New research shows that our aspirations to grow potatoes on Mars may be a little premature. Results of a new study indicate that the thin Martian atmosphere and the ultraviolet radiation it allows to reach the planet's surface interact with chemical compounds called perchlorates to create a deadly environment for bacteria.
We have known that there were perchlorates on the surface of the Red Planet since the 1970s when the Viking 1 and 2 spacecraft landed there. We've confirmed this with other probes since that time, and until recently that fact has actually been viewed in an encouraging light. That's because although perchlorates — made from oxygen and chlorine — are toxic to humans, bacteria tend to thrive in their presence, using them for energy. Perchlorates also lower the point at which water melts, which offered still more hope for the existence of bacterial life on Mars.