Classification - USDA

U.S. Geological Survey Astrogeology Science Center, 2255 Gemini Road, Flagstaff, AZ USA 86001. Institute for Applied Geosciences, University of Technology Darmstadt, Schnittspahnstrasse 9, 64257 Darmstadt, Germany. ... as well as targeting caves most suitable for establishment of underground astronaut bases on Mars. This process involves ... ................
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