Pioneering space scientist David McKay died Feb. 20, 2013 at the age of 76. He trained the Apollo moonwalkers in geology and led a famous 1996 study that suggested the Mars meteorite ALH84001 may ... more 
Pioneering space scientist David McKay died Feb. 20, 2013 at the age of 76. He trained the Apollo moonwalkers in geology and led a famous 1996 study that suggested the Mars meteorite ALH84001 may contain signs of past Red Planet life. less 
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SPACE.com | Photo By NASA
Mon, Feb 25, 2013 5:36 PM EST