GSA Annual Meeting in Indianapolis, Indiana, USA - 2018

Paper No. 90-12
Presentation Time: 11:05 AM


MACKENZIE, S.M., 11100 Johns Hopkins Road, Mail Stop 200-W230, Laurel, MD 20723-6099, TURTLE, Elizabeth, Applied Physical Laboratory, John Hopkins University, Laurel, MD 20723, LORENZ, Ralph, Applied Physics Lab, Johns Hopkins University, Laurel, MD 20723, RADEBAUGH, Jani, Department of Geological Sciences, Brigham Young University, Provo, UT 84602, BARNES, J.W., University of Idaho, Moscow, ID 83844 and TRAINER, M.G., NASA, Goddard Space Flight Center, Greenbelt, MD 20771

Dragonfly is a rotorcraft-lander mission concept to Saturn’s moon Titan currently being studied for NASA’s New Frontiers Program. Photolytic reactions in Titan’s atmosphere create haze particles that eventually fall to the surface. There, these complex organic particles get reworked by chemical and physical processes. With such a large reservoir of both liquid and solid organics as well as liquid water in the interior ocean and on the surface in the past, Titan is the premier location for studying prebiotic chemistry in the solar system. Dragonfly is designed to sample the surface and identify the chemical components available and processes at work to produce biologically relevant compounds. Aerial mobility enables sampling and other in situ observations to characterize the habitability of Titan's environment, past and present, at multiple locations.

Placing the samples in the proper geological context, however, will be key to understanding their astrobiological significance. In addition to the subsurface ocean, potentially habitable environments include transient liquid water oases created from cryovolcanic flows or impact into the ice crust. These different environments have different cooling times, so discerning whether sampled material comes from eroded crust, cryovolcanic flow, or impact melt, constrains the timescales for aqueous chemistry to have modified organic material. Dragonfly would conduct an imaging campaign to establish the local provenance of materials.

The geologic processes that govern the distribution of surface organics govern their availability to mix with liquid water or liquid methane at the surface, or with the subsurface ocean. Titan’s vast sand seas are a source of easily transported organics that could represent material collected from all over Titan. Measurements of the composition of the sand will help to determine the currently unknown process by which the sand particles form. Dragonfly would also conduct saltation experiments to establish how sands are transported across the surface. To investigate geologic processes with the potential to exchange material within Titan’s ice shell, Dragonfly would document structural geology and listen for seismic activity.