英语听力：探索发现 2014-06-11 BBC 地平线：陨石的真相-13

 There it is!

 

Yep. It’s about 90 kilometres up, at that stage, travelling at 17.5 kilometres per second.

 

Using the different camera positions, scientists have pinpointed¹ the exact position at which the meteor entered the atmosphere. And by tracking the speed and angle of the shadows that the meteor casts, they’ve calculated its velocity². Together this is enough to tract³ back the asteroid⁴’s path from deep space. Although the asteroid and Earth orbits are different durations and at angles to one another, their clockwork regularity⁵ means that we were bound to collide. So this shows speeded up, obviously, three and a half hours, the last three and a half hours of the life of this little rascal⁶. 

 

Yeah, it’s nice to see it from the asteroid’s point of view. The thing to remember is that this asteroid has been in its orbit, going around the Sun, roughly once every two years. We believe…

 

Minding its own business.

 

Absolutely.

 

And unfortunately on February 15 it found a planet in the way. Sure enough, at all the 20 hours the meteor entered our atmosphere above Siberia. On this path and at this time, it was Chelyabinsk that took the full impact. But could there have been another scenario⁷? The meteorite⁸ landed at a latitude⁹ of 55 degrees north. Had it arrived just a few hours later, we would have been directly in its flight path.

1 pinpointed   

准确地找出或描述( pinpoint的过去式和过去分词 )； 为…准确定位

参考例句：

• His refusal to help simply pinpointed his cowardice. 他拒绝帮助正显示他的胆小。
• Computers pinpointed where the shells were coming from. 计算机确定了炮弹发射的位置。

2 velocity   

n.速度，速率

参考例句：

• Einstein's theory links energy with mass and velocity of light.爱因斯坦的理论把能量同质量和光速联系起来。
• The velocity of light is about 300000 kilometres per second.光速约为每秒300000公里。

3 tract   

n.传单，小册子，大片(土地或森林)

参考例句：

• He owns a large tract of forest.他拥有一大片森林。
• He wrote a tract on this subject.他曾对此写了一篇短文。

4 asteroid   

n.小行星；海盘车(动物)

参考例句：

• Astronomers have yet to witness an asteroid impact with another planet.天文学家还没有目击过小行星撞击其它行星。
• It's very unlikely that an asteroid will crash into Earth but the danger exists.小行星撞地球的可能性很小，但这样的危险还是存在的。

5 regularity   

n.规律性，规则性；匀称，整齐

参考例句：

• The idea is to maintain the regularity of the heartbeat.问题就是要维持心跳的规律性。
• He exercised with a regularity that amazed us.他锻炼的规律程度令我们非常惊讶。

6 rascal   

n.流氓；不诚实的人

参考例句：

• If he had done otherwise,I should have thought him a rascal.如果他不这样做，我就认为他是个恶棍。
• The rascal was frightened into holding his tongue.这坏蛋吓得不敢往下说了。

7 scenario   

n.剧本，脚本；概要

参考例句：

• But the birth scenario is not completely accurate.然而分娩脚本并非完全准确的。
• This is a totally different scenario.这是完全不同的剧本。

8 meteorite   

n.陨石；流星

参考例句：

• The meteorite in Jilin Exhibition Hall is believed to be the largest in the world.吉林展览馆的陨石被认为是世界上最大的。
• The famous Murchison meteorite smashed into the Australian ground in 1969.1969年著名的默奇森陨石轰然坠落在澳大利亚。

9 latitude   

n.纬度，行动或言论的自由(范围)，(pl.)地区

参考例句：

• The latitude of the island is 20 degrees south.该岛的纬度是南纬20度。
• The two cities are at approximately the same latitude.这两个城市差不多位于同一纬度上。