Sometimes, a star is near a black hole, but not close enough to get sucked in. The black hole and the star pull on each other and orbit around each other. So if a space scientist sees a star circling around something they can't see, this can tell them where a black hole is hiding.
有时，一颗恒星靠近黑洞，但还没有近到被吸进去。黑洞和恒星相互吸引并绕对方运行。因此，如果太空科学家看到一颗恒星围绕着他们看不见的东西旋转，这可以告诉他们黑洞的藏身之处。
Black holes are also thought to send out streams of X-rays, which are a kind of energy ray, similar to light. We can't see X-rays ourselves, but we have telescopes that can detect them. So this is another clue that can show where in space black holes are.
黑洞也被认为会发出x射线流，这是一种类似于光的能量射线。我们自己看不见x射线，但我们有望远镜可以探测到它们。所以这是另一条线索，可以显示黑洞在太空中的位置。
Naming black holes黑洞的命名
When space scientists find something that looks like a black hole, they mark it on a map of the sky and give it a name. These names are made up of letters and numbers, which tell other space scientists where the black hole can be found.
Black holes are often named after the constellations, or star patterns, that are close to them in the sky. For example, there is a black hole among the stars of Cygnus, the swan. This black hole has been named Cygnus X-1.
当太空科学家发现一个看起来像黑洞的东西时，他们会在天空地图上标记它，并给它起个名字。这些名字由字母和数字组成，告诉其他太空科学家黑洞的位置。
黑洞通常以天空中离它们较近的星座或恒星模式命名。例如，在天鹅座的恒星中有一个黑洞，天鹅。这个黑洞被命名为天鹅座X-1。
