Rocks on Mars still harbour organic molecules after billions of years

Adjust Comment Print

A reminder: Organic molecules aren't necessarily produced by organisms; they're just chemical compounds that contain carbon. In chemistry, almost all molecules containing both carbon and hydrogen are organic compounds. Meteorites are constant pummeling Mars, and many of them contain carbon.

'With these new findings, Mars is telling us to stay the course and keep searching for evidence of life, ' said Thomas Zurbuchen, associate administrator for the Science Mission Directorate at Nasa headquarters.

NASA's Curiosity rover has uncovered organic material in an ancient lakebed and confirmed a seasonal cycle of methane - offering the strongest evidence yet of potential life, past or even present, on the Red Planet.

NASA officials discuss the findings of the Mars Curiosity rover. Mars2020 will shed light on the organic molecules-and prepare a sample that some future mission could bring back to Earth. Sadly, most scientists dismissed this claim in the decade that followed - finding other explanations for the rock's formation.

On Mars, organic molecules could have been produced by some form of either present or past lifeforms. "The first one would be life, which we don't know about".

Another mission, Mars InSight, is heading to Mars right now to study the geological life of the planet. Curiosity has detected large organic molecules inside ancient Martian rocks, as well as methane cycles now active on the planet.

NASA's Curiosity Mars Rover snaps a self-portrait at a site called Vera Rubin Ridge on the Martian surface in February 2018 in this image obtained on June 7, 2018. "Short of taking a picture of a fossil in a rock on Mars, [finding life there] is extremely hard to do scientifically", says Chris Webster, a chemist at the Jet Propulsion Laboratory and lead author of the methane study.

Today, scientists are announcing they've discovered conclusive evidence that several organic compounds are indeed found on the Red Planet.

The term "organic" means something different to a chemist than it does to a produce manager at a grocery store.

The discovery proves that while Mars is inhospitable today, it previously allowed for "liquid water" to pool, meaning a water lake inside Mars' Gale Crater could have once supported life, NASA said in an announcement on Tuesday. So they looked elsewhere. The Martian surface is bombarded with radiation that can degrade organic compounds, explains Eigenbrode.

"These clathrates lock the methane inside a water-ice crystal structure and are incredibly stable for millions of years until environmental conditions change and suddenly they can release that gas", says Duffy.

"[Curiosity's] molecular observations do not clearly reveal the source of the organic matter in [Gale Crater]".

With future missions, scientists may be able to figure out whether or not the organic compounds are indeed biosignatures.

NASA will use both these discoveries to inform the design of its upcoming Mars 2020 rover.

The new study reveals the discovery of complex and diverse organic compounds in more detail, however. The Wikipedia article on "organic matter" makes the point: "Organic molecules can also be made by chemical reactions that don't involve life". "I think we're moving toward extant [the opposite of extinct] life detection again".

"You're seeing a factor of three change in the methane in the atmosphere of Mars".

Comments