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Fast-Moving Black Hole

Posted by michael on from the vacuum-cleaner dept.

otisaardvark writes "New Scientist story about a very fast moving Black Hole in our very own Galaxy. Seems it was formed from a supernova explosion. I wish stars like this could have a more exciting name than GRO J1655-40 though. More at the BBC."

49 comments

  1. Here is more cool black hole news: by Neil+Blender · · Score: 4, Interesting

    Merging Black Holes

    1. Re:Here is more cool black hole news: by Anonymous Coward · · Score: 0

      Or on slashdot:
      Here.

  2. I wonder... by Daftspaniel · · Score: 1

    If we ever get close enough to one... does a Black Hole have any practical use? Or are they like potholes in the road? Great movie though - any sign of a DVD?

    1. Re:I wonder... by GigsVT · · Score: 5, Funny

      Yep, if we ever got close enough to a black hole, it would be the solution to global warming, corruption in government, freedom on the Internet, minority rights, energy production, and pretty much every other petty human problem you can think of.

      --
      I've had enough abrasive sigs. Kittens are cute and fuzzy.
    2. Re:I wonder... by Cs.Ender · · Score: 2, Interesting

      I can think of a couple ways to use a black hole to generate power. Rotating black holes have huge amounts of kinetic energy, and such a hole that had an electric charge could be used as a huge generator, if we could get an electric field large enough to surround it.

      The other method uses very small holes, about the size of a proton with the mass of a mountain. Due to Hawking radiation, such a hole would put out more power than a six nuclear power plants (if I remember the statistic).

      --
      I know lots of things. Most of them are wrong.
    3. Re:I wonder... by Santos+L.+Halper · · Score: 3, Interesting

      I've read that if you could get close enough to a black hole, and you threw something into it that was attached to a cord strong enough, the black hole will pull the matter into in, thereby pulling the cord, which in turn can be hooked to a turbine to produce electricity. The book (The Last Three Minutes) says that theoretically, you could get energy consistant with e=mc^2 this way.

      --

      "Ask not for whom the bone bones. It bones for thee." --Bender
    4. Re:I wonder... by JohnFluxx · · Score: 1

      This is just gravity. If you took a bit of rope with a wieght on it to the top of a bridge, and threw it down, you could use the moving rope to generate electricity.

    5. Re:I wonder... by NineBall · · Score: 4, Informative

      Black holes the size of protons would evapourate in seconds, due to the hawking radiation, and somehow I don't think you want to get too close to a large one. I'd love to see someone try, though, that would be a great stunt to see on Jackass.

      --
      You may not agree with what I'm saying but I'll kill you for my right to say it
    6. Re:I wonder... by 0x69 · · Score: 1

      If a large (star-like mass) black hole ever gets close enough to the solar system for us to seriously contemplate doing cool things with it, then the solar system will be destroyed without any wormhole, time-travel, super-electricity-generation or other cool things happening. Further, no technology we can plausably forecast could possibly let any humans survive the event.

      Executive summary: we ain't near old enough to play with this kinda toy.

      --
      It's easy to make up & spread cool- and credible-sounding stuff. Finding & checking hard facts is hard work.
    7. Re:I wonder... by Santos+L.+Halper · · Score: 2, Insightful

      Of course it is just gravity. The important thing is that it has *a lot* of gravity. Drop your weight from 1000 feet over a black hole (if you could get that close) and you'll get a lot more energy than if you dropped the same weight off a 1000 foot cliff here on Earth.

      --

      "Ask not for whom the bone bones. It bones for thee." --Bender
    8. Re:I wonder... by dunedan · · Score: 3, Funny

      except of course that ever present once we get inside cuasality could be violated and then your food keeps getting warmer and uncooking itself if you don't hurry up and eat it

      What a pain :)

    9. Re:I wonder... by Anonymous Coward · · Score: 4, Funny

      I think a black hole ate the periods in your sentences.

    10. Re:I wonder... by addaon · · Score: 2

      But you still need an infinite rope to get continual energy.

      --

      I've had this sig for three days.
    11. Re:I wonder... by Anonymous Coward · · Score: 0

      Just get the end of the rope as it comes out the other side of the hole.

      bring it around and tie the two ends of the rope together.

    12. Re:I wonder... by NoMoreNicksLeft · · Score: 2

      So use the energy to constantly build more rope onto its end, with some nanotech procedure.

      Don't think that even this allows for "perpetual motion", but could be fun all the same.

    13. Re:I wonder... by Anonymous Coward · · Score: 0

      He's right, guys. Discussion's over. Close this article thread.

    14. Re:I wonder... by Anonymous Coward · · Score: 0

      Eating periods...... thats disgusting

  3. THis is no time to joke. by Unknown+Poltroon · · Score: 4, Funny

    Your levity cant stand up under the gravity of the situation.

    yeah yeah, -1, bad puns.

