Identifying the Potential Biosphere of Mars

TL;DR

This paper identifies regions on Mars with the highest potential for current liquid water, based on geological features like gullies and craters, to guide future searches for microbial life.

Contribution

It develops a method to locate near-surface liquid water on Mars by analyzing gullies and rampart craters, highlighting key areas for astrobiological exploration.

Findings

Gullies and craters at specific depths indicate potential liquid water sources.

Low latitude gullies and deep craters are prime targets for water exploration.

Shallow aquifer discharge likely forms many gullies on Mars.

Abstract

Our current knowledge of life on Earth indicates a basic requirement for liquid water. The locations of present liquid water are therefore the logical sites to search for current life on Mars. We develop a picture of where on Mars the regions with the highest potential near-surface liquid water abundance can be found through a study of gullies. We also use rampart craters to sound the depth of water ice on Mars and where the highest concentrations of water ice occur. We estimate that low latitude gullies and rampart craters with depths greater than 100 m at 30 degrees (absolute) latitude, greater than 1.3 km at 35 degrees and greater than 2.6 km at 40 degrees latitude will give access to current liquid water environments capable of supporting microbial life. Our data is most consistent with the formation of these gullies through shallow aquifer discharge. These features should therefore be high priority targets for further study and high-resolution imaging with HiRISE.