Talk:Rainbow/Archive 3

Snowbow
About the new section snowbow: Could this just be misstaken halos or fogbows? Either way it would be good to have a reference where the phenomenon in described either as how it occurs (what crystal shape is needed e.g.) or what it looks like (angle to the sun, width, color, preferably with an image). Ulflund (talk) 18:48, 27 January 2015 (UTC)
 * As the editor who added the new section.... "Snowbow" seems to cover a number of phenomena, certainly including halos, but some of the descriptions in the sources I found seem to describe something analogous to rainbows (i.e., arcs opposite to the sun's position). I'm still looking for more specific/technical references, and would appreciate some help! Dohn joe (talk) 19:14, 27 January 2015 (UTC)


 * This new section about the ill defined snowbow should be removed again because the author and the references all agree that it is not formed in raindrops. One of the references is by a meteorologist, Tom Skilling, who explicitly says that a 'snow bow' is formed in ice crystals (so it is a halo). The other two references, which suggest it is formed instead in 'snow crystals', are a travel guide and a dictionary. Last year someone posted a picture of a 'snow bow' on this talk page, which turned out to be an ordinary ice halo with sun dogs.  Ceinturion (talk) 00:30, 28 January 2015 (UTC)
 * I'd agree with Ceinturion here. Gandydancer (talk) 00:38, 28 January 2015 (UTC)
 * The question, though, is whether the phenomenon occurs opposite the sun, like a rainbow, as opposed to halos, which occur with the sun in the center. See also the discussion on my talkpage: User talk:Dohn joe. Dohn joe (talk) 01:26, 28 January 2015 (UTC)


 * Sure, feel free to investigate that question outside of this article. This article should contain solid knowledge about the rainbow, so I am going to remove the snowbow section now. Ceinturion (talk) 09:33, 4 February 2015 (UTC)

Thanks y'all for your contributions. It appears you are a knowledgeable bunch — would any of you care to look into my question regarding "true" vs. "false" moonbows here? Much appreciated! Drabkikker (talk) 15:16, 4 February 2015 (UTC)

Removed confusing statement
I removed the statement "Others suggest that Newton in fact called indigo the colour now called blue, and blue the colour now called cyan" because it is a confusing paradox. Newton said the bright sky is an excellent blue. The statement would imply that today we say the sky is an excellent cyan. Which is nonsense. Surely the indigo article is a better place to discuss or explain the paradox. Ceinturion (talk) 00:44, 27 February 2015 (UTC)

You tube video of double rainbow
I removed the paragraph about a "viral video" on you tube that shows some guy's "ecstatic reaction to a double rainbow" but the edit has been reverted. What's the fact that some Z-list celebrity starts yelling and shouting about a common optical phenomenon got to do with an encyclopedia article about rainbows? I've seen lots of double rainbows and there is even a picture of one in the lead. It would appear from the article about the video clip (I despair!) that the reason it went viral was because "comedian and late-night talk show host Jimmy Kimmel linked to the video in a post on Twitter, saying that he and a friend had declared it the "funniest video in the world." The video quickly gained over one million views". So it was nothing to do with the fact that the video showed a double rainbow. The fact that millions of people are interested in watching this guy make an idiot of himself doesn't mean it belongs in what is supposed to be a serious informative article and it does nothing to further our knowledge of the subject. Richerman   (talk) 18:47, 21 February 2015 (UTC)


 * I agree. That doesn't belong in this article. The reason the video went viral is not the rainbow. Ulflund (talk) 21:18, 21 February 2015 (UTC)


 * Seconded. I'll re-remove the section. Drabkikker (talk) 19:22, 27 February 2015 (UTC)

Anaxagoras
Anaxagoras could be mentioned. — Preceding unsigned comment added by 195.16.110.189 (talk) 17:16, 7 March 2015 (UTC)


 * According to this the only surviving fragment from Anaxagoras that deals with the rainbow is "We call the reflection of the sun in the clouds the rainbow". That's not enough. Ceinturion (talk) 13:46, 8 March 2015 (UTC)

Colors of rainbow count
Is the colors of the rainbow is 6 colors: red, orange, yellow, green, blue and violet (purple)? — Preceding unsigned comment added by 72.244.200.161 (talk) 09:57, 9 March 2015 (UTC)

Graphic not aligned with text and nature


The above graphic shows red as the inner most color whereas in nature and in the text red has the smaller angle i.e. less than 42 degrees, and is on the outside as can be seen on pictures of rainbows.


