Does Mars Methane Indicate Life Underground? National Geographic News

Data obtained by the Mars Express probe that is currently orbiting the red planet show that water vapor and methane gas are concentrated in the same regions of the Martian atmosphere, the European Space Agency recently announced. The finding may have important implications for the possibility that microbial life could exist on Mars. If microbes are making methane in the Martian atmosphere as part of their living process, they would rely on water.