Chemical composition analysis of Titan’s equatorial and midlatitude surface regions
- 1Hellenic Space Center, Athens, Greece
- 2LESIA–Observatoire de Paris, CNRS, UPMC Univ. Paris 06, Univ. Paris-Diderot, Meudon, France
- 3Czech University of Life Sciences Prague, Faculty of Environmental Sciences, Suchdol, 16500, Praha, Czech Republic
- 4Department of Earth, Planetary, and Space Sciences, University of California Los Angeles, Los Angeles, CA, USA
- 5Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
- 6Department of Earth, Atmospheric, and Planetary Science, Massachusetts Institute of Technology, Cambridge, MA, USA
- 7Institut LATMOS/IPSL, UVSQ Université Paris-Saclay, Sorbonne Université, CNRS, France
- 8Institut Universitaire de France, Paris, France
- 9Institut de Planétologie et d’Astrophysique de Grenoble, Université Grenoble Alpes, CNRS, Grenoble, France
The Cassini cameras and especially the Visual and infrared Mapping Spectrometer 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. The investigation of Titan’s surface chemical composition is of great importance for the understanding of the atmosphere-surface-interior system of the moon. The Soi crater region with the well-preserved Soi crater in its center, spans from Titan’s equatorial regions to high northern latitudes. This provides a rich diversity of landscapes, one that is also representative of the diversity encountered across Titan. We mapped this region at 1:800,000 scale using Cassini SAR and non-SAR data and produced a geomorphological map using the methodology presented by [1] and [2]. The VIMS coverage of the region allowed for detailed analysis of spectra of 262 different locations using a radiative transfer technique [3;4] and a mixing model [5;6], yielding compositional constraints on Titan’s optical surface layer. Additional constraints on composition on the near-surface substrate were obtained from microwave emissivity. We identified 22 geomorphological units, 3 of which were not previously described, and derived combinations of top surface materials between dark materials, tholin-like materials, water-ice, and methane. We found no evidence of CO2 and NH3 ice. We also observe empty lakes as far south as 40°N, which mark the most southern extent of Titan’s north polar lakes. We use the stratigraphic relations between our mapping units and the relation between the geomorphology and the composition of the surface layers to build hypotheses on the origin and evolution of the regional geology.
[1] Malaska, M., et al. (2016), Icarus 270, 130; [2] Schoenfeld, A., et al. (2021), Icarus 366, 114516; [3] Solomonidou, A., et al. (2014), J. Geophys. Res. Planets, 119, 1729; [4] Solomonidou, A., et al. (2016), Icarus, 270, 85; [5] Solomonidou, A., et al. (2018), J. Geophys. Res. Planets, 123, 489; [6] Solomonidou, A., et al. (2020), A&A 641, A16.
How to cite: Solomonidou, A., Schoenfeld, A., Malaska, M., lopes, R., Coustenis, A., Birch, S., Le Gall, A., and Schmitt, B.: Chemical composition analysis of Titan’s equatorial and midlatitude surface regions, Europlanet Science Congress 2022, Granada, Spain, 18–23 Sep 2022, EPSC2022-776, https://doi.org/10.5194/epsc2022-776, 2022.
