A Salty, Martian Meteorite Offers Clues to Habitability

Life as we know it requires energy of some sort to survive and thrive. For plants, that source of energy is the Sun. But there are some microbes that can survive using energy from chemical reactions. Some of them even eat salts, such as perchlorates.

Perchlorate (ClO4-) is a highly oxidized form of chlorine. Perchlorate salts are found not only on Earth, but also on Mars. They’re highly toxic to humans but are useful for components such as rocket fuel.

It was good news for future Martian explorers when in 2008 an instrument on the Mars Phoenix polar lander discovered evidence of perchlorate in a flat valley informally called “Green Valley.” Four years later, the new NASA Curiosity rover uncovered more of the substance near the equator.

Now, there’s stronger evidence that the salt is widespread. New research shows that a martian meteorite recovered on Earth has perchlorate in it as well as other salts, namely chlorate and nitrate.