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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."

7 of 49 comments (clear)

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

    Merging Black Holes

  2. 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.

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  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.

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  4. 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.

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  5. 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 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.

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

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