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196 results on '"Baines K. H."'

151. Interpretation of the 6818.9-A methane feature observed on Jupiter, Saturn, and Uranus

Author

Baines, K. H

Subjects
Lunar And Planetary Exploration
Abstract

High-resolution (0.1-A) spectra of the 6818.9-A methane feature obtained for Jupiter, Saturn, and Uranus by Baines, Schempp, and Smith (1969) are modeled using a doubling and adding code after Hansen (1983). The feature's rotational quantum number is estimated using the relatively homogeneous atmosphere of Saturn, with only J = 0 and J = 1 fitting the observational constraints. The aerosol content within Saturn's northern temperate region is shown to be substantially less than at the equator, indicating a haze only half as optically thick. Models of Jupiter's atmosphere are consistent with the rotational quantum-number assignment. Synthetic line profiles of the 6818.9-A feature observed on Uranus reveal that a substantial haze exists at or above the methane condensation region with an optical depth eight times greater than previously reported. Seasonal effects are indicated. The methane column abundance is 5 + or - 1 km-am. The mixing ratio of methane to hydrogen within the deep unsaturated region of the planet is 0.045 + or - 0.025, based on an H2 column abundance of 240 + or - 60 km-am (Smith, Macy, and Pilcher /1980/), thus indicating that methane comprises between one-sixth and one-half of the planet's mass. However, proper reevaluation of H2 quadrupole features accounting for the haze reported here may significantly reduce the relative methane abundance.

Published
1983
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152. High-resolution observations of the 6815-A band of methane in the major planets

Author

Baines, K. H, Schempp, W. V, and Smith, W. H

Subjects
Astronomy
Abstract

High-resolution (0.1-A) spectra of the 6815-A band of methane are presented for Jupiter, Saturn, Uranus, and Neptune. Spectra for Uranus, Neptune, and the equatorial region of Saturn were acquired with the SPIFI (Smith, Hicks, and Born (1978) at the 2.2-m telescope of the Mauna-Kea Observatory during May and June 1980. Additional spectra were obtained for Jupiter and the northern temperate and polar regions of Saturn in December 1980 and January 1981 from Kitt Peak National Obsevatory's McMath Solar Telescope. The spectra show a dichotomy in strength of methane absorption between Jupiter-Saturn and Uranus-Neptune. A simple model analysis, based on homogeneous scattering models, is unable to resolve whether this dichotomy is due to an actual increase in the methane mixing ratio with solar distance or to the temperature dependence of line strengths and absorption pathlengths in these atmospheres. If the rotational quantum number for the prominent 6818.9-A feature is J less than 4, then significant aerosol extinction must exist within the visibly accessible portion of Uranus' atmosphere for the methane mixing ratio to be greater than the solar value.

Published
1983
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153. Spatially resolved absolute spectrophotometry of Saturn - 3390 to 8080 A

Author

Bergstralh, J. T, Diner, D. J, Baines, K. H, Neff, J. S, Allen, M. A, and Orton, G. S

Subjects
Lunar And Planetary Exploration
Abstract

A series of spatially resolved absolute spectrophotometric measurements of Saturn was conducted for the expressed purpose of calibrating the data obtained with the Imaging Photopolarimeter (IPP) on Pioneer 11 during its recent encounter with Saturn. All observations reported were made at the Mt. Wilson 1.5-m telescope, using a 1-m Ebert-Fastie scanning spectrometer. Spatial resolution was 1.92 arcsec. Photometric errors are considered, taking into account the fixed error, the variable error, and the composite error. The results are compared with earlier observations, as well as with synthetic spectra derived from preliminary physical models, giving attention to the equatorial region and the South Temperate Zone.

Published
1981
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155. TandEM: Titan and Enceladus mission

