Ice-ocean exchange processes in the Jovian and Saturnian satellites

Abstract:

A growing number of satellites in the outer solar system likely have global oceans beneath their outer icy shells. While the presence of liquid water makes these ocean worlds compelling astrobiological targets, the exchange of heat and materials between the deep interior and the surface also plays a critical role in promoting habitable environments. I will review ice-ocean exchange processes in outer solar system satellites that are the best candidates to host subsurface oceans: the icy Galilean satellites Europa, Ganymede, and Callisto and the Saturnian satellites Enceladus and Titan. Geophysical, geochemical, and geological observations will be combined to summarize our current state of understanding of their interiors and surface exchange processes. Potential mechanisms for driving exchange processes upward from the ocean floor and downward from the satellite surface will then be reviewed, which are primarily based on numerical models of ice shell and ocean dynamics and complemented by terrestrial analog studies. Future missions to explore these exo-oceans will further revolutionize our understanding of ice-ocean exchange processes and their implications for the habitability of these worlds.