title: Digging mars.
authors: University of Arizona, USA.
authors: Peter H
authors: PH
authors: Smith
mesh_terms: D018559:Exobiology; D005118:Extraterrestrial Environment / Q000737:chemistry; D018535:Mars; D013026:Space Flight / Q000295:instrumentation; D018531:Spacecraft / Q000295:instrumentation; D014481:United States; D018557:United States National Aeronautics and Space Administration