Author

Coustenis, A., primary, Atreya, S. K., additional, Balint, T., additional, Brown, R. H., additional, Dougherty, M. K., additional, Ferri, F., additional, Fulchignoni, M., additional, Gautier, D., additional, Gowen, R. A., additional, Griffith, C. A., additional, Gurvits, L. I., additional, Jaumann, R., additional, Langevin, Y., additional, Leese, M. R., additional, Lunine, J. I., additional, McKay, C. P., additional, Moussas, X., additional, Müller-Wodarg, I., additional, Neubauer, F., additional, Owen, T. C., additional, Raulin, F., additional, Sittler, E. C., additional, Sohl, F., additional, Sotin, C., additional, Tobie, G., additional, Tokano, T., additional, Turtle, E. P., additional, Wahlund, J.-E., additional, Waite, J. H., additional, Baines, K. H., additional, Blamont, J., additional, Coates, A. J., additional, Dandouras, I., additional, Krimigis, T., additional, Lellouch, E., additional, Lorenz, R. D., additional, Morse, A., additional, Porco, C. C., additional, Hirtzig, M., additional, Saur, J., additional, Spilker, T., additional, Zarnecki, J. C., additional, Choi, E., additional, Achilleos, N., additional, Amils, R., additional, Annan, P., additional, Atkinson, D. H., additional, Bénilan, Y., additional, Bertucci, C., additional, Bézard, B., additional, Bjoraker, G. L., additional, Blanc, M., additional, Boireau, L., additional, Bouman, J., additional, Cabane, M., additional, Capria, M. T., additional, Chassefière, E., additional, Coll, P., additional, Combes, M., additional, Cooper, J. F., additional, Coradini, A., additional, Crary, F., additional, Cravens, T., additional, Daglis, I. A., additional, de Angelis, E., additional, de Bergh, C., additional, de Pater, I., additional, Dunford, C., additional, Durry, G., additional, Dutuit, O., additional, Fairbrother, D., additional, Flasar, F. M., additional, Fortes, A. D., additional, Frampton, R., additional, Fujimoto, M., additional, Galand, M., additional, Grasset, O., additional, Grott, M., additional, Haltigin, T., additional, Herique, A., additional, Hersant, F., additional, Hussmann, H., additional, Ip, W., additional, Johnson, R., additional, Kallio, E., additional, Kempf, S., additional, Knapmeyer, M., additional, Kofman, W., additional, Koop, R., additional, Kostiuk, T., additional, Krupp, N., additional, Küppers, M., additional, Lammer, H., additional, Lara, L.-M., additional, Lavvas, P., additional, Le Mouélic, S., additional, Lebonnois, S., additional, Ledvina, S., additional, Li, J., additional, Livengood, T. A., additional, Lopes, R. M., additional, Lopez-Moreno, J.-J., additional, Luz, D., additional, Mahaffy, P. R., additional, Mall, U., additional, Martinez-Frias, J., additional, Marty, B., additional, McCord, T., additional, Menor Salvan, C., additional, Milillo, A., additional, Mitchell, D. G., additional, Modolo, R., additional, Mousis, O., additional, Nakamura, M., additional, Neish, C. D., additional, Nixon, C. A., additional, Nna Mvondo, D., additional, Orton, G., additional, Paetzold, M., additional, Pitman, J., additional, Pogrebenko, S., additional, Pollard, W., additional, Prieto-Ballesteros, O., additional, Rannou, P., additional, Reh, K., additional, Richter, L., additional, Robb, F. T., additional, Rodrigo, R., additional, Rodriguez, S., additional, Romani, P., additional, Ruiz Bermejo, M., additional, Sarris, E. T., additional, Schenk, P., additional, Schmitt, B., additional, Schmitz, N., additional, Schulze-Makuch, D., additional, Schwingenschuh, K., additional, Selig, A., additional, Sicardy, B., additional, Soderblom, L., additional, Spilker, L. J., additional, Stam, D., additional, Steele, A., additional, Stephan, K., additional, Strobel, D. F., additional, Szego, K., additional, Szopa, C., additional, Thissen, R., additional, Tomasko, M. G., additional, Toublanc, D., additional, Vali, H., additional, Vardavas, I., additional, Vuitton, V., additional, West, R. A., additional, Yelle, R., additional, and Young, E. F., additional

Published
2008
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156. Variable winds on Venus mapped in three dimensions

Author

Sánchez‐Lavega, A., primary, Hueso, R., additional, Piccioni, G., additional, Drossart, P., additional, Peralta, J., additional, Pérez‐Hoyos, S., additional, Wilson, C. F., additional, Taylor, F. W., additional, Baines, K. H., additional, Luz, D., additional, Erard, S., additional, and Lebonnois, S., additional

Published
2008
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157. CHANGING CHARACTERISTICS OF JUPITER'S LITTLE RED SPOT

Author

Cheng, A. F., primary, Simon-Miller, A. A., additional, Weaver, H. A., additional, Baines, K. H., additional, Orton, G. S., additional, Yanamandra-Fisher, P. A., additional, Mousis, O., additional, Pantin, E., additional, Vanzi, L., additional, Fletcher, L. N., additional, Spencer, J. R., additional, Stern, S. A., additional, Clarke, J. T., additional, Mutchler, M. J., additional, and Noll, K. S., additional

Published
2008
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159. Observations in the Saturn system during approach and orbital insertion, with Cassini's visual and infrared mapping spectrometer (VIMS)

Author

Brown, R. H., primary, Baines, K. H., additional, Bellucci, G., additional, Buratti, B. J., additional, Capaccioni, F., additional, Cerroni, P., additional, Clark, R. N., additional, Coradini, A., additional, Cruikshank, D. P., additional, Drossart, P., additional, Formisano, V., additional, Jaumann, R., additional, Langevin, Y., additional, Matson, D. L., additional, McCord, T. B., additional, Mennella, V., additional, Nelson, R. M., additional, Nicholson, P. D., additional, Sicardy, B., additional, Sotin, C., additional, Baugh, N., additional, Griffith, C. A., additional, Hansen, G. B., additional, Hibbitts, C. A., additional, Momary, T. W., additional, and Showalter, M. R., additional

Published
2006
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160. Cassini Visual and Infrared Mapping Spectrometer Observations of Iapetus: Detection of CO 2

