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Space Science

Black Hole Cluster Spawns Massive Cloud 74

Posted by kdawson from the excuse-me dept.
Shifty Jim writes in with an article at space.com reporting that a cluster of galaxies harboring black holes may be the source of a massive cloud millions of light years across. Quoting: "A giant cloud of superheated gas 6 million light years wide might be formed by the collective sigh of several supermassive black holes, scientists say. The plasma cloud... might be the source of mysterious cosmic rays that permeate our universe... The plasma cloud is located about 300 million light years away near the Coma Cluster and is spread across a vast region of space thought to contain several galaxies with supermassive black holes... embedded at their centers."
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Black Hole Cluster Spawns Massive Cloud More

Black Hole Cluster Spawns Massive Cloud

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  • Nothing to see here?!!! (Score:3, Funny)

    by Anonymous Coward on Sunday April 22, 2007 @03:55PM (#18834257)
    I know, it's a black hole!

    • Re: (Score:3, Interesting)

      by beset ( 745752 )
      It still boggles the mind that anything we see now will have happened 300,000,000 years ago.

      The system / actions we're only just seeing happen now might have already been destroyed by old age / a huge intergalactic war. My money is on Lrr from Omicron Persei VIII.
      • Another cluster of galaxies destroyed due to a shortage of human horn... (they should just come here to /.!)

        Still, it is mind blowing... but now, add to this the theories about time and how we perceive it, and you have the perfect conversation for Thanksgiving dinner when you want to baffle, confuse, and scare everyone else at the table.

  • Not news (Score:5, Funny)

    by larry bagina ( 561269 ) on Sunday April 22, 2007 @04:00PM (#18834283) Journal
    Cowboy Neal's black hole spawns a massive cloud of stink on a daily basis.

  • I just read about this on AICN! (Score:3, Funny)

    by Anonymous Coward on Sunday April 22, 2007 @04:02PM (#18834297)
    It's Galactus!

  • At least it's not SPAM (Score:3, Interesting)

    by anss123 ( 985305 ) on Sunday April 22, 2007 @04:04PM (#18834313)
    But I'm totally clueless how a Black hole can spawn anything. I thought they were 'Black holes', or have that changed recently?

    • Re:At least it's not SPAM (Score:5, Informative)

      by kennelly ( 704333 ) on Sunday April 22, 2007 @04:11PM (#18834371)
      Google "Hawking Radiation". (Thermal radiation thought to be emitted by black holes due to quantum effects - named after British physicist Stephen Hawking, who provided the theoretical argument for its existence in 1974.)

      • Re: (Score:2)

        by khallow ( 566160 )
        It's not Hawking radiation. That declines as the black hole becomes more massive.

      • Re:At least it's not SPAM (Score:5, Insightful)

        by owlstead ( 636356 ) on Sunday April 22, 2007 @04:43PM (#18834583)
        Yesss, but I've just read some books on that, and I wonder if there would be enough Hawking Radiation to create an enormous superheated gas cloud. I mean, from wikipedia on Hawking radiation:

        "The power in the Hawking radiation from a solar mass black hole turns out to be a minuscule 1028 watts. It is indeed an extremely good approximation to call such an object 'black'."

        I mean, how heavy do you want those things to be? Its more likely that the radiation comes from the enormous forces excerted on matter around these black holes, not from the black holes themselves.

        • Re: (Score:3, Interesting)

          by owlstead ( 636356 )
          Ugh, stupid copy/paste, that's 10 to the power of -28 watts. Not that much. Not enough to power a postcard with one of these irritating battery/chip/speaker combinations in it. Allthough these things may also be powered directly the dark forces that surround them.

          • Not enough to power a postcard with one of these irritating battery/chip/speaker combinations in it. Although these things may also be powered directly the dark forces that surround them.
            Um, just who are you sending these cards to, exactly? Does Hallmark have a new Santeria line?
        • I think the answer is a lot simpler than that anyway. Don't forget, black holes create a huge gravitational potential gradient. If you have a big enough one, it will heat up an awful lot of stuff that's trying to spiral in and cause it to give off all sorts of interesting radiation. And if it's been around for billions of years in a (relatively) dense piece of space, I don't think it's unreasonable that that energy could have bled off and affected a huge area.

