Chemical properties and variation of the ice rich surfaces of the biggest TNOs and satellites

Séminaire IPAG de Frederic Merlin (Université Paris 7 (Denis Diderot), jeudi 13 février 2014 à 11h00, IPAG seminar room

Ices, and especially water ice, are ubiquitous in the universe. Ices made up of other moderately volatile substances in the outer solar system are known or presumed to exist, for example, on Europa, Ganymede and Callisto (NH3), Titan (CH4 and other carbohydrates), Triton and Pluto (N2, CH4, C2H6), on the surface of the major Saturnian satellites, (CO2, CH3OH, NH3OH), or on Charon (NH3OH). From all these observations we can enumerate several icy species present in the solar system that are consistent with a proto-stellar environment and are the basis of a more complex chemistry. The spectral investigation of these bodies gives us details on the role of ices governing the formation and evolution of planetary systems, that could, for instance, favor the conditions for the development of complex organic molecules. I will present the spectral properties of the surface of several Trans-Neptunian Objects and those of Triton, the biggest satellite of Neptune. I will focus my analyses on the diversity of the chemical properties of their surfaces as well as their variability during the last decades in order to state on possible spatial and temporal variations. Finally, I will examine the physical phenomena that could be responsible of the chemical properties and their evolution.