This project is an effort to constrain the surface and atmospheric composition of Saturn's moon Titan. Spectroscopic observations of the surface, whether from in situ spacecraft or Earth-based telescopes, are complicated by Titan's thick atmosphere, through which the light must traverse, and the composition and structure of which are poorly known. The key element of this project is the observation of a grazing-angle specular reflection of the Sun from one of Titan's hydrocarbon lakes by the Visual and Infrared Mapping Spectrometer (VIMS) on the Cassini spacecraft. The Principal Investigator (PI) intends to exploit the wavelength independence of the specular reflection to isolate the atmospheric contributions to the total spectrum. The proposed work consists of three specific tasks: (1) to explore the composition of Titan's polar atmosphere using the transmission spectrum obtained from the specular reflection; (2) to constrain the composition of possible surface organic species using VIMS spectra in the 5-micron transmission window corrected for atmospheric effects, and (3) to map the extent of surface water ice exposures using the corrected spectra. The project would support the work of a graduate student and an undergraduate student at an institution that has not previously been active in astronomy research, providing an opportunity to broaden participation in science among residents of Idaho. This project is jointly funded by the Division of Astronomical Sciences and the Office of the Experimental Program to Stimulate Competitive Research (EPSCoR).
