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2. TandEM: Titan and Enceladus mission

Author

J. E. Blamont, Tobias Owen, Michael Küppers, Xenophon Moussas, Robert H. Brown, Nicole Schmitz, Sascha Kempf, C. Menor Salvan, T. W. Haltigin, Olivier Grasset, Roger V. Yelle, Wayne H. Pollard, Daniel Gautier, Paul R. Mahaffy, Joe Pitman, Iannis Dandouras, Daphne Stam, John C. Zarnecki, Bruno Sicardy, Georges Durry, Jesús Martínez-Frías, Norbert Krupp, S. Le Mouélic, Matthias Grott, Sébastien Lebonnois, T. Krimigis, Elizabeth P. Turtle, Alain Herique, Linda Spilker, Ralph D. Lorenz, Maria Teresa Capria, M. Combes, John F. Cooper, O. Mousis, Joachim Saur, Wlodek Kofman, J. Bouman, M. Paetzold, Hojatollah Vali, C. Dunford, Sushil K. Atreya, Eric Chassefière, I. de Pater, T. B. McCord, Bruno Bézard, Gabriel Tobie, Catherine D. Neish, M. Ruiz Bermejo, Sergei Pogrebenko, Kim Reh, Athena Coustenis, Ralf Jaumann, Angioletta Coradini, Leonid I. Gurvits, Andrew J. Coates, Tibor S. Balint, H. Hussmann, E. Choi, Ioannis A. Daglis, Edward C. Sittler, Emmanuel Lellouch, Robert A. West, L. Boireau, E.F. Young, Timothy A. Livengood, Cesar Bertucci, Martin G. Tomasko, M. Fujimoto, Ingo Müller-Wodarg, Yves Bénilan, Wing-Huen Ip, Marina Galand, Darrell F. Strobel, Cyril Szopa, Pascal Rannou, D. G. Mitchell, Mark Leese, Véronique Vuitton, P. Annan, Tetsuya Tokano, Caitlin A. Griffith, Conor A. Nixon, Stephen A. Ledvina, Karoly Szego, Andrew Morse, Panayotis Lavvas, Luisa Lara, C. de Bergh, Jonathan I. Lunine, R. A. Gowen, Katrin Stephan, Jianping Li, Glenn S. Orton, Michel Blanc, Esa Kallio, Ronan Modolo, M. Hirtzig, Helmut Lammer, Nicholas Achilleos, D. Nna Mvondo, Frank Sohl, M. Nakamura, Andrew Steele, C. C. Porco, Marcello Fulchignoni, Gordon L. Bjoraker, Olga Prieto-Ballesteros, J. J. López-Moreno, Andrew Dominic Fortes, Rafael Rodrigo, Patrice Coll, Francesca Ferri, François Raulin, Tom Spilker, F. J. Crary, J. H. Waite, Dirk Schulze-Makuch, Thomas E. Cravens, Kevin H. Baines, C. P. McKay, L. Richter, D. Luz, David H. Atkinson, Martin Knapmeyer, Robert E. Johnson, D. Fairbrother, F. M. Flasar, Roland Thissen, Paul N. Romani, Sebastien Rodriguez, Urs Mall, Paul M. Schenk, Franck Hersant, R. Koop, Odile Dutuit, I. Vardavas, T. Kostiuk, Ricardo Amils, Konrad Schwingenschuh, Robert V. Frampton, Fritz M. Neubauer, Jan-Erik Wahlund, L. A. Soderblom, Michele K. Dougherty, Anna Milillo, Frank T. Robb, Bernard Schmitt, Christophe Sotin, Michel Cabane, A. Selig, Bernard Marty, Yves Langevin, Rosaly M. C. Lopes, Emmanuel T. Sarris, E. De Angelis, D. Toublanc, 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), Department of Atmospheric, Oceanic, and Space Sciences [Ann Arbor] (AOSS), University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Lunar and Planetary Laboratory [Tucson] (LPL), University of Arizona, Space and Atmospheric Physics Group [London], Blackett Laboratory, Imperial College London-Imperial College London, Centro di Ateneo di Studi e Attività Spaziali 'Giuseppe Colombo' (CISAS), Università degli Studi di Padova = University of Padua (Unipd), Mullard Space Science Laboratory (MSSL), University College of London [London] (UCL), Joint Institute for VLBI in Europe (JIVE ERIC), Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), The Open University [Milton Keynes] (OU), NASA Ames Research Center (ARC), Department of Physics [Athens], National and Kapodistrian University of Athens (NKUA), University of Cologne, Institute for Astronomy [Honolulu], University of Hawai‘i [Mānoa] (UHM), Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), NASA Goddard Space Flight Center (GSFC), 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), Johns Hopkins University Applied Physics Laboratory [Laurel, MD] (APL), Swedish Institute of Space Physics [Uppsala] (IRF), Space Science Division [San Antonio], Southwest Research Institute [San Antonio] (SwRI), Centre National d'Études Spatiales [Toulouse] (CNES), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Academy of Athens, Observatoire de Paris - Site de Paris (OP), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Space Science Institute [Boulder] (SSI), Bombardier Aerospace, Centro de Astrobiologia [Madrid] (CAB), Instituto Nacional de Técnica Aeroespacial (INTA)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Sensors and Software, University of Idaho [Moscow, USA], SRON Netherlands Institute for Space Research (SRON), PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Istituto Nazionale di Astrofisica (INAF), University of Kansas [Lawrence] (KU), National Observatory of Athens (NOA), Department of Astronomy [Berkeley], University of California [Berkeley] (UC Berkeley), University of California (UC)-University of California (UC), Service d'aéronomie (SA), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Planétologie de Grenoble (LPG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency [Sagamihara] (JAXA), McGill University = Université McGill [Montréal, Canada], FORMATION STELLAIRE 2009, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB), Institute of Astronomy [Taiwan] (IANCU), National Central University [Taiwan] (NCU), University of Virginia [Charlottesville], Finnish Meteorological Institute (FMI), Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, DLR Institut für Planetenforschung, Deutsches Zentrum für Luft- und Raumfahrt [Berlin] (DLR), Space Research Institute of Austrian Academy of Sciences (IWF), Austrian Academy of Sciences (OeAW), Instituto de Astrofísica de Andalucía (IAA), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG), Institute of Atmospheric Physics [Beijing] (IAP), Chinese Academy of Sciences [Beijing] (CAS)-Chinese Academy of Sciences [Beijing] (CAS), National Center for Earth and Space Science Education (NCESSE), Observatório Astronómico de Lisboa, Centre de Recherches Pétrographiques et Géochimiques (CRPG), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Bear Fight Center, Univers, Transport, Interfaces, Nanostructures, Atmosphère et environnement, Molécules (UMR 6213) (UTINAM), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Lockheed Martin Space, Groupe de spectrométrie moléculaire et atmosphérique (GSMA), Université de Reims Champagne-Ardenne (URCA)-Centre National de la Recherche Scientifique (CNRS), University of Maryland Biotechnology Institute Baltimore, University of Maryland [Baltimore], Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Democritus University of Thrace (DUTH), Lunar and Planetary Institute [Houston] (LPI), School of Earth and Environmental Sciences [Pullman], Washington State University (WSU), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Universita degli Studi di Padova, National and Kapodistrian University of Athens = University of Athens (NKUA | UoA), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Planétologie et Géodynamique UMR6112 (LPG), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Nantes - Faculté des Sciences et des Techniques, Université de Nantes (UN)-Université de Nantes (UN)-Université d'Angers (UA), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS), Instituto Nacional de Técnica Aeroespacial (INTA)-Consejo Superior de Investigaciones Científicas [Spain] (CSIC), IMPEC - LATMOS, University of California [Berkeley], University of California-University of California, Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), McGill University, École normale supérieure - Paris (ENS Paris)-École normale supérieure - Paris (ENS Paris), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Université de Franche-Comté (UFC)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), University of Virginia, Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS), Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École des Ponts ParisTech (ENPC)-École polytechnique (X)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)

