Has Curiosity found complex organics on Mars?

Space nuts may get an early Christmas present this year: rumors are flying that NASA is preparing to announce the discovery of organic molecules on Mars – a possible sign of life.

The Curiosity rover’s principal investigator, John Grotzinger of Caltech, told NPR yesterday that the rover’s Sample Analysis at Mars (SAM) instrument had produced some important results.

“This data is gonna be one for the history books. It’s looking really good,” he said.

Organic molecules are hard to find, not least because chemical salts  known as perchlorates, found in Martian soil, would generally destroy them when samples are heated.

But the SAM instrument heats samples more slowly, in such a way that organic molecules could in theory survive.

Even if organic molecules have been found, they aren’t necessarily a sign of life; after all, they’ve been discovered in meteorites. Really exciting would be the presence of complex organic molecules, which would be a pretty definitive sign.

There’s already plenty of evidence that there was once water on Mars, regarded as a prerequisite for life, and many scientists believe there may still be water beneath the surface.

A formal announcement on the new SAM data is likely to be made in about two weeks’ time, when NASA has double-checked its results. And it’s prefectly possible that the initial results won’t hold up to scrutiny; SAM’s already come a cropper once by detecting methane which turned out to be contamination from Earth.