CAPE CANAVERAL, Fla. — NASA’s Mars rover Curiosity has detected spikes of methane in the planet’s atmosphere. That suggests something is producing or venting the scientifically tantalizing gas, but no one knows what.
Most of Earth’s atmospheric methane comes from animal and plant life, and the environment itself. So Martian methane raises the question of past or present microbial life. Or the gas elevations could come from comet impacts or something else entirely.
The latest study, released Tuesday by the journal Science, indicates there’s less than half the expected amount of methane in the atmosphere around Curiosity’s location in Gale Crater. But over a full Martian year, the rover measured fairly frequent occurrences of tenfold increases in methane levels.