Subjects
Exploration of Saturn, Solar System, Cosmic Vision, 010504 meteorology & atmospheric sciences, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Computer science, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], TandEM, 01 natural sciences, law.invention, Astrobiology, Enceladus, Orbiter, symbols.namesake, law, Saturnian system, 0103 physical sciences, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Spacecraft, Tandem, business.industry, Astronomy and Astrophysics, Landing probes, Space and Planetary Science, symbols, Titan, business, Titan (rocket family)
Abstract

著者人数：156名, Accepted: 2008-05-27, 資料番号: SA1000998000

Published
2009
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3. Possible tropical lakes on Titan from observations of dark terrain

Author

Martin G. Tomasko, Juan M. Lora, Paulo Penteado, Charles See, Jake D. Turner, Robert H. Brown, Lyn R. Doose, and Caitlin A. Griffith

Subjects
Multidisciplinary, Atmospheric sciences, Arid, Methane, Latitude, chemistry.chemical_compound, symbols.namesake, chemistry, Radiative transfer, symbols, Environmental science, Atmosphere of Titan, Water cycle, Titan (rocket family), Surface water
Abstract

Low-latitude near-infrared spectral images of Titan reveal what are probably dark liquid lakes of methane. Saturn's moon Titan has a 'methane cycle' that is similar, in principle, to Earth's water cycle, although surface liquid seems relatively scarce on Titan, being detected mainly at high latitudes. The fact that Titan can supply its atmosphere with methane — together with signs of surface water erosion around the Huygens probe landing site in what seems to be an otherwise arid region of the tropics — suggests that there may be more surface liquid to be discovered. This paper reports near-infrared spectral images of an area in the tropics that reveal a dark region, which could indicate the presence of liquid methane on the moon's surface, supplied by subterranean sources. Titan has clouds, rain and lakes—like Earth—but composed of methane rather than water. Unlike Earth, most of the condensable methane (the equivalent of 5 m depth globally averaged1) lies in the atmosphere. Liquid detected on the surface (about 2 m deep) has been found by radar images only poleward of 50° latitude2,3, while dune fields pervade the tropics4. General circulation models explain this dichotomy, predicting that methane efficiently migrates to the poles from these lower latitudes5,6,7. Here we report an analysis of near-infrared spectral images8 of the region between 20° N and 20° S latitude. The data reveal that the lowest fluxes in seven wavelength bands that probe Titan's surface occur in an oval region of about 60 × 40 km2, which has been observed repeatedly since 2004. Radiative transfer analyses demonstrate that the resulting spectrum is consistent with a black surface, indicative of liquid methane on the surface. Enduring low-latitude lakes are best explained as supplied by subterranean sources (within the last 10,000 years), which may be responsible for Titan’s methane, the continual photochemical depletion of which furnishes Titan's organic chemistry9.

