Evidence found for mid-sized black hole near center of Milky Way

September 5, 2017 by Bob Yirka, Phys.org report
Credit: CC0 Public Domain

(Phys.org)—A team of researchers with Keio University in Japan has found evidence of a mid-sized black hole near the center of the Milky Way galaxy. In their paper published in the journal Nature Astronomy, the group describes their study of a gas cloud cluster near the center of our galaxy and why they believe it offers evidence of a mid-sized black hole.

Over the years, scientists have found a lot of physical evidence of large and small black holes, but very little evidence for those in the mid-size range. This has led to an intense search, which until now, has come up mostly empty—mid-size black holes are exceedingly difficult to spot.

The team reports that last year, they discovered a near the of the Milky Way that appeared to behave in odd ways—some of the gasses were moving faster than others. The cloud, named CO-0.40-0.22, was intriguing because not only did it represent the possibility of finding an intermediate black hole, but it could also explain how massive black holes come to exist at the centers of galaxies, such as our own Milky way.

The team originally spotted the gas cloud using the Nobeyama radio telescope in Japan—but to learn more about what they had found required something bigger, so they ventured to Chile, where they gained access to the Atacama Large Millimeter/submillimeter Array. The researchers found that there was a dense part of the gas cloud near its center that also showed varying velocities. Better yet, just next to the clump, they found a source of radio waves that was very similar to those generated from the giant black hole at the center of Milky Way, but 500 times weaker. The two findings together suggested very strongly the presence of a mid-sized black hole. To add further evidence, the researchers built a simulation of the gas cloud and its characteristics, particularly the gas velocities, and found that it, too, pointed to a mid-sized black hole.

These findings offer strong of a mid-sized black hole, though it is not clear how it might have come to that location. But as more research is done and the find is confirmed, the mid-sized black hole could explain how giant black holes at the centers of galaxies are formed—by swallowing nearby mid-sized , perhaps.

Explore further: A possible explanation for why no intermediate sized black holes have been found

More information: Tomoharu Oka et al. Millimetre-wave emission from an intermediate-mass black hole candidate in the Milky Way, Nature Astronomy (2017). DOI: 10.1038/s41550-017-0224-z

Abstract
It is widely accepted that black holes with masses greater than a million solar masses (M⊙) lurk at the centres of massive galaxies. The origins of such 'supermassive' black holes (SMBHs) remain unknown, although those of stellar-mass black holes are well understood. One possible scenario is that intermediate-mass black holes (IMBHs), which are formed by the runaway coalescence of stars in young compact star clusters, merge at the centre of a galaxy to form a SMBH3. Although many candidates for IMBHs have been proposed, none is accepted as definitive. Recently, we discovered a peculiar molecular cloud, CO–0.40–0.22, with an extremely broad velocity width, near the centre of our Milky Way galaxy. Based on the careful analysis of gas kinematics, we concluded that a compact object with a mass of about 105M⊙ is lurking in this cloud. Here we report the detection of a point-like continuum source as well as a compact gas clump near the centre of CO–0.40–0.22. This point-like continuum source (CO–0.40–0.22*) has a wide-band spectrum consistent with 1/500 of the Galactic SMBH (Sgr A*) in luminosity. Numerical simulations around a point-like massive object reproduce the kinematics of dense molecular gas well, which suggests that CO–0.40–0.22* is one of the most promising candidates for an intermediate-mass black hole.

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19 comments

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physman
5 / 5 (3) Sep 05, 2017
cool
Chris_Reeve
Sep 05, 2017
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Da Schneib
4.3 / 5 (6) Sep 05, 2017
The article is open access. Have fun.

This object is some 125 light years from Sgr A*, so it won't be merging within our lifetimes, but we will be able to get its trajectory fairly shortly (a decade or less) and that will be very interesting. This is actually quite interesting because this is the first one we've found in the Milky Way with strong evidence (three lines of evidence in this paper).
Chris_Reeve
Sep 05, 2017
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jonesdave
3.5 / 5 (8) Sep 05, 2017
At that point, the cloud's inherent electrodynamics takes over and gravity (and hence, the black hole) is just completely moot


Really? Please show me a paper within the last 10 years that claims such.

jonesdave
3.2 / 5 (9) Sep 05, 2017
Da Schneib, think for a second about the logic here ...


