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Colliding Galaxies Reveal Colossal Black Holes 134

Posted by CmdrTaco
from the duck-and-cover dept.
Matt_dk writes "New observations made with the Submillimeter Array of telescopes in Hawaii suggest that black holes — thought to exist in many, if not all, galaxies — were common even in the early Universe, when galaxies were just beginning to form. Astronomers have found two very different galaxies in the distant Universe, both with colossal black holes at their hearts, involved in a spectacular collision."
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Colliding Galaxies Reveal Colossal Black Holes

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  • by smooth wombat (796938) on Thursday October 16, 2008 @12:28PM (#25401483) Homepage Journal

    the web site has become a black hole as well.

  • by Anonymous Coward

    Pictures please!
    Or would that be considered "galaxy pron" ?

  • by IndustrialComplex (975015) on Thursday October 16, 2008 @12:38PM (#25401613)

    I don't think that discovering early black holes is all that surprising given that concentrations of matter were much greater early on.

    What I want to know, is how did the universe expand beyond its own swartzchild radius?

    • If one considers the law that matter/energy can neither be created or destroyed, the answer would have to be that the universe is just the exit point for the blackhole preceding it. And so on. You've heard of the infinite loop? ;)

      • by MBGMorden (803437)

        I'm not following you at all - matter going into a black "hole" doesn't get destroyed. There's no need for it to "come out" anywhere It's not literally a "hole" - it's just an indredibly (unfathomably) dense object.

        Technically the black "hole" in the center of our galaxy is still a little spherical ball of matter and energy just like any other object - it's just that the density is high enough that gravity starts to behave strangely close to it.

        • Exactly.

          Compress it all into a neat little ball, and at some point, that ball will go bang. Maybe a Big Bang. What do time and other dimensional characteristics look like after the event? Something like us?

          • Re: (Score:3, Insightful)

            by MBGMorden (803437)

            Compress it all into a neat little ball, and at some point, that ball will go bang.

            Actually the evidence suggests that you if you keep compressing the ball a bang becomes very unlikely. Once matter is pile onto the singularity, about the only way it seems to come back off it through Hawking Radiation, which is more of a "Little, Slow, Trickle" than a Big Bang.

          • Re: (Score:2, Interesting)

            by Xcruciate (261968)

            I have always thought that this might be the case. I think that space/time is infinite. In our little corner of this infinite void, we have our "universe" of matter and energy (galaxies, dark matter, etc.). A black hole forms and creates a singularity which sucks in matter and energy. One has to ask where that stuff goes. I surmise that the singularity just punches a hole in the fabric of space/time and dumps the matter/energy into another corner of the infinite space/time, thus creating a "big bang"

    • Re: (Score:3, Interesting)

      by pokerdad (1124121)

      What I want to know, is how did the universe expand beyond its own swartzchild radius?

      Depending on what you take the mass of the universe to be (and age too), we may not have hit it yet.

    • I know it's really easy to, after the fact, say "I knew that all along," but now it's +5 Insightfull? Guess what? Saying "that was obvious" is not how science works! There were lots of scientist who thought it was "obvious" that there would be black holes, and a lot who thought it was "obvious" that there wouldn't be; so this result, despite your dismissive attitude, is news. But even if that WEREN'T the case, it's still good science to find out for CERTAIN something we, thusfar, were only able to ASSUM
    • by JustinOpinion (1246824) on Thursday October 16, 2008 @01:13PM (#25402093)

      What I want to know, is how did the universe expand beyond its own swartzchild radius?

      It didn't.

      To compute the Schwarzschild radius [wikipedia.org] of the universe, we need to know its mass. Recent measurements suggest that the universe is flat [wikipedia.org], and so may have infinite mass. However at a minimum we can count up the mass within the observable universe [wikipedia.org]. The observable stars in the universe have a mass of ~2*10^52, but they are overwhelmed by dark matter, which brings the total mass within our observation volume to ~4*10^53 kg. So the Schwarzschild radius for the universe is:

      r = (2*G*m)/(c^2) = 2*(6.7E-11 m^3kg^-1s^-2)*(4E53 kg)/(3E8 m/s)^2 = 6E26 m = 60 billion light-years.

