Astronomers have found what they say is a huge black hole several million times the size of the Sun that is hurtling through space near a galaxy four billion light years away.
Supermassive black holes are thought to lurk at the centre of most galaxies, including our own Milky Way. But the newly found black hole, the researchers said, may have been kicked out of its home galaxy.
They predict that there could be many such hurtling black holes out there and that the objects, moving at millions of miles per hour, would be completely invisible to telescopes. The black holes, which have so intense gravity that they can tear stars apart, requires almost unimaginable force to move one -- but "gravity waves", or ripples in the fabric of space predicted by Einstein, could "kick" black holes out of their home galaxies, said study leader Francesca Civano of the Harvard-Smithsonian Center for Astrophysics.
"It's hard to believe that a supermassive black hole weighing millions of times the mass of the sun could be moved at all, let alone kicked out of a galaxy at enormous speed," Civano was quoted as saying by the Daily Mail.
"But these new data support the idea that gravitational waves can exert an extremely powerful force. These black holes would be invisible to us because they have consumed all of the gas surrounding them after being thrown out of their home galaxy," said study co-author Laura Blecha, also of CfA.
Civano and her group have been studying a system known as CID-42, located in the middle of a galaxy about four billion light years away. They had previously spotted two distinct, compact sources of optical light in CID-42, using NASA's Hubble Space Telescope.
More optical data from the ground-based Magellan and Very Large Telescopes in Chile supplied a spectrum that suggested the two sources in CID-42 are moving apart at a speed of at least three million miles per hour.
Previous Chandra observations detected a bright X-ray source likely caused by super-heated material around one or more supermassive black holes. However, they could not distinguish whether the X-rays came from one or both of the optical sources because Chandra was not pointed directly at CID-42, giving an X-ray source that was less sharp than usual.