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Meanwhile, a 45-meter wide asteroid1 has hurtled safely past earth after it came within 27-thousand kilometers, making it the closest known flyby for a rock of its size.
The asteroid, named 2012 DA14 came closer to earth than many communication and weather satellites.
Scientists have been monitoring its movement all year round. Jim Green is Planetary Science Division Director at the American space agency NASA.
"We are safe. DA14, we call it, was discovered last year. We've been monitoring its movement all throughout the solar system."
Green said NASA was currently monitoring more than nine-thousand asteroids2, of which scientists believe 1,800 are reasonably large.
The 2012 DA14 asteroid was too small to see with the naked eye even at its closest approach over the Indian Ocean near Sumatra.
The best viewing locations, with binoculars3 and telescopes, were in Asia, Australia and Eastern Europe.
Daniel Hestroffer, an astronomer4 at the Paris Observatory5, said it is not necessary to worry about large asteroids having disastrous6 collision with earth in the near future.
"For the larger one, now we start to be more confident, to predict almost all for the very big ones, and we have been able to predict that there will be no catastrophic collision with the earth for the next century. But for the intermediary sized ones, we still need to work hard on it."
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1 asteroid | |
n.小行星;海盘车(动物) | |
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2 asteroids | |
n.小行星( asteroid的名词复数 );海盘车,海星 | |
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3 binoculars | |
n.双筒望远镜 | |
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4 astronomer | |
n.天文学家 | |
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5 observatory | |
n.天文台,气象台,瞭望台,观测台 | |
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6 disastrous | |
adj.灾难性的,造成灾害的;极坏的,很糟的 | |
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