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B What is the Great Attractor?

  1. Nov 22, 2016 #1

    I guess first I must ask, have we figured out exactly what The Great Attractor (TGA) is? This article seems to indicate we might.

    If not...

    Then I have two questions. We seem to know the approximate location and how much mass it must have and since it is hidden by an expanding slice the Milky Way hides from view we know it must fit within this slice. Therefore:

    1. Are there any other structures within the explored universe that would, if placed there, act like the TGA?

    2. If not, making the assumption that TGA is not a unique object, can it be explained by using any of the universe's known structures by making them denser?

    Thank you for your help,
    Last edited: Nov 22, 2016
  2. jcsd
  3. Nov 22, 2016 #2


    Staff: Mentor

  4. Nov 22, 2016 #3
    Thx so much for responding! I believe the article is newer then the wikipedia article. My primary questions follow...I'll assume you don't know. Actually no one may know unless they look around at the all the dense clusters we've found so far and go to the trouble of working it out but I thought I'd ask.

  5. Nov 23, 2016 #4

    jim hardy

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    Hmmm , if you'll pardon an amateurish question.....

    if we're that close to GA, and presumably accelerating toward it,

    might expanding universe be a backward conclusion from observed Hubble redshift , ie we're accelerating toward GA and away from distant stars rather than them accelerating away from us ?
  6. Nov 23, 2016 #5


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    That would not explain (and in fact would contradict) the fact that galaxies far beyond the GA but in the same general direction show a red shift indicating that they are receding from us at a very high rate.
  7. Nov 24, 2016 #6


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    I suspect the GA is merely an illusion once you apply the correct reference frame.
  8. Nov 24, 2016 #7
    This site is not listed as an acceptable source as detailed on the rules page. I don't see anything special about finding a bunch of new galaxies, this is very common in any direction we look.

    The first thing that comes to mind would be the origination point of the big bang, since the universe would end in a big crunch without the energy to drive expansion.
  9. Nov 24, 2016 #8


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    There is no such thing. Read some basic cosmology.
  10. Nov 24, 2016 #9
    I'm working on that. Wouldn't there be a center of mass building if the universe was collapsing in a big crunch?
  11. Nov 24, 2016 #10


    Staff: Mentor

    No. On cosmological scales the universe is spatially homogeneous; there is no "center", any point in space is the same as any other.

    The universe is not like an ordinary object, and the universe expanding is not like an ordinary substance like a gas expanding into a pre-existing empty space.
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