A certain black hole is more insatiable than expected. The P13 is a black hole along the outer edge of the NGC7793 galaxy located around 12 million light years away from the Earth. It’s very luminous compared to others of its kind but as it turns out, this has nothing to do with the black hole’s size.
P13 is eating a star faster than scientists had thought was possible, and it’s unleashing unusually bright X-ray signals that may help scientists understand a group of weird, superbright objects in deep space.
P13 is the most ravenous black holes in the universe are more like 128-pound Japanese eating champion Takeru Kobayashi than they are like hungry (and huge) sumo wrestlers. It eats the equivalent of 100 billion billion hot dogs every minute.
Researchers noticed P13 was more luminous than other black holes – when gas falls towards a black hole it gets very hot and bright. Researchers found that P13 is about a million times brighter than the sun. At first, astronomers thought it was just bigger than other black holes, astronomer Roberto Soria said:
“It was generally believed the maximum speed at which a black hole could swallow gas and produce light was tightly determined by its size. So it made sense to assume that P13 was bigger than the ordinary, less bright black holes we see in our own galaxy, the Milky Way.”
Dr. Soria said that after analyzing the mass of P13, they realized how much material the black hole was actually consuming. There is no set limit for black holes, they can consume as much gas as they want and produce more light.
In addition, Soria said P13 rotates around a supergiant ‘donor’ star, which is twenty times bigger than our own Sun. Also, P13 is a member of a select group of black holes known as ultraluminous X-ray sources.
These new findings suggest that stellar-mass black holes growing at super-Eddington rates could help explain “a majority of ultraluminous sources,” Motch said. However, some ultraluminous X-ray sources are too bright to be stellar-mass black holes, even assuming super-Eddington rates of growth, or the wavelengths of X-rays they give off are consistent with growth rates below the Eddington limit. These other ultraluminous X-ray sources “may be powered by high-mass stellar black holes up to 100 solar masses, or by intermediate-mass black holes,” Motch said.
The study “A mass of less than 15 solar masses for the black hole in an ultraluminous X-ray source” was led by University of Strasbourg’s Dr. Christian Motch.