'Seeds' of Supermassive Black Holes Discovered

astroengine writes "The very existence of intermediate black holes (IBMHs) is in dispute, but a group of astronomers of Keio University, Japan, have found the potential locations of three IMBH candidates inside previously unknown star clusters near the center of the Milky Way. Using the 10-meter Atacama Submillimeter Telescope Experiment in the Atacama Desert, Chile, and the 45-meter Nobeyama Radio Observatory in Japan, they hunted for the emissions from molecular gases associated with supernovae in star clusters — what they discovered could help evolve our view on how supermassive black holes form."

Comments

Well?

[santax]

Was it a true random seed?

Re:Well?

[bistromath007]

I don't have mod points, so I'm just going to tell you not to quit your day job. :|

Re:Well?

[santax]

I'm unemployed you insensitive clod.

I prefer ...

[PPH]

... the seedless variety.

Re:IBMH

[belthize]

Intermediate Mass Black Hole.

The summary transposed the M and B.

Really?

[jacerie]

"The very existence of intermediate black holes is in dispute..." By definition, An Intermediate-mass black hole is a black hole whose mass is significantly more than stellar black holes (ten times to several tens of times the mass of the Sun) yet far less than supermassive black holes (one million to many million times the mass of the Sun). A healthy dose of common sense and a basic understanding of gravity makes it pretty clear that any stellar black hole has the potential to become an IMBH. I appreciate the efforts to find existing IMBHs but to dispute the potential for their existence is ridiculous.

Re:Really?

[History's Coming To]

Incorrect, you're letting intuition get in the way. Space is big. Really big. And even if you collapse our entire solar system into a black hole then it would still have exactly the same mass as it always did, so from a distance nothing changes much. Yeah, there's a black hole where there used to be a star and some assorted debris, but it just keeps on cruising through space like it always did.

The chances of it reaching enough other bits of matter to gain a million times its own mass aren't very good, and the event horizon of a solar mass black hole is only 6km across, if it even hit another solar system it would have to be a slow pass or direct hit on the star, anything else would just perturb a few orbits and pass straight through.

Black holes also evaporate with time (due to Hawking radiation), the smaller they are the faster they evaporate. Our solar mass black hole will be nothing but an expanding cloud of weak black body photons unless a very unlikely series of events occurs.

Of course, they could merge with a nearby supermassive if they get caught up in it (e.g. Sag A*), but at no point in that whole story is there an Intermediate Mass Black Hole, the question stands.

Re:Really?

[Jeremy Erwin]

Unless you're in an unusually dense star cluster, sooner or later, you're going to run out of mass.

Re:Really?

[dido]

The reason astronomers seem to dispute the potential for the existence of these intermediate mass black holes is that no one has yet shown convincing evidence that they exist, nor do they have any convincing theories on how they could be formed. No star is massive enough to have collapsed into the alleged IMBH GCIRS 13E, which is supposed to be 1300 solar masses. For several smaller stellar black holes to coalesce into something like GCIRS 13E, that seems far less likely. Away from galactic cores where everything is very close together, stellar collisions are extremely rare. Collisions between black holes considerably more so. Contrary to popular perception black holes are not the all-sucking vacuum cleaners of the universe. Their gravity is not so different from the gravity of any other object, except beyond the event horizon. A stellar black hole five times the mass of our sun would have no more ability to attract things to itself with gravity than a star of five solar masses. So while black holes could collide, in interstellar space they don't do so very frequently, as much of interstellar space is empty, and as such, a few hundred of them coming together to form an IMBH of a thousand or so solar masses is extremely unlikely to say the least. In galactic cores on the other hand things are so close together that accretion of stuff into a black hole there would tend to continue until there's a supermassive black hole, not stopping at the thousand or so solar masses that IMBHs are hypothesized to be. The only other explanation for the formation of IMBHs is that they are primordial black holes created a fraction of a second into the birth of the universe, but this is even more shaky to say the least. Regardless of the explanation, the fact is observational evidence for IMBHs is disputed, and is nowhere near as conclusive as the evidence for stellar and supermassive black holes is. Granted, they could exist in principle, but if observational evidence is flimsy and the conditions necessary for creating one so unlikely then one might be justified in doubting their existence.

Re:Really?

[PPH]

But this dearth of IMBHs could help to explain some subtle interactions between gravity, dark matter and dark energy.

The classical thinking about stellar black holes having the same gravitational attraction as their parent star did might be wrong. Its possible that, once a stellar black hole has formed, local effects accelerate its scouring of nearby mass until it becomes a massive BH. So IMBHs are a transition state between small and large and don't spend much time (galactically speaking) as such. So their population is o lowe then expected.

Re:Really?

[aliquis]

Of course, they could merge with a nearby supermassive if they get caught up in it (e.g. Sag A*), but at no point in that whole story is there an Intermediate Mass Black Hole, the question stands.

http://en.wikipedia.org/wiki/Sagittarius_A*

Sagittarius A* (pronounced "Sagittarius A-star", standard abbreviation Sgr A*) is a bright and very compact astronomical radio source at the center of the Milky Way Galaxy

Much be of the intellectual kind!

"Imagine it played Britney Spears 27,000 years ago!"

Re:Really?

