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Hundreds of Black Holes Roam Loose In Milky Way 254

sciencehabit writes "From Science: 'Astronomers suspect that hundreds of medium-sized black holes are roaming loose in the Milky Way. These rogues, according to a new study, are the orphaned central black holes of the many smaller galaxies that the Milky Way has swallowed over its billions of years of existence.'"
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Hundreds of Black Holes Roam Loose In Milky Way

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  • by adnonsense ( 826530 ) on Thursday April 30, 2009 @06:04AM (#27770203) Homepage Journal

    Anything else we need to be worrying about?

    • Global warming, fundamentalist christian, jews, muslims, poisonous food additives,and a global echonomic collaps can be a good start. :D

      • Re: (Score:3, Interesting)

        by Opportunist ( 166417 )

        At least you left out all the conspiracy crap, like alien invasions, mind control probes and terrorism.

        • Re: (Score:2, Funny)

          by jeffshoaf ( 611794 ) *

          At least you left out all the conspiracy crap, like alien invasions, mind control probes and terrorism.

          That's because the alien conspiracy has already used their mind control probes to make him forget about terrorism.

      • Global warming, fundamentalist christian, jews, muslims, poisonous food additives,and a global echonomic collaps can be a good start. :D

        That list says quite a bit about your views. ;-)

      • Re: (Score:3, Funny)

        by kid_oliva ( 899189 )
        Parent should be rated "Funny", not Informative. Didn't you notice the ":D" at the end. It is called sarcasm. Now please rate me Informative as I have explained the previous post. Thank you. :D
      • by bugeaterr ( 836984 ) on Thursday April 30, 2009 @09:10AM (#27771561)

        Global warming, fundamentalist christian, jews, muslims, poisonous food additives,and a global echonomic collaps can be a good start. :D

        Nothing a rogue black hole can't fix, or at least make a LOT smaller.

      • Re: (Score:2, Offtopic)

        by Gilmoure ( 18428 )

        Squirrels? Just saw a documentary about a girl who got squirrels in her pants [youtube.com].

    • by Nephrite ( 82592 ) on Thursday April 30, 2009 @07:09AM (#27770573) Journal

      Looks like everyone has already forgot the LHC...

    • by mrsquid0 ( 1335303 ) on Thursday April 30, 2009 @07:29AM (#27770703) Homepage

      And the biggest risk that most of us face, getting hit by a car on the way to work.

      • by Opportunist ( 166417 ) on Thursday April 30, 2009 @07:52AM (#27770829)

        That's what has puzzled me to no end since the onset of various hypes. SARS? Your chance to catch it? Play the lottery if you do, your chance for a jackpot is higher. Mad cow? Ditto. Terrorism? 3000 affected of roughly 200 million (directly, not due to the political fallout). Swine/bird flu?

        And now compare that to the chance of a heart attack. Lung cancer. Getting run over by a car. Getting mugged. And various freak accidents that happen all the time.

        It's a miracle that you're still alive! And it's not because of black holes, not because of terrorism, not because of pandemics. It's because you're living.

        Your alternative is to spend your life under your bed. But then again, where's the difference to being dead already?

        • Re: (Score:3, Insightful)

          by Anonymous Coward

          It's not that. The government and it's agencies MUST overreact to these things, or at least hype the media up to let them know they are doing "everything they can" in light of the unfortunate turn of events Katrina caused. Because we didn't overreact at that time, a sh**load of angry black people came out of the woodwork looking for a FEMA handout because Kanye announced Bush hates black people. Now don't flame the comment as racist, it's not, but it was a very dynamic situation that people capitalized o

        • by mrsquid0 ( 1335303 ) on Thursday April 30, 2009 @08:52AM (#27771367) Homepage

          > Your alternative is to spend your life under your bed. But then
          > again, where's the difference to being dead already?

          I am not going to spend my life under my bed. That's where the monsters live.

          • And you would miss all that fun? It would certainly make your life worth, I mean, who doesn't like monsters? And no need to worry about getting hit by a car, catching swine flu or getting raped by some desperate pretty blonde girl on the street...