Published
2012
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4. Measurements of the atmospheric water vapor on Mars by the Imager for Mars Pathfinder

Author

Pete Smith, Mark T. Lemmon, Martin G. Tomasko, D. V. Titov, Nicolas Thomas, R. M. Sablotny, H. U. Keller, and W. J. Markiewicz

Subjects
Atmospheric Science, Ecology, Continuum (design consultancy), Elevation, Paleontology, Soil Science, Forestry, Mars Exploration Program, Atmosphere of Mars, Aquatic Science, Oceanography, Atmospheric sciences, Atmosphere, Geophysics, Space and Planetary Science, Geochemistry and Petrology, Earth and Planetary Sciences (miscellaneous), Transmittance, Absorption (electromagnetic radiation), Geology, Water vapor, Earth-Surface Processes, Water Science and Technology
Abstract

The Imager for Mars Pathfinder (IMP) was the first instrument to measure the atmospheric water on Mars from its surface. It took the images of the Sun through the Martian atmosphere in five narrowband filters, two in the 0.94 μm H2O band and three in the continuum around it. The observations were carried out in the mornings and in the evenings when the Sun was between 3° and 8° above the horizon. The absorption due to the atmospheric water vapor did not exceed 2%. An average column density of 6±4 precipitated microns (pr μm) was derived from the IMP data. The dependence of the observed H2O transmittance on Sun elevation tentatively implies that the water vapor is not uniformly mixed in the atmosphere but is rather confined to a layer 1–3 km thick near the surface. IMP observations also indicate a horizontal inhomogeneity of the layer but show no significant morning-to-evening variations of the water vapor amount.

Published
1999
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5. Results from the Mars Pathfinder Camera

Author

Mark T. Lemmon, R. M. Sablotny, James F. Bell, E. Wegryn, T. J. Parker, Jeffrey R. Johnson, Peter H. Smith, Michael C. Malin, Scott L. Murchie, R. L. Kirk, Martin G. Tomasko, Carol R. Stoker, Ralf Jaumann, H. U. Keller, L. A. Soderblom, Ryan C. Sullivan, N. Thomas, Justin N. Maki, R. J. Reid, W. Ward, Kenneth E. Herkenhoff, Juergen Oberst, Daniel T. Britt, Ronald Greeley, Lisa R. Gaddis, and Nathan T. Bridges

Subjects
Minerals, Multidisciplinary, Haze, Spectral signature, Extraterrestrial Environment, Atmosphere, Ice, Mars, Water, Mineralogy, Wind, Mars Exploration Program, Impactite, Martian surface, Aeolian processes, Geology, Water vapor
Abstract

Images of the martian surface returned by the Imager for Mars Pathfinder (IMP) show a complex surface of ridges and troughs covered by rocks that have been transported and modified by fluvial, aeolian, and impact processes. Analysis of the spectral signatures in the scene (at 440- to 1000-nanometer wavelength) reveal three types of rock and four classes of soil. Upward-looking IMP images of the predawn sky show thin, bluish clouds that probably represent water ice forming on local atmospheric haze (opacity ∼0.5). Haze particles are about 1 micrometer in radius and the water vapor column abundance is about 10 precipitable micrometers.

Published
1997
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6. Solar and Thermal Radiation in Jupiter's Atmosphere: Initial Results of the Galileo Probe Net Flux Radiometer

Author

A. D. Collard, Patrick M. Fry, Martin G. Tomasko, J. L. Hayden, Fred A. Best, Glenn S. Orton, Henry E. Revercomb, R. S. Freedman, Lawrence A. Sromovsky, and Mark T. Lemmon

Subjects
Sunlight, Physics, Multidisciplinary, Radiometer, Extraterrestrial Environment, Atmosphere, Temperature, Galileo Probe, Water, Atmospheric sciences, Oxygen, Jupiter, Ammonia, Thermal radiation, Thermal, Pressure, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Radiometry, Physics::Atmospheric and Oceanic Physics, Astrophysics::Galaxy Astrophysics, Water vapor
Abstract

The Galileo probe net flux radiometer measured radiation within Jupiter's atmosphere over the 125-kilometer altitude range between pressures of 0.44 bar and 14 bars. Evidence for the expected ammonia cloud was seen in solar and thermal channels down to 0.5 to 0.6 bar. Between 0.6 and 10 bars large thermal fluxes imply very low gaseous opacities and provide no evidence for a deep water cloud. Near 8 bars the water vapor abundance appears to be about 10 percent of what would be expected for a solar abundance of oxygen. Below 8 bars, measurements suggest an increasing water abundance with depth or a deep cloud layer. Ammonia appears to follow a significantly subsaturated profile above 3 bars. Unexpectedly high absorption of sunlight was found at wavelengths greater than 600 nanometers.