[jacerie]

I can't argue with anything you've pointed out and agree that the odds of a black hole with the mass of our sun ever reaching IMBH status,or even existing, is slim to none. I think the main issue I have is the broad definition of an IMBH itself. It is widely accepted that in order for a star to achieve a black hole state it must have a mass greater that three times the mass of Sol after any main sequence loss. Right there you're more than 25% to the minimum mass for an IMBH. If the IMBH tag is simply a measure of the mass of the black hole, then Cygnus X-1 weighing in at roughly 15 solar masses fits the bill nicely. As a bonus, it is already in the process of devouring its orbiting blue supergiant and being only 6100ly away it seems like a far more likely target for studying black hole growth mechanics.

Re:Really?

[buchner.johannes]

Black holes also evaporate with time (due to Hawking radiation), the smaller they are the faster they evaporate. Our solar mass black hole will be nothing but an expanding cloud of weak black body photons unless a very unlikely series of events occurs.

Hawking radiation is irrelevant -- it takes 10^61 times the age of the Universe for a 30 solar mass black hole to evaporate, and the time scales with M^3. http://casa.colorado.edu/~ajsh/hawk.html

Re:Really?

[jafiwam]

You are misinterpreting what they mean.

CANT exist, and DONT exist are very different concepts.

You are reading one, and hearing another.

I suggest a little philosophy and linquistics 101 to clear this up, it's a severe handicap when dealing with math, physics, and cosmology.

Re:IBMH

[Br00se]

Intermediate Black Masshole? Sounds racist.

Re:This research brought to you by the contrarians

[History's Coming To]

It detects radiation in the submillimetre wavelength, and it's 10m across. I've got a 0.1m hundred-nanometer setup (a basic Newtonian, small optical mirror).

Re:This research brought to you by the contrarians

[Anonymous Coward]

Should have added a disclaimer of some sort. I get the concept, I just think professional astronomers are terrible at naming things--both the things they observe and the telescopes they use to observe/image them. (The "large binocular telescope." The "very large telescope." The "extremely large telescope.") I'm still waiting for the "ludicrously large telescope."

I guess I could say I use a 0.16m 400-700 nm setup, but it seems more descriptive to say "TEC 160FL refractor" or just its informal name, "Howitzer."

incorrect

[slashmydots]

Actually, every black hole is the same size and they're quite small. I believe what they meant was mass.

Re:incorrect

[Ambitwistor]

The size of a black hole is proportional to its mass: its diameter is 6 kilometers per solar mass. You're probably confusing the size of the singularity (zero, or close to it) with the size of the black hole (the event horizon surrounding the singularity).

Re:This research brought to you by the contrarians

[NixieBunny]

I am an engineer who works on the 10-meter Heinrich Hertz Submillimeter Telescope. It's a wonderful instrument. You got a problem with that?

Re:This research brought to you by the contrarians

[Jeremy Erwin]

The Overwhelmingly Large Telescope. Alas, it was canceled.

(a diameter of 80 meters theoretically would halve allowed spectroscopic examination of earth sized planets 15 light years distant)

Re:This research brought to you by the contrarians

[History's Coming To]

I'm still waiting for the "ludicrously large telescope."

You mean for the spectral analysis of plaid?

Intuition vs educated guessing

[TapeCutter]

No argument with your points, they're all good. However, it's not just intution, it's an "educated guess" which is the same as what you are doing. TFA suggests star clusters as a possible mechanisim for forming IMBH's which changes some of the assumptions you're using, particularly about the density of gavitationally bound stars in a given volume of space.

For an old fart like me it doesn't seem that long ago when scientists were insisting black holes of ANY size were no more than a "mathematical curiosity". We still haven't directly observed a black hole but very few people doubt their existance. I don't know that our instruments are up to the task of taking an acurate survey for the purpose counting and weighing black holes within out galaxy, let alone the universe.

Re:Intuition vs educated guessing

[History's Coming To]

Sgr A* (thanks for the correction above!) was the first thing that convinced me that black holes probably exist. The orbits of the stars in the region suggest something that is either dense enough to be a black hole or something equally exotic and as-yet unknown (e.g. not a boring old neutron star). And I'm only a 30-something year old fart ;)

My main point was that while there is a good mechanism for solar mass black holes (or a couple of magnitudes thereof) through standard stellar evolution, and there is good evidence for supermassive black holes (e.g. Sgr A*), but not much for anything inbetween, and the idea of "small black holes getting supermassive by sucking in everything around them" isn't as intuitive or even as likely as it sounds on the face of it, so whether they exist and what the production mechanism is is still up for grabs. Supermassive black holes could have been created pretty much as they are very early in the Universe's evolution, the small ones may be created by a different mechanism (stellar collapse), and they might have very little in common when it comes to origin.

Re:Intuition vs educated guessing

[TapeCutter]

so whether they exist and what the production mechanism is is still up for grabs

Agree. Also agree that orbiting stars are convincing evidence, whereas x-ray point sources are just likely targets. I also think the origin of SMBH is not well understood, but until someone comes up with a more convincing alternative I will stick with ammalgamation as the most likely origin. Perhaps the demographics of black holes changes as the universe evolves, but finding likely targets may be difficult since the x-rays come from the accretion disk, so their strength is not a good indicator of mass. If we do find one, it will likely help us figure out how to find more.

Re:This research brought to you by the contrarians

[DrVxD]

You mean for the spectral analysis of plaid?

... or plaid-nets... (I'll get me coat)