Clusters

• by Zebx

  Hi all, I was reading something about galaxy clusters but I didn't understand how I can identify what galaxies is part of a cluster. Thanks in advance 😃

  Posted July 31, 2016 10:21 PM

• by Budgieye moderator

  If the galaxies in a cluster have their redshift z meaured, and the distance between each member calculated and gravitational forces modelled, then a scientist might decide that it is a cluster. You can go into NED, and sometimes find labels of being a galaxy cluster, and find a scientific reference paper there that you can read. Otherwise we guess, going by colour or photoz and whether the galaxies show disturbance. I hope this helps.

  Posted August 1, 2016 10:12 AM

• by Zebx

  Yes thanks 😃 How this disturbance could be detected?

  Posted August 1, 2016 5:54 PM

• by Budgieye moderator

  If the galaxy is not symmetrical, or has tidal trails, it is likely to be disturbed. So just use your eyes and your judgement. There is no right answer, it is often a matter of opinion.

  Posted August 1, 2016 9:12 PM