New Delhi: Gravity-pulling black holes in the universe are in abundance. Each small patch of sky that contains distant galaxies also consist of a supermassive black hole and millions of stellar-mass black holes.
Now, an extremely luminous, variable X-ray source located outside the center of its parent galaxy has astronomers hooked, who feel that it could be a wandering black hole that belongs to a small galaxy, but fell into a large one.
The astronomers used NASA’s Chandra X-ray Observatory and ESA’s XMM-Newton X-ray observatory to discover this source.
There is also evidence for the existence of so-called intermediate mass black holes, which have lower masses ranging between about 100 and 100,000 times that of the sun, and astronomers are of the belief that supermassive black holes, with some 100,000 to 10 billion times the sun’s mass, are in the centers of most galaxies.
As per NASA, a new study reports the discovery of one of these “wandering” black holes toward the edge of the lenticular galaxy SDSS J141711.07+522540.8 (or, GJ1417+52 for short), which is located about 4.5 billion light years from Earth. This object, referred to as XJ1417+52, was discovered during long observations of a special region, the so-called Extended Groth Strip, with XMM-Newton and Chandra data obtained between 2000 and 2002. Its extreme brightness makes it likely that it is a black hole with a mass estimated to be about 100,000 times that of the sun, assuming that the radiation force on surrounding matter equals the gravitational force.
Releasing an image, the US space agency explains that the main panel of this graphic has a wide-field, optical light image from the Hubble Space Telescope. The black hole and its host galaxy are located within the box in the upper left. The inset on the left contains Hubble’s close-up view of GJ1417+52. Within this inset the circle shows a point-like source on the northern outskirts of the galaxy that may be associated with XJ1417+52.
The inset on the right is Chandra’s X-ray image of XJ1417+52 in purple, covering the same region as the Hubble close-up. This is a point source, with no evidence seen for extended X-ray emission.
At its peak XJ1417+52 is about ten times more luminous than the brightest X-ray source ever seen for a wandering black hole. It is also about 10 times more distant than the previous record holder for a wandering black hole.
The bright X-ray emission from this type of black hole comes from material falling toward it. The X-rays from XJ1417+52 reached peak brightness in X-rays between 2000 and 2002.
The authors theorize that the X-ray outburst seen in 2000 and 2002 occurred when a star passed too close to the black hole and was torn apart by tidal forces. Some of the gaseous debris would have been heated and become bright in X-rays as it fell towards the black hole, causing the spike in emission, NASA reported.