英语听力：自然百科 来自远古宇宙的光
时间：2019-01-22 作者：英语课 分类：自然百科2010年
英语课
When massive stars explode, they can produce gamma-ray bursts. The burst, reported in two papers in Nature, is the earliest descriptive event seen so far in our universe.
“When I received the text message about the gamma-ray burst, it came ultimately from the Swift satellite. Swift is an unusual satellite. At the back you have the burst alert telescope which detects the gamma rays from the gamma-ray burst. And here, on the left, it’s the X-ray telescope. When Swift detects a burst, it slews 1 the whole spacecraft around and points these narrow afield high resolution telescopes at that patch in the sky.”
When you look at the image of this gamma-ray burst, what you actually see is a very faint red blob which is the afterglows that gradually fades away, and the reason for that is because it is incredibly far away.
To see the burst at all, it must have been produced by a massive event. “What we think gamma-ray burst formed by? It’s the final collapse 2 of a very massive star, perhaps 20 or so times the massive star. And they run from a nuclear fuel in the core, they collapse, and in the center they form a black hole. And the matter raining onto this black hole produces a powerful jet which appears with the star, and this expel potentially in two opposite directions.”
This is an incredibly exciting way to do astronomy, because obviously you have to chase this burst in real time. So every time your phone goes to alert, you can find the gamma-ray burst with the surprising stuff for you.