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Black Hole Found That Takes Up 14% of Its Galaxy's Mass

Soulskill posted about a year ago | from the fat-guy-little-coat dept.

Space 65

An anonymous reader sent word that astronomers have discovered an absolutely enormous black hole residing in a galaxy that seems too small for it. In a new study (PDF), researchers looked at galaxy NGC 1277 and found that its central black hole weighed in at roughly 17 billion solar masses. Quoting Phil Plait: "The problem is, that’s far more massive than the central bulge of NGC 1277 would suggest the black hole should be. It’s well over half the total mass of the bulge! In fact, the entire mass of the galaxy is about 120 billion solar masses, which means the black hole at its heart is 14 percent of the total galaxy’s mass; compare that to the Milky Way’s black hole mass of 0.01 percent and you’ll see why astronomers were shocked."

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65 comments

Well, in fairness .... (1)

gstoddart (321705) | about a year ago | (#42146955)

In fairness, it used to be a much bigger galaxy. Just wait for the x-ray/gamma ray belch which will come just before it decides to take a nap.

Re:Well, in fairness .... (2)

noh8rz9 (2716595) | about a year ago | (#42147701)

it's the borg cube, going around and assimilating the galaxy. it's already 14% complete.

Re:Well, in fairness .... (1)

Jeremiah Cornelius (137) | about a year ago | (#42147809)

Fourteen percent?

Occupy the Milky Way. Wake me as it gets to 99%. :-)

Re:Well, in fairness .... (1)

Paracelcus (151056) | about a year ago | (#42148319)

More than likely everything there is extinct by the time it gets that far!

So astronomers have finally found CowboyNeal! (1)

sconeu (64226) | about a year ago | (#42147023)

n/t

Let's call it... (-1, Troll)

hawks5999 (588198) | about a year ago | (#42147031)

The Government. :)

Re:Let's call it... (0)

Anonymous Coward | about a year ago | (#42147083)

The Government. :)

Umm, it still has to grow a bit more.

And I don't see it spending like a drunken sailor with a license to counterfeit money.

Re:Let's call it... (2)

SJHillman (1966756) | about a year ago | (#42147217)

You don't need a license to counterfeit money. Print money, sure, but not to counterfeit money.

News! (-1)

Anonymous Coward | about a year ago | (#42147043)

This was in my local paper a week ago, is this supposed to be 'news'?

Re:News! (5, Funny)

Anonymous Coward | about a year ago | (#42147111)

This was in my local paper a week ago, is this supposed to be 'news'?

No, the news is that somebody is still reading a newspaper in 2012.

Missing from the summary (4, Interesting)

mcgrew (92797) | about a year ago | (#42147053)

It's the largest black hole they've yet found, if the article I saw yesterday is correct.

Re:Missing from the summary (-1)

Anonymous Coward | about a year ago | (#42147159)

It's the largest black hole they've yet found, if the article I saw yesterday is correct.

Nah, Washington, DC is.

The place were money disappears and economies go to die.

Re:Missing from the summary (2, Informative)

Bengie (1121981) | about a year ago | (#42147845)

21b solar masses http://en.wikipedia.org/wiki/NGC_4889 [wikipedia.org]

Re:Missing from the summary (0)

Anonymous Coward | about a year and a half ago | (#42150865)

hmm... all this suggests to me that the mass of a black hole at a galaxy's center is related to the total mass of the galaxy it's in, so if you know the mass of one you can calculate the mass of the other

It might be easier to study since it's so big (3, Interesting)

voislav98 (1004117) | about a year ago | (#42147221)

I wonder if, with a black hole as large and relatively less shielded, you can look for some evidence of relativistic effects around it.

That's not a galaxy... (4, Interesting)

idontgno (624372) | about a year ago | (#42147229)

that's an accretion disc [wikipedia.org] .

Re:That's not a galaxy... (3, Funny)

dkleinsc (563838) | about a year ago | (#42148623)

That's not a galaxy, that's yo momma!

Re:That's not a galaxy... (2)

melikamp (631205) | about a year and a half ago | (#42152215)

Yo momma is so fat, she has her own exact solution of the field equations.

Re:That's not a galaxy... (1)

oodaloop (1229816) | about a year ago | (#42149225)

I thought you were going to tell us it's a space station.

Re:That's not a galaxy... (1)

turbidostato (878842) | about a year ago | (#42149657)

"I thought you were going to tell us it's a space station."

Well, we know for a stater that's no moon.

This is what happens (2)

stox (131684) | about a year ago | (#42147243)

when you let the Walton Family take over a galaxy.

stripped (1)

WillgasM (1646719) | about a year ago | (#42147265)

maybe most of the rest of the mass was stripped by some sort of galactic near-collision.

