December 3, 2012
Curiosity Finds Evidence Of Simple Organic Compounds On Mars
Lee Rannals for redOrbit.com - Your Universe Online
NASA announced at the American Geophysical Union meeting in San Francisco today that its Mars Curiosity rover has completed its first analysis of Martian soil, finding a complex chemistry within the Martian soil.
The space agency said its Curiosity rover has found water, sulfur and chlorine-containing substances among the samples taken from the rover's arm.
The latest find demonstrates Curiosity's ability to analyze diverse soil and rock samples over the next two years, NASA said.
Curiosity performed its first soil scoops at a location called Rocknest, and delivered the samples into its analytical instruments. The rover's laboratory includes the Sample Analysis at Mars (SAM) suite, and the Chemistry and Mineralogy (CheMin) instrument.
SAM helped analyze gases given off from the sand after heating the samples in a tiny oven. The instrument helps to check for organic compounds, which are chemicals that can be ingredients for life.
"We have no definitive detection of Martian organics at this point, but we will keep looking in the diverse environments of Gale Crater," SAM Principal Investigator Paul Mahaffy of NASA's Goddard Space Flight Center in Greenbelt, Maryland, said in a press release.
The APXS instrument and the Mars Hand Lens Imager (MAHLI) found on Curiosity's arm helped to confirm Rocknest has chemical-element composition and textural appearance similar to sites found by previous NASA rovers, Pathfinder, Spirit and Opportunity.
NASA selected Rocknest as the first soil scooping site because it has fine sand particles suited for scrubbing interior surfaces of the arm's sample-handling chambers. Sand is vibrated inside the chambers to remove residue from Earth.
"Active drifts on Mars look darker on the surface," said MAHLI Principal Investigator Ken Edgett, of Malin Space Science Systems in San Diego. “This is an older drift that has had time to be inactive, letting the crust form and dust accumulate on it."
NASA said Curiosity's CheMin instrument found the composition of the samples is about half common volcanic minerals and half non-crystalline materials like glass. SAM found information about ingredients present in much lower concentrations and about ratios of isotopes.
The water molecules found by SAM are not unusual to be found bound to sand or dust. However, NASA said that the quantity seen was higher than anticipated.
NASA said that SAM also "tentatively" identified the oxygen and chlorine compound perchlorate. This is a reactive chemical found in arctic Martian soil by NASA's Phoenix Lander. Reactions with other chemicals heated in SAM formed chlorinated methane compounds.
The space agency said the chlorine is of Martian origin, but the carbon could have been brought by Curiosity and detected by SAM's high sensitivity design.
"We used almost every part of our science payload examining this drift," said Curiosity Project Scientist John Grotzinger of the California Institute of Technology in Pasadena. "The synergies of the instruments and richness of the data sets give us great promise for using them at the mission's main science destination on Mount Sharp."