Author

Buratti, B. J., primary, Cruikshank, D. P., additional, Brown, R. H., additional, Clark, R. N., additional, Bauer, J. M., additional, Jaumann, R., additional, McCord, T. B., additional, Simonelli, D. P., additional, Hibbitts, C. A., additional, Hansen, G. B., additional, Owen, T. C., additional, Baines, K. H., additional, Bellucci, G., additional, Bibring, J.-P., additional, Capaccioni, F., additional, Cerroni, P., additional, Coradini, A., additional, Drossart, P., additional, Formisano, V., additional, Langevin, Y., additional, Matson, D. L., additional, Mennella, V., additional, Nelson, R. M., additional, Nicholson, P. D., additional, Sicardy, B., additional, Sotin, C., additional, Roush, T. L., additional, Soderlund, K., additional, and Muradyan, A., additional

Published
2005
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161. The Cassini Visual And Infrared Mapping Spectrometer (Vims) Investigation

Author

Brown, R. H., primary, Baines, K. H., additional, Bellucci, G., additional, Bibring, J.-P., additional, Buratti, B. J., additional, Capaccioni, F., additional, Cerroni, P., additional, Clark, R. N., additional, Coradini, A., additional, Cruikshank, D. P., additional, Drossart, P., additional, Formisano, V., additional, Jaumann, R., additional, Langevin, Y., additional, Matson, D. L., additional, Mccord, T. B., additional, Mennella, V., additional, Miller, E., additional, Nelson, R. M., additional, Nicholson, P. D., additional, Sicardy, B., additional, and Sotin, C., additional

Published
2004
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163. Analysis of Jupiter north equatorial belt hot spots in the 4-5 μm range from Galileo/near-infrared mapping spectrometer observations: Measurements of cloud opacity, water, and ammonia

Author

Roos-Serote, M., primary, Drossart, P., additional, Encrenaz, T., additional, Lellouch, E., additional, Carlson, R. W., additional, Baines, K. H., additional, Kamp, L., additional, Mehlman, R., additional, Orton, G. S., additional, Calcutt, S., additional, Irwin, P., additional, Taylor, F., additional, and Weir, A., additional

Published
1998
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164. NEW-FRONTIERS CLASS VENUS IN-SITU EXPLORATION: THE VENUS CLIMATE AND GEOPHYSICS MISSION (VCGM) CONCEPT.

Author

Baines, K. H., Cutts, J. A., Dorsky, L., Hall, J., Akins, A., Davis, A., Komjathy, A., Krishnamoorthy, S., Nikolić, D., Vergados, P., Atreya, S., Bullock, M., Hunter, G., Lebonnois, S., Lognonné, P., Mousis, O., O'Rourke, J., Renard, J.-B., and Wilson, C.

Subjects
GEOPHYSICS, VENUS (Planet), GENERAL circulation model, VENUSIAN atmosphere, INNER planets, ROSSBY waves
Published
2021

168. RADIATIVE TRANSFER MODELLING IN TITAN'S ATMOSPHERE: APPLICATION TO CASSINI/VIMS DATA.

Author

Cornet, T., Rodriguez, S., Maltagliati, L., Appéré, T., Sotin, C., Mouélic, S. Le, Rannou, P., Solomonidou, A., Hirtzig, M., Bézard, B., Coustenis, A., Brown, R. H., Barnes, J. W., Baines, K. H., Buratti, B. J., Clark, R. N., and Nicholson, P. D.

Subjects
SATURN (Planet), TITAN (Satellite), MOLECULAR gas lasers
Published
2017

171. Thermal Evolution of Saturn's 2010-2011 Disturbance

Author

Orton, G. S., Fletcher, L., Yanamandra-Fisher, P., Charlotte Mason, Greco, J., Valkov, S., Baines, K. H., Nanu, R., Villar, G., Trinh, S., Pacheco, J., Sola, M., Momary, T., Greathouse, T. K., Fouchet, T., 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
[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

International audience

172. The Surface Composition of Saturn's Moon Phoebe As seen by the Cassini Visual and Infrared Mapping Spectrometer

Author

Clark, R. N., Brown, R. H., Jaumann, R., Cruikshank, D. P., Nelson, R. M., Buratti, B. J., Mccord, T. B., Hoefen, T. M., Curchin, J. M., Hansen, G., Hibbitts, K., Matz, K. -D, Baines, K. H., Bellucci, G., Bibring, J. -P, Bussoletti, E., Capaccioni, F., Cerroni, P., Coradini, A., Formisano, V., Langevin, Y., Matson, D. L., Vito Mennella, Nicholson, P. D., Sicardy, B., Sotin, C., 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
ComputingMilieux_MISCELLANEOUS
Abstract

International audience

173. Cassini Observations of the Opposition Effect of Saturn's Rings 2. Interpretation: Plaster of Paris as an Analog of Ring Particles

