`Supermassive' black hole rocketing through space at five million miles an hour, Nasa reveals Hubble Space Telescope image shows it being pushed around galaxy by gravitational waves eight billion light-years from Earth Black holes are the big bullies of space. They're so massive that their gravity doesn't let any light escape.The biggest black holes, called “supermassive“, weigh as much as a billion suns. Looming at the centre of seemingly every galaxy, including the Milky Way, they control the formation of stars and can deform the fabric of space-time itself. It takes a lot to push a black hole around.
But eight billion light-years from Earth, in a galaxy called 3C 186, astronomers have discovered a supermassive black hole that got kicked off its throne. Now it's rocketing through space at a speed of almost 5 million miles an hour. There's one thing that could unseat a supermassive black hole in this manner, the researchers say: gravitational waves.
First predicted by Albert Einstein more than 100 years ago, gravitational waves are ripples in space-time caused by the universe's most cataclysmic events just as concentric circles form on the surface of a pond after you toss in a heavy rock. Last year, researchers at the Laser Interferometer Gravitational-Wave Observatory (LIGO) showed that this phenomenon exists when they detected gravitational waves produced by the merger of two black holes. In a paper that will publish next week in the journal Astronomy & Astrophysics, Marco Chiaberge and his colleagues say that the weird behaviour of the black hole in galaxy 3C 186 is likely the result of gravitational waves from another pair of colliding black holes.
The roving black hole was detected in an image taken by Nasa's Hubble Space Telescope. The fuzzy splotch that was galaxy 3C 186 contained an incredibly bright spot, a quasar. This wasn't unusual: a quasar is the nucleus of a galaxy, and it's bright because of the disk of gas that surrounds the black hole at its centre.
What caught Chiaberge's eye was the quasar's location, 35,000 lightyears from the centre of its galaxy.“We were seeing something very peculiar,“ he said in a Nasa release.
Chiaberge, who works at the Space Telescope Science Institute (STScI) and Johns Hopkins University, asked fellow astronomers for their observations from a range of other instruments, including the Chandra space observatory and the Sloan Digital Sky Survey's telescope in New Mexico. The former measures X-rays, the latter specialises in detecting redshift, the stretching of light that is detected as something travels through space. Their observations confirmed the Hubble finding. They also helped pin down the black hole's mass (equal to that of a billion suns) and the speed at which the gas around it was travelling (4.7 million mph).