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Mystery of the spinning Back Hole unraveled
High-speed spinning Black Hole! That's the latest from the amazing world of scientific discoveries.
BY OUR CORRESPONDENT
November 22, 2006
Astronomers have stumbled upon a fast spinning phenomenon which is believed to be smashing all laws of rotation.The GRS1915+105 Black Hole has been found to be spinning more than 950 times every
second.
Einstein’s General Theory of Relativity had brought to light the very existence of black holes. According to the theory, when any mass, such as a star, becomes more compact than a certain limit, its own gravity becomes so strong that the object collapses to a singular point, to be a black hole.
A team from the Center for Astrophysics has now measured a stellar-mass black hole spinning so rapidly, thereby pushing the predicted speed limit for rotation. According to astronomers in the team, this regime of gravity is as far from direct experience and knowing as the subatomic world itself.
Applying a technique to measure spin developed jointly by McClintock and Indian-born CfA astrophysicist Ramesh Narayan, the team used NASA’s Rossi X-ray Timing Explorer satellite data to provide the most direct determination yet of black hole spin. The astrophysicists under took research studies to pinpoint accurate values for the spin rate GRS1915+105, which has a spin that is between 82 per cent and 100 per cent of the theoretical maximum value.
This finding is expected to influence research on black holes emit jets, modeling possible sources of gamma-ray bursts, and the detection of gravitational waves. Astronomers describe a black hole by just two numbers that specify its mass and how rapidly it is rotating. Significantly, until now there had been no credible estimate of spin for any black hole.
A black hole’s gravity is so strong that, as the black hole spins, it drags the surrounding space along. The edge of this spinning hole is called the event horizon. Any material crossing the event horizon is pulled into the black hole. The spin frequency has been measured as the rate at which space-time is spinning, or is being dragged, right at the black hole’s event horizon.
According to reports, the high-speed black hole, GRS 1915, is the most massive of the 20 X-ray binary black holes for which masses are presently known, weighing about 14 times as much as the Sun. It is well known for unique properties such as ejecting jets of matter at nearly the speed of light and rapid variations in its X-ray emission.
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