It’s a big day for space science. Astronomers have calculated that a massive black hole at the center of a galaxy 60 million light years away is rotating at speeds close to the speed of light.
It’s long been suspected that gigantic black holes grow larger and rotate faster as they gorge on stars, gas, dust, and matter. But, until now, there hasn’t been a precise measurement of the spin rate of a black hole until now.
While black holes are notoriously difficult to detect, the region around them gives off unique X-rays.
For several days last summer, an international team of astronomers used NASA’s NuStar telescope and the European Space Agency’s XMM-Newton orbiting X-ray satellite observatory simultaneously tracked high-energy X-rays released by a supermassive black hole at the center of a spiral galaxy called NGC 1365.
The galaxy was chosen because it is 60 million light years a way, a relatively close distance. Astronomers calculated its spin at close to the speed of light – 670 million miles per hour, The Guardian reports.
Black holes possess masses billions to billions of times that of the sun and are thought to reside at the center of every galaxy in the universe. Their defining characteristic is a super-powerful gravitational pull that not even light itself can escape. Scientists are interested in finding out the spin rates of these monster space bodies to help shed light on their growth.
According to University of Maryland astronomer Christopher Reynolds, who was not part of the research team, this is the first “unambiguous measurement of the spin rate” of a supermassive black hole.
“We are learning about some of the most exotic and powerful objects in the universe,” Reynolds told The Guardian via email. “This is cool science.” He went on to add that the new study proved there was a need for more powerful X-ray space telescopes.
All of this, of course, begs the question: How fast is the black hole at the center of our familiar Milky Way spinning?
Guido Risaliti, lead researcher at Italy’s Arcetri Astrophysical Observatory, says that a tough one to know that because our galaxy’s supermassive black hole isn’t as active as the observed one, and apart from occasional flares hardly any radiation flows from our black hole which makes it difficult to calculate its spin.
The supermassive black hole study has been published in the journal Nature.