We may be one step closer to answering the most tantalizing cosmic question: Are we alone? Our loyal robotic explorers have been scouring Mars for evidence of life since the 1970s, when the Viking landers may have found and even destroyed it, according to one hypothesis. We may be one step closer to answering the most tantalizing cosmic question: Are we alone? Our loyal robotic explorers have been scouring Mars for evidence of life since the 1970s, when the Viking landers may have found and even destroyed it, accordi... [4794 chars]