GEOLOGIC MAPPING OF CANDIDATE LANDING SITES FOR THE MARS-2020 ROVER MISSION

The scientific objectives of NASA’s next Mars rover mission, scheduled to launch in 2020, are (1) to characterize the geologic history of an astrobiologically-relevant ancient environment; (2) to investigate materials with high biosignature preservation potential; (3) to assemble a returnable cache of samples for possible future return to Earth; and (4) to contribute to the preparation for human exploration of Mars. In order to achieve the first three of these goals, the rover’s landing site must allow access to an ancient, habitable environment with a diverse set of geologic materials. Eight candidate sites that meet these criteria are currently under consideration. Understanding the distributions, stratigraphic relationships, and compositions of geologic units within the rover’s proposed field exploration area will be critical to the selection of the final landing site.

Here I present results and interpretations from the detailed mapping of candidate landing sites, incorporating high-resolution imaging, visible to near-infrared spectroscopy, and thermal inertia data from orbit. Initial work has focused on two sites with distinct ancient environments: Eberswalde crater, which contains a variety of sedimentary units interpreted to have formed in a long-lived, fluvio-lacustrine system; and Gusev crater, which contains diverse igneous and sedimentary units interpreted to have formed in a hydrovolcanic environment. The geologic mapping allows for the identification of proposed sampling locations within each 16 km x 14 km landing ellipse where the Mars-2020 rover can test specific hypotheses about geologic processes, ancient aqueous environments, habitability and potential biosignature preservation.