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Black Hole in Search of a Home

Posted by Zonk on from the don't-pick-up-that-hitchhiker dept.

jose parinas writes "Interesting news from the ESO observatory on Paranal about black holes that travel. From the article: 'For 19 of [the low redshift quasars], they found, as expected, that these super massive black holes are surrounded by a host galaxy. But when they studied the bright quasar HE0450-2958, located some 5 billion light-years away, they couldn't find evidence for an encircling galaxy. This, the astronomers suggest, may indicate a rare case of collision between a seemingly normal spiral galaxy and a much more exotic object harbouring a very massive black hole.'" More from the article: "Has the host galaxy been completely disrupted as a result of the collision? It is hard to imagine how that could happen. Has an isolated black hole captured gas while crossing the disc of a spiral galaxy? This would require very special conditions and would probably not have caused such a tremendous perturbation as is observed in the neighbouring galaxy. Another intriguing hypothesis is that the galaxy harbouring the black hole was almost exclusively made of dark matter." Update: 09/17 00:15 GMT by Z : Edited for clarity.

23 of 115 comments (clear)

  1. Hello? by DoubleEdd · · Score: 2, Insightful

    Could the moderators check the grammar before submitting?

    20 20 sounds like the results of an eyesight test, and ' found that for 19 of them, they found,' - what?

    1. Re:Hello? by IWannaBeAnAC · · Score: 2, Funny
      The very sad thing is, the mistakes were introduced because someone mistakenly thought they actually knew the English language, and edited the original article.

      An international team of astronomers [1] used two of the most powerful astronomical facilities available, the ESO Very Large Telescope (VLT) at Cerro Paranal and the Hubble Space Telescope (HST), to conduct a detailed study of 20 low redshift quasars. For 19 of them, they found, as expected, that these super massive black holes are surrounded by a host galaxy. But when they studied the bright quasar HE0450-2958, located some 5 billion light-years away, they couldn't find evidence for an encircling galaxy. This, the astronomers suggest, may indicate a rare case of collision between a seemingly normal spiral galaxy and a much more exotic object harbouring a very massive black hole.

  2. adoption by LiquidMind · · Score: 5, Funny

    I volunteer to adopt it, I think it would make a great companion plus the added perk of being an infinite power source.
    *rolls up newspaper* but if it starts behaving badly, we're gonna have a problem.

    --
    This sig contains repetition and redundancy.
    1. Re:adoption by EvilMonkeySlayer · · Score: 2, Funny

      Unfortunately it's super massive and eats anything that's near it.

      Sounds a lot like an ex-girlfriend.

    2. Re:adoption by Xilman · · Score: 2, Informative
      In fact, tidal forces at decent proximity to the event horizon will make protons and neutrons flow like water (the quarks and gluons in some cases as well...)

      Only for sufficiently small black holes. There is nothing locally special about a region near the event horizon. If the BH is big enough, 100M solar masses say, the tidal forces at its event horizon are small enough to let an astronaut pass through it without ill-effect. The same can not be said of the experiences encountered much closer to the singularity.

      Paul

      --
      Lasciate ogne speranza, voi ch'intrate
  3. Stephens theories,.... by crkpot · · Score: 2, Interesting

    I would be interested in how this data applies to the Stephen Hawkings theory of radiation expelled at the end of a Black hole - his come-back theory that everyone is still waiting to hear about. Dark Matter though compelling leaves us with more questions than answers.

    1. Re:Stephens theories,.... by Tango42 · · Score: 2, Informative

      You mean Hawking radiation? From what I remember, Hawking radiation is inversely proportional to the size of the black hole, so the radiation emited from a supermassive black hole like those in Quasars is almost non-existant.

  4. I'll never sleep again by Eradicator2k3 · · Score: 5, Funny

    "...a much more exotic object harbouring a very massive black hole."

    This brings Uhura's "exotic" dance in Star Trek V to mind.

    --
    Mr. T pitied this fool on 27 July 1992.
  5. Oh sure.... by Anonymous Coward · · Score: 5, Funny

    You let one in and there goes the whole neighborhood!

