astroengine writes "Although the idea of "infecting" the Red Planet with our germs is nothing new, one microbiologist believes the next Mars rover may have a higher chance of becoming a microbe lifeboat. Andrew C. Schuerger, of the University of Florida and the Space Life Sciences Lab at NASA's Kennedy Space Center in Florida, believes the problem could lie in the way NASA's Mars Science Laboratory (MSL) will land on the Red Planet — wheels first. Previous Mars rovers have sat atop a lander platform for at least two Martian days (sols) before venturing into the regolith; any surviving bacteria attached to their wheels were therefore killed by the harsh UV light that bathes Mars. As the MSL's wheels will immediately make contact with the regolith straight after entry, there might be an increased chance of contaminating Mars with terrestrial germs. But still, as Schuerger admits, the risks are tiny."
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