            Come on man, you've that ultimate chance, would you go for it or just let it slip?

        • by PhxBlue ( 562201 ) on Thursday April 30, 2009 @08:54AM (#27771381) Homepage Journal

          Your alternative is to spend your life under your bed. But then again, where's the difference to being dead already?

          About six feet. *Rimshot!*

        • Re: (Score:2, Insightful)

          by Anonymous Coward

          I agree with you about terrorism, etc but...

          > SARS? Your chance to catch it? Play the lottery if you do, your chance for a jackpot is higher. Mad cow? Ditto

          You're using some hindsight there and really missing the history of the events.

          * SARS -- brand new virus, very high fatality rate initially (higher than spanish flu, for example) and seemed likely to be very spreadable: went from unknown to thousands of cases VERY quickly. In many respects looked like a probably pandemic.

          What spared us: most people t

        • I wonder if one of these bloggers (and their apparently-infinite spare time) could add up ALL the various possible dangers, and the odds of it happening in a given year...odds of getting hit by lighting, 1:22 million. Odds of being in a car accident 1:50,000, etc, etc...I suspect that once you compiled a comprehensive list, you'd end up being nearly certain you'll die in the next year.

          • Re: (Score:3, Interesting)

            by jc42 ( 318812 )

            ... add up ALL the various possible dangers, and the odds of it happening in a given year...odds of getting hit by lighting, 1:22 million. Odds of being in a car accident 1:50,000, etc, etc...I suspect that once you compiled a comprehensive list, you'd end up being nearly certain you'll die in the next year.

            A few years back, I read an interesting article whose authors pretty much did just that, and wrote about the conclusions. One of their more interesting ways of expressing the results of the study was:

    • Space Invaders. Giant monkeys throwing barrels.

    • The Spanish Inquisition?

      (Bet you didn't expect that!)

    • Well, I would like to know, if a black hole comes by, does it actually pull a whole planet into its hole, do we know if this is possible...I mean at the core a small start implodes and turns into a black hole, but does it have enough strength to suck in another star, or even a whole solar system...and what happens if you put 2 black holes side by side, do they cancel each other out...sort of like putting a bag of holding inside a bag of holding...?

      • Well, I would like to know, if a black hole comes by, does it actually pull a whole planet into its hole, do we know if this is possible...

        If it has sufficient gravity, then yes, it is quite capable of "swallowing" a planet. Any black hole that formed in the "usual way" from a collapsing star, certainly has enough gravity (pretty much exactly the same as the star that it was before it collapsed) to suck in a nearby planet if the planet is unfortunate enough to be nearby. Of course, that's only really a problem with these "wandering" black holes - if our sun was mystically replaced with an equally massive black hole (which would be MUCH smaller in size), then the planets would continue to go around it exactly as they do now (although we'd all die from freezing since the hole isn't putting out heat like our sun does, but that's another matter entirely)

        I mean at the core a small start implodes and turns into a black hole, but does it have enough strength to suck in another star, or even a whole solar system...

        Again, depends on the size (gravity) of the hole, but generally yes - put two stars on a collision course and it'll be pretty nasty.

        and what happens if you put 2 black holes side by side, do they cancel each other out...sort of like putting a bag of holding inside a bag of holding...?

        Nope, they'd just "merge" in to one bigger one. So, two that had a mass of x, would become a single one with a mass of 2x.

        Black holes are pretty weird and there's a lot of strange physics around them when you get deep in to it, but at the very basic level, they're not particularly odd at all - just think of them as objects with a REALLY large mass for their size (but still no larger than many other objects around, such as stars (of course, holes that used to be galactic centres are generally a bit bigger, since our best theories regarding black hole galactic centres involve a LOT of matter going in to creating them)).

