Talk:Subgiant
From Wikipedia, the free encyclopedia
 | This  level-5 vital article is rated C-class on Wikipedia's content assessment scale.It is of interest to the following WikiProjects: | |||||||||||||
| ||||||||||||||
.jpg){kind=small}
Article moves
Taking a look at the 'what links here' for subgiant, it appears ALL of the wiki links are to the type of star. I am therefore moving the existing article from Subgiant to Subgiant (band), moving Subgiant star to Subgiant and disambiguating both. Modest Genius talk 15:52, 18 November 2006 (UTC)
Requested move
- The following discussion is an archived discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. No further edits should be made to this section.
The result of the move request was: Not moved. Jafeluv (talk) 09:46, 3 April 2012 (UTC)
Subgiant → Subgiant star – According to this CfD "subgiant" is ambiguous. Armbrust, B.Ed. Let's talkabout my edits? 13:08, 28 March 2012 (UTC)
- Oppose, why are you pluralizing articles? 70.24.244.198 (talk) 03:53, 29 March 2012 (UTC)
- Corrected. Armbrust, B.Ed. Let's talkabout my edits? 13:02, 29 March 2012 (UTC)
- Oppose WP:PRIMARYTOPIC. Headbomb {talk / contribs / physics / books} 12:23, 29 March 2012 (UTC)
- Oppose. Clearly this is the main meaning of the term, and CfD has absolutely no jurisdiction over article names. As it happens I agree that the category name is better with the 'stars', but that doesn't mean the article name would be. Modest Genius talk 23:46, 31 March 2012 (UTC)
- The above discussion is preserved as an archive of a requested move. Please do not modify it. Subsequent comments should be made in a new section on this talk page. No further edits should be made to this section.
Subgiant phase duration
What is the average duration of a subgiant phase for Sun-like stars compared to red giant phase? --Artman40 (talk) 00:04, 31 March 2013 (UTC)
- For a star like the sun, the subgiant phase is actually longer than the red giant phase! 2GYr is typical, less than 1 GYr for the red giant phase. Much of the time on the subgiant branch is spent very close to the main sequence while the hydrogen shell is slowly adding mass to the helium core. Once the core becomes degenerate the core temperature increases and the luminosity increases dramatically, so the time until the helium flash is relatively short. The opposite is true of more massive stars. Lithopsian (talk) 00:08, 25 April 2016 (UTC)
History
Some historical research has just been published on the early studies of subgiants . Might be a useful source for this article. Modest Genius talk 17:52, 17 May 2016 (UTC)
- Thanks for that, I hadn't seen this paper. Not quite the world-changer it is heralded as though. Those Mt Wilson subgiants were known and reported many years earlier, as mentioned in the article. The new news is really just that Gamow missed the opportunity to use them to redefine stellar evolution a decade earlier than Sandage did. It would be a good source if someone wants to write a detailed history section. Lithopsian (talk) 10:49, 18 May 2016 (UTC)
Properties
What is the source(s) of the data in the table? The linked source [8] does not contain these data unless I am mistaken. Tapeyhworm (talk) 18:43, 18 September 2021 (UTC)
- The evolution table? There are data tables included in the referenced journal. You may not see them if you just download a pdf or similar. Takes some digging, but the table here shows a handful of relevant data points. Lithopsian (talk) 16:53, 19 September 2021 (UTC)
Merge proposal
The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.
Proposing that Hertzsprung gap be merged into subgiant, specifically the "Mass 1 to 8 M☉" section. The Hertzsprung gap article is basically a dictionary definition, that might fit better as part of a larger article as opposed to a standalone one. Wormsward (talk) 12:41, 16 January 2026 (UTC)
- Support, but then I did make the suggestion in the first place, so I may be biased. Lithopsian (talk) 16:09, 18 January 2026 (UTC)
- Oppose (favouring expansion of current article) per WP:POTENTIAL. I've been thinking about this since proposing a WP:MERGEPROP over a WP:BOLD merger, and I think I lean towards keeping. Textbooks like KWW devote nontrivial page counts to the gap, and the current article -- while being little more than a dictionary definition -- has quite a bit it doesn't cover. I'll give improving the article a go over the next ~24 hours. MrSeabody (talk) 08:46, 19 January 2026 (UTC)
- Merge – It does seem too specific for a standalone article and fits nicely into the section proposed. FaviFake (talk) 12:29, 14 February 2026 (UTC)
Weakoppose. I feel that it should be kept separate as it describes an observed feature on the diagram (the map is not the territory), and it could be expanded with more history of science on the subject. But as is, it doesn't really stand on its own. If anywhere, Hertzsprung gap should be merged into a section on Hertzsprung–Russell diagram. Also, if merging into subgiant, I think it should rather merge into Subgiant#Subgiants in the H–R diagram (but I would in fact be more in favour of moving content from there onto Hertzsprung gap...) Slovborg (talk) 03:59, 21 February 2026 (UTC)- Comment. I was also going to write up on the Jao gap & the outcome of this here discussion als decides where it will fit: on the red dwarf page, on the Hertzsprung–Russell diagram page, or as standalone. Slovborg (talk) 19:01, 21 February 2026 (UTC)