Lol. Isn't that a bit illogical, coming from somebody who still believes in Velikovskian woo?
Come on, Chris; where was Saturn 10 000 years ago, love? 20 000 years ago? You believe in physics defying woo, you burke. Do not pretend to lecture far smarter people than you on physics.Yes? Now go away, and play with the morons at Thunderdolts. That is your level. Idiot.
jonesdave
3 / 5 (8) Sep 05, 2017
For anybody who is reasonably scientifically literate, the paper is freely available here:

https://arxiv.org...7603.pdf
jonesdave
3 / 5 (8) Sep 05, 2017
Could anybody from the loony tunes garbage that is "electric universe", please explain the velocity differences? What has this got to do with CIV? Please explain. Scientifically.
jonesdave
2.8 / 5 (9) Sep 05, 2017
Da Schneib, think for a second about the logic here ...

HVC's are simply anomalous-velocity clouds which have been generally shown to exhibit CIV's for the universe's most common elements. In simple terms, that means that we have charged particles slamming into neutrals at sufficient velocities to ionize them.

What the researchers are doing is saying that since they cannot identify the cause for the cloud's velocity, that it MUST be a black hole. And why don't we see the cause? Well, because their claimed entity is not directly visible. How exactly can somebody falsify such a claim?

But, more than that,...yada yada yada.


Dear God, there is some crap written on here, but Reeve surely takes the biscuit for chief crapperer. What did you qualify in, Chris? Astrology? Homeopathy? Velikovskianism? Ever attended a science lesson, dear? No, thought not. Strewth.

Mimath224
5 / 5 (1) Sep 05, 2017
Interesting article. Yes, I can see how the inference of a mid sized BH is building here. I do hope that others will follow in the observations over greater time and more equipment. Must admit I hadn't given this type of find much thought...oh well, learn something new and I have something else to think about.
@jonesdave you mention Velikovskyism etc. While you and I might disagree with V's conclusions Velikovsky did a lot of work to form his conclusion(s). But I always feel that if someone has the integrity to 'stand up and be counted' with his/her work then that is good. Those that lack integrity often follow blindly, don't do the 'work' or prefer certain conclusions just to go against the grain, as it were. Astrology and Homeopathy are, in principle, different V's studies but this is not the place to discuss them. Ha, you made me smile with your 'Strewth'...haven't seen or used that word in ages.
Chris_Reeve
Sep 05, 2017
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Chris_Reeve
Sep 05, 2017
This comment has been removed by a moderator.
Da Schneib
3.7 / 5 (3) Sep 05, 2017
@jonesdave, the article is open access at Nature: Astronomy, and it has all the pretty graphs and stuff too. It's good to have the arXiv link, but in this case it's redundant.
yep
3 / 5 (6) Sep 06, 2017
http://physweb.bg...7096.pdf
JonesDumb the only black hole is the one in your head.
I'm still laughing at you, Garbage in garbage out felcher.
Chris_Reeve
Sep 06, 2017
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Chris_Reeve
Sep 06, 2017
This comment has been removed by a moderator.
Chris_Reeve
Sep 06, 2017
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Benni
3 / 5 (8) Sep 06, 2017
Black hole promoters would be wise to revisit the simple algebra that defines the gravitational force. There are really three compounding problems here:


@Chris,

BH Enthusiasts are the least scientifically literate who populate the Comments section here, they are also the most prolific foulmouthed name callers. They cannot prove GRAVITY fields can exist in the absence of MASS, yet they will go on the most extreme tirades when they are challenged to prove gravity is MASS DEPENDENT as dictated withIn the Einstein Field Equations.

The jonesys & schneibos have this fantasy that INFINITE GRAVITY & INFINITE DENSITY can exist inside a FINITE STELLAR MASS. The funny farm science these people have deluded themselves with is entertainingly delusional to read. They really do believe gravity can just show up out of nowhere simply by taking a GIVEN MASS & shrinking the volume of space in which it occupies, and POOF more gravity just appears from out of nowhere.
Chris_Reeve
Sep 06, 2017
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