"Recently the technology has become available to perform these experiments during remote surveys of other planets," Storrie-Lombardi added.
In their experiment, the scientists created a fine, dusty soil by crushing a peridotite rock from a nickel mine in Riddle, Ore., that they say closely replicates the Martian surface material. A meteorite found in France, originating from Mars, consisted of 88 percent olivine, while the Oregon peridotite was 90 percent olivine.
They infused the peridotite granules with PAHs at a level of 50 parts per million, which is what they would expect to find on a meteorite, then took about a tablespoon of the soil and exposed it to different light waves from a meter away.
Using colored filters from the panoramic camera, or PanCam, that was the backup instrument for the Beagle 2-Lander, they were able to clearly identify as little as 1.5 micrograms of the organic material and pinpoint different PAHs by variations in their fluorescent response. The Beagle 2 made it to Mars in 2003, but was lost on approach and assumed to have crashed onto the Martian surface.
Two of the study's scientists Storrie-Lombardi and Jan-Peter Muller, of the Mullard Space Sciences Laboratory in the United Kingdom carried out the optic experiments in the laboratory and at Silver Lake, Calif., a well-known Mars analog study site. As part of their tests, they set up a rig that could work under different conditions not dissimilar from the final system that would be mounted on a Mars lander or rover.
"Being able to test the fluorescence signature both under laboratory conditions and in the field has been critical to being confident that such a system will work on the surface of Mars," said Muller, a co-author on the study and a professor of imaging at the University College London's Mullard Laboratory.
Andrew Coates, a co-author of the study and principal investigator of the international ExoMars PanCam te
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Oregon State University