Clandestine black hole may represent new population

Clandestine black hole may represent new population
Credit: X-ray: NASA/CXC/Univ. of Alberta/B.Tetarenko et al; Optical: NASA/STScI; Radio: NSF/AUI/NRAO/Curtin Univ./J. Miller-Jones

Astronomers have combined data from NASA's Chandra X-ray Observatory, the Hubble Space Telescope and the National Science Foundation's Karl G. Jansky Very Large Array (VLA) to conclude that a peculiar source of radio waves thought to be a distant galaxy is actually a nearby binary star system containing a low-mass star and a black hole. This identification suggests there may be a vast number of black holes in our Galaxy that have gone unnoticed until now.

For about two decades, astronomers have known about an object called VLA J213002.08+120904 (VLA J2130+12 for short). Although it is close to the line of sight to the globular cluster M15, most astronomers had thought that this source of bright was probably a .

Thanks to recent distance measurements with an international network of radio telescopes, including the EVN (European Very Long Baseline Interferometry Network) telescopes, the NSF's Green Bank Telescope and Arecibo Observatory, astronomers realized that VLA J2130+12 is at a distance of 7,200 , showing that it is well within our own Milky Way galaxy and about five times closer than M15. A deep image from Chandra reveals it can only be giving off a very small amount of X-rays, while recent VLA data indicates the source remains bright in radio waves.

This new study indicates that VLA J2130+12 is a black hole a few times the mass of our Sun that is very slowly pulling in material from a companion star. At this paltry feeding rate, VLA J2130+12 was not previously flagged as a black hole since it lacks some of the telltale signs that in binaries typically display.

"Usually, we find black holes when they are pulling in lots of material. Before falling into the black hole this material gets very hot and emits brightly in X-rays," said Bailey Tetarenko of the University of Alberta, Canada, who led the study. "This one is so quiet that it's practically a stealth black hole."

This is the first time a black hole binary system outside of a globular cluster has been initially discovered while it is in such a quiet state.

Hubble observations identified VLA J2130+12 with a star having only about one-tenth to one-fifth the mass of the Sun. The observed radio brightness and the limit on the X-ray brightness from Chandra allowed the researchers to rule out other possible interpretations, such as an ultra-cool dwarf star, a neutron star, or a white dwarf pulling material away from a companion star.

Because this study only covered a very small patch of sky, the implication is that there should be many of these quiet black holes around the Milky Way. The estimates are that tens of thousands to millions of these black holes could exist within our Galaxy, about three to thousands of times as many as previous studies have suggested.

"Unless we were incredibly lucky to find one source like this in a small patch of the sky, there must be many more of these black hole binaries in our Galaxy than we used to think," said co-author Arash Bahramian, also of the University of Alberta.

There are other implications of finding that VLA J2130+12 is relatively near to us.

"Some of these undiscovered black holes could be closer to the Earth than we previously thought," said Robin Arnason, a co-author from Western University, Canada "However there's no need to worry as even these black holes would still be many light years away from Earth."

Sensitive radio and X-ray surveys covering large regions of the sky will need to be performed to uncover more of this missing population.

If, like many others, this black hole was formed in the plane of the Milky Way's disk, it would have needed a large kick at birth to launch it to its current position about 3,000 light years above the plane of the Galaxy.

These results appear in a paper in The Astrophysical Journal. NASA's Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program for NASA's Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, controls Chandra's science and flight operations.

Explore further

VLA reveals 'bashful' black hole in neighboring galaxy

More information: The first low-mass black hole X-ray binary identified in quiescence outside of a globular cluster.
Citation: Clandestine black hole may represent new population (2016, June 28) retrieved 21 August 2019 from
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User comments

Jun 28, 2016
This at a time when funding for Arecibo is on the chopping block. Very short-sighted.

Jun 28, 2016
It's not a fix for the 'Missing Mass' question, but it does potentially add a hefty population to the 'known' ledger...

Jun 28, 2016
Very interesting. Of greater interest, how did it get there?

Jun 29, 2016
Ah yes, the "dark" black hole as an ad hoc patch to what is otherwise a misunderstood interpretation of a plasma phenomena. One of these days they may realize what Hannes Alfvèn figured out 80 years ago, they could learn more about astrophysical plasmas by looking at plasmas in the lab. When they figure it out we will be able to emerge from the "dark ages" of astrophysicis.

Jun 29, 2016
You have misspelled the name of your idol !

Oh right, the little e thingy is leaning the wrong way, does that qualify for misspelled?

Otherwise your post is the usual fodder.

I know, how can I have the temerity to suggest experimentation should be part and parcel to science? Especially considering that your idol Ienstien detested laboratory experiments in favor of pure thought experiments.

Jun 30, 2016
Nice, thanks @FSC!

Jul 01, 2016
I find it particularly gratifying to see the authors giving consideration to a number of alternative types of objects, or object configurations (Accreting Neutron Star Low-Mass X-ray Binaries, Cataclysmic Variables, Magnetars, Planetary Nebula, Millisecond Pulsars, Ultracool Dwarfs), as possible candidates for the system responsible for such a high radio/X-ray flux ratio, before dismissing them as unlikely on various sound scientific grounds.

So, BH-LMXB (black hole - low mass X-ray binary) it appears to be.

It would me more gratifying if they would consider plasmoids and plasmoid ejection then some of those other fairy tales.

Jul 01, 2016
It would me more gratifying if they would consider plasmoids and plasmoid ejection then some of those other fairy tales.

Why would they consider real plasma phenomena when they can pontificate fanciful like and make one additional hoc guess after another using "maths we know from experiments we know are wrong". They prefer maths gymnastics to real science.

Jul 01, 2016
One of these days they may realize what Hannes Alfvèn figured out 80 years ago
-hannes figured it out
-& yall are acolytes of hannes
-& yall claim to be following the scientific method
why can't you post source material from peer reviewed journals demonstrating the predictability of eu?

i mean... if hannes et al figured this out and your eu cult has the answers, why isn't it predicted and demonstrated in a peer reviewed journal entry (source material, not thunderbutt-nuts)?

why haven't your cult predicted the above with demonstrations, math, models, and experimental validation?

it's not like yall haven't have time



It would me more gratifying if they would consider
how do you know they weren't ruled out due to scale, evidence etc?

can you demonstrate, with links/ref's and evidence that it wasn't considered?
or can you demonstrate with source material that the above would produce the same evidence?

Jul 03, 2016
If you took the time to learn plasmoids have been created in the laboratory since the mid to late fifties and instruments to detect them in the earth and suns atmosphere have been going into space since the seventies. We know they can emit radio, x-ray and synchrotron radiation. Scaleing is not an issue.

Jul 04, 2016
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Jul 04, 2016
Here's why scaling is an issue:

The speed of light.

We're not even talking about apples and oranges; more like cherries and watermelons.

Jul 04, 2016
If you took the time to learn plasmoids
and if you stopped reading bullsh*t and learned physics you wouldn't be an acolyte for the eu

try it... reality is actually far more interesting than delusion

Scaleing is not an issue
1- see link above: learn physics
2- see Da Schneib post
3- see ElectricBoobVerses post
4- ignorance means you didn't know something, but stupidity means you learned about reality but dismissed it for the sake of your beliefs

point being - if scaling isn't an issue, and you are correct, where is the published peer reviewed journal study?
where is the validation?

i noticed you didn't supply any links to studies: why?
if this has "been created in the laboratory since the mid to late fifties" then...

the scientific method works
the eu doesn't follow it
therefore, by definition the eu is pseudoscience

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