news.sciencemag.org
12-3-12
SAN FRANCISCO, CALIFORNIA-The first full analysis of martian soil by the Curiosity rover has detected simple carbon compounds that could be the first traces of past martian life ever found, NASA scientists announced here today at a press conference at the annual fall meeting of the American Geophysical Union. The catch is that Curiosity team members cant tell yet whether the organic matter was once alive, was never alive and drifted onto Mars from space, or was simply cooked up in Curiositys analytical instrument from lifeless bits of soil. Figuring out the ultimate source of the carbon in this organic matter-biological or not-will take time. "Curiositys middle name is Patience," cautioned Curiosity project scientist John Grotzinger of the California Institute of Technology in Pasadena.
Although Curiosity did find organic matter, the medias frenzied anticipation that preceded the press conference-and drove it into a ballroom to accommodate all the TV cameras-turned out to have been provoked by a misunderstanding. A reporter overheard Grotzinger praising the superb high-quality data being returned by the rover and assumed the remarks referred to an exciting discovery from Curiositys first thorough soil analysis. The rover had taken in fine soil particles, heated them, and passed the gases that the heating drove off through its mass spectrometer, which can separate and identify the gases by molecular weight. The only exciting result reporters could imagine was organic matter from life, and so the frenzy of anticipation began.
What Curiosity actually detected were trace amounts of three of the simplest possible carbon-containing compounds: a carbon atom with one, two, or three chlorine atoms attached in place of hydrogen atoms. According to Paul Mahaffy of NASAs Goddard Space Flight Center in Greenbelt, Maryland, and the principal investigator of Curiositys Sample Analysis at Mars (SAM) instrument package, these three chloromethanes were most likely generated in SAM. The heating may have decomposed a natural component of martian soil-the strong oxidizing agent perchlorate-which in turn could have broken down some form of carbon in the soil sample and chlorinated its carbon atoms.
The question would then become what form the carbon was in. It might have been big, complex organic molecules like amino acids, the molecular remains of long-dead martian organisms....
Continue Reading...
See Also:
MARS: "News [of Life] Would Trigger a Revolution in Human Perspectives Not Seen Since Copernicus"
Curiosity Finds Old Streambed on Mars (Photo)
Mars Curiosity Rover Makes Earthshaking Discovery; "This Data is Gonna be one for the History Books," says NASA SPACE NEWS MARS AUDIO