Life on Mars: A Definite Possibility Astrobiology Magazine

This much is known: At some point in Mars’s past, at least one region of the planet was drenched in water. Ancient Mars provided a habitat suitable for life as we know it. What kind of organism might have lived there? And is life lying dormant there still, just waiting for things to warm up a bit? No one can say. But one scientist, taking cues from earthly bacteria, has a pretty good idea of how a martian microbe could survive.