Is There Life on Mars?
More than four years after they landed on Mars, NASA's twin robot explorers, Spirit and Opportunity , have lasted 16 times longer and driven 20 times farther than expected. Along the way, they've endured the worst Martian storm ever recorded and survived near-fatal software glitches, a broken wheel and hair-raising climbs and descents on steep slopes. And since May 25, 2008, they've had new company on the red planet: NASA's Phoenix probe, which dramatically "tasted" water ice on the planet in July. NOVA "Is There Life on Mars?" showcases the latest scientific results from the rovers and Phoenix , which are poised to reveal provocative new clues in the tantalizing search for water and life on the Red Planet.