Talk:Ultra diffuse galaxy

vs. Low-surface-brightness galaxy[edit]

What is their difference? LSBs are similar, low density galaxies. Or maybe this is a subtype of LSBs since they also have low surface brightnesses. SkyFlubbler ^(talk) 19:51, 19 May 2015 (UTC)[reply]

Wouldn't that depend on the mass density of the UCDs? LSBs have mass densities similar to luminous galaxies, but lower light densities. -- 65.94.43.89 (talk) 06:53, 29 May 2015 (UTC)[reply]

Good article to translate?[edit]

I see some minor flaws (redundant information), but it this in general a good written, reliable article to translate? -- Amtiss, SNAFU ? 20:12, 28 March 2018 (UTC)[reply]

Source?[edit]

What the source for the last sentece statement: "However, this study neglects the External Field Effect (an effect which does not exists in Newtonian gravity) which will change the internal velocity dispersion of a galaxy in MOND, making it conform with their findings." ?

For the sentence before it, I presume it refer to this paper: https://arxiv.org/abs/1803.10237 http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:1803.10237

182.253.163.72 (talk) 14:49, 29 March 2018 (UTC)[reply]

This also struck me as questionable. I have found sources regarding NGC 1052-DF2, for sure, but none of the ones I have seen have mentioned the external field effect. There seems little reason to leave in an unsourced statement that purports to challenge an actual source, such as https://www.nature.com/articles/nature25767 even if the editor in question is correct in their assertion that the study has flaws or the authors are in some way incorrect. If they are concerned about a study, then they should contact the authors or perhaps the journal in which it was published. If they want to contribute to the wiki article, then they should cite a reliable source which backs up their assertion. As things stand, even if the study in question "neglects the External Field Effect", we can not simply assume that the External Field Effect **will** explain any kind of discrepancy. Saying is one thing. Demonstrating is another. Thus why providing a source for such an assertion is important. 69.117.233.35 (talk) 16:35, 29 March 2018 (UTC)[reply]

Why no hyphen in name[edit]

Shouldn't it be ultra-diffuse galaxy (which redirects here) per the refs. - swap ? - Rod57 (talk) 01:15, 7 December 2021 (UTC)[reply]

The use in literature is a mixture of with hyphen, with space, or sometimes spaceless. I liked the no-hyphen the best, so I created it that way. Only about one article wants to link this with -. Graeme Bartlett (talk) 11:40, 7 December 2021 (UTC)[reply]