The pair of black holes the set off the first detection of gravitational waves through space may have been spawned by the death of a single, massive star.
“It’s the cosmic equivalent of a pregnant woman carrying twins,” astrophysicist Avi Loeb, with the Harvard-Smithsonian Center for Astrophysics, said in a statement.
Scientists believe that when a massive star explodes, its core collapses into a black hole, which is a region so dense with matter that not even photons of light can escape from the gravitational warping of space and time.
Scientists detected a gamma ray flash on Sept. 14, 2015, just a fraction of a second after the Laser Interferometer Gravitational-wave Observatory (LIGO) picked up the first signals of gravitational waves, caused in this case by the merger of two black holes.
Gravitational waves are similar to electromagnetic radiation, such as radio, visible, light and X-rays, except that it is space itself that is waving.
Loeb believes that that gamma ray burst may be a clue that the black holes seen by LIGO were twins, born out of the destruction of a single star.
He theorizes that if the star was spinning very fast, the core may have been stretched into a dumbbell shape, and then separated into two sections, each forming a black hole.
“In order to power both the gravitational wave event and the gamma-ray burst, the twin black holes must have been born close together, with an initial separation of order the size of the Earth, and merged within minutes. The newly formed single black hole then fed on the in-falling matter, consuming up to a sun’s worth of material every second and powering jets of matter that blasted outward to create the burst,” the Harvard-Smithsonian Center for Astrophysics said in a statement.
NASA’s Fermi Gamma-ray Space Telescope discovered the gamma burst just 0.4 seconds after the LIGO gravitational waves’ detection, the center said. Both events came from the same general area of the sky.
Read more at Discovery News
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