 * This is a common confusion, but the graphic is accurate. This video explains the concept nicely (starting from 1:20). Drabkikker (talk) 19:06, 14 June 2015 (UTC)

While the graphic may be accurate for a single ray of incoming sunlight, somewhere near 60° incident on the drop, the graphic (1) does not accurately explain anything about the formation of rainbows, (2) is only indirectly referenced in the article, and (3) that reference is not only hard to understand, it (4) does not explain the formation of rainbows in any way, only higher-order complications.

There are two thoughts about what causes rainbows in popular literature - and one is wrong. It sounds intuitive and doesn't require effort to understand, which is why it is popular, but it is completely invalid. It says that, after one internal reflection, any red light that exits the raindrop is at about 42° and any violet light that exits the raindrop is at about 40°. This is what the graphic in question suggests, and it needs to be removed from the article.

The real cause of rainbows is stated in the start of the paragraph that indirectly references the graphic, but it is stated incorrectly: "The reason the returning light is most intense at about 42° is that this is a turning point – light hitting the outermost ring of the drop gets returned at less that 42°." The incorrect part is "the outermost ring of the drop" - as I said, the turning point is light that is incident at about 60°. The graphic above the one in question here demonstrates this. I'm intending to re-write this paragraph, but I want to get prior cooperation before I do so we don't get into edit wars. The paragraph will explain that exiting light is brightest near the turning point, which is why colored bands appear. It will then explain that the turning point - not the exit angle for a single incoming ray - of each color is different due to dispersion. And finally, it will say that the turning point for violet is less than that for red, which is why violet appear below read in the rainbow. (This is actually not the best - the angle should be measured from the direction of the original ray, not the observation direction. The deflection angles are 140° for violet and 138° for red. But it is much easier to understand.)

This new paragraph will not try to explain effects due to the finite width of the sun (which the current one is correct about) or luminance not going to infinity (which it is not - luminance from any single point on the sun does go to infinity). JeffJor (talk) 12:12, 18 June 2015 (UTC)


 * Sounds like an appropriate improvement. I agree this topic should be addressed properly on the page. (Incidentally, the video I linked to above addresses it near the end, albeit in laymen's terms.) By all means go ahead! Drabkikker (talk) 20:57, 19 June 2015 (UTC)

No axial symmetry
The text mentions that there is an axial symmetry along the parallel sun rays. This is obviously wrong. Fixing any particular axis parallel to a sun ray clearly shows a lack of rotational symmetry. 212.88.6.19 (talk) 11:30, 13 July 2015 (UTC)


 * I'm not quite sure if I understand what you mean. Care to elaborate? Drabkikker (talk) 06:21, 14 July 2015 (UTC)

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Color order in secondary rainbows
The article currently says "Secondary rainbows are caused by a double reflection of sunlight inside the raindrops, and appear 10° outside of the primary rainbow at an angle of 50–53°. As a result of the second reflection, the colours of a secondary rainbow are inverted compared to the primary bow, with blue on the outside and red on the inside." This is incorrect. The number of reflections has nothing whatsoever to do with the order in which see the colors.