Re:stripped (3, Informative)

RKThoadan (89437) | about a year ago | (#42147625)

According to the arxiv pdf (http://arxiv.org/pdf/1211.6429.pdf) there is no strong evidence of it being stripped. Page 1, last paragraph on the right.

Re:stripped (3, Funny)

Genda (560240) | about a year ago | (#42148861)

I would think it more likely that a supermassive blackhole was ejected by a galactic collision and landed in a dwarf galaxy where its living out its retirement. Hhhmmm, sounds vaguely like the Mel Gibson story...

Visualization of how large NGC 1277 (5, Interesting)

rminsk (831757) | about a year ago | (#42147275)

Re: Visualization of how large NGC 1277 (3, Interesting)

Baloroth (2370816) | about a year ago | (#42147581)

And, interestingly enough, given the mass and size of the hole, air at sea level is about 19 times more dense than the black hole is. Black holes are just strange.

Re: Visualization of how large NGC 1277 (0)

Anonymous Coward | about a year ago | (#42147733)

No, not really. Density, or more accurately average density, is not important*. The total mass is.

* True, if something is dense enough, it will collapse to a black hole. However you are using the event horizon as a kind of arbitrary volume to calculate its density. With a black hole this large, you wouldn't even notice it when you crossed the event horizon. Try using a smaller volume and re-run your calculation.

Re: Visualization of how large NGC 1277 (1)

Anonymous Coward | about a year ago | (#42147961)

So use the mass of the universe and calculate the size of the blackhole using known physics. It would be about the size of observable universe.

http://en.wikipedia.org/wiki/Schwarzschild_radius [wikipedia.org]

Makes you think.

Re: Visualization of how large NGC 1277 (2)

ceoyoyo (59147) | about a year ago | (#42149085)

It's not quite that simple. The usual relativistic treatment of black holes seems to use a point source simplification (like you do with Newtonian gravity in high school). All the mass is assumed to be concentrated in the singularity, at the centre of the black hole. If that's the case then you're correct - the black hole consists of empty space with a point of infinite density at the middle.

But how exactly do you achieve that? The event horizon, among other things, is where time stops from the perspective of an outside observer. So from that perspective all the matter falling into a black hole slows down as it falls inward, taking an infinite amount of time to get to the horizon itself. It seems you can't cross the event horizon even if you wanted to. But if you keep dropping matter towards a black hole the event horizon will grow outwards. This must lead to a distribution of "frozen" matter throughout the volume of the black hole, which would make the GP's observation not so arbitrary after all.

I'm speculating, so if I've made an error I'd be interested to hear what it is.

Re: Visualization of how large NGC 1277 (3, Informative)

Chris Burke (6130) | about a year ago | (#42148541)

Well yes if you use the size of the event horizon and the mass of the black hole to calculate density then you get a low density.

But the mass is not distributed over that volume. inside the black hole the mass is actually contained in an infintesimal point, and the density is infinite. At least according to the math; it's impossible to look inside the event horizon to find out if that's really the case.

At the very least it's clear that a black hole must have density significantly higher than that of a neutron star. Saying it's less dense than the air is misleading in that respect.

Re: Visualization of how large NGC 1277 (1)

Baloroth (2370816) | about a year ago | (#42149129)

But the mass is not distributed over that volume. inside the black hole the mass is actually contained in an infintesimal point, and the density is infinite. At least according to the math;

Ah yes, but it also can't be, since time travels slower and slower the deeper you go, it would take infinite time for matter to actually reach that point. The actual matter distribution depends on a lot of things, mostly how it was formed. Presumably, there is at least a central region with density greater than a neutron star, but if the majority of the matter in the star was added later, or was otherwise distributed throughout the whole region of the black hole during or after it's formation, that matter would still (probably) not be very near the center, since time dilation would slow it's collapse into the hole to a crawl (or stop, actually, relative to us).

It's a little more complicated than that, of course, since time and space become all twisted around after you enter the black hole (forwards in time means deeper into the hole, for instance). Anyways, most of the mass distribution would depend on it's formation, which we have no clue about right now. Actually, it would take an infinite time for matter to even reach the event horizon, although I do believe the horizon could expand to swallow the matter, which would mean that matter that falls into it ends up "suspended" (so to speak) in the hole, which means if it formed by accretion of matter the density inside may well be about what is calculated. It's impossible to ever know for sure, since information about matter inside cannot escape, so we will never know the actual distribution (we can guess, but that is all).

