NPR’s Science Friday – Curiosity Hits Paydirt: New Clues to Life on Mars

“Microbes may have once happily existed on the surface of Mars, according to chemical analysis of a sedimentary rock in the Red Planet’s Gale Crater. NASA geologist and exobiologist David Blake discusses evidence for an ancient freshwater lake in the crater, and describes the mineral-chomping microbes that might have thrived there.”