Submission + - Martian methane created by lifeforms? (spacefellowship.com)
skywatcher2501 writes: The quantity of methane gas on Mars cannot be caused in such quantities by chemical processes of disintegrating meteors entering the atmosphere. So two theories remain: either the gas is a by-product of a lifeform's metabolism, or it is created as a by-product of reactions between volcanic rock and water.