Re: Visualization of how large NGC 1277 (0)

Anonymous Coward | about a year ago | (#42149943)

Ah yes, but it also can't be, since time travels slower and slower the deeper you go, it would take infinite time for matter to actually reach that point.

To an outside observer it looks like it takes an infinite amount of time for something to fall in. As that something falls in, light being emitted from it closer and closer to the event horizon takes longer and longer to escape the black hole. However, from the perspective of someone falling into the black hole, it takes a finite, and rather short amount of time to actually reach the center (because space time is still locally roughly flat and normal looking to someone falling in, short of slowly growing stress that pulls things apart, which can be quite small for large black holes until you are very close to the singularity, well within the event horizon).

Re: Visualization of how large NGC 1277 (1)

ceoyoyo (59147) | about a year ago | (#42149585)

The math is overly simplified. There is no realistic way the mass could be concentrated at the centre. It takes an infinitely long time for infalling mass to just reach the event horizon.

Re: Visualization of how large NGC 1277 (0)

Anonymous Coward | about a year and a half ago | (#42150137)

It looks like that way from the outside, but to someone falling in, they would disagree about it taking infinitely long to reach the center, for them and for everything before and after them.

Re: Visualization of how large NGC 1277 (4, Interesting)

turbidostato (878842) | about a year ago | (#42149763)

"But the mass is not distributed over that volume. inside the black hole the mass is actually contained in an infintesimal point"

Ahh! the old problem... equations versus reality!

All that the Einstenian equations tell us is that they don't know how to manage black holes beyond the event horizon (and that they are wrong about them because of that).

Given that the event horizon neatly divides the universe in two, it is perfectly reasonable to say that the black hole density (from the outer univese perspetive) averages its overall percieved mass by its volume.

At the very least it's clear that a black hole must have "density significantly higher than that of a neutron star."

Because?

All you can say is that *if* (a big if) black holes behave more or less like all the physics we know about, there must be something within the black hole with densities above those we can find on a neutron star because by all we "common sense" know, black holes are like neutron stars, only more so.

"Saying it's less dense than the air is misleading in that respect."

What's misleading about saying density is defined as mass against volume?

Re: Visualization of how large NGC 1277 (0)

Anonymous Coward | about a year and a half ago | (#42150113)

All that the Einstenian equations tell us is that they don't know how to manage black holes beyond the event horizon (and that they are wrong about them because of that).

Einstein's field equation and the rest of GR works just fine at the event horizon and beyond, it is only close to the singularity where there are some big questions. They could still be wrong of course, but so far nothing has suggested why it would be any different near the event horizon.

Re: Visualization of how large NGC 1277 (0)

Anonymous Coward | about a year and a half ago | (#42155983)

reasonable to say that the black hole density (from the outer univese perspetive) averages its overall percieved mass by its volume

Would it really be reasonable? The event horizon is simply a distance from the singularity where the escape velocity exceeds the speed of light, not an actual physical surface.

there must be something within the black hole with densities above those we can find on a neutron star because by all we "common sense" know, black holes are like neutron stars, only more so.

Once the neutrons are crushed by the Green Hulk of Gravity, there is no stopping the Crunch Time. Hulk crunches neutrons to a single blob of quark matter, like a plate of really hot grits. Then something wonderful happens as Hulk crushes the remaining hot grits, Plank gets to scoop Portman and the black hole is. It would be qualitatively different object from any stable intermediary form between the star and the singularity. At least this is how I understand it.

Re: Visualization of how large NGC 1277 (1)

Chris Burke (6130) | about a year and a half ago | (#42159405)

Ahh! the old problem... equations versus reality!

All that the Einstenian equations tell us is that they don't know how to manage black holes beyond the event horizon (and that they are wrong about them because of that).

Ahh, the old problem of equations versus your imagination of what reality might be. ;)

Einstein's equations work just fine inside the event horizon. It's the actual singularity itself which raises some eyebrows. And even then, we don't actually know that such a thing isn't possible in reality. But you are uncomfortable with the idea, therefore they're wrong. Got it.

At the very least it's clear that a black hole must have "density significantly higher than that of a neutron star."

Because?

Because it's required by those pesky equations.

All you can say is that *if* (a big if) black holes behave more or less like all the physics we know about

Everything said about just about anything can be presumed to have an "as long as our understanding is correct" qualifyer. And indeed our theory of gravity may be wrong. It saying something different than what you say is not a good argument for it being wrong.

What's misleading about saying density is defined as mass against volume?

Because the actual definition is mass divided by the minimum volume which fully contains the mass, not some arbitrary larger volume that you happen to find convenient. And since the behavior of a black hole requires exceedingly high density, it's doubly misleading.