      • by jc42 ( 318812 ) on Thursday April 30, 2009 @03:45PM (#27777617) Homepage Journal

        A couple of years ago, there was an astronomy news story about the discovery that our nearest spiral-galaxy neighbor, the Andromeda Galaxy, has two large black holes (with masses of several million sols) in its core. This explained some of the anomalies in that galaxy's shape, which isn't quite as flat or symmetrical as you'd expect a big spiral to be. The suggested explanation is a merger with another galaxy that probably happened several billion years ago, long enough that the resulting mess has settled down into what at first glance looks like a single normal spiral galaxy.

        This isn't at all unusual, though. There are lots of galactic collisions visible in space. There was a fun one a few days ago on the Astronomy Picture of the Day [nasa.gov] site. Stories on them generally explain that few if any of the stars collide, because they're too far apart. The dust and gas clouds do collide, and the result is a period of star formation. In many cases, simulations show that the galaxies merge, typically producing an elliptical galaxy if both were large and had different orientations. In the Andromeda case, they were probably roughly coplanar, so the merger just produced a slightly bigger spiral.

        Another recent story is about calculations showing that the Andromeda and Milky Way galaxies are on a collision course, and will collide in several billion years. The result may look a lot like the above picture to astronomers in other nearby galaxies.

        Astronomers have also found the remnants of several smaller galaxies that our Milky Way has gobbled up. They were generally disrupted, but most of the stars from a single such galaxy now have similar orbits, so each appears as a loose "stream" of stars with a thickening that corresponds to the core of the original small galaxy. It's likely that each such smaller galaxy contributed one or more "medium" black holes (with a few thousand solar masses) to our galaxy.

        Anyway, this story isn't especially surprising to anyone who follows atronomy news.

    • Anything else we need to be worrying about?

      Apparently, yes. The political appointee in the White House who plans $300,000 photo ops involving Air Force One, F-16s, and major landmarks... he seems to be worth keeping an eye on.
  • by Dutchmaan ( 442553 ) on Thursday April 30, 2009 @06:07AM (#27770225) Homepage
    Perhaps all our money really WAS disappearing through a black hole!
  • by MichaelSmith ( 789609 ) on Thursday April 30, 2009 @06:08AM (#27770233) Homepage Journal
    I wonder if black holes could account for either of these things? Gamma rays would be released if a large mass hits a black hole. A cosmic ray could be accelerated if it passes too close to a black hole.
  • by Anonymous Coward on Thursday April 30, 2009 @06:08AM (#27770237)
    My kind of galaxy!
  • Nah, I call BS (Score:4, Interesting)

    by DavidRawling ( 864446 ) on Thursday April 30, 2009 @06:13AM (#27770269)
    Scenario. The Milky Way swallows a galaxy, and by extension, all the stars around the central black hole. Yet, the same gravity that causes the stars to amalgamate completely misses the biggest mass in that swallowed galaxy? Why would that make sense?
    • Re:Nah, I call BS (Score:5, Interesting)

      by MichaelSmith ( 789609 ) on Thursday April 30, 2009 @06:22AM (#27770327) Homepage Journal

      Scenario. The Milky Way swallows a galaxy, and by extension, all the stars around the central black hole. Yet, the same gravity that causes the stars to amalgamate completely misses the biggest mass in that swallowed galaxy? Why would that make sense?

      The only bit which I think is strange is that the black hole from the swallowed galaxy hangs around in our galaxy. It should have enough velocity to pass right through our galaxy and never come back. Most likely the captured stars would die of old age before they passed though our galaxy. Only red dwarfs would keep going because of their long life. Gas clouds in the captured galaxy would interact with our gas clouds. I think that is the only component which would really get captured.

      • by 4D6963 ( 933028 )
        What makes you think the black hole would have a trajectory any different from any of the stars from the captured galaxy? Because it's marginally heavier than the other stars?
        • What makes you think the black hole would have a trajectory any different from any of the stars from the captured galaxy? Because it's marginally heavier than the other stars?

          I think the black hole and stars from the captured galaxy will not change their trajectory when they enter our galaxy. Gas clouds will change their trajectory because they are big and diffuse. The galaxy will appear to be captured because the bright stars inside it will burn out and no more will be born with the original trajectory because the gas clouds have gone.

