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Project Progress

Co-Investigator David Grinspoon analyzed infall to the Titan system of both interplanetary and circum-Saturnian dust and ice particles to establish limiting exogenic fluxes of several elements, such as germanium and oxygen, which may be important in facilitating potential Titan metabolisms. Co-Investigator Steven Benner has identified some interesting possible chemical bases for life in liquid methane, but finds that they may depend on the supply of some relatively rare (in terms of cosmic abundance) elemental species, such as germanium. Grinspoon has adopted a formalism to interpret the Cassini dust measurements to make predictions of the limiting external fluxes of some of these potentially biologically important species. There are two primary sources: Interplanetary dust particles (IDPs) and E-ring particles (ERPs). ERP’s are generated by the plumes of Enceladus and extend past Titan. Grinspoon is modifying model calculations constrained by the Cassini CDA/HRD and ground based observations, as well as observations from previous spacecraft. Preliminary results suggest that IDPs are a larger source by an order of magnitude, but the ERP flux may dominate for oxygen and other interesting elements. Assuming chondritic abundances, he finds a very small flux of germanium and other trace elements of interest (arsenic, molybdenum).