A NASA robot has found more building blocks for life on Mars, the most complex organic matter yet from 3.5 billion-year-old rocks on the surface of the red planet, the U.S. space agency said on Thursday.
While the new results are far from a confirmation of life on Mars, scientists believe they support earlier hypotheses that the Red Planet was once clement and habitable for microbial life. The organic compounds aren't even the first molecules of their kind found on Mars, though they are the oldest.
"A lot of us were left scratching our heads trying to figure out, "What does this mean?' Then we turned around and realised, 'Let's just go and find more", said Dr Eigenbrode of NASA's Goddard Space Flight Centre. Organic matter can be one of several things: a record detailing ancient life, a food source for life or something that exists in the place of life. Samples of ancient mudstone yielded a diversity of organic molecules in SAM's oven-and in a separate study, five years' worth of atmospheric samples gathered by SAM tracked fluctuating levels of methane that peaked in the Martian summer. Another noticed the methane levels around Curiosity varied by the season.
Methane is considered the simplest organic molecule. Scientists already knew billions of years ago liquid water existed on Mars and the crater had an ancient lake. Maybe there are subsurface Martian bacteria eating that methane, Tanya Harrison, director of research for Arizona State University's Space Technology and Science ("NewSpace") Initiative, told Gizmodo.
But Curiosity's data are providing a clearer and more conclusive picture of the conditions and processes on Mars - and what it may have been like on the Red Planet billions of years ago, when conditions were more suitable for life.
"It's a gas in the atmosphere of Mars that really shouldn't be there", says NASA Jet Propulsion Lab scientist Chris Webster. Sharp, the 3-mile-high mound in the middle of Gale Crater whose layers of sediments serve as individual chapters in the geological history of Mars. Only a few of the organic molecules, sulfur-bearing carbon rings called thiophenes, were abundant enough to be detected directly, Eigenbrode says.
The Curiosity rover, launched in 2011 with about $2.5 billion worth of scientific equipment with the intent of exploring and analyzing Mars' Gale Crater.
But NASA managers say the new discoveries show the agency's Mars exploration plans are on the right track.
"This is all possible because of Curiosity's longevity".
As winter falls, gases are once again trapped in ice cages, helping explain at least some of the vanishing methane.
NASA's Mars Atmosphere and Volatile Evolution Mission (MAVEN) spacecraft effectively ruled out cosmic origins following its analysis of the dust left after a close encounter with the comet Siding Spring in 2014. The host of the session, assistant director of science for communications in NASA's Planetary Science Division Michelle Thaller, began by clearing up any rumors that the agency would announce that they had found alien life. "The first one would be life, which we don't know about". We don't know if that methane is ancient, we don't know if it's modern. "To do that you either have to find an outcrop at the surface that has been recently exposed ... or you have to drill deep", she said.