Silence From Mars

NASA on Monday gave up trying to contact the missing Mars Polar Lander, confirming what had been suspected for more than a month: The $165 million spacecraft was dead on arrival. Engineers at NASA’s Jet Propulsion Laboratory listened for the spacecraft one last time and heard only silence. “It is closure in the sense that I think we did everything we could to re-establish contact, and, yes, it’s time to get on to other things,” said project scientist Richard Zurek. The spacecraft vanished Dec. 3 while trying to land on Mars. It was to have studied the atmosphere and dug for ice during a 90-day mission. Among the possible explanations for its failure to call home: The three-legged lander burned up in the atmosphere, crashed on Mars or tipped over on the rugged surface and damaged itself.