Published
1996
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7. Topography and geomorphology of the Huygens landing site on Titan

Author

Mark R. Rosiek, Michael W. Bushroe, Charles See, Brent A. Archinal, Bonnie L. Redding, Laurence A. Soderblom, Martin G. Tomasko, Jonathan I. Lunine, Erich Karkoschka, Lyn R. Doose, Trent M. Hare, Donna M. Galuszka, Elpitha Howington-Kraus, Peter H. Smith, D. Cook, Tammy L. Becker, Randolph L. Kirk, Elisabeth A. McFarlane, and Bashar Rizk

Subjects
geography, geography.geographical_feature_category, Radiometer, Fluvial, Shoal, Astronomy and Astrophysics, Terrain, Fault (geology), Tectonics, symbols.namesake, Space and Planetary Science, Erosion, symbols, Titan (rocket family), Geomorphology, Geology
Abstract

The Descent Imager/Spectral Radiometer (DISR) aboard the Huygens Probe took several hundred visible-light images with its three cameras on approach to the surface of Titan. Several sets of stereo image pairs were collected during the descent. The digital terrain models constructed from those images show rugged topography, in places approaching the angle of repose, adjacent to flatter darker plains. Brighter regions north of the landing site display two styles of drainage patterns: (1) bright highlands with rough topography and deeply incised branching dendritic drainage networks (up to fourth order) with dark-floored valleys that are suggestive of erosion by methane rainfall and (2) short, stubby low-order drainages that follow linear fault patterns forming canyon-like features suggestive of methane spring-sapping. The topographic data show that the bright highland terrains are extremely rugged; slopes of order of 30° appear common. These systems drain into adjacent relatively flat, dark lowland terrains. A stereo model for part of the dark plains region to the east of the landing site suggests surface scour across this plain flowing from west to east leaving ∼100-m-high bright ridges. Tectonic patterns are evident in (1) controlling the rectilinear, low-order, stubby drainages and (2) the “coastline” at the highland–lowland boundary with numerous straight and angular margins. In addition to flow from the highlands drainages, the lowland area shows evidence for more prolific flow parallel to the highland–lowland boundary leaving bright outliers resembling terrestrial sandbars. This implies major west to east floods across the plains where the probe landed with flow parallel to the highland–lowland boundary; the primary source of these flows is evidently not the dendritic channels in the bright highlands to the north.

Published
2007

8. Rain, winds and haze during the Huygens probe's descent to Titan's surface

Author

Bashar Rizk, Michael Küppers, Athena Coustenis, Stefan Schröder, John E. Moores, M. Bushroe, Peter Lanagan, C. de Bergh, Lyn R. Doose, B. Grieger, Randolph L. Kirk, A. Eibl, G. M. Prout, R. Kramm, Paul S. Smith, K. Holso, Robert West, Laurence A. Soderblom, Bruno Bézard, S. Engel, Fritz Gliem, E. Lellouch, L. E. Dafoe, Mark R. Rosiek, Jonathan I. Lunine, C. See, Brent A. Archinal, Martin G. Tomasko, P. Rueffer, H. U. Keller, Elpitha Howington-Kraus, Elisabeth A. McFarlane, D. Cook, Tammy L. Becker, M. Combes, Nicolas Thomas, Mark T. Lemmon, Erich Karkoschka, Sylvain Douté, Bernard Schmitt, Lunar and Planetary Laboratory [Tucson] (LPL), University of Arizona, Astrogeology Science Center [Flagstaff], United States Geological Survey [Reston] (USGS), 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), Laboratoire de Planétologie de Grenoble (LPG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut fur Datenverarbeitung, Technische Universität Braunschweig = Technical University of Braunschweig [Braunschweig], Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Department of Physics, Texas A&M University [College Station], Istituto di Fisica dello Spazio Interplanetario (IFSI), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Physikalisches Institut [Bern], Universität Bern [Bern] (UNIBE), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Max Planck Institute for Solar System Research (MPS), Consiglio Nazionale delle Ricerche (CNR), and Universität Bern [Bern]

Subjects
Haze, 010504 meteorology & atmospheric sciences, Extraterrestrial Environment, Rain, Wind, Atmospheric sciences, 01 natural sciences, Methane, symbols.namesake, chemistry.chemical_compound, AEROSOLS, 0103 physical sciences, Atmosphere of Titan, AGGREGATE PARTICLES, 010303 astronomy & astrophysics, Stratosphere, 0105 earth and related environmental sciences, AMMONIA, Multidisciplinary, Life on Titan, Atmosphere, Ice, Tholin, Humidity, Space Flight, MODEL, chemistry, 13. Climate action, SIMULATION, ENTRY, symbols, Environmental science, Tropopause, Titan (rocket family)
Abstract

International audience; The irreversible conversion of methane into higher hydrocarbons in Titan's stratosphere implies a surface or subsurface methane reservoir. Recent measurements from the cameras aboard the Cassini orbiter fail to see a global reservoir, but the methane and smog in Titan's atmosphere impedes the search for hydrocarbons on the surface. Here we report spectra and high-resolution images obtained by the Huygens Probe Descent Imager/Spectral Radiometer instrument in Titan's atmosphere. Although these images do not show liquid hydrocarbon pools on the surface, they do reveal the traces of once flowing liquid. Surprisingly like Earth, the brighter highland regions show complex systems draining into flat, dark lowlands. Images taken after landing are of a dry riverbed. The infrared reflectance spectrum measured for the surface is unlike any other in the Solar System; there is a red slope in the optical range that is consistent with an organic material such as tholins, and absorption from water ice is seen. However, a blue slope in the near-infrared suggests another, unknown constituent. The number density of haze particles increases by a factor of just a few from an altitude of 150 km to the surface, with no clear space below the tropopause. The methane relative humidity near the surface is 50 per cent.

