Astronomer sees black hole eat star
Thursday, October 24, 2002 Posted: 10:12 AM EDT (1412 GMT)
WASHINGTON (Reuters) -- It began like a routine measurement on a quasar, a somewhat boring look at the emissions from a distant, early galaxy -- but it turned out that the graduate student was actually watching a black hole swallow part of a star.
As he looked at the spectrum of light sent out by TEX 1726+344, the student at the University of Texas at Austin, Feng Ma, realized he was seeing something extraordinary.
It looked like the quasar was ejecting a cloud of matter at a speed of 3,700 miles per second (6,000 kms per second), Ma said in a statement. "This leads me to think it's the signature of a star that's been ripped apart by the black hole's gravity."
"Half of the star's matter fell into the black hole, and the other half was ejected in a gravitational sling-shot."
Quasars are bright smears of light so distant in space and time that astronomers think they are early galaxies formed when the universe, which is expanding, was young.
They are believed to have black holes at their centers. Black holes are objects so dense that they suck in just about everything around them with their huge gravitational fields.
But usually their "victims" are ripped apart in the process, ejecting part of their matter at high speeds that create radiation that can be seen from the distant Earth.
Or at least theoretically, that is what happens. Usually astronomers have just circumstantial evidence of this, in the form of leftover stardust circling the black hole.
Ma believes he may have seen the black hole in action.
He said if the spectral measurement changes in several years, this will help prove his theory.
"If this interpretation is correct, we could see this feature in the spectrum go away in the next few years. I'd like to keep an eye on this quasar to see what happens," said Ma, who reported his findings in the Monthly Notices of the Royal Astronomical Society.
