Black Hole Spins at Nearly the Speed of Light
A superfast black hole appears to be pushing the ultimate speed limit of the universe, a new study says.
For the first time, astronomers have managed to measure the rate of spin of a supermassive black hole—and it's been clocked at 84 percent of the speed of light, or the maximum allowed by the law of physics.
"The most exciting part of this finding is the ability to test the theory of general relativity in such an extreme regime, where the gravitational field is huge, and the properties of space-time around it are completely different from the standard Newtonian case," said lead author Guido Risaliti, of the Harvard-Smithsonian Center for Astrophysics (CfA) and INAF-Arcetri Observatory in Italy. (Related: "Speedy Star Found Near Black Hole May Test Einstein Theory.")
Notorious for ripping apart and swallowing stars, supermassive black holes