          • Re: (Score:2)

            by fbjon ( 692006 )
            What I'm wondering is, is it even possible to see the blackness of a black hole? Won't it be obscured by all the radiation from the stuff going into it, making it into a kind of star?
            • Not all black holes are surrounded by a large cloud of material falling in, some black holes can be "naked" and give off very little radiation. Of course if it isn't giving off radiation then obviously they are hard to detect because there is nothing to see. Gravitational lensing is one possible way to detect a black hole in that case.
          • Sooo... It's not just radiation that causes matter formation around blackholes. Black hole is so freaking massive that explosions near or close to it, it's rotation it's self, and crushing gravity bobbing up and down in the space time around it, will cause shockwaves to ripple through spacetime clumping any matter and radiation that has been thrown off the blackhole together into either clouds of matter, or stepping even further to cause the matter to collapse into smaller objects such as stars, dark matte

        • Re: (Score:2)

          by Mal-2 ( 675116 )

          "The power in the Hawking radiation from a solar mass black hole turns out to be a minuscule 10^-28 watts. It is indeed an extremely good approximation to call such an object 'black'."


          Not to mention that "really, really, really dark gray holes" just doesn't flow.

          Mal-2

    • Re: (Score:3, Informative)

      by flyingfsck ( 986395 )
      Black holes actually do radiate - they are actually not black at all. The result is that small black holes will evaporate and disappear after a while. Bigger ones are probably indistinguishable from an ordinary star when viewed from a distance. The difference being their mass which would be disproportionate to their luminosity. Read Hawking's "A Brief History of Time" for illumination.

      • Re:At least it's not SPAM (Score:5, Informative)

        by Kandenshi ( 832555 ) on Sunday April 22, 2007 @04:36PM (#18834547)
        Actually, it's the *really* small ones(on the order of the mass of maybe half the moon, or smaller) that evaporate very quickly. The supermassive ones radiate at a very low rate and will last many, many, many billions of years. The temperature of the universe(eg: background radiation) will need to drop before they'll be "hotter" than their surroundings. Currently the big black holes are soaking up more radiation than they're emitting(hence, black)

      • Re: (Score:3, Informative)

        by Fujisawa Sensei ( 207127 )

        I suggest you learn a little bit of the math behind black hole evaporation.

        Here I refer to Wikipedia because I'm lazy...http://en.wikipedia.org/wiki/Hawking_evapor ation#Black_hole_evaporation [wikipedia.org]

        You'll notice that from the Power emitted from a black hole is inversely proportional to the Mass Squared, so Big Black holes don't emit much power, making them effectively black. Not you described indistinguishable from a star when viewed from a distance.

        Also the time it takes for a black hole to evaporate is prop

        • Also its my understanding that these equations assume that the black hole is not feeding and gaining mass.

          Yeah, a "dormant" black hole can be practically invisible and very hard to detect on their own, and then they use to need to make more assumptions from the surrounding environment. Often they use a combination. Sagittarius A* is currently assumed to be ("the"?) supermassive black hole in the center of the Milky Way and is observed through radio emissions and nearby rotating stars alike. Hawking radiati
      • Seriously, the parent completely misstated the intensity of hawking radiation. I can't believe it got modded up to 4 in the first place.

        Now, black holes are often surrounded by bright clouds, but the clouds are bright for reasons completely unrelated to hawking radiation. As stuff falls into a black hole, it gets accelerated until it's going really fast. Once it gets fast enough, the light generated by the friction of the things falling in gets blue-shifted until it moves into the x-ray range. Now, this doe
        • I agree, and it seems the mods have still not woken up here. :-(

          The light we indirectly detect black holes from is thanks to superaccelerated matter near their Schwarzschild radius.
      • Read Hawking's "A Brief History of Time" for illumination.

        That pun brightened my day!
      • Black holes actually do radiate - they are actually not black at all.

        More like... charcoal. Yeah. Charcoal.

    • Re:At least it's not SPAM (Score:4, Funny)

      by j00r0m4nc3r ( 959816 ) on Sunday April 22, 2007 @04:36PM (#18834551)
      Get with the times. White is the new black.
    • A blackhole all alone only has hawking radiation to get out.
      However, since the article talks about clusters, surely there would be some fragments sent out if there was a collision between blackholes.

      In another thing, no matter how large the blackhole is, it is still dwarfed by the galaxy it resides in - isn't it just as likely that the galaxies exist simply because there is a large amount of building material around - just like lots of planets are built around a sun with lots of dust.
      • AFAIK the magnetic field of a black hole can also cause it to send out jets of schtuff, so it is no only Hawking radiation that can cause it to lose mass.
        • The jets produced by a black hole originate outside of it, not inside of it. The black hole does not lose mass by producing jets.

    • Re: (Score:1)

      by osu-neko ( 2604 )
      Parse the sentence more carefully. It never said the black holes spawn anything, it says the cluster does (and the summary more carefully says the "cluster of galaxies").
    • It is a ORI ship coming out of a supergate

    • Matter on the way into a black hole gets compressed by the immense gravity to tremendous pressures, forming an accretion disk [wikipedia.org], which radiates mostly x-rays and similar forms of high-energy radiation. It isn't really the black holes that are radiating, but the matter falling in that does. Tossing matter into a black hole is probably a far more efficient way of converting matter into energy than even nuclear fusion.