      Since the observable universe is ~46 billion light-years in radius, this means that the Schwarzschild radius of the universe is bigger than what we consider to be "the universe." In other words, we are well within the Schwarzschild radius, leading some people to describe the universe itself as a massive black hole that we are actually inside of.

      The universe probably has a mass larger than what we can observe, making the radius even larger than the above estimate. If the universe truly has infinite mass, then the radius is infinite. In other words, the universe may not have a Schwarzschild radius at all.

      This is also a decent description. [nasa.gov]

      • Since the observable universe is ~46 billion light-years in radius, this means that the Schwarzschild radius of the universe is bigger than what we consider to be "the universe." In other words, we are well within the Schwarzschild radius, leading some people to describe the universe itself as a massive black hole that we are actually inside of.

        Not according to the Wiki [wikipedia.org]...

        The Schwarzschild radius (sometimes historically referred to as the gravitational radius) is a characteristic radius associated with every mass. It is the radius for a given mass where, if that mass could be compressed to fit within that radius, no known force or degeneracy pressure could stop it from continuing to collapse into a gravitational singularity.

        If the universe is smaller than its Schwarzschild radius, it should collapse into a singularity. It hasn't, so it apparently isn't.

        • Give it time.
          • The universe is supposedly expanding, not collapsing.

            • The universe is supposedly expanding, not collapsing.

              What if you view it from the perspective of how objects would appear to have a redshift, if they were all accelerating toward a central point.

              Take a massive gravitational force: A
              Objects B, C, and D are arranged in a line extending from Object A. A to B is the same distance from B to C. Initially all points are at rest.

              If A were something massive, B, C, and D would all appear to have a redshift relative to each other. Although they are all accelerating

        • by JustinOpinion (1246824) on Thursday October 16, 2008 @03:59PM (#25404407)

          If the universe is smaller than its Schwarzschild radius, it should collapse into a singularity. It hasn't, so it apparently isn't.

          As mentioned here [nasa.gov], the concept of a Schwarzschild radius is one limiting case of Einstein's equations of general relativity. It is a useful concept with various rules-of-thumb, but one must be careful in applying it to all situations. In particular, the approximation breaks down, and a full treatment using the equations of general relativity is instead necessary, for "extreme" situations (like inside a black hole, during the big bang, when applied to the entire universe, etc.).

          More specifically (this site seems to explain it somewhat [ucr.edu]), the "Schwarzschild black hole" is just one solution to the equations of general relativity--it is a limiting case for nominally static matter (that is also non-rotating, spherically symmetric). Other solutions are required in other cases (e.g. the Kerr solution for rotating black holes [wikipedia.org]). The Schwarzschild solution doesn't apply to dynamic systems (e.g. rapidly expanding matter). In particular the big bang and subsequent expansion of the universe represent a different solution to the equations of GR. This solution provides for a roughly flat space but massive expansion (hence highly curved spacetime, as one would expect for such high mass-density). Our best understanding suggests that inflation [wikipedia.org] occurred (where space was expanding faster than the speed of light, although light/energy/matter/information was still constrained by c).

          In my previous post I was just pointing out that the expected size for the Schwarzschild radius is very large. However that is based on a naive application of the usual rules-of-thumb. The big bang, if you will, is extreme enough that it requires a more careful treatment. Moreover, our best data right now suggests that the universe is roughly flat and infinite (and thus with infinite or at least extremely large mass), meaning that there is probably no meaningful way to apply the "Schwarzschild radius" concept to it.

          Disclaimer: I'm not a cosmologist. Hopefully I didn't make a mistake.

      • by LionMage (318500)

        Recent measurements suggest that the universe is flat, and so may have infinite mass.

        OK, as a former physics major (got my BS in physics and then moved on to computer science for my MS), this bugs me. The Wikipedia article you cite is interesting, but about as opaque to the non-technical reader as you can make it. And I certainly take exception to the conclusion that "flat universe = infinite mass" (which conclusion I don't think even the Wikipedia article you cited supports).

