Talk:Chromosphere

Needs rewrite

The only 2 sources listed here are basic websites. This page needs a major rewrite utilizing more sources. I've added the "need expert" tag. Jhay116 (talk) 19:53, 16 June 2009 (UTC)

To help improve this article, I have added 2 sources which may prove beneficial and a possible rewording of the third paragraph so the reader does not need to interpret the graph which may prove confusing and has outdated information. Feel free to reword or alter these changes. The content of this page also seems to be paraphrased from the text book cited, and the sections used are available for preview in google books, so anyone with the time to read through that section may be able to add some information to this page, or at least improve what is here already. Chrisfoster-NJITWILL (talk) 19:21, 2 May 2012 (UTC)

Google

The first five or so google-referenced pages for the search 'chromosphere' suggest it is actually 2000 or 2500km thick, not 'about 10000km'. Only this page gives this statistic. I'll leave it for now but some confirmation would be nice.--ChrisJMoor 02:11, 21 August 2005 (UTC)

yes, from the mean solar surface chromosphere is about 2500 km in height 14.139.190.82 (talk) 11:31, 25 April 2023 (UTC)

Original research

Photo taken by Luc Viatour during the French 1999 eclipse]]

Citations?

This page appears to list no formal citations from reliable sources (as of this note). Can someone please add some reliable sources to a section for References or citations? I think References is most commonly used? But it's been a while since I've actively edited... So, feel free to insert which ever method is the preferred method for listing sources. Thx, Mgmirkin (talk) 02:52, 17 January 2008 (UTC)

Spicules and fibrils

According to the article Spicule, spicules and fibrils are the same phenomenon seen from two different points of view (ie just like solar filaments and prominences). But the present article implies that they are two different phenomena.

Eroica (talk) 07:55, 20 January 2008 (UTC)

Wrong Numbers

If my Math Fu is worth anything at all, then 2.0 × 10^−4 : 5 000 000 is not 1.0 × 10^−11. Rather, the first value is 20 000 000 times as big as the other. The first paragraph might need a correction? — Preceding unsigned comment added by 91.23.94.95 (talk) 11:13, 22 August 2011 (UTC)

Comparing chromosphere and photosphere

I'm a chemist. I know what emission and absorption spectra are, but this section has me baffled. Quote:"Whilst the photosphere has an absorption line spectrum, the chromosphere's spectrum is dominated by emission lines." I am not familiar enough with the Sun's atmosphere to understand what the authors are attempting (and failing) to say. Is it that the gas/plasma in the chromosphere is cooling by emission? (And, if so, how is the energy being transferred INTO the chromosphere?). Are the absorption lines in the chromosphere faint because of the tenuousness of the gas present? Is it that the photosphere is so dense with so many emission lines that the principal feature of its spectra is absorption? Or is the emission not from electronic transitions in atoms/ions? Are the emissions frequencies extremely broad due to the large range of velocities and magnetic fields present, or something else? So IMHO characterizing one as having a emission spectra and the other and absorption spectra is not, without an explanation, very informative. I am confident that both emission and absorption are present in both regions, so the text's description is misleading at best. I am unsure how to fix this while retaining the valid (and useful) information present.216.96.77.46 (talk) 18:37, 14 November 2012 (UTC)

Chromospheric Activity Index (R′HK)

Should this topic be covered here or in a separate article? Praemonitus (talk) 19:27, 7 January 2016 (UTC)

Is this the place to cover the Mount Wilson S-index of chromospheric activity

Frequently mentioned in Observational evidence for enhanced magnetic activity of superflare stars so maybe it should be a separate article also linked from Superflare#Spectroscopic_observations_of_superflare_stars. [https://habitability.univie.ac.at/fileadmin/user_upload/k_habconf2016/pdf/poster/Mengel.pdf A small survey of the magnetic fields of planet-hosting stars] gives "Wright J. T., Marcy G. W., Butler R. P., Vogt S. S., 2004, ApJS, 152, 261" as a ref for s-index. I'll start it here for a redirect initially. - Rod57 (talk) 14:49, 21 December 2016 (UTC)

Lead image

• 
  Old image
• 
  New image

Hi all. Recently the lead image has changed back and forth a couple of times, and I would like to address this here. cc @MotloAstro and Artem.G:

I believe the old image is preferable because it is on-band. Dark mottles are very clear in the new image, indicating that it was taken in the H-alpha wing, not centered on the H-alpha spectral line. More simply, the chromospheric spicules emitting in H-alpha are less visible, showing photospheric granules underneath. (Compare with the GONG H-alpha images visible here and with the images at the end of the ref.) This is not ideal, since this is an article on the chromosphere, not the photosphere. Also, the disk is a lot brighter on the left in the new image, which is an artifact that may be misleading to readers. CoronalMassAffection (talk) 10:15, 15 December 2023 (UTC)

hey, I didn't know there were multiple changes of lead image, though I don't like the old image simply because of its poor quality. I found this flickr album by Kevin Gill with multiple photos in H alpha, maybe it has some better image that you think can work? Artem.G (talk) 11:20, 15 December 2023 (UTC)

or maybe this one from nasa Artem.G (talk) 11:33, 15 December 2023 (UTC)

and maybe MotloAstro can address the question of the new photo being off-band, I'm not an expert in the field. My main concern is that old photo is of so poor quality that jpeg artefacts are more prominent than actual sun features. Artem.G (talk) 12:12, 15 December 2023 (UTC)

and I just found that there is a commons category for sun in h alpha, where almost every image is better than current old one commons:Category:Sun by H Alpha light.

Sorry for many messages :) Artem.G (talk) 12:16, 15 December 2023 (UTC)

@Artem.G: No worries at all :) I have thought about this a little bit more, and I think it would best to use imagery from science-grade telescopes that we can be sure are centered on H-alpha. The series of GONG telescopes and BBSO's 10-cm telescope in particular come to mind. There are not many of these uploaded to Commons, so I have processed and uploaded a 2032x2032 BBSO image and replaced the current lead images with this. CoronalMassAffection (talk) 06:38, 3 March 2024 (UTC)

References