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There's a Hole in the Middle of It All

Apparition writes "CNN is reporting that the star at the center of our galaxy is actually a super-massive black hole. The article then claims that it occupies a volume of space about 3 times that of our solar system. If my math is correct, about 230 million suns could fit into that same volume, so it doesn't impress me that the claimed mass of the black hole is only between 2.6 and 3.7 million times that of the sun. So what is up here? Since when do black holes occupy so much space (I thought they were points)? And how can something with a density only 1/100 of our Sun be called super-massive?" I think the article is talking about a maximum possible size of the object, due to limitations on the resolution of our instruments. Nature has a no-registration story about the research. Update: 10/16 23:44 GMT by M : There's an article with more information on space.com, and a press release from the European Southern Observatory.

4 of 572 comments (clear)

  1. What is Size? by BoBaBrain · · Score: 2, Redundant

    The size of the black hole isn't the volume taken up by its mass. It's the volume inclosed by the event horizion.

    If light enters that volume, it never(ish) gets out.

    --
    I am a Karma Library.
  2. Volume claimed shouldn't be for the hole itself by KoopaTroopa · · Score: 0, Redundant

    The matter in a black hole should be condensed down to a point. The event horizon is what would be many times as large as our solar system.

    Such an event horizon would take a whole lot of matter :)

    --
    Sharpies don't just sniff themselves.
  3. Event Horizon != Actual size by jimbo3123 · · Score: 2, Redundant

    The large size is probably the event horizon for the black hole.

    The event horizon is the sphere within which not even light can escape from the black hole. It is the dark area the the black hole appears to take up.

    The actual size of the object would be much smaller

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    There should be a moderation category "Dumbest Comment EVER"
  4. They're talking about... by john_roth · · Score: 0, Redundant

    the size of the event horizon. What's inside is unknown (and presumably unknowable)

    John Roth