I've twice tried to correct it, with understandable text. Twice it has been reverted, with the claim that it was unintelligible. I suspect that it is because it contradicts commonly held, but incorrect, beliefs about how rainbows are formed. Specifically, So I'm going to try, once again. If you still think it is unintelligible, please tell me hear what it is you think is unclear so we can make it clearer to you. JeffJor (talk) 22:51, 25 April 2015 (UTC)


 * I'm going to revert for now. Please provide a source for your additions.  Thanks. Gandydancer (talk) 01:11, 26 April 2015 (UTC)


 * Thanks, Gandydancer. Sorry to say, JeffJor, but your edit (at least the second attempt) is not so much unintelligible as it is plain incorrect. I understand what you're trying to say with the whole "wrapping around the zenith" reasoning, but no such process is involved here. Please see http://www.atoptics.co.uk/rainbows/orders.htm. Drabkikker (talk) 09:14, 26 April 2015 (UTC)

Unfortunately, the formation of rainbows is a subject where some incredibly obvious-sounding explanations turn out to be inaccurate at best, and sometimes outright wrong. Expert explanations aimed at non-experts have to compromise between giving inaccurate impressions that match what people expect without being explicitly incorrect, and losing them in more exact detail. And Wikipedia editors need to understand how and when such compromises are made.

The site Drabkikker linked to does not say what you both see to think it says, it says what I did. And I used it as a reference in my first attempt - for the second, I was in a hurry. For example, the specific page that was linked only seems to say that each color of light in an Nth order rainbow follows only the path shown. What it omits is that these angles represent the minimum deviation angle in a wide range of angles, as properly described on http://www.atoptics.co.uk/rainbows/primrays.htm and http://www.atoptics.co.uk/rainbows/ord2form.htm. There are even sliders so you can show most of these paths.

I said "most" because the sliders don't let you take the original ray down to an incident angle of 0°. In the primary bow, that ray reflects straight back to the sun. This is a deflection angle of 180°, but the non-expert usage in the Wikipedia article calls it 0° ("The overall effect is that part of the incoming light is reflected back over the range of 0° to 42°"). The more detailed page in our reference calls it 180° down to "about 137.5°," the minimum deviation. This is where the colors are seen, but light from one reflection is seen at all of those angles. So the primary bow is a complete disk, not just the rim, and it's center is seen at a deflection angle of 180° (the anti-solar point).

The secondary bow's slider doesn't let you go anywhere near an incident angle of 0°; or even angles that end up away from the sun. But if you manipulate it you should be able to convince yourself that smaller incident angles do (it probably couldn't be programmed as easily). In fact, the deviations for the secondary bow go from 360° degrees (technically not 0°, it actually reverses twice) to a minimum of about 230 to 233°, as the reference describes in various places. It is also a disk, with its center on the sun. It wraps past the zenith (deviation 270°, just beyond the range of the slider), all the way to deviations 230° to 233°. Red deviates least (230°, seen at 50° when looking away from the sun),which is on the OUTSIDE of the disk. It just seems to be on the inside. JeffJor (talk) 14:46, 26 April 2015 (UTC)


 * Alright. It seems we're both looking at the same phenomenon in very different ways. I follow your reasoning and I'm willing to be proven wrong, but could you provide any sources, other than the page at Atmospheric Optics, which we both appear to interpret differently? Drabkikker (talk) 20:12, 26 April 2015 (UTC)

With no disrespect intended, I'm looking at it from the point of correct physics, and you seem to be looking at it from the point of folklore that you don't want to accept is incorrect. Many of my references are textbooks, which don't try to explain it the same way - just teach. So they don't spend much time describing what is seen, but you can get that from the equations. The one I like is http://www.trishock.com/academic/rainbows.shtml. Or http://www.cems.uvm.edu/~tlakoba/AppliedUGMath/rainbow_HallHigson.pdf.

The summary is that when the original incident angle is A (all angles from 0 to 90 are present), light enters the drop at angle B=asin(sin(A)/k) where k is the index of refraction. It deflects (A-B) as it enters, (180-2B) at each reflection, and another (A-B) as it exists. This makes the net deflection after N reflections D(A,N) = 180N + 2A - 2(N+1)B. Try plotting it, if you want - just don't truncate it to a range of 360 degrees.