Author

Hapke, B. W., Nelson, R. M., Brown, R. H., Spilker, L. J., Smythe, W. D., Kamp, L., Boryta, M. C., Leader, F., Matson, D. L., Edgington, S., Nicholson, P. D., Filacchione, G., Clark, R. N., Bibring, J. -P, Baines, K. H., Buratti, B. J., Bellucci, G., Capaccioni, F., Cerroni, P., Combes, M., Coradini, A., Cruikshank, D. P., Drossart, P., Formisano, V., Jaumann, R., Langevin, Y., Mccord, T. B., Vito Mennella, Sicardy, B., Sotin, C., 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), 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
Planetengeologie, Saturn, VIMS, Cassini, opposition effect, rings, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

174. Spectral affinities in the icy moons of Saturn investigated through the G-mode multivariate classification method

Author

Tosi, F., Coradini, A., Turrini, D., Capaccioni, F., Cerroni, P., Filacchione, G., Bellucci, G., Brown, R. H., Baines, K. H., Bibring, J., Buratti, B. J., Clark, R. N., Combes, M., Drossart, P., Formisano, V., Jaumann, R., Langevin, Y., Matson, D. L., Mccord, T. B., Vito Mennella, Nelson, R. M., Nicholson, P. D., Sicardy, B., Sotin, C., 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
[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

International audience

175. Surface dissolution on Titan: Ontario Lacus, Sikun Labyrinthus and other karst-like landscapes

Author

Cornet, T., Olivier Bourgeois, Stéphane Le Mouélic, Sotin, C., Cyril Fleurant, Lefevre, A., Rodriguez, S., Malaska, M. J., Barnes, J. W., Brown, R. H., Baines, K. H., Buratti, Bonnie J., Clark, R. N., Nicholson, P. D., Laboratoire de Planétologie et Géodynamique de Nantes ( LPGN ), Université de Nantes ( UN ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ), Littoral, Environnement, Télédétection, Géomatique ( LETG - Angers ), Littoral, Environnement, Télédétection, Géomatique ( LETG ), Université de Caen Normandie ( UNICAEN ), Normandie Université ( NU ) -Normandie Université ( NU ) -Université d'Angers ( UA ) -Université de Nantes ( UN ) -École pratique des hautes études ( EPHE ) -Université de Brest ( UBO ) -Université de Rennes 2 ( UR2 ), Université de Rennes ( UNIV-RENNES ) -Université de Rennes ( UNIV-RENNES ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Caen Normandie ( UNICAEN ), Université de Rennes ( UNIV-RENNES ) -Université de Rennes ( UNIV-RENNES ) -Centre National de la Recherche Scientifique ( CNRS ), Centre d'Etude de Saclay, Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ), Jet Propulsion Laboratory ( JPL ), NASA-California Institute of Technology ( CALTECH ), Department of Physics [Moscow,USA], University of Idaho [Moscow, USA], Lunar and Planetary Laboratory [Tucson], University of Arizona, US Geological Survey [Denver], United States Geological Survey [Reston] ( USGS ), Department of Astronomy [Ithaca], Cornell University, 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), Littoral, Environnement, Télédétection, Géomatique (LETG-Angers), Littoral, Environnement, Télédétection, Géomatique UMR 6554 (LETG), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Université d'Angers (UA)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Brest (UBO)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (IGARUN), Université de Nantes (UN)-Université de Nantes (UN)-Université de Caen Normandie (UNICAEN), Université de Nantes (UN)-Université de Nantes (UN), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Lunar and Planetary Laboratory [Tucson] (LPL), United States Geological Survey [Reston] (USGS), Cornell University [New York], Normandie Université (NU)-Normandie Université (NU)-Université d'Angers (UA)-École Pratique des Hautes Études (EPHE), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Brest (UBO)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (IGARUN)

Subjects
[ SDE.MCG ] Environmental Sciences/Global Changes, [SDE.MCG]Environmental Sciences/Global Changes, [SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology, [ SDU.STU.HY ] Sciences of the Universe [physics]/Earth Sciences/Hydrology, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

176. Missions to Venus

Author

Titov, D. V., Baines, K. H., Basilevsky, A. T., Chassefiere, E., Chin, G., Crisp, D., Esposito, L. W., Lebreton, J. -P, Lellouch, E., Moroz, V. I., Nagy, A. F., Owen, T. C., Oyama, K. -I, Russell, C. T., Fred Taylor, and Young, R. E.

