Monitoring the mesospheric CO2 ice clouds by OMEGA/MEx

Abstract:

Along seven consecutive Martian years, we have discovered and systematically monitored the appearance of CO₂ ice clouds, mapping large areas in latitude, longitude and date. These observations have been made from large (at apoapsis) to close (at pericenter) distances, thus with varying resolutions. We have identified the proper locations, altitude and seasons of these clouds. During the past years, we have observed a temporal shift in the occurrence of the clouds, preceded by the evolution of dust clouds, possibly acting as nucleation site for the CO₂ clouds. We shall present these new results, and discuss them in the framework of cloud formation processes.