          • by 4D6963 ( 933028 )
            Right, of course you realise that it's all infirmed by both galaxy collision simulations and actual galaxy collisions that we can look at, right? You're clearly underestimating the gravitational pull that our galaxy has. Or am I misunderstanding what you were trying to say? (that wasn't very clear to me)
      • Re: (Score:2, Informative)

        by markusre ( 1521371 )
        since the gravitation force is ~M_blackhole*M_milkyway and F_bh=m_bh*a i dont think the trajectorie is dependent on the mass of the particle in the first order as long as m_bhm_milkyway
        • since the gravitation force is ~M_blackhole*M_milkyway and F_bh=m_bh*a i dont think the trajectorie is dependent on the mass of the particle in the first order as long as m_bhm_milkyway

          No but the velocity change caused by drag depends on the density of the object. Stars and black holes won't experience significant drag. Gas cloud molecules will. When they hit another cloud gas will be compressed in a shock wave and new stars will form.

    • Re:Nah, I call BS (Score:4, Interesting)

      by Brown ( 36659 ) on Thursday April 30, 2009 @06:24AM (#27770333) Homepage
      The Milky Way swallows a galaxy, and the swallowed galaxy's stars get added to the milky way, orbiting the galactic centre in the usual way. Presumably the same happens to the black hole - there's no reason why it should be sucked into the middle. Black holes will happily orbit around each other, as long as they're outside each other's event horizons.
      • The Milky Way swallows a galaxy, and the swallowed galaxy's stars get added to the milky way, orbiting the galactic centre in the usual way. Presumably the same happens to the black hole - there's no reason why it should be sucked into the middle. Black holes will happily orbit around each other, as long as they're outside each other's event horizons.

        Why would the stars and black hole change their trajectory significantly? They are passing through a near perfect vacuum. I could believe that a galaxy from the halo of our galaxy could pass through our galactic disc and lose all its gas clouds, but the black hole would keep right on going.

        • Re:Nah, I call BS (Score:5, Interesting)

          by AlecC ( 512609 ) <aleccawley@gmail.com> on Thursday April 30, 2009 @07:03AM (#27770539)

          Because the galaxy is not a point mass. Most ordinary star/planet modelling is based on viewing each object as a sphere, which behaves as a point mass at the centre. But when you penetrate inside another body, as two galaxies do when they collide, this simplification no longer applies. Some of the mass of the "other" galaxy moves behind the penetrating galaxy, slowing it down rather than, as the point mass model would suggest, continuing to accelerate into the centre. In the simplest model, of inter-penetrating spheres, gravity no longer has an inverse square law but an inverse linear law. Of course, galaxies are not uniform spheres, and the modelling is much harder. However, it is widely accepted that when two galaxies collide, they merge and the vast majority of the mass forms a single galaxy - though clusters may be flung out. If the galaxies are of broadly similar masses, the distinctive spiral structure is wiped out and the merged result becomes an elliptical galaxy for a few hundred million years before the spiral structure re-establishes.

          Google "andromeda collisions" for simulations of the collision between our galaxy and the Andromeda galaxy in about 3 billion years.

          • Yes I can see that your argument might work as a gravitational slingshot. The way I visualise it is that the time you spend on certain trajectories in a gravitational field can determine the amount of energy you transfer through the field. A helicopter hovering above the ground will use an infinite amount of energy in an infinite time. A satellite can orbit the Earth for an infinite time for zero energy cost. If I fall towards jupiter and fire an engine at accelerate at closest approach I will spend less ti
          • It's also worth pointing out galaxies orbit each other and when the galaxies are of similar size you get repeated collisions [nasa.gov] before a merger. Black holes were a mathematical conjecture when I was a kid and we still tend to think of galaxies as islands that occasionally bump into each other but advances in astronomy and computing are telling us it's a much more dynamic [harvard.edu] and structured [youtube.com] universe than we thought existed 30-40yrs ago.
          • Re: (Score:3, Funny)

            by Shakrai ( 717556 )