    1. Re:Oh sure.... by rubberbando · · Score: 3, Funny

      LOL...You are so spacist...

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      DEAD DEAD DEAD DELETE ME
  6. Article summary by jaymzter · · Score: 2, Insightful
    Astronomers investigating 20 20 low redshift quasars, found that for 19 of them, they found, as expected, that these super massive black holes are surrounded by a host galaxy.

    Definitely a case of grammatical structure in search of a home!
    --
    If thou see a fair woman pay court to her, for thus thou wilt obtain love
  7. I've seen something like this... by Anonymous Coward · · Score: 2, Funny

    Has an isolated black hole captured gas while crossing the disc of a spiral galaxy?

    If it's anything like my uncle, it doesn't capture gas, it releases it... in large quantities...

  8. Re:Gotta say ... by Trip+Ericson · · Score: 5, Funny

    Yeah, it was much simpler when everything was just God's will.

  9. Why couldn't it have by geekoid · · Score: 4, Interesting

    just 'consumed' the galaxy it started with? sure it would take a long time, but it's probably been there a long time.

    --
    The Kruger Dunning explains most post on /. http://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect
    1. Re:Why couldn't it have by forand · · Score: 2, Insightful

      The major problem with having a black hole eat an entire galaxy is conservation of angular momentum.

    2. Re:Why couldn't it have by Alsee · · Score: 2, Informative

      What do you mean by 'the stars in the galaxy have no "incentive"'? Is the gravity of the black hole not enough to get the stars moving towards it?

      Is the gravity of the sun not enough to get the earth moving towards it? Is the gravity of the earth not enough to get the moon moving towards it?

      Same thing. If there is non-zero angular momentum then gravity does not cause things to fall in, it causes them to orbit. Orbits can only decay and "fall in" if you find some way to bleed of the angular momentum. For example low earth orbit satellites slowly bleed off a little bit of angular momentum and eventually fall down due to the extremely thin atmospheric drag.

      -

      --
      - - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
  10. Chiral Dark Matter Galaxies by Anonymous Coward · · Score: 3, Funny
    The newest evidence hints that these types of dark matter galaxies are chiral in nature. Recent polarization readings of the detected light show that this quasar may be in a galaxy comprised of approximately 10^42 unmatched left socks. Another recently discovered quasar seems to be in a similar galaxy filled with unmatched right socks.

    Scientists are baffled as to how the different handed socks ended up in completely separate galaxies. However, some have stated that the apparent long-range transport phenomenon does provide hints for the mechanisms behind unexplained sock behaviors in this part of the universe.

  11. Dark matter? by bradbury · · Score: 5, Interesting
    An alternative explanation which is seldom discussed is that there could be a completely developed (mature) galaxy composed entirely of Kardashev Type II civilizations, also known as Matrioshka Brains. As was pointed out by Marvin Minsky at the Byurakan CETI conference in 1971 *advanced* civilizations, for thermodynamic efficiency reasons, will radiate their waste heat at slightly above the cosmic microwave background temperature. The VLT and HST which were used in these studies are incapable of detecting radiation at these wavelengths so any galaxies being managed by advanced civilizations would effectively be invisible.

    A reasonable person might well consider an explanation that included the natural evolution of advanced technological civilizations before they resorted to the invention of new particles and laws of physics (as is typically a requirement as soon as you mention 'dark matter').

    It is useful to keep in mind that several papers by Charley Lineweaver's group document that ~70% of the "Earth's" in our galaxy are significantly older than ours (perhaps billions of years older). It would not be that unexpected that from time to time we might encounter a galaxy where advanced civilizations had placed *all* of the reasonably available matter and energy "under management". (For the purposes of discussion we will assume that black holes do not constitute a "reasonably available" useful resource despite proposals from time to time that require rather creative physics to make them "useful".)

    1. Re:Dark matter? by bradbury · · Score: 3, Interesting
      No, I'm not Ray, though I am very distantly related. So you don't feel I'm appealing to "inaccessible literature", I post the following from the source proceedings (edited by Sagan).

