An Examination of Soil Crusts on the Floor of Jezero Crater, Mars

Martian soils are critically important for understanding the history of Mars, past potentially habitable environments, returned samples, and future human exploration. This paper examines soil crusts on floor Jezero crater encountered during initial phases Mars 2020 mission. Soil surface have been observed at other locations, starting with two Viking Lander missions. Rover observations show that also common across crater, revealed in 45 101 locations where rover wheels disturbed surface, 2 out 7 helicopter flights crossed wheel tracks, 4 8 abrasion/drilling sites. Most measured by SuperCam laser-induced breakdown spectroscopy (LIBS) instrument high hydrogen content fine-grained a visible/near infrared (VISIR) 1.9 µm H2O absorption feature. The Planetary Instrument X-ray Lithochemistry (PIXL) suggest presence salts rocks soils. correlation S Cl contents H LIBS measurements suggests present likely hydrated. On “Naltsos” target, magnesium sulfur correlated PIXL measurements, Mg is tightly points, suggesting hydrated Mg-sulfates. Environmental Dynamics Analyzer (MEDA) indicate possible frost events potential changes hydration Mg-sulfate salts. may therefore form relative humidity events, cementing together.