Published
2005
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9. Imaging Photopolarimeter on Pioneer Saturn

Author

Martin G. Tomasko, Lyn R. Doose, L. R. Baker, J. S. Gotobed, C. E. Kenknight, James J. Burke, John W. Fountain, Larry W. Esposito, Mahendra P. Wijesinghe, Peter H. Smith, R. N. Strickland, J. Degewij, Robert S. McMillan, Tom Gehrels, C. Blenman, G. McLaughlin, E. Beshore, C. Stoll, R. L. Kingston, D. L. Coffeen, R. Murphy, B. Dacosta, and N. D. Castillo

Subjects
Physics, Brightness, Multidisciplinary, Rings of Saturn, Astronomy, Scale height, Polarization (waves), law.invention, Telescope, symbols.namesake, law, Physics::Space Physics, symbols, Satellite, Astrophysics::Earth and Planetary Astrophysics, Titan (rocket family), Saturn's hexagon
Abstract

An imaging photopolarimeter aboard Pioneer 11, including a 2.5-centimeter telescope, was used for 2 weeks continuously in August and September 1979 for imaging, photometry, and polarimetry observations of Saturn, its rings, and Titan. A new ring of optical depth2 x 10(-3) was discovered at 2.33 Saturn radii and is provisionally named the F ring; it is separated from the A ring by the provisionally named Pioneer division. A division between the B and C rings, a gap near the center of the Cassini division, and detail in the A, B, and C rings have been seen; the nomenclature of divisions and gaps is redefined. The width of the Encke gap is 876 +/- 35 kilometers. The intensity profile and colors are given for the light transmitted by the rings. A mean particle size less, similar 15 meters is indicated; this estimate is model-dependent. The D ring was not seen in any viewing geometry and its existence is doubtful. A satellite, 1979 S 1, was found at 2.53 +/- 0.01 Saturn radii; the same object was observed approximately 16 hours later by other experiments on Pioneer 11. The equatorial radius of Saturn is 60,000 +/- 500 kilometers, and the ratio of the polar to the equatorial radius is 0.912 +/- 0.006. A sample of polarimetric data is compared with models of the vertical structure of Saturn's atmosphere. The variation of the polarization from the center of the disk to the limb in blue light at 88 degrees phase indicates that the density of cloud particles decreases as a function of altitude with a scale height about one-fourth that of the gas. The pressure level at which an optical depth of 1 is reached in the clouds depends on the single-scattering polarizing properties of the clouds; a value similar to that found for the Jovian clouds yields an optical depth of 1 at about 750 millibars.

Published
1980
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10. Analysis of Raman scattered LY-α emissions from the atmosphere of Uranus

Author

Martin G. Tomasko, Lyn R. Doose, Roger V. Yelle, and Darrell F. Strobel

Subjects
Physics, Scattering, Uranus, Astronomy, Atmosphere, symbols.namesake, Geophysics, symbols, General Earth and Planetary Sciences, Atmosphere of Uranus, Atomic physics, Rayleigh scattering, Raman spectroscopy, Raman scattering, Line (formation)
Abstract

A line at 1280 A, due to Raman scattering of solar Lyman alpha (Ly-alpha) in the atmosphere of Uranus, has been detected by the Voyager Ultraviolet Spectrometer. The measured intensity of 40 + or - 20 R implies that 200 R to 500 R of the measured 1500 R Ly-alpha intensity at the subsolar point is due to Rayleigh scattering of the solar line. The presence of Rayleigh and Raman scattering at 1216 A suggests that the Uranian atmosphere is largely devoid of absorbing hydrocarbons above the 0.5 mbar level. The most natural explanation of this depletion is very weak vertical mixing equivalent to an eddy coefficient on the order of 200 sq cm/sec between 0.5 mbar and 100 mbar.

Published
1987
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11. Nature of the stratospheric haze on Uranus: Evidence for condensed hydrocarbons

Author

Sushil K. Atreya, Martin G. Tomasko, K. Rages, Shelly K. Pope, Paul N. Romani, and James B. Pollack

Subjects
Atmospheric Science, Materials science, Haze, Analytical chemistry, Soil Science, Aquatic Science, Oceanography, Atmospheric sciences, chemistry.chemical_compound, Geochemistry and Petrology, Earth and Planetary Sciences (miscellaneous), Stratosphere, Earth-Surface Processes, Water Science and Technology, chemistry.chemical_classification, Number density, Ecology, Diacetylene, Uranus, Paleontology, Forestry, Aerosol, Geophysics, Hydrocarbon, chemistry, Space and Planetary Science, Atmospheric chemistry
Abstract

