How do astronomers find supermassive black holes?
When a black hole is active and swallowing up lots of matter, it shines brightly and is easily detected. These quasars have properties very distinct from normal stars and galaxies, and this makes it possible to find them even at very large distances. Within the centers of nearby galaxies, where black holes are mostly dormant, we can try to “weigh” an invisible black hole by measuring the motion of stars or gas clouds orbiting it. By determining the speed of objects orbiting the center of a galaxy, we can measure the mass of a black hole even if we can’t see it directly. Q: How are you researching black holes in your laboratory? A: Unfortunately, limited research budgets and safety regulations don’t permit us to construct or study supermassive black holes in a laboratory. So we do the next best thing: We observe them with telescopes. My research group uses data from the W.M. Keck Observatory in Hawaii, Lick Observatory in California, and NASA facilities like the Hubble Space Telescope,
