The Naked Scientists

The Naked Scientists Forum

Author Topic: Clustered about Clusters  (Read 1279 times)

meta-sci

  • Guest
Clustered about Clusters
« on: 23/06/2009 08:33:34 »
Just an enquiry into the behaviours if galaxies within a cluster. As it is known(as far as we can safely say) that galaxies are all receding from each other. Are the galaxies within each cluster also moving away from each other? or is there a directionality of each galaxy within the cluster, of the cluster.


 

Offline Soul Surfer

  • Neilep Level Member
  • ******
  • Posts: 3345
  • keep banging the rocks together
    • View Profile
    • ian kimber's web workspace
Clustered about Clusters
« Reply #1 on: 02/07/2009 09:39:38 »
Galaxies in clusters are attracted to each other and not expanding significantly.  It is only on the very largest scales of gaps between the clusters of galaxies that the expansion dominates gravitational attraction  they move in sort of unstable orbits around each other altough there is a strong tendency for them to collide and clump together in the large galaxies that usually lie at the heart of the cluster.
 

lyner

  • Guest
Clustered about Clusters
« Reply #2 on: 02/07/2009 11:57:06 »
Despite the expansion of the Universe, we still ge pulled down to Earth all the time. Galaxies are in the same situation. It's all a matter of how much the local gravitational potential is, compared with how fast things are traveling. The Big gaps will be getting bigger but the Small gaps will be getting smaller. The net density is getting less, though.
 

The Naked Scientists Forum

Clustered about Clusters
« Reply #2 on: 02/07/2009 11:57:06 »

 

SMF 2.0.10 | SMF © 2015, Simple Machines
SMFAds for Free Forums