            But when you penetrate inside another body

            There aren't too many slashdotters that can relate to your analogy. May I suggest a car one instead? ;)

        • by Brown ( 36659 )
          There is clearly enough gravitational pull from the galactic centre to keep the milky way together, despite its spin - so presumably this would have a considerable effect on other smaller galaxies passing through it, especially if their relative velocities were low in relation to their size.
      • Re:Nah, I call BS (Score:4, Interesting)

        by stonewallred ( 1465497 ) on Thursday April 30, 2009 @07:29AM (#27770699)
        What happens when two black holes actually intersect at their event horizons? Inquiring non-astrophysicists would like to know.
        • Re:Nah, I call BS (Score:5, Informative)

          by beanyk ( 230597 ) on Thursday April 30, 2009 @08:12AM (#27770983)

          What happens when two black holes actually intersect at their event horizons? Inquiring non-astrophysicists would like to know.

          They merge into one bigger hole. The final hole mass will be (almost) the sum of the two masses, and will likely have a significant spin, even if the pre-merger holes don't.

          Disclaimer: this is actually my area of research.

        • by evanbd ( 210358 )

          They merge into a single black hole, spherical except for the deformations resulting from spin. If they're in close orbit, they'll lose energy to gravity waves and other forms of radiation (both Hawking and synchrotron) and spiral into each other. The gravity waves should be quite strong -- one of the sources that LIGO etc ought to be able to detect.

          Of course, IANAA either, so I might be off base here, but that's my recollection as to what happens.

        • A massive energy release. Much of the energy is released as EM, but a great deal of it comes in the form of gravity waves. Observatories like LIGO are hoping for black hole collisions, because they're some of the strongest gravity wave sources we'd expect to see.
        • Just guessing, but from the outside they probably look like two blobs joining into a single blob.

          A more interesting question would be, what if the universe is shaped kind of like a 3-d donut (with 3-d "surface", folded in 4-d), and you take so many black holes that you can string them together and make a "belt" out of them. Will it remain as a stable "black belt"?

          Dibs on nomenclature!

    • by anandsr ( 148302 )

      I wouldn't have much faith in this, precisely because it would have been done based on Newtonian gravity. It does not take care of the MOND phenomenology. With MOND in the picture things may be totally different.

      MOND is an empirical equation which predicts the rotation curves based on the visible mass in Galaxies. It works beautifully at Galactic scales but does not work well at cluster scales.

      We know that General Relativity (GR) and Quantum Mechanics (QM) both are mutually incompatible, which indicates tha

  • Milky Way? (Score:5, Funny)

    by krou ( 1027572 ) on Thursday April 30, 2009 @06:21AM (#27770313)

    If I found hundreds of "black holes" in my "Milky Way", surely that would mean it's an Aero?

    I'll grab my coat ...

    • by L4t3r4lu5 ( 1216702 ) on Thursday April 30, 2009 @06:59AM (#27770525)
      Well, if the universe is expanding in a uniform fashion, the perimeter in all directions must be equidistant from the centre.

      I think you mean a Malteser.
      • I always thought the universe was a hyperbolic paraboloid... hence it's actually a Pringle

        • I tried looking up why you said that, and came up with this. [wikipedia.org] All well and good.

          I then had to read this [wikipedia.org] and this [wikipedia.org] and this [wikipedia.org] and and this [wikipedia.org] and this [wikipedia.org] and this [wikipedia.org] and this [wikipedia.org] and this [wikipedia.org] and this [wikipedia.org] and this [wikipedia.org] and this [wikipedia.org] and this [wikipedia.org] to explain why people think it's a different type of curve.

          I now couldn't give a hoot if it's a sphere, a parabaloid, or atop a giant turtle right now.In fact, the turtle makes more sense.

          I wonder if A'Tuin eats grass or astroturf. (Shameless FotC link).
    • Anybody want to bid?

      For gods sake don't let them go. You could feed Osama Bin Laden into them a bit at a time and power a small city.

