WASHINGTON, March 23 (Xinhua) -- A supermassive black hole has been found kicked out of the center of a distant galaxy by what could be the power of gravitational waves, U.S. space agency NASA said Thursday.
Although there have been several other suspected runaway black holes elsewhere, none has been confirmed so far, NASA said.
Astronomers think this object, detected by NASA's Hubble Space Telescope, is a very strong case.
Supermassive black holes usually reside in the centers of galaxies, but the newly discovered black hole, with a mass of one billion times the Sun's, was in a region far from the core of its host galaxy, known as 3C186, which was located eight billion light-years away.
"Researchers estimate that it took the equivalent energy of 100 million supernovas exploding simultaneously to jettison the black hole," NASA said in a statement.
"The most plausible explanation for this propulsive energy is that the monster object was given a kick by gravitational waves unleashed by the merger of two hefty black holes at the center of the host galaxy."
The researchers calculated that the black hole has already travelled about 35,000 light-years from the center, which is more than the distance between the Sun and the center of the Milky Way.
And it continues its flight at a speed of 7.5 million kilometres per hour, NASA said. At this speed the black hole could travel from Earth to the Moon in three minutes. That's fast enough for it escape its host galaxy in 20 million years and then roam through the universe forever.
The findings will be published in the March 30 issue of Astronomy & Astrophysics.