英语听力:自然百科 穿越银河系的旅行 Through Milky Way—3(在线收听

 “Now, of course, I can't show you a picture of the galaxy on our screen. We can't fly above the galaxy and take a picture of it, and show you. We're stuck in the disc of the galaxy, but we can still image it from the ground, in fact, this image is a picture of our galaxy, the Milky Way, taken from Earth.”

 
This is one of the most detailed images of our galaxy ever created. It's made from 800 million pixels contained in over 1,000 individual photographs taken from the darkest places on earth.
 
The photos have been painstakingly stitched together to create this breathtaking vista. But as impressive as it is, it's only part of the picture. 
 
“It's something like a pizza and if you were in the pizza, if you were pepperoni, your view would not be a very clear one of what the whole story was. In the same way, we don't see the whole reach of the Milky Way.
 
What astronomers really need is a bird's eye view. 
 
“You would need to get out of the Milky Way to really see what it looks like. We don't have a way to do that, but we can look at other galaxies and see what they look like.”
 
Hubble can provide us with exquisitely detailed images of nearby galaxies, like Messier 74. It's over 13 million light-years away. But that still makes it one of our nearest neighbors. Its structure is impressively clear. A beautiful spiral galaxy with its stars contained in large arms sweeping out from a bright core.
 
“This is an example of a galaxy that astronomers think looks a lot like our galaxy, the Milky Way. This is a great representation of our own star city. In the central region, we have the downtown. This is the bulge, this bright spot in the middle. And from that, we see spiraling out these arms, his beautiful spiral structures we see in this galaxy.”
 
  原文地址:http://www.tingroom.com/lesson/zrbaike/2011/260143.html