The Curious Case of Methane on Mars

Today NASA held a press conference to announce the results of two papers released in Science this week: One on atmospheric methane, and one on organics in the soil, both from Curiosity rover data.

The history of methane detections on Mars is a tumultuous one. In 2004, the European Space Agency announced that Mars Express had detected small amounts of methane in the martian atmosphere. This was exciting news because on Earth, 95% of methane comes from biological sources—mostly microbes and cows, but we’re pretty sure there are no cows on Mars.