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Galaxy splitting

  1. Aug 9, 2006 #1
    A question.

    Has there ever been an instance where a single galaxy split into two separate gallaxies or a recorded view where that would seem to be the case.

    Thank you.

  2. jcsd
  3. Aug 9, 2006 #2
    Randomly? No.
    Because of other galaxy's gravity?
    Yes. If the Milky way was put in the middle of two lager galaxies (but they are the same size) The galaxy would split, but not become a new galaxy, it would be eaten up. So the answer is no.
  4. Aug 9, 2006 #3
    Thank you Arian.

    It was in mind without interference from other galaxies. I was going to include (in my question) about the possibility of an event within the galaxy that was powerful enough to cause a split but I didn't want to muddle up the basic question.

  5. Aug 9, 2006 #4


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    The only thing that I can think of that might be able to do this is a starburst. Galaxies with a lot of star formation are observed to have large-scale outlfows of gas (presumably driven by supernovae). I suppose it's possible that some of the gas in these outflows could later collapse into a small galaxy, but I've never heard of anyone observing or modelling it.
  6. Aug 10, 2006 #5
    Thank you SpaceTiger.

    None of my research turned up anything even insignificant. At the size of some of these galaxies I'm always impressed at the far ranging effects of gravity that hold them together. If we could just figure out what gravity means.

  7. Aug 11, 2006 #6


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    No w that you mention it, Sunblock, it does seem posible, and even likely. Given the uneven distribution of matter in most gallaxies (i.e. the spiral arms in a spiral gallaxy), one would expect that the mass could be focussed aound not one but two centers of gravity, and these two could be at any locations, any distance from one another within the gallaxy. If enough gallaxies have this configuration, one could expect to find at least a few that rotated with enough angular momentum that these two centers of gravity were flung apart, breaking the entire gallaxy into two smaller ones.

    But AFAIK, it's never been observed. Unless that's what we're seeing here;

  8. Aug 11, 2006 #7
    Thank you LURCH.

    Logical and quite possible.

    I've always wondered if the spirals are locked in the gravity attraction one body to the next through the arms (all the way back to the core influence) or by the central massive gravity accumulation. Has the inertia overcome the core attraction so to speak. I use hurricanes as a high speed simblance of galaxy behavior and I've never heard of one splitting into two.

    Very interesting reference. Thank you

  9. Aug 11, 2006 #8
    It depends on how you define "splitting in two". We observe galaxies having massive amounts of gas stripped from them by the ram-pressure force of the intra-cluster medium as they fall into a galaxy cluster. Other effects such as tidal interactions are also known to strip matter from galaxies without the interacting galaxies ever coalescing.
  10. Aug 12, 2006 #9
    I don't think I would want to try and define it. Anywhere from a perfect 50-50 split to a full dusting. Anything (other than another galaxy) that can overcome the mass(read density) distance effect of gravity that would separate a sizeable amount of the galaxy from the main trunk would do I suppose. Whatever the condition of the separated material as long as it stayed fully separated.
    Last edited: Aug 12, 2006
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