This is odd... (1)

Nutria (679911) | about a year ago | (#42147409)

since just last night I watched a video on YouTube where Neil DeGrasse Tyson asserted that we've found all the matter out there, and that the missing stuff is all Dark Matter.

(I think that this [youtube.com] was it.)

Not that odd... (4, Informative)

Gunnut1124 (961311) | about a year ago | (#42147919)

This is just an example of a MaCHO [wikipedia.org] . We've theorized about them for a while. They are a strong candidate for a bulk of the dark matter we've detected. The other candidates are WIMPs [wikipedia.org] .

Re:Not that odd... (2)

CTachyon (412849) | about a year and a half ago | (#42151211)

This is just an example of a MaCHO [wikipedia.org] . We've theorized about them for a while. They are a strong candidate for a bulk of the dark matter we've detected. The other candidates are WIMPs [wikipedia.org] .

Uh, no. MaCHOs were supposed to be Jupiter-size to brown dwarf-size lumps of mass, careening through galaxies without being associated with stars or other luminous matter. A black hole *can* count as a MaCHO *if* it has no accretion disk, but we think most black holes have accretion disks and therefore emit X-rays (and thus don't count as dark matter). This black hole is firmly in the not-a-MaCHO category; for that matter, what we today know about Big Bang baryogenesis pretty strongly rules out MaCHOs being the dominant type of dark matter, so they've mostly fallen by the wayside in modern cosmological thinking.

Re:This is odd... (2)

Anonymous Coward | about a year ago | (#42148413)

There are actually two kinds of missing matter at this point. Evidence based on things from the Big Bang like the cosmic microwave background and relative abundance of light elements gives us an idea what portion of the mass in the universe would be made up from baryonic matter (things like protons and neutrons, so pretty much anything made of atoms), and then there is a large portion of mass that needs to be made up of something else, that is what gets called dark matter. Of the portion we think that is baryonic matter, we have not observed enough material to account for that portion yet either. So it is expected, that if the those proportions are correct, that there is still a lot of regular mundane matter to be found out in the universe that without cutting into the dark matter portion. Black holes would be grouped with the baryonic stuff because it would get most of its mass from infalling regular matter (and if not, then it wouldn't really change much anyways).

There actually was and still are some searches for rogue or otherwise previously unobserved black holes around that would account for some of the missing matter. At one point, it was thought that the missing matter could have all been black holes (i.e. before they realized we need to find non-baryonic matter), and is when the MaCHo vs. WIMP debate was going on. But searches provided some upper bounds on the numbers black holes there can be roving around the galaxy, and they wouldn't be enough to account for a significant chunk of the missing matter anyway.

Re:This is odd... (1)

Chris Burke (6130) | about a year ago | (#42148785)

If you think that he intended to say that we have literally seen every object in the universe made of normal matter, then you didn't think enough.

Re:This is odd... (1)

Nutria (679911) | about a year ago | (#42149919)

That's sure what it sounded like, and to me it sounded really, really wrong.

collision (0)

Anonymous Coward | about a year ago | (#42147577)

Is there evidence of a collision with another galaxy?

I think i need help... (0)

Anonymous Coward | about a year ago | (#42147619)

Reading headline, thinking, wow, Apple want's 14% of Samsungs revenue...

Plastic Beads (0)

Anonymous Coward | about a year ago | (#42147703)

The scientists also discovered that the Black Hole is formed by billions of small plastic beads. These are the same type of beads which were recently found on Mars!

Wow, man (1)

geoffball (1195685) | about a year ago | (#42147865)

Somebody sure stashed a lot of weed in that Black Hole. I'm hungry man, let's eat a couple stars.

Obvious Explanation (1)

Anonymous Coward | about a year ago | (#42148653)

Someone's been playing too much Katamari.

Meanwhile... (0)

Trailer Trash (60756) | about a year ago | (#42149251)

We have a black hole in DC that accounts for 20 something % of our economic mass...

Oprah Winfrey? (0)

Anonymous Coward | about a year ago | (#42149389)

Oprah Winfrey?

It's the Tardis. (0)

Anonymous Coward | about a year and a half ago | (#42150991)

Nuff said.

still waiting for 1 trillion+ solar masses... (3, Interesting)

PJ6 (1151747) | about a year and a half ago | (#42151109)

I read (I think it was in 'death by black hole') that the more massive the black hole, the less gravity you experience at the event horizon. For a 1 trillion mass black hole, supposedly it would only have 10g at its event horizon. For still greater masses, you could have 1g, something reasonable for both a human and a spaceship to deal with... in theory, you could hover a ship with a person in it at the very boundary of such an event horizon... how sharp would this boundary be? I'd lower a string to see where and how it gets clipped.