When A is 0, D=180N which is the "center" of all the reflected light. It is the anti-solar point when N is odd, and the sun when N is even. As A increases, D decreases for a while until it hits a minimum. The light becomes highly concentrated at the minimum deflection angle. Since each color has a different minimum deflection angle, colored bands appear. Red is always the "lowest" minimum, so it is always "inside" and is the only monochrome band. All the others are mixes of lower-frequency colors, that are perceived as the color of the concentrated light. Inside the violet band, it doesn't stop - it simply fades to white. This means that the rainbow exists "inside" the colored bands, as white light. Alexander's Band is the absence of this white light. JeffJor (talk) 23:51, 26 April 2015 (UTC)


 * Thanks for your reply. No disrespect meant here either, and I apologize for calling your explanation incorrect earlier. It took me a while to wrap my head around the concept, but I now understand what you are saying. Yes, I was aware of the fact that rainbows are disks rather than mere bands, it just never dawned on me that the secondary rainbow is a "negative disk", so to speak. That's actually very interesting, and I thank you for broadening my mind! Perhaps it's useful to add the references you gave to the Wikipedia page. Even so, couldn't we still maintain that the color reversal (or the apparent reversal, if you wish) of the secondary bow is the (indirect) result of two internal reflections? Drabkikker (talk) 04:53, 27 April 2015 (UTC)

"Wrap my head around the concept" ? Pun intended?

There are many "folklore" explanations of rainbows: "Colors are created by the physical separation (implying isolation) of colors." No, they are caused by the concentration of each color in a different place, causing it to dominate over others. "Think of the raindrops as prisms." A lens, or a flashlight's parabolic mirror, is a much better analogy. "They occur at the specific angles where total internal reflection occurs." Not only is TIR unrelated, it is impossible. "Colors are reversed in the secondary because the additional reflection inverts the order." Again, with no disrespect intended, these incorrect statements seem so obviously correct, that they are almost universally accepted as true. Most explanations that recognize the differences will still use what I call "fuzzy language" that allows those who believe these untruths to continue doing so. If they didn't, they would be disbelieved just like you did. I even expected it here. So colors are explained by "separation of colors," which is true, but not the way people will assume the term implies.

Can we still maintain that the color reversal is due to two reflections? Almost. We can also maintain that day and night are caused by the sun moving in a circle around the Earth. In fact, that is a better explanation, since motion is relative and the true cause - Earth rotation - can always be translated into equivalent orbits. The same isn't true for color order. Find a liquid whose indices of refraction for violet and red light, respectively, are 1.15 and 1.13. The primary rainbow will be between 79.2° (violet) and 85.2° (red). The secondary will be in the same direction between 13.7° and 23.9°. The order is the same, because the secondary disk will wrap around the anti-solar point as well. And while it is hypothetical, for the indices I use for water (1.344 and 1.331), the odd/even=inside/outside ordering changes around the 12th or 14th order rainbow. JeffJor (talk) 12:00, 27 April 2015 (UTC)


 * Understood. Thanks once more! (As for the pun, it wasn't so much intended as serendipitous ;)) Drabkikker (talk) 19:02, 27 April 2015 (UTC)

This section is confusing "Secondary rainbows are caused by a double reflection of sunlight inside the raindrops, and are centered on the sun itself. They are about 127° (violet) to 130° (red) wide. Since this is more than 90°, they are seen on the same side of the sky as the primary rainbow", in particular "centered on the sun itself" and "Since this is more than 90°, they are seen on the same side of the sky as the primary rainbow". I'm a physicist and can't figure out what is trying to be said! Jeromeg52 (talk) 16:51, 9 January 2016 (UTC)JeromeG52


 * Yes, it took me a while as well (see discussion above). What JeffJor is trying to say is: From a physics viewpoint, the secondary rainbow is a disk centered on the sun. However, because its radius is larger than 90°, its rim ends up on the other side of sky as where the sun is: it forms an "inside out" disk there, if you will. The primary rainbow is also a disk, but centered on the antisolar point. Because its radius is smaller than 90°, this means it stays on that side of the sky, forming a "normal" (i.e. "inside in") disk. It just so happens that the two disks almost meet there, causing what we call a double rainbow. Drabkikker (talk) 19:13, 9 January 2016 (UTC)

