Galaxy NGC 1365's supermassive black hole spins at nearly the speed of light
Black holes are one of the universe's greatest space mysteries. The only concrete information we’ve had on them is that they can absorb all manner of matter and that you really, really don’t want to get sucked into one.
Now scientists say that they have conclusively measured the rate at which a supermassive black hole spins for the first time ever. European Space Agency and NASA scientists teamed up to discover that the surface of the black hole at the center of the galaxy NGC 1365 spins at some eye-popping rates.
Up until now, measurements on how quickly black holes spin were more like estimates because of pesky gas clouds that obscured black hole readings. This time around, scientists were finally able to truly observe a spinning black hole by teaming up NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) along with the ESA’s XMM-Newton orbiting X-ray observatory.
Astronomers used the two X-ray space observatories to see a broader range of X-ray energies emitted by the matter being sucked into the black hole. With these new observations, the scientists could see how the rotation of the black hole was the actual force distorting the surrounding energy.
"We can trace matter as it swirls into a black hole using X-rays emitted from regions very close to the black hole," NuSTAR principal investigator Fiona Harrison of the California Institute of Technology in Pasadena said in a press release. "The radiation we see is warped and distorted by the motions of particles and the black hole's incredibly strong gravity."
The scientists say the black hole is rotating so rapidly that its surface is moving at close to the speed of light, keeping it well within Einstein’s Theory of Relativity (which posits that no object can travel faster than the speed of light). The black hole is also more than two million times more massive than our own sun (the largest celestial body in our solar system). Luckily for us, this black hole resides in a galaxy 60 million light years from Earth.
NASA scientists say that these findings will help them verify previous measurements of other black hole spin rates. Hopefully, this is just the first step towards cracking the enigma of black hole science.
Story edited July 26, 2013 to clarify that, according to the Harvard-Smithsonian Center for Astrophysics, the black hole a the center of NGC 1365 is spinning so rapidly that its surface is moving at close to the speed of light.