  • and it sounded like a cartoon.
    • This shouldn't even be news,

      "Coming up next: The earth is in orbit around the sun, Liquid Nitrogen is cold; and why sleeping inside an active rock tumbler may be damaging to your health."

    • by Destoo ( 530123 )

      The only image I had was that they were looking for Hawking, floating around to find his wheelchair, in a cosmic-sized pacman game.

  • by VShael ( 62735 ) on Thursday April 30, 2009 @06:45AM (#27770441) Journal

    And how can the news networks use it to induce fear?
    And more importantly, how we can we use it to sell stuff?

    "Black hole protective face-masks" just don't seem like a seller, to me.

    • by PolygamousRanchKid ( 1290638 ) on Thursday April 30, 2009 @07:09AM (#27770575)

      The Black Holes were created by the Large Hadron Collider during the short time that it was online, before the radioactive liquid helium leaked out and freeze-burned its way down toward the center of the earth (China Syndrome), where it was reflected back up and surfaced in a pig patch in Mexico, and irradiated sick pigs with Swine Flu, which mutated into the Mexico Flu, and hopped a ride on some poor little kid, who passed it on to Mexico city.

      Seems all pretty plausible to me.

    • by Dan541 ( 1032000 )

      Does your home insurance cover "Black hole damage"

  • The media is currently in doomsday-mode, so please Slashdot, be careful with these juicy stories suggesting impending doom ;p
  • Obligatory Goatze link. On second thoughts, let's not!

  • Live and let live. Black holes are people, too.
  • Those space cowboys aren't doing their job.

    Get to work, Spike.

  • by hack slash ( 1064002 ) on Thursday April 30, 2009 @07:15AM (#27770611)
    Take this wise lesson from Red Dwarf:

    "Well, the thing about a Black Hole, its main distinguishing feature, is it's black. And the thing about space, your basic space colour is black. So how are you supposed to see them?"

    *later on*

    "They weren't Black Holes."
    "What were they?"
    "Grit. Five specks of grit on the scanner-scope. See, the thing about grit is, it's black, and the thing about scanner-scopes..."
    "Oh shut up!"
    • by ledow ( 319597 )

      Swirly Thing Alert!

    • Re: (Score:3, Insightful)

      I vote for Buck Rogers to be remade like BSG, who's with me?

      A few years ago, I watched a cheesy rerun with Wilma posing as a hooker to sneak into some fat-cat's hotel room. Oh my! She was SMOKIN' back in the day! I just never picked up on that as a kid.

  • What about black holes NOT from the centre of galaxies? Fairly normal large (massive) stars end up as black holes too, so I'd expect a lot of black holes in this galaxy anyway, even if it hadn't interacted with any other galaxies.
  • I want these m*f*ng black holes off the m*f*ng galaxy!
  • Its obvious, that in order to be more eco-friendly and healthy, the central-black holes in democratically controlled galaxies have gone free-range to avoid contributing to universal warming. Its the damn republican black hole at the center of the Milky Way, sitting there, denying universal climate change that needs to be shown the error the of its ways. I say, lets raise taxes on republican black holes so that we can share the wealth and help the black holes in poorer, predominantly democratic galaxies be
  • by hyades1 ( 1149581 ) <hyades1@hotmail.com> on Thursday April 30, 2009 @08:09AM (#27770961)

    I'm reasonably sure there's one in my ex's purse. Money goes there to die.

  • by Anonymous Coward

    Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the drug store, but that's just peanuts to space.

  • Well, I would like to know, if a black hole comes by, does it actually pull a whole planet into its hole, do we know if this is possible...

    I mean at the core a small start implodes and turns into a black hole, but does it have enough strength to suck in another star, or even a whole solar system...and what happens if you put 2 black holes side by side, do they cancel each other out...sort of like putting a bag of holding inside a bag of holding...?

  • by jollyreaper ( 513215 ) on Thursday April 30, 2009 @09:23AM (#27771691)

    For the love of Christ, Republicans! You know that line about anti-zombie research? Don't fucking touch it! You saw what happened when you cut funding for volcano and pandemic flu research!

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