Fewer asteroids are menacing Earth than we thought — and we know where 90 percent of them are

NASA recently repurposed a satellite called WISE that had completed its mission with all instruments intact and quite a bit of fuel. Renaming the mission NEOWISE, the space agency gave the satellite a new job: map the entire volume of space in the vicinity of Earth's orbit around the sun, looking for every possible… »9/30/11 1:20pm9/30/11 1:20pm