    --
    All Troll + "offtopic" mods are meta moderated as "Unfair", because you abused the system.
  4. Time Travel by Merlin42 · · Score: 3, Interesting

    Im not so sure that this is really practical in the sense you meant, but just being near a large enough blackhole would provide a simple one way time machine (cf twins paradox).

    --
    Thoughts on tech, Software Engineering, and stuff
  5. Article is redundant by erpbridge · · Score: 0, Offtopic

    Sorry to tell ya, this article is redundant. It was reported in the Tranya-Voltaris Times about 6000-9000 years ago. I don't have a link, the page request timed out.

    Can't we get the Slashdot editors to post things on time a little sooner? I'm getting tired of the articles being a day, two days, or 6000-9000 years behind when they actually got posted.

  6. What should I believe? by Anonymous Coward · · Score: 0

    There are some contradictions of do black holes even exist. Black holes have many unsolved theoretical issues that keep them outside of my belief.

    Everything what's happening outside the hole sounds quite reasonable. But the stories of the world inside the hole are still quite awkward.

    ***
    *Little man

    1. Re:What should I believe? by NineBall · · Score: 3, Insightful

      Remember, in science, no theory is ever actually correct, merely proven to be beyond reasonable doubt.

      --
      You may not agree with what I'm saying but I'll kill you for my right to say it
    2. Re:What should I believe? by Cyno01 · · Score: 1

      *proves 'theory' of gravity wrong* Whee, i can fly!

      --
      "Sic Semper Tyrannosaurus Rex."
    3. Re:What should I believe? by NineBall · · Score: 1

      Now that would be fun, but somehow, I think that gravity does exist, oh wait, the cat's started flying again.

      --
      You may not agree with what I'm saying but I'll kill you for my right to say it
    4. Re:What should I believe? by Alsee · · Score: 2

      Remember, in science, no theory is ever actually correct, merely proven to be beyond reasonable doubt.

      Ladies and Gentlemen of this supposed physics journal..

      I have one final thing I want you to consider. Ladies and Gentlemen this is Chewbacca. Chewbacca is a Wookie from the planet Kashyyyk, but Chewbacca lives on the planet Endor. Now think about it, that does not make sense. Why would a wookie, an eight foot tall wookie, want to live on Endor with a bunch of two foot tall Ewoks? That does not make sense! But more importantly you have to ask yourself, what does this have to do with physics? Nothing. Ladies and Gentlemen it has nothing to do with physics! It does not make sense! Look at me, I'm a lawyer, defending the laws of gravity, and I'm talking about Chewbacca. Does that make sense? Ladies and Gentlemen, I am not making any sense. None of this makes sense. And so you have to remember when you're on that physics panel deliberating and conjugating the Principia, does it make sense? No! Ladies and Gentlemen of this supposed panel, it does not make sense! If Chewbacca lives on Endor you must acquit.

      The defense rests.

      -

      --
      - - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
    5. Re:What should I believe? by NineBall · · Score: 1

      *Head explodes* Oh, now look at what you've gone and done!

      --
      You may not agree with what I'm saying but I'll kill you for my right to say it
  7. Re:Black holes... by Anonymous Coward · · Score: 1, Funny

    Yes I can, if I ever meet you I may well throw you into one.

  8. Re:a Black Hole story without a goatse link? by Anonymous Coward · · Score: 0

    Simply put, I kill you!

  9. impossible speed without explosion ? by Anonymous Coward · · Score: 0
    400.000 km/hour ~= 111 km/s ... the earth moves at 30 km/s around the sun ...the inner planets moves even faster. The leonids at 71 km/s relative to the Earth ...

    The sun moves around the galatic center with a speed of 220 km/s

    Does anyone know why this speed could not be a result of two random objects had meeting each other ?

    The use of 400.000 km/hour instead of the usual unit of sounds like a poor attempt to make the numbers sound bigger ....

    1. Re:impossible speed without explosion ? by Anonymous Coward · · Score: 0
      400.000 km/hour ~= 111 km/s
      Whoa! Check your decimal place there Bub! There's 3600 seconds in an hour, not 3.6.
  10. This doesn't make sense to me. by Peter+T+Ermit · · Score: 4, Insightful
    Can anyone help me understand? Two problems:

    1) The black hole has a companion star, so wouldn't a kick of that magnitude tear it away from its companion and preclude it from acquiring another until it slows?

    2) Even ignoring the mass of the companion, the estimates are that the BH is about 7 solar masses. That means that the BH has acquired a kinetic energy of 1/2 * 7 * (2^30 kg) * (10^5 m/s)^2 = about 10^41 J of energy, which is about 1/1000 of the energy of the SN explosion (10^51 erg = 10^44 J). To me, that seems like an exceedingly large fraction of a roughly isotropic explosion converted into motion. It gets even worse if you throw in the mass of the companion.

    Anyone have any insights into how this can happen?

