TITAN’S NORTH POLE: A VIEW FROM THE END OF CASSINI (Invited Presentation)

Global oceans were once thought to hide beneath Titan’s hazey atmosphere, but Cassini revealed that lakes and seas of liquid hydrocarbons are almost exclusively found north of 60N. Thus, Titan’s north pole is one of the few places in the solar system where hydrology actively changes the landscape. Evidence from mapping the surface’s spectral, radar, and topographic characteristics reveals processes both familiar and bizarre are at work. Evaporite deposits are found at the bottoms of some empty lakebeds, suggesting that the distribution of liquids is dynamic on at least geological timescales. Lake basins resemble karstic morphologies on Earth, but it is unclear whether such erosion is efficient enough on Titan given that the fraction of soluble organics within the resistant water-ice crust not known. Furthermore, observations suggest some of the lake basins have tall thin, ramparts which seem to defy many of the lake formation hypotheses. Here we review the state of knowledge of Titan’s north pole from Cassini and present results from geomorphological and spectral investigations into the nature of the terrain and implications for fluvial and lacustrine processes.