Martian Soil Undergoes Intense Scrutiny of Curiosity

The Curiosity rover's Chemistry and Mineralogy (CheMin) instrument is all set to analyze what minerals are present in the solid sample that is being ingested inside the rover, a capability at the core of the two year mission.

"We are crossing a significant threshold for this mission by using CheMin on its first sample," said Curiosity's project scientist, John Grotzinger of the California Institute of Technology in Pasadena. "This instrument gives us a more definitive mineral-identifying method than ever before used on Mars: X-ray diffraction. Confidently identifying minerals is important because minerals record the environmental conditions under which they form."

The material that is being analyzed by CheMin is the sieved portion from the third scoop that is being collected by Curiosity from Rocknest. This sample was delivered by rover's robotic arm to CheMin's opened inlet funnel on the rover's deck on Oct 17.

The previous day, the rover shook the scooped the material inside sample-processing chambers in order to scrub the internal surfaces of any residue carried from Earth. One earlier scoopful was also used for cleaning. The team will carry repeated cleaning methods before delivery of a future sample to the rover's other internal analytic instrument, the Sample Analysis at Mars investigation. This team studies all the samples of chemistry.

The images taken after Curiosity collected its second scoop of Rocknest material on Oct. 12 revealed smaller bits of light-toned material in the scooped sample. This led to discarding that scoopful rather than using it to scrub the processing mechanisms. Scientists assess these smaller, bright particles to be native Martian material, not from the spacecraft.

"We plan to learn more both about the spacecraft material and about the smaller, bright particles," said Curiosity Project Manager Richard Cook of NASA's Jet Propulsion Laboratory, Pasadena. "We will finish determining whether the spacecraft material warrants concern during future operations. The native Mars particles become fodder for the mission's scientific studies."

With the help of Curiosity's 10 instruments the researchers will assess whether the study area has ever offered environmental conditions favorable for microbial life.