An ultraviolet scanner that identifies organic matter in soils by reacting with a certain chemical compound is being tested and may be used on a future Mars lander or rover to search for life.
As reported by Internetnews.com, the ultraviolet light reacts with polycyclic aromatic hydrocarbons (PAHs), which may be one of the earliest forms of organic material in the universe, being found on both comets and meteorites. PAHs molecules fluoresce when excited by UV light.
"Since PAHs are found on meteorites, we would expect some of that material to fall from space onto the surface of Mars," said Martin Fisk, Professor of Marine Geology at Oregon State University, as reported by Oregon State University. "But we also know the surface is bombarded by ultraviolet light and cosmic rays, which would destroy organic matter. Computer simulations, including those carried out at University College London, suggest that the organic material is protected under the surface of Mars, down below a meter or so, and can be brought up via a drill and identified."
The scanner needs to be light enough to be flown and strong enough to survive the minus-120 degree Celsius temperatures of the Martian night. If these issues can be solved, perhaps the scanner will be part of the European Space Agency's ExoMars mission slated for 2013 that will be looking for evidence of life on Mars.
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