177. Cassini Observations of the Opposition Effect of Saturn's Rings-1

Author

Nelson, R. M., Hapke, B. W., Brown, R. H., Spilker, L. J., Smythe, W. D., Kamp, L., Boryta, M. C., Leader, F., Matson, D. L., Edgington, S., Nicholson, P. D., Filacchione, G., Clark, R. N., Bibring, J. -P, Baines, K. H., Buratti, B. J., Bellucci, G., Capaccioni, F., Cerroni, P., Combes, M., Coradini, A., Cruikshank, D. P., Drossart, P., Formisano, V., Jaumann, R., Langevin, Y., Mccord, T. B., Vito Mennella, Sicardy, B., Sotin, C., 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), 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
[SDU]Sciences of the Universe [physics], [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

178. Saturn's Titan: Evidence for Surface Reflectance Change: Implications for Atmospheric and Volcanic Activity

Author

Nelson, R. M., Kamp, L., Matson, D. L., Irwin, P. G., Baines, K. H., Boryta, M. D., Leader, F. E., Jaumann, R., Smythe, W. D., Sotin, C., Clark, R. N., Cruikshank, D. P., Drossart, P., Pearl, J. C., Hapke, B. W., Lunine, J., Combes, M., Bellucci, G., Biebring, J., Capaccioni, F., Cerroni, P., Coradini, A., Formisano, V., Filacchione, G., Langevin, Y., Mccord, T. B., Vito Mennella, Nicholson, P. D., Sicardy, B., 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
[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

International audience

179. Saturn's Titan: Searching for Surface Change

Author

Nelson, R. M., Kamp, L., Matson, D. L., Boryta, M. D., Leader, F., Baines, K. H., Lopes, R., Smythe, W. D., Jauman, R., Sotin, C., Clark, R. N., Cruikshank, D. P., Drosart, P., Hapke, B. W., Buratti, B. J., Brown, R. H., Sicardy, B., Lunine, J. I., Combes, M., Belucci, G., Biebring, J., Capaccioni, M., Cerroni, P., Corodini, A., Formisano, V., Filacchione, G., Langevin, Y., Mccord, T., Vito Mennella, Nicholson, P., 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
[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

International audience

180. Aromatic Hydrocarbons on Iapetus and Phoebe: Cassini-VIMS Detections

Author

Cruikshank, D. P., Wegryn, E., Dalle Ore, C. M., Baines, K. H., Buratti, B. J., Matson, D. L., Nelson, R. M., Bellucci, G., Capaccioni, F., Cerroni, P., Coradini, A., Formisano, V., Vito Mennella, Bibring, J. -P, Langevin, Y., Brown, R. H., Clark, R. N., Combes, M., Drossart, P., Sicardy, B., Jaumann, R., Mccord, T. B., Nicholson, P. D., 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), 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
[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

184. Simultaneous Cassini VIMS and UVIS observations of Saturn's southern aurora: Comparing emissions from H, H2and H3+at a high spatial resolution

Author

Melin, H., Stallard, T., Miller, S., Gustin, J., Galand, M., Badman, S. V., Pryor, W. R., O'Donoghue, J., Brown, R. H., and Baines, K. H.

Abstract

Here, for the first time, temporally coincident and spatially overlapping Cassini VIMS and UVIS observations of Saturn's southern aurora are presented. Ultraviolet auroral H and H2emissions from UVIS are compared to infrared H3+emission from VIMS. The auroral emission is structured into three arcs – H, H2and H3+are morphologically identical in the bright main auroral oval (∼73°S), but there is an equatorward arc that is seen predominantly in H (∼70°S), and a poleward arc (∼74°S) that is seen mainly in H2and H3+. These observations indicate that, for the main auroral oval, UV emission is a good proxy for the infrared H3+morphology (and vice versa), but for emission either poleward or equatorward this is no longer true. Hence, simultaneous UV/IR observations are crucial for completing the picture of how the atmosphere interacts with the magnetosphere. Main auroral oval is morphologically very similar in the UV as the IREquatorward and poleward of the main oval there are strong UV/IR differencesProof of concept for simultaneous VIMS/UVIS observations

Published
2011
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187. The Unusual Dynamics of Northern Dark Spots on Neptune

Author

Sromovsky, L. A., Fry, P. M., and Baines, K. H.

Subjects
*NEPTUNE (Planet), *PLANETARY atmospheres
Abstract

Hubble Space Telescope (HST) and ground-based observations of Neptune from 1991 to 2000 show that Neptune''s northern Great Dark Spots (NGDS) remained remarkably stable in latitude and longitudinal drift rate, in marked contrast to the 1989 southern Great Dark Spot (GDS), which moved continuously equatorward during 1989 and dissipated unseen during 1990. NGDS-32, discovered in October 1994 HST images, (H. B. Hammel et al., 1995, Science268, 1740–1742), stayed at ∼32°N from 1994 through at least 1996, and possibly through 2000. The second northern GDS (NGDS-15), discovered in August 1996 HST images, (L. A. Sromovsky et al. 2001, Icarus146, 459–488), appears to have existed as early as 8 March 1996 and remained near 15°N for the 16 months over which it was observed. NGDS-32 had a very uniform longitudinal drift rate averaging −36.28±0.04°/day from 10 October 1994 to 2 November 1995, and −35.84±0.02°/day from 1 September 1995 through 24 November 1995. A single circulation feature certainly exists during each of the first two periods, though it is not certain that it is the same feature. It is probable, but less certain, that only a single circulation feature was tracked during the 1996–1998 period, during which positions are consistent with a modulated drift rate averaging −35.401±0.001°/day, but with a peak-to-peak modulation of 1.5°/day with an ∼760-day period. If NDS-32 varied its drift rate in accord with the local latitudinal shear in the zonal wind, then all its drift-rate changes might be due to only ∼0.4° of latitudinal motion. The movement of NGDS-15 is also not consistent with a uniform longitudinal drift rate, but the nature of its variation cannot be estimated from the limited set of observations. The relatively stable latitudinal positions of both northern dark spots are not consistent with current numerical model calculations treating them as anticyclonic vortices in a region of uniform potential vorticity gradient (R. P. Lebeau and T. E. Dowling 1998, Icarus132, 239–265). Possible explanations include unresolved latitudinal structure in the zonal wind background or unaccounted-for variations in vertical stability structure. [Copyright &y& Elsevier]

