Chemical Compositional Analysis for Titan's Surface
Résumé
The investigation of Titan's surface chemical composition is of great importance for the understanding of the atmosphere-surface-interior system of the moon, as well as its astrobiological potential. The Cassini Visual and infrared Mapping Spectrometer (VIMS) has provided a sequence of spectra showing the diversity of Titan's surface spectrum from flybys performed during the 13 years of Cassini's operation. We have created detailed geomorphological maps for a number of extensive regions at 1:800,000 scale, such as the Afekan region [1], the South Belet region [2], and the Soi crater region [3] using Cassini SAR and non-SAR data, using the methodology presented by [1] and [2]. The VIMS coverage of the regions allowed for detailed analysis of spectra of different locations and geomorphological nature using a radiative transfer technique [4;5] and a mixing model [6;7], yielding compositional constraints on Titan's optical surface layer. We have also analyzed VIMS data and retrieved the chemical composition of other regions of interest such as Tui Regio, Sotra Patera, Hotei Regio and more. The combination of the geomorphological characterization of regions and the constraint of their chemical composition help on the formulation of hypotheses on the origin and evolution of Titan's regional geology