translation.en: And these stars have compressed down to maybe something like 12, 15 miles wide, and they are black holes. And they are gobbling up everything around them, including light, which is why we can't see them.
translation.zh: 这些恒星压缩成直径大概12，或15英里的物质， 这就是黑洞。它们能吞噬周围的任何物质， 甚至包括光，这就是为什么我们看不到它们。