Ken Herkenhoff, U.S. Geological Survey

The polar regions represent a unique environment for determining the mechanisms of martian climate change over geological time. Answering the most urgent questions in Mars polar science will require the in situ application of terrestrial paleoclimate assessment techniques, including measurement of the ratios D/H and 18O/16O in ice or meltwater. Whether implemented with a single deep ice borehole or a series of shallow holes along a traverse, such a mission requires subsurface access to the polar layer deposits at sufficient depth to eliminate the possibility of recent surface alteration