      Dyson had made a set of points, one of which was:
      "Point 3. If a society is very highly developed technologically, it must emit intense infrared radiation, not necessarily a planetary spectrum, but necessarily a large intensity of infrared radiation, whether or not this society wishes to communicate. Consequently, we should use infrared radiation, as a signpost indicating priority areas toward which we should direct searches by radio and other techniques."

      There was some discussion which eventually led to the following exchange:

      OLIVER: Why do you suggest civilizations must of necessity produce large amounts of infrared radiation? It seems to me that the infrared radiation that would be produced by even a very much farther advanced civilization than ours would be negligible compared to their primary star. For example, in California, which has a very high usage of electricity, the power generation at the present time is only 0.1 percent of the sunlight falling on the state.

      DYSON: What I am saying is that the civilizations which are observable to us will have this character.

      OLIVER: But you are suggesting, are you not, that the infrared emission will be an observable characteristic? I am suggesting it is far down in the stellar noise.

      DYSON: No, I am saying that the generation of large amounts of infrared radiation is not necessarily an accompaniment of a high civilization at all. Only if it occurs is it something we can see.

      MINSKY: Since radiation at any temperature above 3K is wasteful and a squandering of natural resources, the higher the civilization, the lower the infrared radiation. We should look for extended sources of 4K radiation. There should be very few natural such sources.

      DYSON: I don't quite go along with this but to some extent you are right.

      The reason that Dyson didn't go along with this is because he still tended to view "advanced" civilizations as those operating on the basis of "biological" systems (remember this is 1971!) rather than engineered computational systems which can function at a much wider temperature range (in fact Likharev's "Rapid Single Flux Quantum Logic" (based on Josephson junctions) *have* to operate at temperatures much closer to those Minsky suggests). Thus AIs constructed of such devices would emit IR at a temperatures much lower than "primitive" civilizations (i.e. "wet" brain based) which function at the liquid water temperatures that Dyson tended to prefer.

      The theories behind Matrioshka Brains are in large part based on Minsky's observation, which are in turn related to Dyson's perspective reagarding Dyson "spheres" (really shells). They are however updated to recognize the fact that computational architectures which can support intelligence (and therefore advanced civilizations) can operate over a much wider temperature range (both higher and lower) than liquid water can provide.

      The complete proceedings from the conference can be purchased from Amazon for $3-7.

  12. Re:dark matter by Markus+Registrada · · Score: 2, Funny
    It's pretty clear the "dark matter" reference was just pro forma compliance with Astronomers' Union regulations. From the brochure:
    It's so embarrassing to be censured by the Union for leaving mention of dark matter out of one's press release, when it's so easy to drop in. It's not as if "dark matter" (or "dark energy", not yet required!) has any awkward properties to conflict with one's speculations. Even though one's own hypothesis may actually agree with observations and not need shoring up, just mentioning dark matter may help other astronomers who are not so fortunate. Please be considerate.
  13. In a police search a black hole was discovered in by diogenes57 · · Score: 2, Funny

    I read that headline as: a black hole was discovered in someone's home.
    I can imagine the scenario:
    Man: Don't go in there officer, trust me!
    Officer: Are you trying to hide something boy?
    Man: No, it's just that, umm...
    Officer: Well we'll just see about what's behind this door, shall we? ...Noooooooo...being sucked in...force of gravity too powerful...aaaaaaahhhhh!!!

  14. Looks like somebody was playing.... by infonography · · Score: 2, Funny

    Hungry Hungry Hippos, and just ran out of stars.

    --
    Sorry about the writing. Robot fingers, you know? Cliff Steele in DOOM PATROL #23
  15. It's that simple. by Hurricane78 · · Score: 3, Interesting

    The host galaxy is *inside* the black hole. It got "eaten" completely. To me this sounds pretty realistic if it's a huge black hole...

    --
    Any sufficiently advanced intelligence is indistinguishable from stupidity.