英语听力:探索发现 2014-07-16 BBC 地平线:陨石的真相-28(在线收听) |
An asteroid strike would create a huge explosion. NASA feared this might even be mistaken for a nuclear bomb. We wanted folks to know this was a natural event by Mother Nature rather than some sort of man-made event like a missile or something dreadful.
Information passed rapidly up the chain of command. NASA headquarters notified the White House that this was coming. Everyone wanted to know where it would strike. NASA predicted a remote area of the Nubian Desert. 2:45 in the moring, NASA were proved right.
The explosion created a vast fireball burning as hot as the Sun. it was so big and so hot this image was captured by a weather satellite. And yet the object that caused it was only four metres across, smaller than the asteroid which exploded over Chelyabinsk.
I definitely think the impact was a wake-up call. I have to admit I never thought I’d see that in my career where we would discover something and it would hit the Earth later that day. What I was worrying about that impact was that the asteroid was too small to detect until it was very, very close to the Earth. Of course, for Chebarkul, it wasn’t even spotted until it was already here. But we are getting better at spotting smaller asteroids.
On the same day that Chebarkul was hit, another asteroid, similar in size to the object that created the Barringer Crater, came within just 28,000 kilometres of the Earth.
|
原文地址:http://www.tingroom.com/lesson/yytltsfx/2014/273568.html |