Eos Chasma, Mars: Regional setting for a potential landing site for astrobiology

The floor of Eos Chasma, centered at about 13.4°S and 41.5°W at an elevation of -3.5 km, is proposed as a future landing site on Mars. Deposits in this area were derived from a variety of sources, including chaotic terrain (interpreted to reflect the release of subsurface water) and possible paleolake materials, which could shed light on the astrobiological potential of Mars, climate history, and the evolution of the surface. Analyses of the physical properties of the proposed site suggest a rock abundance of 10-18% (based on Viking Orbiter Infrared Thermal Mapper data), set in a matrix of medium to coarse sands (based on Mars Global Surveyor Thermal Emission Spectrometer data), sparse covering by dust (based on albedo measurements), and a surface roughness of <1 to 1.7 in (derived from the Mars Orbiter Laser Altimeter). Although these attributes are within the engineering constraints for current lander designs, models of the atmosphere suggest that wind shear (generated primarily by the proximity to local topography, i.e., the Chasma canyon wall) might preclude the site with current landing systems.