Talk:Galaxy groups and clusters

A summary of this article appears in Galaxy.

Expansion

A list of members for each group and cluster is a good start, but I think it would be more useful to give distances and locations, plus maybe diameters. Anyone have access to that sort of information? My books are all back in Calgary. --Josh Grosse

All this information came from the internet. Article is a work in progress feel free to add information. Very difficult to find complete information for some of these groups. Mathew Carrier

Entropy

I think there is a better place for the entropy calculation somewhere else. It is not done correctly anyway. Oth (talk) 18:12, 3 March 2008 (UTC)[reply]

How does one calculate the number of galaxy groups or clusters? or super-clusters of galaxies? —Preceding unsigned comment added by Quaker phil (talk • contribs) 22:55, 13 October 2009 (UTC)[reply]

File:Galaxy.group.hickson.arp.500pix.jpg Nominated for speedy Deletion

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Proposal to merge Galaxy cluster into this page

There's really no need to have multiple pages on groups and clusters, as they differ only in size, and there's no sharp physical change. (Historically, clusters could be detected without redshift information, while groups couldn't, but almost all data today uses redshift information for cluster detection anyway.) It makes more sense to me to have a single article covering groups and clusters of all mass ranges. --Infophile ^{(Talk) (Contribs)} 19:01, 4 January 2012 (UTC)[reply]

Rhetorically speaking... by differing in size do you mean just by mass and not volume, or by both? The point is there are other differences; superheated gas exists in clusters but not in groups, to name one. Any merging of both articles will have to outline their similarities as well as their differences instead of simply copying and pasting both articles together (to whoever decides to do this, if it gets decided on). Here's an excellent starting point: [The Difference Between Clusters and Groups: A Journey from Cluster Cores to Their Outskirts and Beyond]. I'll hopefully be able to contribute, if I find the time. Tom.Reding (talk) 05:39, 14 February 2012 (UTC)[reply]

Either these articles should be merged into one, or there should be two separate articles - Galaxy cluster and galaxy group. It's confusing to have one article overlapping another. If a group is substantially different from a cluster, it should have its own article. --George100 (talk) 04:24, 4 June 2012 (UTC)[reply]

Galaxy subgroup, Galaxy subcluster

Galaxy subgroup and Galaxy subcluster redirect here, but aren't explained in the article. -- Beland (talk) 05:11, 13 October 2012 (UTC)[reply]

Caption for image of MACS J0152.5-2852 incorrect

the image for the article, a picture of MACS J0152.5-2852, a galaxy cluster - the caption states that almost every "pixel" in the image is a galaxy, while the details provided alongside the photograph clearly state that it's every "object" in the image that's a galaxy, which makes a lot more sense, as most pixels seen are in fact dead space or not in field of view.

meow <3 -jade 2600:6C47:A0F0:8390:B9D8:C97C:BD5A:512F (talk) 18:56, 8 July 2023 (UTC)[reply]