X-ray telescopes find evidence for wandering black hole

X-ray Telescopes Find Evidence for Wandering Black Hole
Credit: X-ray: NASA/CXC/UNH/D.Lin et al; Optical: NASA/STScI

Astronomers have used NASA's Chandra X-ray Observatory and ESA's XMM-Newton X-ray observatory to discover an extremely luminous, variable X-ray source located outside the center of its parent galaxy. This peculiar object could be a wandering black hole that came from a small galaxy falling into a larger one.

Astronomers think that , with some 100,000 to 10 billion times the Sun's mass, are in the centers of most galaxies. 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.

Both of these types of objects may be found away from the center of a galaxy following a collision and merger with another galaxy containing a . As the stars, gas and dust from the second galaxy move through the first one, its black hole would move with it.

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.

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.

The Chandra and XMM-Newton observations show the X-ray output of XJ1417+52 is so high that astronomers classify this object as a "hyper-luminous X-ray source" (HLX). These are objects that are 10,000 to 100,000 times more luminous in X-rays than stellar , and 10 to 100 times more powerful than ultraluminous X-ray sources, or ULXs.

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 source was not detected in later Chandra and XMM observations obtained in 2005, 2014 and 2015. Overall, the X-ray brightness of the source has declined by at least a factor of 14 between 2000 and 2015.

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.

The location and brightness of the optical source in the Hubble image that may be associated with XJ1417+52 suggest that the black hole could have originally belonged to a small galaxy that plowed into the larger GJ1417+52 galaxy, stripping away most of the galaxy's stars but leaving behind the black hole and its surrounding stars at the center of the small galaxy. If this idea is correct the surrounding stars are what is seen in the Hubble image.

A paper by Dacheng Lin (University of New Hampshire) and colleagues describing this result appears in The Astrophysical Journal and is available online.

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More information: arxiv.org/abs/1603.00455
Journal information: Astrophysical Journal

Citation: X-ray telescopes find evidence for wandering black hole (2016, October 5) retrieved 21 September 2019 from https://phys.org/news/2016-10-x-ray-telescopes-evidence-black-hole.html
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Oct 05, 2016
Both of these types of objects may be found away from the center of a galaxy following a collision and merger with another galaxy containing a massive black hole. As the stars, gas and dust from the second galaxy move through the first one, its black hole would move with it.

Just another assumption by committed merger maniacs. Here is another example of a daughter galaxy growing naturally from within as it 'wanders' away from it's origin birthplace near the central core.


Remember, stars migrate outward, not inward.


And black holes lead galactic growth, not lag.


But then, I must have it all wrong since I am not so confused as astronomers.

Oct 05, 2016

Oct 06, 2016
Anybody that cares to check will realize that you have badly misrepresented all 3 of the papers you reference. Did you not read them? Or are you relying on nobody checking?

Oct 06, 2016
"Wandering Black Hole", "Naked Black Holes" "Orphaned Black Hole" ad nauseum. How much labour and roundabout way official astrophysics has to endure to avoid a simple conclusion that these are quasars ejected from the nearby galaxies. In this particular case XJ1417+52 is a quasars ejected from the lenticular galaxy SDSS J141711.07+522540.8 (or, GJ1417+52 for short); just as Arp said long time ago, showing direct evidence of many such cases and is being denied by the power that be, ever since!

Oct 06, 2016
NGC 4319 and Markarian 205 is a similar case, where an ejection trail or a bridge between the two objects can be seen even in the most recent Hubble picture! Official astrophysics insists that in this and all other cases that Arp and others found, ALL are accidental coincidences in the line of sight where the quasars are very far away from the galaxies and are not associated with them. http://quasar.squ...755.html

How come in this particular and similar other cases, the wandering, naked, orphaned etc. "Black holes" (in fact quasars) could be associated with the nearby galaxies? The simple truth is that if they accept Arp's reasoning, then the whole virtual edifice of Big Bang cosmology collapses to the ground!

Oct 06, 2016
astrophysics has to endure to avoid a simple conclusion that these are quasars...

Think before you write. The reason Arp's "ejected quasars" were interesting for him is because the quasars were higher redshift than the galaxy he claimed they were associated with. You've already declared the end of cosmology but haven't paid enough attention to realise there is no spectra for the ULX, only the galaxy. No redshift, no redshift controversy. You're literally making it up. The idea that quasars and ULX's have host galaxies is not controversial. Also there isn't data to say this is a quasar, you need a spectrum to see the broad lines.

Oct 06, 2016
Arp's model is dead. Standard cosmology predicted one thing about all of Arp's "ejected quasars", that the quasar was behind and that absorption lines at the redshift of the galaxy would be found in the quasar spectrum, shock and horror that's what was found.

And yes, we have solid evidence to throw out his model, in the largest survey to date (SDSS) looked at the rate of high-z QSO low-z galaxy associations and found no more than is expected at random. The HST picture doesn't demonstrate the two are connected, it only shows the universe in projection. If this effect was real it would be seen in large scale statistics, not in one or two which is consistent with coincidence.


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