We have used a number of models to analyze Voyager images of Uranus obtained at several high phase angles to derive physical and chemical properties of particulate matter present in the planet's lower stratosphere. These models include a multiple‐scattering algorithm for plane parallel atmospheres, a spherical atmosphere code for performing limb inversions, a microphysical model of aerosol formation, growth, and sedimentation, and a photochemical model of methane photolysis. We obtain definitive evidence for the presence of aerosols at pressure levels ranging from a few millibars to about 100 mbar. There are two possible sets of particle properties that can fit radiances observed close to but somewhat interior to the limb at several phase angles in four visible wavelength bands. The low‐density solution is characterized by particles having a modal radius and number density equal to 0.13 ± 0.02 µm and 2 ± 1 particles/cm³, respectively, at a pressure level of 44 mbar. The alternative, high‐density solution is characterized by particles having a modal radius that is 0.6–0.7 times that of the low‐density solution at the reference level and a density that is 2 orders of magnitude larger. Since the high‐density solution implies a mass production rate for the stratospheric aerosols that is much larger than those that can plausibly be supplied by photochemically produced gases that condense, whereas the low‐density solution does not, we favor the low‐density solution. Inversion of narrow‐angle, high‐resolution images of the limb provides a definition of a variable that provides a measure of the amount of aerosol scattering at high phase angles. The vertical profile of this variable shows a decrease of several orders of magnitude from pressure levels of tens to a few millibars. This decrease is due chiefly to the particle size of the aerosols becoming small compared to a wavelength. Above the base of the stratosphere the aerosol optical depth is approximately 0.01 in the mid‐visible. A major source for the stratospheric aerosols is the condensation of ethane, acetylene, and diacetylene gas species at pressure levels of approximately 14, 2.5, and 0.1 mbar, respectively. These gases are produced at much higher altitudes by solar UV photolysis of methane and diffuse to the lower stratosphere, where they condense. In addition, diacetylene is also produced photochemically within its condensation region. Condensation of locally produced diacetylene may represent a significant fraction of the total hydrocarbon condensation. Such a local source of condensation may be required by the inversions to the limb profiles, which indicate that at least half of the ice condensation occurs at altitudes above the 5‐mbar level. The hypothesis that the stratospheric particles are made of hydrocarbon ices is supported by the approximate agreement between the total ice condensation rate predicted by the methane photochemical model and the aerosol mass production rate derived for the low‐density solution of the Voyager data. The aerosol mass production rate derived from the Voyager data is equal to 2–15 × 10−17 g/cm²/s. Additional but weaker support for this hypothesis is provided by the Voyager radio occultation temperature profiles. It is suggested that solar UV radiation promotes solid state chemistry within the lower order hydrocarbon ices, resulting in the production of polymers capable of absorbing at visible wavelengths. Thus this altered material could play a key role in the planet's heat budget. Ethane, acetylene, and diacetylene ices evaporate at approximately the 600‐, 900‐, and 3000‐mbar levels of the upper troposphere. The polymeric material is expected to evaporate at pressures in excess of the evaporation level for diacetylene.

Published
1987
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12. The Imaging Photopolarimeter Experiment on Pioneer 11

Author

Lyn R. Doose, E. Beshore, J. P. Elston, Martin G. Tomasko, C. Blenman, John W. Fountain, A. L. Baker, N. D. Castillo, Tom Gehrels, W. Swindell, C. E. Kenknight, J. H. Kendall, Y.-P. Chen, R. A. Norden, L. R. Baker, and D. L. Coffeen

Subjects
Multidisciplinary, Scattering, Polarimetry, Astronomy, Optical polarization, Galilean moons, Photometry (optics), Jupiter, symbols.namesake, Planet, Physics::Space Physics, symbols, Astrophysics::Solar and Stellar Astrophysics, Natural satellite, Astrophysics::Earth and Planetary Astrophysics, Physics::Atmospheric and Oceanic Physics, Astrophysics::Galaxy Astrophysics, Geology
Abstract

For 2 weeks continuous imaging, photometry, and polarimetry observations were made of Jupiter and the Galilean satellites in red and blue light from Pioneer 11. Measurements of Jupiter's north and south polar regions were possible because the spacecraft trajectory was highly inclined to the planet's equatorial plane. One of the highest resolution images obtained is presented here along with a comparison of a sample of our photometric and polarimetric data with a simple model. The data seem consistent with increased molecular scattering at high latitudes.

Published
1975
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13. Solar and thermal radiation in the Venus atmosphere

Author

Fredric W. Taylor, Lawrence A. Sromovsky, V. I. Moroz, Martin G. Tomasko, Henry E. Revercomb, A. P. Ekonomov, B.E. Moshkin, John T. Schofield, and D. Spänkuch

Subjects
Physics, Earth's energy budget, Atmospheric Science, biology, Atmospheric models, Aerospace Engineering, Astronomy and Astrophysics, Venus, Radiation, biology.organism_classification, Atmospheric sciences, Atmosphere, Atmosphere of Venus, Geophysics, Space and Planetary Science, Thermal radiation, Physics::Space Physics, Astrophysics::Solar and Stellar Astrophysics, General Earth and Planetary Sciences, Astrophysics::Earth and Planetary Astrophysics, Atmospheric optics
Abstract

Attention is given to the solar and thermal radiation fields of Venus. Direct measurements and the results of numerical models based on direct measurements are presented. Radiation outside the atmosphere is considered with emphasis placed on global energy budget parameters, spectral and angular dependences, spatial distribution, and temporal variations of solar and thermal radiation. Radiation fluxes inside the atmosphere below 90 km are also considered with attention given to the solar flux at the surface, solar and thermal radiation fluxes from 100 km to the surface, and radiative heating and cooling below 100 km.