Published
2002
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188. High-Resolution Infrared Imaging of Neptune from the Keck Telescope

Author

Gibbard, S. G., Roe, H., de Pater, I., Macintosh, B., Gavel, D., Max, C. E., Baines, K. H., and Ghez, A.

Subjects
*NEPTUNE (Planet), *INFRARED imaging, *SPECKLE interference
Abstract

We present results of infrared observations of Neptune from the 10-m W. M. Keck I Telescope, using both high-resolution (0.04 arcsecond) broadband speckle imaging and conventional imaging with narrowband filters (0.6 arcsec resolution). The speckle data enable us to track the size and shape of infrared-bright features (“storms”) as they move across the disk and to determine rotation periods for latitudes −30 and −45°. The narrowband data are input to a model that allows us to make estimates of Neptune''s stratospheric haze abundance and the size of storm features. We find a haze column density of ∼106 cm−2 for a haze layer located in the stratosphere, and a lower limit of 107 cm−2 and an upper limit of 109 cm−2 for a layer of 0.2 μm particles in the troposphere. We also calculate a lower limit of 7×106 km2 for the size of a “storm” feature observed on 13 October 1997. [Copyright &y& Elsevier]

Published
2002
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189. Release of volatiles from a possible cryovolcano from near-infrared imaging of Titan.

Author

Sotin C, Jaumann R, Buratti BJ, Brown RH, Clark RN, Soderblom LA, Baines KH, Bellucci G, Bibring JP, Capaccioni F, Cerroni P, Combes M, Coradini A, Cruikshank DP, Drossart P, Formisano V, Langevin Y, Matson DL, McCord TB, Nelson RM, Nicholson PD, Sicardy B, LeMouelic S, Rodriguez S, Stephan K, and Scholz CK

Subjects
Atmosphere chemistry, Gases chemistry, Geography, Hydrocarbons analysis, Hydrocarbons chemistry, Methane analysis, Methane chemistry, Spacecraft, Extraterrestrial Environment chemistry, Gases analysis, Ice analysis, Infrared Rays, Moon, Photography, Saturn
Abstract

Titan is the only satellite in our Solar System with a dense atmosphere. The surface pressure is 1.5 bar (ref. 1) and, similar to the Earth, N2 is the main component of the atmosphere. Methane is the second most important component, but it is photodissociated on a timescale of 10(7) years (ref. 3). This short timescale has led to the suggestion that Titan may possess a surface or subsurface reservoir of hydrocarbons to replenish the atmosphere. Here we report near-infrared images of Titan obtained on 26 October 2004 by the Cassini spacecraft. The images show that a widespread methane ocean does not exist; subtle albedo variations instead suggest topographical variations, as would be expected for a more solid (perhaps icy) surface. We also find a circular structure approximately 30 km in diameter that does not resemble any features seen on other icy satellites. We propose that the structure is a dome formed by upwelling icy plumes that release methane into Titan's atmosphere.

Published
2005
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190. Compositional maps of Saturn's moon Phoebe from imaging spectroscopy.

Author

Clark RN, Brown RH, Jaumann R, Cruikshank DP, Nelson RM, Buratti BJ, McCord TB, Lunine J, Baines KH, Bellucci G, Bibring JP, Capaccioni F, Cerroni P, Coradini A, Formisano V, Langevin Y, Matson DL, Mennella V, Nicholson PD, Sicardy B, Sotin C, Hoefen TM, Curchin JM, Hansen G, Hibbits K, and Matz KD

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
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191. Energy, volatile production, and climatic effects of the Chicxulub Cretaceous/Tertiary impact.

