Talk:Stellar classification

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LBV is sometimes treated as a spectral type. Should it be added? Diamantinasaurus (talk) 12:39, 28 September 2024 (UTC)Reply

Again, I have noticed that the charts do not match in the temperature measurements. Could this be fixed eventually? @DVdm Youonlyliveoncehahahaahahah (talk) 13:38, 6 March 2025 (UTC)Reply

Thanks for your suggestion. When you believe an article needs improvement, please feel free to change it. We encourage you to be bold in updating pages, because wikis like ours develop faster when everybody edits. Don't worry too much about making honest mistakes—they're likely to be found and corrected quickly. You can always preview your edits before you publish them or test them out in the sandbox. If you need additional help, check out our getting started page or ask the friendly folks at the Teahouse. - DVdm (talk) 15:15, 6 March 2025 (UTC)Reply

This bold edit was already made. Unfortunately, it didn't match the given references, so I've reverted it. @Unmismoobjetivo: produced the chart, so either the chart needs to change to match the reference used in this article, or the reference used for the chart needs to be identified and possibly used to support the values in the table. Ironically, the one boundary that you didn't change (class O, 33,000->30,000) could be supported by the references. Some of the other values could arguably also be supported, but some definitely contradict the refs. Lithopsian (talk) 17:03, 6 March 2025 (UTC)Reply

Thank you for looking for those mismatches. I hope to update with the chart values soon. It should be removed from the page if there are significant errors. I should learn how to make the text editable, so that anyone can fix it. I will look into it further, thank you! Unmismoobjetivo (talk) 14:24, 21 March 2025 (UTC)Reply

I don't think the numbers can really be described as errors. There are many slightly-different values for the temperatures at spectral class boundaries. The only problem is the mismatches between numbers showing in different parts of the article and the references (are there newer ones, perhaps, that we could be using?), which could be considered confusing. Lithopsian (talk) 15:32, 21 March 2025 (UTC)Reply

There are some features missing from the list. For example, Aldebaran and 51 Pegasi have spectral types of K5+ III and G2V+, and the "+" is not included in the list. I don't know what it mean either. 21 Andromedae (talk) 19:59, 16 April 2025 (UTC)Reply

The plus sign is used to mean a number of different things. Off the top of my head:

• to indicate two spectra (probably two stars), eg. A5V + G0V
• to indicate a hypergiant, eg. B1 Ia⁺ (should always be a superscript, but sometimes typography doesn't allow)
• to indicate, perhaps confusingly, a star less luminous than normal for a luminosity class, most often a giant, eg. K0 III⁺ (originally a superscript, now often not)
• to indicate a non-integer spectral class increment, often interpreted as 0.5, eg. M3+ (often treated as M3.5)

Lithopsian (talk) 20:27, 16 April 2025 (UTC)Reply

Thanks. 21 Andromedae (talk) 20:43, 16 April 2025 (UTC)Reply

I was surprised to find the somewhat crude "Oh be a fine guy/girl, kiss me!" as the only cited mnemonic on the page. I looked for the one alternative given in the source given, but didn't find it, and Google showed me a few contests to find alternatives, so I removed the unsourced one and summarized that information instead.

Idk, I like kissing as much as the next girl (or guy), I guess I just find it a bit of an off-putting throwback. I did find that the Committee on the Status of Women in Astronomy held a contest in 1995 with the conclusion that the traditional one was best, as long as you could have "guy" as well as "girl". Publicly Visible (talk) 21:05, 10 June 2025 (UTC)Reply

The mnemonic dates from an era where people weren't reflexively offended - I learned a variant in the 1960s which included W, R N and S classes. With modern electronic assistants, the need for a mnemonic has largely faded into irrelevance. Tarl N. (discuss) 21:41, 10 June 2025 (UTC)Reply