Electrochemical Characterization of Planetary Regoliths Using in-situ Electrical Spectroscopy

Future planetary science missions will focus on looking for evidence of past or present life in extreme environments. In addition to biosignatures on a global scale such cold arid planets (Mars) and icy worlds (Europa), localized geochemical systems that host gradients are also of great interest for determining the potential for life to thrive or to originate in these environments. A challenge in characterizing such redox sensitive geochemical systems is that they evolve over a relatively short lifetime (1-4 hrs) necessitating viable in-situ, non-destructive analytical techniques. Promising techniques for such studies are electrochemical methods, which are particularly suited for characterizing interfaces and chemical gradients. Given recent advancements in mobility systems (i.e., landers, large/small rovers, stationary probes, etc.), in-situ electrochemical-based instrumentations provide one of the most effective means of scientific analysis (i.e., interfacial adsorption, redox, transport dynamics, etc.) at a localized scale.

JPL has already made significant progress in developing these new technologies, particularly electrochemical impedance spectroscopies (EIS) for in-situ characterization of geochemical materials (i.e., soils ice mineralogy, and brines) and even life detection sensoring. We will present data showing the capability of using EIS in planetary regoliths under lunar and martian environmental conditions.