Published
1985
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14. Nature of the Ultraviolet Absorber in the Venus Clouds: Inferences Based on Pioneer Venus Data

Author

Robert W. Boese, Martin G. Tomasko, James B. Pollack, J. E. Blamont, A. Ian F. Stewart, Lawrence Travis, Boris Ragent, Larry W. Esposito, and Robert G. Knollenberg

Subjects
Physics, Multidisciplinary, Atmospheric models, biology, Venus, Albedo, medicine.disease_cause, biology.organism_classification, law.invention, Astrobiology, Photometry (optics), Atmosphere of Venus, Orbiter, law, medicine, Radiative transfer, Ultraviolet
Abstract

Several photometric measurements of Venus made from the Pioneer Venus orbiter and probes indicate that solar near-ultraviolet radiation is being absorbed throughout much of the main cloud region, but little above the clouds or within the first one or two optical depths. Radiative transfer calculations were carried out to simulate both Pioneer Venus and ground-based data for a number of proposed cloud compositions. This comparison rules out models invoking nitrogen dioxide, meteoritic material, and volatile metals as the source of the ultraviolet absorption. Models involving either small ( approximately 1 micrometer) or large ( approximately 10 micrometers) sulfur particles have some serious difficulties, while ones invoking sulfur dioxide gas appear to be promising.

Published
1979
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15. Particulate matter in the Venus atmosphere

Author

Boris Ragent, V.P. Shari, Larry W. Esposito, Victor Lebedev, Martin G. Tomasko, and M. Ya. Marov

Subjects
Atmospheric Science, Haze, biology, Aerospace Engineering, Astronomy and Astrophysics, Venus, Particulates, Atmospheric sciences, biology.organism_classification, Atmospheric composition, Atmosphere of Venus, Geophysics, Space and Planetary Science, Particle-size distribution, General Earth and Planetary Sciences, Environmental science, Atmospheric optics
Abstract

The paper presents a summary of the data currently available (June 1984) describing the planet-enshrouding particulate matter in the Venus atmosphere. A description and discussion of the state of knowledge of the Venus clouds and hazes precedes the tables and plots. The tabular material includes a precis of upper haze and cloud-top properties, parameters for model-size distributions for particles and particulate layers, and columnar masses and mass loadings.

Published
1985
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16. The absorption of solar energy and the heating rate in the atmosphere of Venus

Author

Martin G. Tomasko, Lyn R. Doose, and Peter H. Smith

Subjects
Atmospheric Science, Solar constant, Meteorology, Solar zenith angle, Aerospace Engineering, Venus, Atmospheric sciences, Solar irradiance, Atmosphere of Venus, Coronal mass ejection, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Galaxy Astrophysics, Zenith, Physics, biology, business.industry, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, biology.organism_classification, Solar energy, Geophysics, Space and Planetary Science, Physics::Space Physics, General Earth and Planetary Sciences, Astrophysics::Earth and Planetary Astrophysics, business
Abstract

The Solar Flux Radiometer (LSFR) experiment on the large probe of the Pioneer Venus (PV) mission made detailed measurements of the vertical profile of the upward and downward broadband flux of sunlight at a solar zenith angle of 65.7°. These data have been combined with cloud particle size distribution measurements on the PV mission to produce a forward-scattering model of the Venus clouds. The distribution of clouds at high altitudes is constrained by measurements from the PV orbiter. Below the clouds the visible spectrum and flux levels are consistent with Venera measurements at other solar zenith angles. The variations in the optical parameters with height and with wavelength are summarized in several figures. The model is used to evaluate the solar heating rate at cloud levels as a function of altitude, solar longitude, and latitude for use in dynamical studies.

Published
1985
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17. Upper limits on possible photochemical hazes on Pluto

Author

John Stansberry, Jonathan I. Lunine, and Martin G. Tomasko

Subjects
Physics, Solar System, Haze, Atmospheric model, Atmospheric sciences, Photochemistry, Methane, Aerosol, Astrobiology, Pluto, Atmosphere, chemistry.chemical_compound, Geophysics, chemistry, Planet, General Earth and Planetary Sciences
Abstract

The suggestion by Elliot et al., (1989) that a haze layer near the surface of Pluto may be photochemical in origin and similar to the aerosol hazes in the atmospheres of other outer solar system bodies is evaluated. The nature of hazes which may be produced in the Hubbard et al., (1989) atmosphere is explored as well. It is concluded that the very low pressure in Pluto's atmosphere requires an aerosol production rate equal to the total maximum methane photolysis rate expected at Pluto.

Published
1989
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18. Preliminary Results of the Solar Flux Radiometer Experiment Aboard the Pioneer Venus Multiprobe Mission

Author

N. D. Castillo, Martin G. Tomasko, William L. Wolfe, Peter H. Smith, Alan W. Holmes, James M. Palmer, and Lyn R. Doose

Subjects
Physics, Multidisciplinary, Radiometer, Meteorology, biology, business.industry, Cloud cover, Venus, biology.organism_classification, Solar energy, Atmospheric sciences, Atmosphere of Venus, Atmosphere, Altitude, Physics::Space Physics, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, business, Zenith
Abstract

The solar flux radiometer aboard the Pioneer Venus large probe operated successfully during its descent through the atmosphere of Venus. Upward, downward, and net fluxes from 0.4 to 1.0 micrometers were obtained at more than 390 levels between 185 millibars (at an altitude of approximately 61 kilometers) and the surface. Fluxes from 0.4 to 1.8 micrometers were also obtained between 185 millibars and about the level at which the pressure was 2 atmospheres. Data from 80 to 185 millibars should be available after additional decoding by the Deep Space Network. Upward and downward intensities in a narrower band from 0.59 to 0.66 micrometers were also obtained throughout the descent in order to constrain cloud properties. The measurements indicate three cloud regions above the 1.3-atmosphere level (at an altitude of approximately 49 kilometers) and a clear atmosphere beneath that level. At the 67 degrees solar zenith of the probe entry site, some 15 watts per square meter are absorbed at the surface by a dark ground, which implies that about 2 percent of the solar energy incident on the planet is absorbed at the ground.

