- 2003
- Full Text
- View/download PDF
28. Europa : Tidal heating of upwelling thermal plumes and the origin of lenticulae and chaos melting
- Author
-
Sotin, C., Jw., Head, Tobie, G., Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Satellites de Glace ,[SDU]Sciences of the Universe [physics] ,8147 Evolution of the Earth: Planetary interiors (5430 ,Astrophysics::Earth and Planetary Astrophysics ,convection currents and mantle plumes ,8121 Tectonophysics: Dynamics ,8130 Evolution of the Earth: Heat generation and transport ,Physics::Atmospheric and Oceanic Physics ,5724) ,Physics::Geophysics ,6218 Planetology: Solar System Objects: Jovian satellites - Abstract
International audience; Tidal heating models are linked to thermal convection models for ice having strongly temperature dependent viscosity. In the range of ice viscosity inferred from laboratory experiments, tidal forces will heat up rising diapirs on Europa. Partial melt produced in the rising diapirs is predicted to create disruption of near-surface materials and formation of lenticulae and chaos, even if the average ice layer thickness overlying an ocean is larger than 20 km.
- Published
- 2002
- Full Text
- View/download PDF
29. Experiments in the NH3-H2O system in the [0,1 GPa] pressure range - implications for the deep liquid layer of large icy satellites
- Author
-
Mousis, O., Pargamin, J., Grasset, O., Sotin, C., Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
6297 Instruments and techniques. Citation: Mousis ,Satellites de Glace ,J. Pargamin ,[SDU]Sciences of the Universe [physics] ,O. Grasset ,and ,6280 Saturnian satellites ,O ,6218 Planetology: Solar System Objects: Jovian satellites - Abstract
International audience; We have experimentally studied the peritectic's melting temperature of a 25 wt% ammonia water solution in the [0, 1 GPa] pressure range by using a high pressurelow temperature membrane sapphire anvil cell with nitrogen cooled cryostat. Our experimental results are in agreement with those presented by Hogenboom et al. [1997] in the [0, 0.4 GPa] pressure domain where the peritectic's melting temperature follows a plateau at 180 K. The present experimental work fills the lack of data between 0.4 and 0.7 GPa. It also suggests that the peritectic's melting temperature is much higher than that between 0 and 0.4 GPa and does not vary very much with pressure at least up to 1 GPa. This implies the existence of two new high pressure phases in the ammonia-water system. The behaviour of the peritectic's melting curve above 0.5 GPa might play an important role in the evolution of a deep liquid layer in the interiors of the largest icy satellites including Titan, Ganymede and Callisto. We show that the cooling of the deep liquid layer may have involved the crystallization of an ammonia bearing phase at higher temperature than previously expected. If the initial fraction of ammonia relative to ices is greater than 11 weight per cent, taking the partial ammonia depletion into account may lead to a final liquid layer thinner than previously inferred.
- Published
- 2002
- Full Text
- View/download PDF
Catalog
Books, media, physical & digital resources
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.