Sondage du sous-sol martien par un radar basse-fréquence depuis un satellite en orbite basse : analyses physiques et préparation des données

摘要

On June 2003, the European Space Agency launched the Mars Express spacecraft toward Mars, with the MARSIS radar on board, for the mapping of the Martian subsurface and the detection of ice and liquid water. Our objectives were to perform a physical analysis of the measurement and to support the future data interpretation. To do so, we developed a MARSIS signal simulation based on MOLA topography of Mars's surface. Due to surface smoothness, we used the Facet Method and modeled the ground through a series of tangent planes that are 500m wide. The simulation includes an underground interface and ionosphere effects on the radar signal. Our results are presented and we test the ground and on board signal processing. A special focus has been set on the difference between North and South surface echoes. The satellite's orbital parameters are taken into account, allowing the simulation to be used for planning purposes.