Mars’s Environment Shown to Be Hostile, but Not Untenable for Earthly Microbes Scientific American

Microbes similar to those on Earth would have a tough time surviving the harsh environment of Mars, but it is not inconceivable that they could persist there given a little protection, according to a new study. The finding supports similar, previous work and lends credence to the theory that if microbial life ever arose on Mars, it could exist below the planet’s surface to this day.
Mars is in most respects a terrible habitat for life as we know it: winter temperatures can dip below –100 degrees Celsius, the atmosphere contains little oxygen, and without the benefit of a robust ozone layer the Martian surface is bombarded with ultraviolet (UV) solar radiation.