Paleoenvironmental context in searching for past life on Mars
astrobio
Abstract: The search for life beyond Earth occupies exploration efforts of space agencies and researchers, and captures the imagination of the public. Mars is a top Solar System candidate in this quest because of its multiple, once habitable environments of surface liquid water that may have harboured microbial life at a time when Earth’s own biosphere was getting underway billions of years ago. Yet, validation of possible signals of past life in Martian rocks will likely require sample return..