If a galaxy contains a super-massive-black hole at it's center.

Is there anything likely to be at the center of a super-cluster of galaxies?

Or to put it another way, are there likely to be any super-super-massive black holes, so massive that entire galaxies orbit around them?

  • 1
    $\begingroup$ By "center of a super-cluster" do you mean the super-cluster's center of mass? $\endgroup$ – N. Steinle Dec 31 '18 at 2:58
  • $\begingroup$ Well like a black hole in the center of a galaxy would be near the center of mass. $\endgroup$ – zooby Dec 31 '18 at 3:01
  • $\begingroup$ FWIW, the stars in a galaxy orbit the galaxy's centre of mass. The SMBH makes only a very small contribution to the total gravity of the galaxy (and of course not all galaxies have a SMBH in the centre). $\endgroup$ – PM 2Ring Dec 31 '18 at 3:50

The centers of galaxy clusters are usually dominated by a single massive elliptical galaxy (often called "brightest cluster galaxies" or BCGs). These galaxies contain their own central supermassive black holes, but these have the masses one might expect for their host galaxies, or in some cases a few times larger (i.e., several billion solar masses, up to a maximum of around 10 or 20 billion solar masses), not anything that scales with the entire galaxy cluster.

So, no, there's no evidence for "super-super-massive black holes".


"Is there anything likely to be at the center of a super-cluster of galaxies?"

Maybe we can say there could be a cluster which has a larger mass than the other clusters in the supercluster so that it attracts the other clusters itself. But it can't be any supermassive black hole.

First, we will need an enormous amount of mass so that galaxies can rotate around this mass. Let us think this idea, that may be a very very large black hole can do this. But we know that to create such a huge mass we need a star.

But as we can imagine stars should have a maximum mass limit to be stable. Hence we need a star that's so massive when it turns to the black hole it can rotate the galaxies around it. That not likely to be. Galaxies can have satellite galaxies but clusters do not turn around something.

On the Maximum Mass of Stable Stars.

Galaxies in the Superclusters don't need a massive black hole to stay together. They have DM and they are gravitationally bounded at most level.

But you might be interested in this, The Great Attractor

  • $\begingroup$ It is conceivable that an isolated large cloud of primordial hydrogen can collapse into a black hole of an arbitrary size. Is it not? $\endgroup$ – safesphere Jan 11 at 8:55
  • $\begingroup$ Well, we should have seen some sort of evidence for such a large black hole, As I pointed out that kind of a massive black hole would have a huge gravitational lensing effect. That kind of a black hole should have a mass of couple hundred galaxies maybe more. I am not much an expert, but that possibility seems unlikely. $\endgroup$ – Reign Jan 11 at 9:23

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.