Microphysics of icy seasonal processes on Mars and Pluto : hyperspectral imaging monitoring and experimental study.

• Main Author: Philippe, Sylvain
• Other Authors: Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes 2016-2019 (UGA 2016-2019 )-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes 2016-2019 (UGA 2016-2019 ), Université Grenoble Alpes, Bernard Schmitt, Pierre Beck
• Format: Doctoral or Postdoctoral Thesis
• Language: French
• Published: HAL CCSD 2016
• Subjects: Mars; Pluto; Polycristalline ice; Seasonal deposits; Hyperspectral imaging; Radiative transfer; Pluton; Glace polycristalline; Dépôts saisonniers; Imagerie hypserspectrale; Transfert radiatif; [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO]; polar night
• Online Access: https://theses.hal.science/tel-01560378; https://theses.hal.science/tel-01560378/document; https://theses.hal.science/tel-01560378/file/PHILIPPE_2016_diffusion.pdf

The condensation/sublimation cycle of CO2 controls the martian climate and, in winter, forms frozen seasonal deposits, contaminated with water ice and dust. This thesis’ objective is to unders- tand, characterize, and if possible, to quantify the different microphysical processes occuring in the seasonal deposits during this condensation/sublimation cycle, with the insight of experimental simulation of these processes inside the CarboN-IR experimental cell. The CO2 ice condensation in a polycristalline form on a mineral regolith, the modification of the CO2 ice condensation regime in the martian polar night due to the presence of non condensable gases, the stratification of water ice onto CO2 ice during the sublimation of the seasonal deposits and the increase of the albedo of CO2 slab ice during its springtime sublimation are all phenomena that have been reproduced successfully inside the experiemental cell. The CO2 slab ice condensation on the Martian surface has been observed during its formation, in autumn, at lower latitudes than polar night limit with hyperspectral imaging from the OMEGA spectrometer onboard of the Mars Express probe. Yet the farthest object explored in the solar system, Pluto, shares many similarities with Mars, parti- cularly a partial icy cover of its surface (of CH4, N2 and CO ices for Pluto) in equilibrium with its atmosphere. The evolution of these ices can be considered similar in terms of the surface pro- cesses affecting them : stratification of ices in function of their volatility during their sublimation or condensation at the surface, formation of slab ice . The hyperspectral imagery data (LEISA), provided by the New Horizons probe during its Pluto’s flyby in july 2015, allowed to determine the accurate cartography of chemical species at the surface, along with their physical state - the preliminary steps of any geological interpretation. Le cycle de condensation/sublimation du CO2 contrôle le climat martien et forme en hiver des dépôts saisonniers glacés, contaminés en ...