Presentation #218.02D in the session “Titan Surface and Interior”.
Titan, the largest moon of Saturn, is a prime candidate for future space exploration. It is the only planetary body in our solar system, besides Earth, that has liquid (methane) on its surface and a thick, nitrogen-rich atmosphere. The RADAR instrument on NASA’s Cassini spacecraft mapped the surface of Titan and detected an unusually low number of impact craters compared to nearby Saturnian satellites. The low crater count is likely a result of atmospheric shielding, and erosion and burial of craters. This is similar to the reduced number of craters seen on Earth, as a result of weathering and erosion, compared to the heavily cratered lunar surface. Earth and Titan are comparable because erosion and burial are some of the main processes responsible for crater degradation on both surfaces, making Earth a strong analogue for studying Titan’s craters. There are 201 confirmed craters on Earth which have been identified by a combination of field and laboratory studies. Of these craters, 67 are buried and therefore unobservable from orbit. In addition, craters formed in marine environments (also present on Titan) lack significant surface topography that may prevent them from being recognized from orbital satellites. This study proposes to determine the percentage of exposed terrestrial craters that can be recognized with synthetic aperture radar data, as an analogue for Titan. Radar data from two different sensor bands will be used, allowing for the investigation of the roughness of craters at centimeter to decimeter scales. Preliminary characterization of 40 terrestrial craters shows that ~50% are distinctly visible in radar images. A complete study will help us to infer the number of unobservable impact craters on Titan. An accurate crater population for Titan will help us to determine constraints on the age of its surface, a value which is critical for models of the formation and evolution of Titan. All of these factors will help us to determine a comprehensive history and understanding of Titan, one of the most astrobiologically significant planetary bodies in our solar system.