Author

Pope KO, Baines KH, Ocampo AC, and Ivanov BA

Subjects
Acid Rain, Atmosphere analysis, Biological Evolution, Carbon Dioxide chemistry, Carbonates analysis, Climate, Geologic Sediments analysis, Geological Phenomena, Geology, Greenhouse Effect, Mexico, Paleontology, Sulfur Dioxide chemistry, Sulfuric Acids chemistry, Volatilization, Aerosols chemistry, Atmosphere chemistry, Evolution, Planetary, Meteoroids, Minor Planets, Models, Chemical, Seawater chemistry
Abstract

A comprehensive analysis of volatiles in the Chicxulub impact strongly supports the hypothesis that impact-generated sulfate aerosols caused over a decade of global cooling, acid rain, and disruption of ocean circulation, which contributed to the mass extinction at the Cretaceous/Tertiary (K/T) boundary. The crater size, meteoritic content of the K/T boundary clay, and impact models indicate that the Chicxulub crater was formed by a short period comet or an asteroid impact that released 0.7-3.4 x 10(31) ergs of energy. Impact models and experiments combined with estimates of volatiles in the projectile and target rocks predict that over 200 gigatons (Gt) each of SO2 and water vapor, and over 500 Gt of CO2, were globally distributed in the stratosphere by the impact. Additional volatiles may have been produced on a global or regional scale that formed sulfate aerosols rapidly in cooler parts of the vapor plume, causing an early, intense pulse of sulfuric acid rain. Estimates of the conversion rate of stratospheric SO2 and water vapor to sulfate aerosol, based on volcanic production of sulfate aerosols, coupled with calculations of diffusion, coagulation, and sedimentation, demonstrate that the 200 Gt stratospheric SO2 and water vapor reservoir would produce sulfate aerosols for 12 years. These sulfate aerosols caused a second pulse of acid rain that was global. Radiative transfer modeling of the aerosol clouds demonstrates (1) that if the initial rapid pulse of sulfate aerosols was global, photosynthesis may have been shut down for 6 months and (2) that for the second prolonged aerosol cloud, solar transmission dropped 80% by the end of first year and remained 50% below normal for 9 years. As a result, global average surface temperatures probably dropped between 5 degrees and 31 degrees K, suggesting that global near-freezing conditions may have been reached. Impact-generated CO2 caused less than 1 degree K greenhouse warming and therefore was insignificant compare to the sulfate cooling. The magnitude of sulfate cooling depends largely upon the rate of ocean mixing as surface waters cool, sink, and are replaced by upwelling of deep ocean water. This upwelling apparently drastically altered ocean stratification and circulation, which may explain the global collapse of the delta 13C gradient between surface and deep ocean waters at the K/T boundary.

Published
1997
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192. Impact debris particles in Jupiter's stratosphere.

Author

West RA, Karkoschka E, Friedson AJ, Seymour M, Baines KH, and Hammel HB

Subjects
Atmosphere, Nitrogen analysis, Sulfur analysis, Temperature, Extraterrestrial Environment, Jupiter, Solar System
Abstract

The aftermath of the impacts of periodic comet Shoemaker-Levy 9 on Jupiter was studied with the Wide Field Planetary Camera 2 on the Hubble Space Telescope. The impact debris particles may owe their dark brown color to organic material rich in sulfur and nitrogen. The total volume of aerosol 1 day after the last impact is equal to the volume of a sphere of radius 0.5 kilometer. In the optically thick core regions, the particle mean radius is between 0.15 and 0.3 micrometer, and the aerosol is spread over many scale heights, from approximately 1 millibar to 200 millibars of pressure or more. Particle coagulation can account for the evolution of particle radius and total optical depth during the month following the impacts.

Published
1995
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193. Spatial Organization and Time Dependence of Jupiter's Tropospheric Temperatures, 1980-1993.

Author

Orton GS, Friedson AJ, Yanamandra-Fisher PA, Caldwell J, Hammel HB, Baines KH, Bergstralh JT, Martin TZ, West RA, Veeder GJ Jr, Lynch DK, Russell R, Malcom ME, Golisch WF, Griep DM, Kaminski CD, Tokunaga AT, Herbst T, and Shure M

Abstract

The spatial organization and time dependence of Jupiter's temperatures near 250-millibar pressure were measured through a jovian year by imaging thermal emission at 18 micrometers. The temperature field is influenced by seasonal radiative forcing, and its banded organization is closely correlated with the visible cloud field. Evidence was found for a quasi-periodic oscillation of temperatures in the Equatorial Zone, a correlation between tropospheric and stratospheric waves in the North Equatorial Belt, and slowly moving thermal features in the North and South Equatorial Belts. There appears to be no common relation between temporal changes of temperature and changes in the visual albedo of the various axisymmetric bands.

Published
1994
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194. Clouds, hazes, and the stratospheric methane abundance in Neptune.

Author

Baines KH and Hammel HB

Subjects
Astronomical Phenomena, Astronomy, Atmosphere analysis, Hydrocarbons analysis, Models, Chemical, Aerosols analysis, Atmosphere chemistry, Extraterrestrial Environment, Methane analysis, Neptune
Abstract

