October 19, 2012
Credit: Credit: NASA
LOS ANGELES — NASA’s Mars Science Laboratory (MSL) Curiosity team plans to position the exploratory rover to closely examine a bright speck of material the Jet Propulsion Laboratory (JPL)-based team now believes could be Martian in origin rather than “foreign object debris” as previously thought.
The 1 mm speck was discovered when the rover’s arm scooped out material for the sampling system as part of initial efforts to clean out the chemistry and mineralogy (CheMin) experiment, one of two ways that Curiosity is able to analyze powdered rock and soil samples. The brightness of the particle surprised scientists who last week had dismissed another bright object seen close to the rover as a piece of plastic that came to Mars with Curiosity.
As a result, “we dumped out the sample we took with scoop number two” says John Grotzinger, project manager of NASA’s MSL mission, at the California Institute of Technology.
The bright speck was “in the hole left by the scoop, so we didn’t know if there were things like this in the sample. It was more of a case of being cautious,” adds JPL MSL Project Manager Richard Cook.
But now, as NASA confirms the first full soil sample has been successfully ingested into the CheMin instrument, Grotzinger says the more precise targeting sampling devices on the rover’s arm will be used to look at the particle up close. “We hope to make that measurement within days,” says Grotzinger, who adds, “this thing could be something completely different to the silicates we’ve seen.”
The chief targeting instrument to be used will be the ChemCam, which incorporates a Thales-made laser capable of ionizing rock or soil up to 23 ft. away. As the target is zapped, the instrument observes the glowing spot of plasma with its telescopic lens and analyzes the light to identify chemical elements.
“Whatever it is, it seems to be very uncommon. We considered all the options to better understand what it might be and it’s a strong consensus that it’s something which represents a science opportunity and not an engineering threat,” Grotzinger adds.
There also remains some conjecture as to the source of the other bright debris.
Cook says “we haven’t been up close enough to see what the other objects [which measure 10 mm-20 mm in size] are, so we don’t know if they’re plastic or something else. We’re trying to determine the source of them. It could have come down during entry, descent and landing,” he adds.