      Hawking radiation probably isn't what's going on here. The temperature of a typical stella

    • In this case, the radiation and energy involved comes from the accretion disk. As black holes pull in matter, the energy gained as it falls down the gravitational potential and the friction between matter produces huge amounts of heat, most of which is radiated away as gamma-rays or x-rays.
    • FTFA: "The cloud might be evidence that AGNs convert and transfer their enormous gravitational prowess, by a yet-unknown process, into magnetic fields and cosmic rays that spread across the universe."

      That's how :-) but clearly Hawking radiation is not a relevant process as it is far too weak from supermassive black holes.

      Black holes that are accumulating mass from accretion disks are the source of huge amounts of radiation as the matter spirals around and into the hole and heats up enormously in the process
    • Pretty much anytime someone talks about a black hole observation they are actually talking about an accretion disk around a black hole. Just about the only exception I can think of gravitational lensing. Although the article does not go into much detail, it is likely that the theory implicates some coincidental activity of matter falling into the black holes from their accretion disks, the resulting release of energy being the cause of heating of this cloud of gas.

      By the way, since scale can be hard to a

  • Spinning Disc Doctor (Score:5, Funny)

    by BillGatesLoveChild ( 1046184 ) on Sunday April 22, 2007 @04:11PM (#18834375) Journal
    > But I'm totally clueless how a Black hole can spawn anything.

    Black holes spawn a lot of interest, debate, Stephen Hawking's Theses, one Disney movie and an endless source of Deus ex machina. http://en.wikipedia.org/wiki/Deus_ex_machina [wikipedia.org] .

  • might be? (Score:3, Interesting)

    by passionfruit ( 1091373 ) on Sunday April 22, 2007 @04:27PM (#18834477) Homepage
    might be the source?

    might be?

    there are probably a zillion black wholes and a gazillion such "cosmic clouds of superheated gas" in the universe. so what makes this guy think this particular "cloud" has agreater probability of being the source of the "cosmic rays" that "permeate" our universe?

    • Re:might be? (Score:5, Informative)

      by owlstead ( 636356 ) on Sunday April 22, 2007 @04:49PM (#18834635)
      "so what makes this guy think this particular "cloud" has agreater probability of being the source of the "cosmic rays" that "permeate" our universe?"

      They don't:

      "he new finding could also help explain the unwanted and confusing "noise" scientists observe in the Cosmic Microwave Background (CMB), Kronberg said. The CMB is a ubiquitous radiation in the universe that is said to be a remnant of the Big Bang."

      Now, if you read that carefully, it is said that this could explain the *noise* in the CMB, not the CMB itself. Half a point for reading through the article though.
      • You've got the Cosmic Microwave Background (CMB) and cosmic rays confused. Cosmic rays are very fast moving electrons/protons etc - what causes them isn't entirely understood. Microwaves are photons, which are more-or-less radio, the origin of the CMB is understood.

        TFA pretty clearly states that the scientist in question does think that the cloud might be related to the cosmic ray production as well as CMB noise:

        The plasma cloud, detailed in April 10 issue of Astrophysical Journal, might be the source of my

    • Funny thing that. Much like our knowledge of ancient human history, the further out we look the less reliable our knowledge is. So yes scientists will use words like possibly, likely, perhaps, maybe, and so on because we really can't know until our technology improves to the point where we can make more reliable direct observations and measurments. People forget that the majority of our knowledge of the physical universe is theory.

  • currently? (Score:5, Insightful)

    by icepick72 ( 834363 ) on Sunday April 22, 2007 @05:35PM (#18834977)
    The plasma cloud is located about 300 million light years away near the Coma Cluster


    Correction: was located


    That's that damnest thing about observing something 300 million light years away.

  • Wow (Score:1, Flamebait)

    by johansalk ( 818687 )
    A cluster of black holes is a literal clusterfuck.
    • by sending out Beowulf Schaeffer in a singleship. We might be facing a Pak protector invasion soon, in front of the cosmic ray blast that will sterilize our planet. /grin

      My physics is from the mid 80's so it is 20+ years out of date. But what I remember is that if you put a black hole inside a hydrogen cloud, all the hydrogen and anything else that gets sucked inside the Schwartzchild radius will be ripped apart and converted to energy and approximately half of that energy will be radiated outwards, t
  • Bad article to read after reading the goatse.cx for sale [slashdot.org] article...

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