英语听力：探索发现 2014-07-11 BBC 地平线：陨石的真相-26

搜索关注在线英语听力室公众号：tingroom，领取免费英语资料大礼包。

 

And I’ve got the Sun in the centre and the third planet out here would be that of the Earth. The red dots in here are actually Near-Earth asteroids. The green ones are the regular Main-Belt asteroids. 

 

There are over 9,000 Near-Earth asteroids. But there’s one type that’re particularly concerned to locate, those asteroids that are over one kilometer in diameter. An Earth impact with one of these would spell disaster. Tim’s data reveals that there are 900 asteroids bigger than a kilometer in those dangerous Near-Earth orbits. But he has some good news.

 

Right now, there’s no information that any of those large objects will hit the Earth in the next 100 years. So we’re safe from impact of those objects for at least 100 years. So there are no catastrophic asteroid² impacts on the horizon. But there are still dangers out there. 

分享到：