Thanks Drabkikker, could your more complete explanation be incorporated into the article? Jeromeg52 (talk) 22:31, 17 January 2016 (UTC)JeromeG52


 * I might, but since JeffJor has announced to rewrite the section on this topic, perhaps it is better to await that without me interfering. Drabkikker (talk) 10:34, 20 January 2016 (UTC)

Twinned rainbow
I made a new summary of the ray tracing study that explained the twinned rainbow. The purpose of the authors was not to explain the twinned rainbow, but to evaluate their new software for nonspherical droplets. Unfortunately, their droplet shape model seems to be an unvalidated extrapolation of a shape model for larger droplets (>1 mm). Ceinturion (talk) 18:36, 19 January 2016 (UTC)

Strange: downloading the article from the link somehow seems to be browser dependent: successful for Chrome, but unsuccessful for Edge and IE. The images in the article are the problem: they are downloaded only partially by Edge. Ceinturion (talk) 18:36, 19 January 2016 (UTC)


 * I read up on this quite a bit when we first entered it. At the time it seemed quite promotional to me...but I was not sure...  I'm afraid that I'm not much help... :)  Gandydancer (talk) 19:10, 19 January 2016 (UTC)


 * In addition, what I don't understand about the explanation in the article is: why has the vertical motion of the top of the rainbow never been reported for 'normal', non-twinned, rainbows? I imagine the droplet size always varies when a shower is developing or passing by. According to figure 13 in the article, the rainbow top descends 6° if the droplet size increases from 0.40 to 0.50. That is so much that vertically moving rainbow tops (untwinned) should have been reported occasionally by observers. Ceinturion (talk) 21:29, 19 January 2016 (UTC)


 * Perhaps this is simply explained by the fact that the human eye is not very well equipped at estimating how perfectly round a circle is, especially if there is nothing to measure the circularity against. Also, our brains tend to minimize horizontal flattening more than vertical, as illustrated by rotating a picture of a sunset 90°, suddenly making the flattening of the solar disk much more pronounced than in horizontal position. Then again, 6° does seem quite a lot not to be noticed. Drabkikker (talk) 10:30, 20 January 2016 (UTC)


 * The eye would not need to be very well equipped if the top of the rainbow happened to be near a tree, a building, or the horizon. Ceinturion (talk) 17:28, 20 January 2016 (UTC)


 * Hmm, not so sure about that. That would still require knowledge of where the arc should be expected if it were perfectly circular, in order to deduce how much the observed arc deviates. Since we don't know (at least not without angle measuring devices) where exactly that "perfect" arc is supposed to be in the sky, the unaided observer has nothing to measure any deviation by, other than rough estimates based on the shape of the rest (i.e. left and right "legs") of the bow, which I imagine would provide a rather poor clue. This only gets worse if its top is near the horizon, considering most of the bow would then typically be invisible. Drabkikker (talk) 19:02, 20 January 2016 (UTC)

Semi-protected edit request on 19 March 2016
The color indigo is not on the spectrum anymore due to confusion between blue and violet. This page is outdated by more than 15 months.

108.18.150.171 (talk) 11:43, 19 March 2016 (UTC)


 * Your request does not conform to the required format. Drabkikker (talk) 12:39, 19 March 2016 (UTC)


 * Ignoring the fact that the correct format for the template has not been used by a relatively inexperienced editor, there is clearly a point to be answered here. I don't know what you mean about 15 months (people have been arguing that there is no indigo for a longer than that) but the colours named in the spectrum are fairly arbitrary and Newton went for seven for mystical reasons. There is a continuous change from blue to violet, so whether you call some of the blue "indigo" is a matter of choice and there is no real agreement about it - see and .  Richerman    (talk) 02:38, 20 March 2016 (UTC)

Position of colour within the rainbow
Perhaps there could be some explanation as to why yellow is at the central point of a rainbow. Thanks. 86.157.196.130 (talk) 09:05, 2 November 2016 (UTC)
 * Coincidence, really. Yellow shades just happen to lie roughly in the middle of the solar spectrum. Drabkikker (talk) 11:02, 2 November 2016 (UTC)

