Monday, 17 December, 2018

NASA Finds Concentrated Batch Of Organic Molecules On Mars

The Curiosity Mars Rover The Curiosity Mars Rover
Theresa Hayes | 08 June, 2018, 09:26

Organic molecules were found in 3 billion-year-old sedimentary rocks near the surface.

The shocking discovery of molecules preserved in ancient bedrock suggest conditions on the Red Planet may once have housed life. Methane previously had been detected in Mars' atmosphere in large, unpredictable plumes.

A self-portrait of NASA's Curiosity Mars rover.

"There's three possible sources for the organic material", said astrobiologist Jennifer Eigenbrode of NASA's Goddard Space Flight Center in Maryland.

Regardless, the detection is a technical achievement, said Williford, because it demonstrates that organic molecules can persist near Mars's surface for billions of years. We might find even more evidence in future missions, too.

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.

Scientists have been seeking organic molecules on Mars ever since the 1976 Viking landers. The term "organic" is ambiguous - we often take it to mean "life-related" but it doesn't have to mean that.

"That is a good place for life to have lived if it ever existed on Mars", she said.

Inorganic carbon is carbon that is found in compounds that are completely unlike biological molecules. 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.

Since Curiosity landed on Mars in 2012, the rover has been exploring Gale Crater, a massive impact crater roughly the size of CT and Rhode Island, for geological and chemical evidence of the chemical elements and other conditions necessary to sustain life. But they're of interest to astrobiologists because they are the essential ingredients in all the chemistry that drives life on Earth.

"Are there signs of life on Mars?" asked Michael Meyer, lead scientist for the Mars Exploration Program at NASA Headquarters. "Both radiation and harsh chemicals break down organic matter", said Eigenbrode. What the study has done, though, is to propel the search for life on Mars higher up the list of worldwide space exploration priorities - giving space agencies ammunition to argue for a coordinated programme of missions to explore the Red Planet. This is different from previous measurements of methane on Mars, which could not be repeated.

"People have been wondering about whether there might be life on Mars forever and finally ... they've done all the tests they've modified everything to be able to show that in fact there's organic matter on Mars". Organic material can be produced without life.

"Because we see these coming off of the sample at high temperatures, what they're really telling us is that they're part of something larger, a macromolecule", she said.

That may be because numerous compounds, such as thiophene, methanethiol and dimethyl sulfide, had sulfur atoms in their molecular structure - which would strengthen the relatively fragile organic molecules, allowing them to survive the radiation bombarding the planet's surface for so long. "And the last one is geological processes, meaning the rock-forming processes themselves".

"We don't know, but these results tell us we are on the right track"'.

It's impossible to say whether ancient life explains the Martian organics, however.