radioactive

Since Mars doesn't have easily accessible radioactive elements, the nuclear fuel needs to come from Earth along with the reactor.

So, bit by bit, people emerge from the rubble on foot, contaminated with radioactive fallout, carrying what little they may have left.

Help from surrounding cities will have a hard time entering the disaster zone and even if they can, the radioactive contamination will make it risky to get too close.

Deep below the surface some bacteria would not notice much of any of this, as they are still kept warm by the radioactive decay of elements in the earth’s core.