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Black Hole at Center of Milky Way

kwertii writes: "The Washington Post reports new evidence that there is a black hole with the mass of 2.6 million suns at the center of our galaxy. The Chandra X-Ray Observatory happened to be looking at the presumed site of the hole at the moment it absorbed a comet, blasting x-rays off into space as a byproduct. The implication is that the Milky Way is slowly spiraling down into a giant galactic drain..."

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  1. A small piece of basic physics by PD · · Score: 5, Informative

    I've noticed that some people have a bit of confusion here about exactly what the effects of a black hole are. Here's are examples:

    Q: What would happen to the orbit of the earth if all the matter in the sun were suddenly compacted into a black hole?

    A: Absolutely nothing. A black hole which contains the mass of the sun would still also have the same gravity as the sun. The earth would continue to orbit as it always has.

    Q: The galaxies stars orbit around the black hole.

    A: This isn't proven. Some galaxies don't have any evidence of a black hole, yet theirorbit around a center of mass. In any case, the black hole at the center of our galaxy is 2.6million solar masses. This is NOTHING compared to the billions of stars in the galaxy, so the effect of the black hole of the actual shape and orbit of the stars is not significant.

    Q: Doesn't it sound like someone has pulled the stats on this black hole out of their arse?

    A: Not really, the size of this black hole has been measured in several ways, including observing very high velocity stars near the black hole. The motion of these stars betrays the existence and size of the massive object at the galaxy's center.

    Q: Aren't black holes required for the formation of galaxies?

    A: We don't know for sure yet. There are galaxies without black holes, so it might not be required. Of course, we might just not be detecting the black holes that are in those galaxies.