NASA, black hole, star, TDE
Artist's illustration depicts what astronomers call a "tidal disruption event," or TDE.CXC/M. Weiss; X-ray: NASA/CXC/UNH/D. Lin et al

Astronomers have made a startling discovery that challenges the very tenets of physics as we know it! An enormous black hole has been consuming the remains of a star it ripped apart more than a decade ago. The time span between a star being ripped apart and completely devoured by a black hole is usually one year, which is why this decade-long feast has stunned astronomers.

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Scientists observing this phenomenon used a trio of X-ray telescopes: NASA's Chandra X-ray Observatory, the Swift satellite and ESA's XMM-Newton to study the black hole. This steady digestion, known as a Tidal Disruption Event (TDEs) is now being closely monitored.

As a star is ripped apart by the gravitational pull of a black hole it emits a large amount of heat — millions of degrees —  and emits X-rays that can then be mapped by telescopes.

"We have witnessed a star's spectacular and prolonged demise," said Dacheng Lin from the University of New Hampshire in Durham, New Hampshire, who led the study, according to a NASA statement.

"Dozens of Tidal Disruption Events have been detected since the 1990s, but none that remained bright for nearly as long as this one," Lin added.

The event occurred in a tiny galaxy located 1.8 billion light years away from Earth. The black hole is located in an X-ray source known as XJ1500+0154.

The XMM-Newton discovered the X-ray source on July 23, 2005 and its luminosity was found to reach its peak on June 5, 2008, when the X-rays emitted increased 100-fold, when observed by Chandra. Since 2008, it has been observed and studied on numerous occasions.  

With the help of Chandra X-ray Observatory, the accumulated data revealed that the XJ1500+0154 is situated bang in the middle of its host galaxy, where supermassive black holes are invariably located.

Another discovery revealed by the X-ray data is that the matter surrounding the black hole was found to have crossed the Eddington limit — the balance between a black holes' inward gravity pull and the outward pressure of the radiation given off by the hot gas..

"For most of the time we've been looking at this object, it has been growing rapidly," said co-author James Guillochon of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts.

"This tells us something unusual: Like a star twice as heavy as our is being fed into the black hole," Guillochon added.

This discovery led to the revelation that supermassive black holes can grow rapidly by various means, including TDE. Such rapid growth could shed light on how black holes gain masses billion times greater than the Sun's, when the universe is only around a billion years old.

"This event shows that black holes really can grow at extraordinarily high rates," said co-author Stefanie Komossa of QianNan Normal University for Nationalities in Duyun City, China.

"This may help understand how precocious black holes came to be," Komossa stated.

The researchers concluded that within a decade, the black hole's feeding supply would reduce radically, which would cause the X-ray brightness of XJ1500+0154 to dim over the next few years.