        The way I always understood t

        • I certainly take exception to the conclusion that "flat universe = infinite mass"

          By "flat" I mean space has no curvature and is thus effectively Euclidean. This means (as far as I understand it), that space continues on forever in each direction. It doesn't wrap back upon itself and reconnect (which is what would happen for a curved geometry like spherical space). So "flat universe" = "infinite space." Now, if the matter density of the universe is roughly homogeneous on large scales (which it is within our Hubble volume), then every region of space has some mass. So "flat universe" + "h

    • by gnick (1211984) on Thursday October 16, 2008 @01:13PM (#25402095) Homepage

      Schwarzschild radius: [wikipedia.org]

      The Schwarzschild radius (sometimes historically referred to as the gravitational radius) is a characteristic radius associated with every mass. It is the radius for a given mass where, if that mass could be compressed to fit within that radius, no known force or degeneracy pressure could stop it from continuing to collapse into a gravitational singularity.

      Thanks a lot... Before I was peacefully ignorant, but now you've tossed out a perfectly good question and revealed to me yet another topic for my List of Things I Know That I Don't Know...

      • Thanks a lot... Before I was peacefully ignorant...

        As long as you don't learn what you do not know about something "abnormal, non-Euclidean, and loathsomely redolent of spheres and dimensions apart from ours" http://en.wikipedia.org/wiki/Cthulhu [wikipedia.org], perhaps we may all remain peacefully ignorant. :)

    • by gstoddart (321705)

      What I want to know, is how did the universe expand beyond its own swartzchild radius?

      Man, for a moment I thought you were making a Spaceballs [imdb.com] joke, instead of a physics [wikipedia.org] reference. :-P

      Cheers

    • What I want to know. (Score:2, Interesting)

      by AgentPhunk (571249)

      Is how to answer my 5-year old's question of: "Ok, but whats outside the universe?"

      She gets solar systems, and has a pretty good handle on galaxies and that there are lots and lots of them. I'm still trying to explain the Big Bang, and keep getting hung up on what the universe is expanding INTO.

      I know, even us Big People don't have a good answer, but what the heck do you tell a kid?

      • Re: (Score:2, Informative)

        by Anonymous Coward

        http://curious.astro.cornell.edu/question.php?number=274 [cornell.edu]

        seems a good explanation to me ( the stretching sheet rubber part at least, or how things can grow apart without adding more rubber )

      • by Darth (29071)

        Don't worry. If she hasn't gotten the big bang by the time she graduates high school, she'll almost certainly get it in college.

      • Oh, I don't know... you could always let her believe in Santa Claus, the Easter Bunny, the Tooth Fairy, and God until she's old enough to decide on her own whether they're real?

      • by SBacks (1286786)

        There is nothing outside the universe.

        And, I don't mean emptiness. I mean nothingness.

        So, the universe is expanding, but its not expanding into anything, it just is.

    • Okay, err, not to be ignorant here, but where did the other black holes GO? How do they "die?"

      A quick look at the wikipedia article before my boss yelled at me to get back to work was not very enlightening.

      • Okay, err, not to be ignorant here, but where did the other black holes GO? How do they "die?"

        A quick look at the wikipedia article before my boss yelled at me to get back to work was not very enlightening.

        Black holes 'evaporate' through Hawking radiation.

        • That's what I got from wikipedia too, but the section on evaporation [wikipedia.org] seemed to indicate that a black hole would have to be less than a tenth of a milimeter in diameter in order to actually evaporate, because it's taking in more energy from background radiation than it's emitting.

          There didn't seem to be anything to explain how an actual sizeable black hole wouldn't just end up eating the universe.

    • by Kagura (843695)

      What I want to know, is how did the universe expand beyond its own swartzchild radius?

      How do you know it did expand beyond its schwartzchild radius?

      Sorry, that was a little zen. ;)

  • by NoNeeeed (157503) <slash@NOspAM.paulleader.co.uk> on Thursday October 16, 2008 @12:39PM (#25401629) Homepage
    Much like the collision between a server full of astronomy pictures and slashdot.

    Nothing survives.