Re:still waiting for 1 trillion+ solar masses... (0)

Anonymous Coward | about a year and a half ago | (#42152019)

I'd lower a string to see where and how it gets clipped.

The string would pull you in.

Re:still waiting for 1 trillion+ solar masses... (0)

Anonymous Coward | about a year and a half ago | (#42152931)

Maintaining a stationary position above a non-rotating black hole requires more and more force, approaching infinity at the event horizon, even if the acceleration inward looks like it should be really small (for more technical detail, look up the difference between "proper acceleration" and "coordinate acceleration"). Hence, lowering a rope into a black hole of any size, if done slowly, would cause it to break at some point before the event horizon depending on the particular strength of material.

The main difference between a small and large black hole is the amount of stretching experienced by someone falling into it (hence not stationary like in the case of lowering a rope). If gradients in the gravitational field are small enough, such as with a large black hole, a person falling would not notice anything special about the event horizon (and even if gradients were large, there would be nothing particularly special about the point you fall past the event horizon).

Re:still waiting for 1 trillion+ solar masses... (0)

Anonymous Coward | about a year and a half ago | (#42153317)

If gradients in the gravitational field are small enough, such as with a large black hole, a person falling would not notice anything special about the event horizon (and even if gradients were large, there would be nothing particularly special about the point you fall past the event horizon).

Note that the "not notice anything special" part assumes an ideal, static (i.e. non-evaporating) black hole. For an evaporating dark hole (i.e. a realistic one; even though large black holes currently cannot lose mass due to the presence of the ambient cosmic microwave background radiation, this radiation will eventually be diluted enough by the expansion of the universe that even large black holes start to evaporate eventually (though extremely slowly)). For these, the infalling observer would see the black hole shrink in front of him. While the life-time of the black hole is extremely long for a far-away observer, it is actually very short in the reference frame of an infalling observer - in fact it would be the same as the time it takes him to fall in, so the moment he falls through the horizon would coincide with the moment the hole disappears, by which time he would have been exposed to strong tidal forces after all.

Re:still waiting for 1 trillion+ solar masses... (0)

Anonymous Coward | about a year and a half ago | (#42155461)

You seem to have that backwards. For an infalling frame of reference, the time it takes to reach the center of the black hole is very short, even though it looks like they are taking an infinite time to fall in from an outside observer. In that short about of time, the evaporation would be completely insignificant for any black hole large enough to actually fall into without enormous amounts of stretching before reaching the horizon.

Re:still waiting for 1 trillion+ solar masses... (0)

Anonymous Coward | about a year and a half ago | (#42155629)

Same AC replying to myself, as I forgot the second half of my post...

Besides the time being rather short in the frame of a person falling into a black hole, and hence very little exposure to Hawking radiation, the person hovering over the event horizon would be the one experiencing a lot of Hawking radiation. This fits in with the nice correspondence between Hawking radiation and the Unruh effect, where local acceleration causes black body radiation to appear in front of you. The more local acceleration there is, the more black body radiation seen, and since the local acceleration goes to infinity the closer someone gets to the event horizon for someone trying to remain stationary, the faster it seems the black hole is evaporating, which corresponds to time in their frame being much slower than an observer far away from the black hole. An infalling observer would pass through this region with none of this effect though, since if they are in free-fall, there is no local acceleration and their frame is locally equivalent to one not near a black hole.

oh really? (1)

slashmydots (2189826) | about a year and a half ago | (#42152225)

And yet we calculated dark matter into existence with 100% accuracy, I'm sure.

Something I've always wondered... (1)

wonkey_monkey (2592601) | about a year and a half ago | (#42153401)

Do physicists know for sure that there is a singularity at the heart of a black hole? Couldn't it just be something extremely (but not infinitely) dense?

Re:Something I've always wondered... (0)

Anonymous Coward | about a year and a half ago | (#42154037)

What the hell does everyone have against point singularities? They exist, get over it!

Re:Something I've always wondered... (0)

Anonymous Coward | about a year and a half ago | (#42155779)

Most people on the internet might complain about the uncertainty principle or throw something else together (enough arm chair physicists seem to be make judgements based solely on whether they like a theory or not...). A physicist would probably take issue with the idea of a singularity because we are not sure how gravity behaves on such a small spacial scale, because at some point it would depend on what theory of quantum gravity the universe actually follows. Some such theories allow for singularities, others do not, having some other process take over when the matter compresses to some small size. Also, GR gets kind of messy around the singularity of a rotating black hole, which is ring shaped, not a point.
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