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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
Scientific American(四)月
This is Scientific American's 60-Second Science. I'm Cynthia Graber. This will just take a minute. If we want to learn more about our planet and other planets in the universe, we can get some help from stars that are long dead and gone. Thats what U.
Scientific American(一)月
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
英语新闻
BEIJING, Nov. 7 (Xinhuanet) -- A huge asteroid will pass closer to Earth than the moon on Tuesday, but experts say there is no cause for alarm. Asteroid 2005 YU 55 will pass about 300-thousand kilometers from the earth. The giant space rock is about
英语新闻
BEIJING, June 28 (Xinhuanet) -- A truck-sized asteroid passed over the Atlantic Ocean within 7,500 miles of the Earth on Monday, according to NASA's Jet Propulsion Laboratory. The space rock, called asteroid 2011 MD, is the second space rock to zip e
英语新闻
NASA has announced that an Asteroid will pass closer to Earth than the TV satellites that surround the planet. NASA says that the celestial visitor has no chance of impacting the Earth and is known as 2012 DA14. A group of amatuer astronomers discove
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