    Oh, and as the mass increases, time slows down in the vicinity. Or at least that's how it seems.
  • The science (Score:5, Informative)

    by kinthalas (102827) on Thursday October 16, 2008 @12:41PM (#25401649)
  • ...must be millions of inhabited worlds, each populated by beings that believed themselves to be the center of the very universe, each believing that their existence had so much significance on the cosmic scale that this would not happen to them.

    Instead they find themselves in the most sucky situation in the entire galaxy...

    • Re: (Score:3, Insightful)

      by daem0n1x (748565)
      I guess these events happen in the million year range, so they may have had enough time to evolve and escape.
      • by hvm2hvm (1208954)
        Or kill themselves like some idiots we talk about some times.
      • by Kingrames (858416)
        More like the frog in a pot of hot water comparison I'd believe. It's very doubtful that the life inside those galaxies would escape, with the rare exceptions of the few who are mentally deranged and paranoid, or willing to risk their lives and the lives of others to explore beyond the limits of what they can see.

        And I can't wait to meet them.
  • Highlights from TFA (Score:5, Informative)

    by Emb3rz (1210286) on Thursday October 16, 2008 @12:43PM (#25401673) Homepage

    4C60.07 - the first of the galaxies to be discovered - came to astronomers' attention because of its bright radio emission. This radio signature is one telltale sign of a quasar - a black hole, spinning rapidly, feeding on its parent galaxy. A new image captures the moment, approximately 12 billion years ago, when this galaxy ripped a stream of dusty gas from a neighbour.

    "This new image reveals two galaxies where we only expected to find one," said Professor Rob Ivison ... "Remarkably, both galaxies contain super-massive black holes, each capable of powering a billion, billion, billion light bulbs. The implications are wide reaching: you can't help wondering how many other colossal black holes may be lurking unseen in the distant Universe?"

    Due to the finite speed of light, we see the two galaxies as they collided in the distant past, less than 2 billion years after the Big Bang. By now the galaxies will have merged to create a football-shaped elliptical galaxy. Their black holes are likely to have merged to form a single monstrously large black hole.

    "These two galaxies are fraternal twins. Both are about the size of the Milky Way, but each one is unique"

    From the thats-a-lot-of-lightbulbs department?

    • by kjllmn (1337665)
      What does "super-massive" in "super-massive black holes" mean? It's the opposite of a black hole light (light as in Coke light)?
      • It means a black hole of galaxy center dimensions, usually several million solar masses. There is a minimum mass for stable black holes, which was frequently quoted in the discussion on whether or not the LHC can produce an Earth-absorbing black hole. It's not near the energies available in the LHC, but you can have a "light" black hole of some solar mass as a result of the collapse of individual neutron stars if I recall
        What really got me in tfa was the "merged black holes" so. Do black holes actually
    • Re: (Score:3, Funny)

      by roman_mir (125474)

      Remarkably, both galaxies contain super-massive black holes, each capable of powering a billion, billion, billion light bulbs. The implications are wide reaching

      - yes, the implications are wide reaching. Where exactly are we going to get that many light bulbs from? We can't just let all that energy go to waste. Did anyone notice Usama bin Laden in close vicinity to the black hole? If so, can we please notify Bush?

    • From the thats-a-lot-of-lightbulbs department?

      Sounds more like the Eye of Harmony to me.

    • It's not only the number of light bulbs that's important here. One must also ask the wattage of each bulb in order to truly understand the amount of power represented. Are we talking 100 watt bulbs? Or 25 watts? Incandescent, LED, or CFL? The article is stunningly silent on this point...
  • Damnit. Who left the LHC turned on again!? How many times do I have to say it? When you leave the room please turn off the Large Hadron Collider.
  • Layman's question (Score:3, Interesting)

    by BCGlorfindel (256775) <`ac.unodnarb' `ta' `knessalk'> on Thursday October 16, 2008 @02:13PM (#25403019) Journal

    I know I aught be able to work this out myself, but I'm not sure if general newtonian calculations would be accurate. Is it possible to orbit a black hole from inside the event horizon if it is big enough? It seems intuitively obvious that if you can't achieve escape velocity you shouldn't be able to reach an orbital velocity either but I thought I'd see if someone was willing to give a more solid answer.