Published
1979
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19. The Imaging Photopolarimeter Experiment on Pioneer 10

Author

C. Blenman, W. Swindell, Tom Gehrels, L. R. Baker, Martin G. Tomasko, D. L. Coffeen, Lyn R. Doose, J. H. Kendall, G. Best, J. Hämeen-Anttila, Robert J. Baker, A. Clements, C. Ken Knight, and N. D. Castillo

Subjects
Physics, Multidisciplinary, Polarimetry, Astronomy, Visible radiation, Polarization (waves), law.invention, Galilean moons, Telescope, symbols.namesake, law, Physics::Space Physics, High spatial resolution, symbols, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics, Remote sensing, Blue light
Abstract

A 2.5-centimeter telescope aboard Pioneer 10 is capable of making two-dimensional spin-scan maps of intensity and polarization in red and blue light at high spatial resolution. During the recent flyby of Jupiter, a large quantity of imaging and polarimetric data was obtained on Jupiter and the Galilean satellites over a wide range of phase angles.

Published
1974
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20. IUE observations of Solar System objects

Author

Tobias Owen, R. Wilson, Albert Boggess, Arthur L. Lane, H. W. Moos, Martin G. Tomasko, F. H. Schiffer, Tom Gehrels, A. Holm, F. Macchetto, P. M. Gondhalekar, T. R. Gull, P. M. Perry, E. Hamrick, B. E. Turnrose, D. C. Evans, Garry E. Hunt, Charles A. Barth, and R. R. Conway

Subjects
Physics, Solar System, Multidisciplinary, Planetary science, Solar spectra, Planet, Astronomy, Natural satellite, Mars Exploration Program
Abstract

During the scientific commissioning phase of IUE several spectra were acquired from objects residing in the Solar System. The activities focused on testing numerous parameters which would indicate the usefulness of IUE for planetary science. It seems that IUE can successfully tackle many important questions and the data analysis and interpretation of the initial set of observations has begun.

Published
1978
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22. The thermal balance of venus in light of the Pioneer Venus Mission

Author

Verner E. Suomi, Fredric W. Taylor, D. J. Martonchik, Henry E. Revercomb, Pete Smith, Robert W. Boese, Gerald Schubert, Martin G. Tomasko, Alvin Seiff, L. A. Sromovsky, James B. Pollack, Andrew P. Ingersoll, and Curtis Covey

Subjects
Atmospheric Science, Opacity, Soil Science, Venus, Aquatic Science, Oceanography, Atmospheric sciences, law.invention, Atmosphere of Venus, Atmosphere, Orbiter, Geochemistry and Petrology, law, Earth and Planetary Sciences (miscellaneous), Earth-Surface Processes, Water Science and Technology, Physics, Ecology, biology, Paleontology, Forestry, Atmospheric temperature, biology.organism_classification, Geophysics, Heat flux, Space and Planetary Science, Thermal radiation, Astrophysics::Earth and Planetary Astrophysics
Abstract

Instruments flown on the Pioneer Venus orbiter and probes measured many of the properties of the atmosphere of Venus which control its thermal balance and support its high surface temperature. Estimates based on orbiter measurements place the effective radiating temperature of Venus at 228±5 K, corresponding to an emission of 153±13 W/m², and the bolometric Bond albedo at 0.80±0.02, corresponding to a solar energy absorption of 132±13 W/m². Uncertainties in these preliminary values are too large to interpret the flux difference as a true energy imbalance. A mode of submicron particles is suggested as an important source of thermal opacity near the cloud tops to explain the orbiter and probe thermal flux measurements. Comparison of the measured solar flux profile with thermal fluxes computed from the measured temperature structure and composition shows that the greenhouse mechanism explains essentially all of the 500 K difference between the surface and radiating temperatures of Venus. Precise comparison of the observed and computed value of this difference is hindered by uncertainties in the local variability of H_(2)O and in the thermal opacity of CO_2 and H_(2)O at high temperature and pressure. The directly measured thermal flux profiles at the small probe sites are surprisingly large and variable in the lower atmosphere. Observed zonal and meridional circulation are qualitatively as required to produce the observed uniformity of temperature structure. However, the present lack of quantitative estimates of the horizontal and vertical dynamical heat transports implied by these measurements is a significant gap in the understanding of the thermal balance of the atmosphere of Venus.

Published
1980
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23. Hydrodynamics of the Helium Core Flash

Author

Martin G. Tomasko

Subjects
Physics, chemistry.chemical_element, Astronomy and Astrophysics, Mechanics, Helium flash, Astrophysics, Horizontal branch, Core (optical fiber), Flash (photography), chemistry, Space and Planetary Science, Stellar mass loss, Stellar evolution, Helium, Silicon-burning process
Published
1970
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