Over the course of the last two-months Curiosity has observed a ten-fold increase in the concentration of methane on Mars. While the usual background level of methane on the red planet is a paltry one part per billion, this new discovery has lifted some researchers’ hopes that there may have once been life on Mars.
“Most of the methane on Earth is produced by biology, and the hope has been that ‘methane on Mars’ could be reduced to ‘life on Mars,’” said Chris Webster, senior research scientist at NASA’s JPL. Still, Webster added a caveat to his statement: “We cannot yet distinguish whether the high methane levels we’re seeing are being produced geochemically or biologically.”
Given the slim number of methane molecules wafting through Mars’ atmosphere, Curiosity’s task of finding the substance took some serious work. In its efforts to isolate methane Curiosity had to scrub carbon dioxide from its gas samples to capture a background reading. With that reading in place Curiosity continued to roam across Mars’ barren surface looking for a source. Surprisingly, over a 60-day slog the rover ran into elevated concentrations of methane on four separate occasions. Where they come from, though, is still anyone’s guess.
It is still uncertain whether a definitive source for these methane emissions will ever be located. However, another Martian rover is set to touch down on the planet in 2020. Maybe that machine will carry on Curiosity’s already fruitful search for life on Mars.
Image Courtesy of NASA