    • by clone53421 (1310749) on Thursday October 16, 2008 @02:21PM (#25403135) Journal

      No.

      Maintaining an outward velocity = c would keep you at the event horizon indefinitely. Add a sideways component and you'd be able to orbit, but at velocity > c. Anything lower and you'd need velocity > c just to maintain height, much less to orbit.

      If you could go fast enough you might be able to make a few passes in some sort of collapsing orbit, but a stable orbit would be impossible.

      • Re: (Score:3, Funny)

        by BCGlorfindel (256775)


        Maintaining an outward velocity = c would keep you at the event horizon indefinitely.

        The concept of standing still while having an enormous velocity makes my head hurt and my heart long for obedience to Newtonian physics.

        • Yeah, reading it after I posted it made my head hurt too, but I still can't figure out if there's a better way of saying it... or even if it's correct... >.<

          • by Xiroth (917768)

            No, it's sensible when you take into account the 'flipping' of time and space (radius) dimensions. Within an event horizon, the radius between the object and the centre of the mass becomes time-like - it can only ever increase, and doing so is pretty much inevitable. Time becomes vaguely space-like, although it's unclear if you can move in both directions along that axis, even in singularity conditions. In these conditions, the only way to move is to decrease radius (analogous to moving forward through time

    • Is it possible to orbit a black hole from inside the event horizon if it is big enough?

      Einstein's equations predict that once an object is inside the event horizon, curvature and tidal forces necessarily strictly increase, and appear to diverge (i.e., go to infinity) in finite proper time. Physicists call this a singularity. Presumably, quantum gravitational effects dominate when things get beyond a certain threshold, but it's not clear what exactly happens then.

      If a black hole is nonrotating, the smalles

  • by Parris (1340575) on Thursday October 16, 2008 @02:18PM (#25403091)
    "Remarkably, both galaxies contain super-massive black holes, each capable of powering a billion, BILLION, BIIIILLLLLLIIIIIOOOOONNNNN light bulbs." Why do I feel like Dr. Evil coauthored this article?
  • "this galaxy ripped a stream of dusty gas from a neighbour" Gee, and I got ticked when my neighbour nicked my cooking gas canister for his Bar b q.. Black holes and all that.. tsk, tsk ..
  • âoeRemarkably, both galaxies contain super-massive black holes, each capable of powering a billion, billion, billion light bulbs."

    Most people couldn't possibly conceive of such a number. Maybe they should tell us how many Libraries of Congress that number of bulbs could light.

    Can we get a better frame of reference than that please?

  • I think these findings start to beg the questions, is a colossal black hole at the center of every galaxy, and are galaxies created *because* of colossal black holes?
    • This remains one of the more interesting open questions. Did galaxies aggregate central black holes or did primeval black holes catalyse the formation of galaxies? A definitive answer would be at least worth a physics Nobel. It's also why I bothered reading this thread to the bottom.

  • When two neutron stars collide within our own galaxy, the resulting gamma burst can be a serious threat to life on Earth.

    How bad would it be if two galactic black holes collided? Would they emit gamma ray bursts as colliding neutron stars do? Would the energy be released in particular directions? If suitably (and very unfavourably) directed, is there any minimum safe distance within the observable universe from such a collision?

    • by RockDoctor (15477)

      When two neutron stars collide within our own galaxy, the resulting gamma burst can be a serious threat to life on Earth.

      Colliding neutron stars was, for a long time, one of the real contenders for an explanation for GRBs (Gamma Ray Bursts), but I believe that it has faded over the last half-decade or so, as increasing numbers of GRB afterglows have been imaged, and the fine detail of the bursts have become better constrained. The leading (by far) hypothesis these days is a "hypernova" which goes directly f

      • I'm more worried about not having cooked that haggis properly.

        Ah, good-o! I guess I shouldn't worry about looking into the pot and finding a neutron star made of haggis, either.

        [Sings a bit of Scotland's Depraved]

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