    1. Re:This doesn't make sense to me. by Anonymous Coward · · Score: 1, Informative

      Supernova lose about 10% of the mass of the final neutron_star/BH. In this case, final mass is 7 solar mass, so the energy released is 0.7 * solar_mass * c^2 which is about 10^54 ergs.

    2. Re:This doesn't make sense to me. by Peter+T+Ermit · · Score: 4, Insightful
      10^54 ergs would resolve a lot of the difficulty, but I thought that SNs couldn't produce anything much more than 10^51 or so ergs; anything significantly greater than that is a "hypernova" and is thought to have a different origin. (Or that the SN is beamed, which gives the illusion of higher energies.)

      Even so, I'm still confused about the companion, as the system's binding energy is probably rather less than its kinetic energy.

    3. Re:This doesn't make sense to me. by stonewolf · · Score: 3, Interesting

      Nice to see that this bothers people who have detailed understanding of the physics.

      Seems there are several problems unresolved questions here.

      Is the black hole moving with a campanion star? Or, just skimming off some mass as it passes by? If it is actually moving *with* the companion star, what kept them together? Assuming a SN explosion accelerated the black hole to 400,00 kph, how did it drag along another star? Even if they were a close binary pair before the SN explosion, wouldn't the black hole now have system escape velocity?

      Another question, how off balance does the explosion have to be to generate this kind of speed? If the explosion is 1% of balance, how much mass energy was released in the total explosion to get this speed? How do you get a SN explosion that is that off balance?

      Could this pair have been accelerated by another mechanism such as a close pass to a tight binary star system? How tight would it have to be? What kind of stars (neutron, black holes...) to get a pair with enough energy to speed something up like that?

      Like you said. this doesn't make sense.

      Stonewolf

  11. Let's check it out by Pastor+Fluff · · Score: 1

    We need to launch the Cygnus immediately! Paging Dr. Reinhardt...

    --
    Bubble, bubble, toil and trouble... can't we just go to Starbuck's for coffee?
  12. J1655 by suss · · Score: 2

    I wish stars like this could have a more exciting name than GRO J1655-40 though.

    Yeah, J1655 is such a jerky middle name!

    1. Re:J1655 by capnjack41 · · Score: 1
      more exciting name than GRO J1655-40

      How about the Oh Shit Everything's Getting Sucked Into It and We're All Gonna Die Star of Death?

  13. Obligatory Monty Python reference... by MAJ+Rantage · · Score: 1
    Just remember that you're standing on a planet that's evolving
    And revolving at nine hundred miles an hour,
    That's orbiting at nineteen miles a second, so it's reckoned,
    A sun that is the source of all our power.
    The sun and you and me and all the stars that we can see
    Are moving at a million miles a day
    In an outer spiral arm, at forty thousand miles an hour,
    Of the galaxy we call the 'Milky Way'.

    Our galaxy itself contains a hundred billion stars.
    It's a hundred thousand light years side to side.
    It bulges in the middle, sixteen thousand light years thick,
    But out by us, it's just three thousand light years wide.
    We're thirty thousand light years from galactic central point.
    We go 'round every two hundred million years,
    And our galaxy is only one of millions of billions
    In this amazing and expanding universe.

    The universe itself keeps on expanding and expanding
    In all of the directions it can whizz
    As fast as it can go, at the speed of light, you know,
    Twelve million miles a minute, and that's the fastest speed there is.
    So remember, when you're feeling very small and insecure,
    How amazingly unlikely is your birth,
    And pray that there's intelligent life somewhere up in space,
    'Cause there's bugger all down here on Earth.
    (Eric Idle & John Du Prez, The Meaning of Life)
  14. Cartoons Hold The Answer by Cyno01 · · Score: 2

    Did you ever see that one Pinky and the Brain? They created miniature Black Holes in a jar and sold them as garbage disposals, i don't remember how this tied into their plot to take over the world, bum bum bum... [insert theme song]

    --
    "Sic Semper Tyrannosaurus Rex."
    1. Re:Cartoons Hold The Answer by NineBall · · Score: 1

      The pinky and the brain,
      The pinky and the brain,One is a genius, the other's insane...

      --
      You may not agree with what I'm saying but I'll kill you for my right to say it
  15. woosh by Anonymous Coward · · Score: 0

    *hand goes over head*

  16. In Soviet Russia... by Cyno01 · · Score: 1

    Black Hole fastly moves you. And just about everything else in the vicinity...

    --
    "Sic Semper Tyrannosaurus Rex."
  17. not everyone use same notation .... by Anonymous Coward · · Score: 0

    400.000,00 km/hour

  18. Just thank your lucky stars... by Dr.+Cody · · Score: 1

    ...that he wasn't a goatse troll

  19. Crap. by grub · · Score: 2


    I've always liked the slow black holes. They come meandering towards you like a sloth and are easy to sidestep around.

    --
    Trolling is a art,