How do you find a black hole? 如何找到黑洞？
Space scientists look for black holes using telescopes. But how do you find something so tiny and invisible in space? Each black hole has a ball-shaped area around it. Within the ball-shaped area, nothing can escape from its gravity. This area is much bigger than the black hole itself.
太空科学家用望远镜寻找黑洞。但你是如何在太空中找到如此微小且看不见的东西的呢？每个黑洞周围都有一个球形区域。在球形区域内，没有任何东西可以逃脱它的引力。这个区域比黑洞本身大得多。
Once something has passed into the ball-shaped area around a black hole, it can't be seen. But space scientists can see objects such as stars orbiting around the ball-shaped area and changing shape as they are pulled towards the black hole. The black hole's powerful gravity makes stars stretch out into a string, like a lump of modelling clay when you pull on it.
一旦有东西进入黑洞周围的球形区域，就看不见了。但是太空科学家可以看到一些物体，比如围绕这个球形区域运行的恒星，在被黑洞吸引的过程中会改变形状。黑洞强大的引力使恒星伸展成一根弦，当你拉它的时候，就像一块粘土。
As objects pass close to a black hole, its gravity may make them change direction. If they get close enough, they spiral around the black hole as they get sucked in, like water swirling down a plughole. The objects move faster and faster as they get closer to the middle. When space scientists see this “plughole effect" happening in space, it means they may have found a black hole.
当物体靠近黑洞时，黑洞的引力会使它们改变方向。如果它们离黑洞足够近，当它们被吸入黑洞时，它们就会绕着黑洞旋转，就像水沿着塞孔旋转一样。物体越靠近中间，移动速度就越快。当太空科学家看到这种“堵塞效应”在太空中发生时，这意味着他们可能发现了一个黑洞。
If you half-fill a sink with water, add glitter to the water and then pull the plug out, the glitter will spiral around the plughole, going faster and faster as it gets closer to the middle. A black hole works the same way.
如果你在水槽里放一半水，在水里加入亮晶晶，然后把塞子拔出来，亮晶晶会绕着塞子旋转，越靠近中间越快。黑洞也是如此。
