LOS ANGELES, June 24 (Xinhua) -- Near-Earth asteroid 2011 MD will whip past Earth on June 27, but will not pose any threat, NASA's Jet Propulsion Laboratory (JPL) said on Friday. The asteroid will pass only 12,000 kilometers (7,500 miles) above the E...
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This is Scientific American's 60-Second Science. I'm Karen Hopkin. Thisll just take a minute. Any school kid can tell you that comets are made of ice. That frozen water burning off is what gives comets their characteristic tails. But asteroids were g...
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