Search Results - "Grard, Rejean"

Analytic theory of Titan’s Schumann resonance: Constraints on ionospheric conductivity and buried water ocean by Béghin, Christian, Randriamboarison, Orélien, Hamelin, Michel, Karkoschka, Erich, Sotin, Christophe, Whitten, Robert C., Berthelier, Jean-Jacques, Grard, Réjean, Simões, Fernando

“…► We have developed a theoretical model of Titan’s atypical Schumann resonance. ► Characteristics of atmospheric-subsurface cavity are constrained by Huygens…”
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Mercury: The Messenger and BepiColombo missions A concerted approach to the exploration of the planet by Grard, Réjean

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The electrical properties of Titan’s surface at the Huygens landing site measured with the PWA–HASI Mutual Impedance Probe. New approach and new findings by Hamelin, Michel, Lethuillier, Anthony, Le Gall, Alice, Grard, Réjean, Béghin, Christian, Schwingenschuh, Konrad, Jernej, Irmgard, López-Moreno, José-Juan, Brown, Vic, Lorenz, Ralph D., Ferri, Francesca, Ciarletti, Valérie

“…•We assess the dielectric constant and electrical conductivity of Titan’s ground at the Huygens landing site.•We analyse a fast change of electrical…”
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Comment on "An analysis of VLF electric field spectra measured in Titan's atmosphere by the Huygens probe" by J. A. Morente et al by Grard, Réjean, Berthelin, Stéphanie, Béghin, Christian, Hamelin, Michel, Berthelier, Jean-Jacques, López-Moreno, Jose J., Simões, Fernando

“…Comment on “An analysis of VLF electric field spectrameasured in Titan’s atmosphere by the Huygens probe”by J. A. Morente et al…”
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Missions to Mercury by Balogh, Andre, Grard, Rejean, Solomon, Sean C, Schulz, Rita, Langevin, Yves, Kasaba, Yasumasa, Fujimoto, Masaki

“…Issue Title: Mercury Mercury is a very difficult planet to observe from the Earth, and space missions that target Mercury are essential for a comprehensive…”
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Detection of near-surface ice on Mars with electromagnetic techniques on board future surface vehicles by Hamelin, Michel, Trautner, Roland, Grard, Réjean

“…After reviewing our knowledge about the presence of water on Mars and the potential advances that can be expected from the projects under development, we…”
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Electrostatic charging processes of balloon and gondola surfaces in the Earth atmosphere by Grard, Réjean

“…Electrostatic charging of balloons and gondolas is frequently observed, especially during ascents in the atmosphere. Charge buildup modifies the potential…”
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Photoemission on the surface of Mercury and related electrical phenomena by Grard, Réjean

“…Solar photons interact with the surface of Mercury due to the absence of an atmosphere. Photo-electrons are emitted from the sunlit hemisphere with a mean…”
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Solar Photon Interaction with the Martian Surface and Related Electrical and Chemical Phenomena by Grard, Réjean

“…A significant fraction of the solar EUV photons, with energies of up to 6 eV, penetrates the martian atmosphere and interacts with the surface of the planet…”
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The role of photoemission in the coupling of the Mercury surface and magnetosphere by Grard, Réjean, Laakso, Harri, Pulkkinen, Tuija I.

“…Photoelectrons are emitted from the surface of Mercury and take part in charge exchanges with the magnetosphere. We investigate the role of photoemission in…”
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Preface by Grard, Rejean

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USING SCHUMANN RESONANCE MEASUREMENTS FOR CONSTRAINING THE WATER ABUNDANCE ON THE GIANT PLANETS: IMPLICATIONS FOR THE SOLAR SYSTEM'S FORMATION by SIMOES, Fernando, PFAFF, Robert, MARTIN, Steven, ROWLAND, Douglas, SENTMAN, Davis, TAKAHASHI, Yukihiro, YAIR, Yoav, HAMELIN, Michel, KLENZING, Jeffrey, FREUDENREICH, Henry, BEGHIN, Christian, BERTHELIER, Jean-Jacques, BROMUND, Kenneth, GRARD, Rejean, LEBRETON, Jean-Pierre

“…The formation and evolution of the solar system is closely related to the abundance of volatiles, namely water, ammonia, and methane in the protoplanetary…”
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Detection of subsurface ice and water deposits on Mars with a mutual impedance probe by Trautner, Roland, Grard, Réjean, Hamelin, Michel

“…A mutual impedance probe, also called quadrupolar probe or permittivitymeter, measures the complex permittivity of materials with a spatial resolution…”
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Electrostatic charging processes of balloon and gondola surfaces in the Earth atmosphere by Grard, Rejean

“…Electrostatic charging of balloons and gondolas is frequently observed, especially during ascents in the atmosphere. Charge buildup modifies the potential…”
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Returns to Mercury: science and mission objectives by Grard, Réjean, Balogh, André

“…As the inner end-member of the planetary system, Mercury plays an important role in constraining and testing dynamical and compositional theories of planetary…”
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In situ observations of the ionized environment of Mars: the antenna impedance measurements experiment, AIM, proposed as part of the Mars advanced radar for subsurface and ionospheric sounding, MARSIS by Trotignon, J.G, Séran, H.-C, Béghin, C, Meyer–Vernet, N, Manning, R, Grard, R, Laakso, H

“…Although the priority is not very high, one of the scientific objectives of the Mars Express mission is to study the interaction of the Martian atmosphere with…”
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Detection of subsurface ice and water deposits on Mars with a mutual impedance probe by TRAUTNER, Roland, GRARD, Réjean, HAMELIN, Michel

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Detection of near-surface ice on Mars with electromagnetic techniques on board future surface vehicles : Geophysical detection of surface water on Mars by HAMELIN, Michel, TRAUMER, Roland, GRARD, Réjean

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An international program for Mercury exploration: synergy of MESSENGER and BepiColombo by McNutt, Ralph L., Solomon, Sean C., Grard, Réjean, Novara, Mauro, Mukai, Toshifumi

“…Mariner 10 has been the only spacecraft to visit the innermost planet Mercury. Its three flybys, more than 25 years ago, yielded the first view of this…”
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Influence of suprathermal electrons upon the transfer impedance of a quadrupolar probe in a plasma by Grard, Réjean

“…Measuring the coupling impedance of two dipoles in a plasma is a diagnostic technique which has been used with success for several decades in space and in the…”
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