On the Feasibility of Informative Biosignature Measurements Using an Enceladus Plume Organic Analyzer

Abstract

The icy moons of Saturn and Jupiter are high priority locations in which to search for biomarkers of life elsewhere in our solar system. In particular, the ice plumes that jet out through the ice surface at Enceladus provide an enticing opportunity to sample the organic components of its subsurface ocean for possible biosignatures while ameliorating challenges of planetary protection. Extensive high- and hypervelocity light gas gun experiments, the first to model the Enceladus ice plume encounter accurately, have demonstrated that organic-rich ice particles can be efficiently captured using plume transits at and below 3 km s−1 without significant organic destruction. Realistic scenarios for the amount of ice captured and for the ability of organic chemical analysis instruments, especially microfluidic capillary electrophoresis with laser-induced fluorescence, to produce meaningful detection levels for biosignatures are then presented and compared with results from terrestrial models. This analysis indicates that an Enceladus plume fly-by mission carrying microfluidic instrumentation is capable of biosignature measurements with a sensitivity and analytical capability that is highly informative about the extent of extraterrestrial biological processes.