Analysis of high-spatial-resolution (approximately 0.8 arcsec) methane band and continuum imagery of Neptune's relatively homogeneous Equatorial Region yields significant constraints on (1) the stratospheric gaseous methane mixing ratio (fCH4,s), (2) the column abundances and optical properties of stratospheric and tropospheric hydrocarbon hazes, and (3) the wavelength-dependent single-scattering albedo of the 3-bar opaque cloud. From the center-to-limb behavior of the 7270-angstroms and 8900-angstrom sCH4 bands, the stratospheric methane mixing ratio is limited to fCH4,s < 1.7 x 10(-3), with a nominal value of fCH4,s = 3.5 x 10(-4), one to two orders of magnitude less than pre-Voyager estimates, but in agreement with a number of recent ultraviolet and thermal infrared measurements, and largely in agreement with the tropopause mixing ratio implied by Voyager temperature measurements. Upper limits to the stratospheric haze mass column abundance and 6190-angstroms and 8900-angstroms haze opacities are 0.61 microgram cm-2 and 0.075 and 0.042, respectively, with nominal values of 0.20 microgram cm-2 and 0.025 and 0.014 for the 0.2-micrometer radius particles preferred by the recent Voyager PPS analysis of Pryor et al. (1992, Icarus 99, 302-316). The tropospheric CH4 haze opacities are comparable to that found in the stratosphere, upper limits of 0.104 and 0.065 at 6190 angstroms and 8900 angstroms, respectively, with nominal values of 0.085 and 0.058. This indicates a column abundance less than 11.0 micrograms cm-2, corresponding to the methane gas content within a well-mixed 3% methane tropospheric layer only 0.1 cm thick near the 1.5-bar CH4 condensation level. Constraints on the single-scattering albedos of these hazes include (1) for the stratospheric component, 6190-angstroms and 8900-angstroms imaginary indices of refraction less than 0.047 and 0.099, respectively, with 0.000 (conservative scattering) being the nominal value at both wavelengths, and (2) CH4 haze single-scattering albedos greater than 0.85 and 0.50 at these two wavelengths, with conservative scattering again begin the preferred value. However, conservative scattering is ruled out for the opaque cloud near 3 bars marking the bottom of the visible atmosphere. Specifically, we find cloud single-scattering albedos of 0.915 +/- 0.006 at 6340 angstroms, 0.775 +/- 0.012 at 7490 angstroms, and 0.803 +/- 0.010 at 8260 angstrom. Global models utilizing a complete global spectrum confirm the red-absorbing character of the 3-bar cloud. The global-mean model has approximately 7.7 times greater stratospheric aerosol content then the Equatorial Region. An analysis of stratospheric haze precipitation rates indicates a steady-state haze production rate of 0.185-1.5 x 10(-14) g cm-2 sec-1, in agreement with recent theoretical photochemical estimates. Finally, reanalysis of the Voyager PPS 7500-angstroms phase angle data utilizing the fCH4,s value derived here confirms the Pryor et al. result of a tropospheric CH4 haze opacity of a few tenths in the 22-30 degrees S latitude region, several times that of the Equatorial Region or of the globe. The factor-of-10 reduction in fCH4,s below that assumed by Pryor et al. implies decreased gas absorption and consequently a decrease in the forward-scattering component of tropospheric aerosols.

Published
1994
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195. Galileo infrared imaging spectroscopy measurements at venus.

Author

Carlson RW, Baines KH, Encrenaz T, Taylor FW, Drossart P, Kamp LW, Pollack JB, Lellouch E, Collard AD, Calcutt SB, Grinspoon D, Weissman PR, Smythe WD, Ocampo AC, Danielson GE, Fanale FP, Johnson TV, Kieffer HH, Matson DL, McCord TB, and Soderblom LA

Abstract

During the 1990 Galileo Venus flyby, the Near Infaied Mapping Spectrometer investigated the night-side atmosphere of Venus in the spectral range 0.7 to 5.2 micrometers. Multispectral images at high spatial resolution indicate substanmial cloud opacity variations in the lower cloud levels, centered at 50 kilometers altitude. Zonal and meridional winds were derived for this level and are consistent with motion of the upper branch of a Hadley cell. Northern and southern hemisphere clouds appear to be markedly different. Spectral profiles were used to derive lower atmosphere abundances of water vapor and other species.

Published
1991
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196. Thermal maps of jupiter: spatial organization and time dependence of stratospheric temperatures, 1980 to 1990.

Author

Orton GS, Friedson AJ, Baines KH, Martin TZ, West RA, Caldwell J, Hammel HB, Bergstralh JT, Malcom ME, Golisch WF, Griep DM, Kaminski CD, Tokunaga AT, Baron R, and Shure M

Abstract

The spatial organization and time dependence of Jupiter's stratospheric temperatures have been measured by observing thermal emission from the 7.8-micrometer CH(4) band. These temperatures, observed through the greater part of a Jovian year, exhibit the influence of seasonal radiative forcing. Distinct bands of high temperature are located at the poles and mid-latitudes, while the equator alternates between warm and cold with a period of approximately 4 years. Substantial longitudinal variability is often observed within the warm mid-latitude bands, and occasionally elsewhere on the planet. This variability includes small, localized structures, as well as large-scale waves with wavelengths longer than approximately 30,000 kilometers. The amplitudes of the waves vary on a time scale of approximately 1 month; structures on a smaller scale may have lifetimes of only days. Waves observed in 1985, 1987, and 1988 propagated with group velocities less than +/-30 meters per second.

Published
1991
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