I'm not sure, whether there is any other observable super cluster like our local one, Laniakea, and if they do exists, do they also get pulled by the Great Attractor?

I am a little confused about superclusters and The Great Attractor, how they do exists relative to each other and how we can see/know from our galaxy, specifically from the Earth.

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    $\begingroup$ By definition, they aren't pulled to the Great Attractor. Laniakea is supposed to cover everything in one attraction basin. $\endgroup$ – Mithoron Jul 12 '18 at 23:28
  • $\begingroup$ Or more precisely, they are attracted, by our Attractor, but pull from other sources is stronger. $\endgroup$ – Mithoron Jul 12 '18 at 23:35
  • $\begingroup$ @Mithoron, So do you mean the Great Attractor is part of Laniakea? $\endgroup$ – Aung Satt Jul 13 '18 at 10:16
  • $\begingroup$ Of course, it's "deepest part" of attraction basin. $\endgroup$ – Mithoron Jul 13 '18 at 14:33
  • $\begingroup$ Just to add a link to the above. It says as much right on top: en.wikipedia.org/wiki/Great_Attractor We don't have a good idea what the Great Attractor is, because it's blocked by the densest part of the Milky way. en.wikipedia.org/wiki/Great_Attractor $\endgroup$ – userLTK Jul 13 '18 at 15:48

In short, not much gravitational pull at all, not relative to the distance and relative velocity.

Everything in the observable universe is gravitationally attracted to everything else, at least within the appropriate horizon. There should be some objects far enough apart, taking into account cosmic inflation, that gravity can't travel that far over the age of the Universe. For example the farthest galaxy we can see in one direction and the farthest one we can see in the opposite direction, those two galaxies can't see each other and they likely experience no gravitational pull from each other, but that's not really relevant to your question.

The Great Attractor is a comparatively small but very dense part of Laniakea, with an estimated mass thousands of times the mass of the Milky Way.

The Laniakea supercluster has a mass of about 100,000 Milky Ways, so any gravitational attraction one supercluster experiences would primarily be from other entire superclusters, and the great attractor would be a small percentage of that.

Superclusters experience gravity from other superclusters but the Universe is very uniform, so that gravitational pull is largely balanced out because it's coming from all sides.

This touches on one of the modern puzzles in physics, called the Horizon problem. This question goes back to the big bang and why the young universe was very close to, but not precisely uniform.

It might be a fun exercise to calculate the gravitational pull neighboring superclusters have on each other. I imagine it's pretty negligible compared to the expansion of space between them.

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  • $\begingroup$ Did you read my comments? All superclusters of Laniakea are in one attraction basin. Of course "Great Attractor" is only minor contributor to the attraction, but overall pull is making significant imbalance. Pull from surrounding clusters also isn't isotropic and whole Laniakea moves in one direction. $\endgroup$ – Mithoron Jul 14 '18 at 23:05

The method used to see the movement of galaxys relative movement to each other they measure the redshift of the galaxys http://hyperphysics.phy-astr.gsu.edu/hbase/Astro/redshf.html

I looked in to you question and found some answers for you in another topic on this site.Seems like the super cluster Laniekea is mowing towards the Great Attractor and accelerating as a whole at different speeds due to there diffrent masses. When will the Milky Way "arrive" at the Great Attractor, and what all happen then?

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