Asteroid to miss Mars, only 1/10,000 chance
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BEIJING, Jan. 11 (Xinhuanet)-- The odds of asteroid striking Mars has been effectviely ruled out, U.S. media reported on Friday.
Tracking measurements of asteroid 2007 WD5 from four observatories have so greatly reduced uncertainties about its Jan. 30 close approach to Mars that the odds of an impact have dropped to 1 in 10,000, the Near-Earth Object Program at NASA's Jet Propulsion Laboratory said in a posting on its Web site Thursday.
Scientists said the best estimate was for the asteroid to pass at a distance of more than 16,000 miles from the surface of Mars, or at worst, no closer than 2,480 miles.
With an estimated diameter of about 164 feet (50 meters), the asteroid is similar in size to the object that slammed into northern Arizona about 50,000 years ago to create Meteor Crater, NASA scientists have said.
Earlier analysis of the space rock's trajectory suggested that, if it did impact Mars, it could slam into the planet's surface at about 30,000 miles per hour (48,280 kph), release about 3 megatons of energy and leave a crater about a half-mile (0.8-km) wide, they added.
