TED演讲:从遥远的星系中我们可以学到什么(1)
Here are some images of clusters of galaxies. 这是一些星团的照片。 They're exactly what they sound like. 正如听上去一样。 They are these huge collections of galaxies, 它们是一堆星系, bound together by their mutual gravity. 由于互相的引力而吸引在一起。 So most of the points that you see on the screen are not individual stars, 你在屏幕上看到的大部分点,不是单独的恒星, bu...