Semi-protected edit request on 4 November 2016
My request is to have the number of colors changed from seven to six. I believe as Issac Asimov stated, that Indigo is merely dark blue. It can be easily argued that there is a darker red, orange, yellow and so forth. The fact that Newton started with five colors, missing orange, and then jumped to seven leads me to speculate that when confronted with the missing orange, Newton, not to be out done, includes Indigo just for spite! Well I vote six colors, lets use our eyes to judge how many colors there are, and not believe, so easily, people that spend to much time sitting under coconut trees.

Tnx :)

Jelbog (talk) 08:50, 4 November 2016 (UTC)
 * ❌ this is not a vote - and we do not speculate - we report what the majority of reliable sources already state - Arjayay (talk) 10:31, 4 November 2016 (UTC)

Semi-protected edit request on 7 April 2017
CHANGE LINK FOR NOTE 10: Hutchison, Niels (2004). "Music For Measure: On the 300th Anniversary of Newton's Opticks". Colour Music. Retrieved 2006-08-11. FROM http://home.vicnet.net.au/~colmusic/opticks3.htm [OLD INACTIVE LINK] TO http://www.colourmusic.info/opticks3.htm [PRESENT ACTIVE LINK 2017-04-07] Nielshutch (talk) 13:10, 7 April 2017 (UTC)


 * Done! Drabkikker (talk) 14:42, 7 April 2017 (UTC)

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Semi-protected edit request on 27 July 2017
In the External Links section, the link for "Rare photo of the ‘end’ of the rainbow" is no longer available. Request to remove this entry. — Preceding unsigned comment added by Shr2012 (talk • contribs)
 * Yes check.svg Done DRAGON BOOSTER   ★  09:48, 27 July 2017 (UTC)


 * Pretty ridiculous item in the first place. Drabkikker (talk) 11:42, 27 July 2017 (UTC)

Semi-protected edit request on 31 July 2017
Please, fix an image link in the Experiments section. The square brackets are missing in the link. ThermIt (talk) 12:46, 31 July 2017 (UTC)


 * I deleted info about another photo. How's it now?  Gandydancer (talk) 13:04, 31 July 2017 (UTC)
 * Looks good to me. I'll mark this request as answered now. jd22292 (Jalen D. Folf) (talk) 15:14, 31 July 2017 (UTC)

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Semi-protected edit request on 10 December 2019
May I add this photo to the page? https://commons.wikimedia.org/wiki/File:ROGUE_VALLEY_RAINBOW.jpg EricFoy (talk) 19:50, 10 December 2019 (UTC)
 * Red question icon with gradient background.svg Not done: it's not clear what changes you want to be made. Please mention the specific changes in a "change X to Y" format and provide a reliable source if appropriate. Interstellarity (talk) 23:38, 10 December 2019 (UTC)
 * Hi there Eric, sorry to say but I don't think we should add this photo. I've worked with the article for a long time, long enough to learn that there are many, many good rainbow photos but we must limit what we put here - and I'm one of those that likes lots of photos.  We had a gallery for awhile but it was a constant problem with people adding the photo they just took and deleting other very good ones, etc., etc.  We've already got a double bow with the inner color bow  as well so we don't need two of them. Sorry.  Gandydancer (talk) 00:10, 11 December 2019 (UTC)

Spectrum Rainbow with Roy G. Biv mnemonic
It appears from the talk and history of this article, that it's pretty much agreed that it contains plenty enough pictures. However, the rainbow is often depicted in its 7 spectrum colors, as shown in the pictures below. Also, the Roy G. Biv mnemonic is often used as an aid to remembering the order of the spectrum colors.

Here is an image of a spectrum rainbow, with gradients between adjacent colors, and the Roy G. Biv mnemonic.



— Preceding unsigned comment added by Brandenads (talk • contribs) 05:12, 29 May 2020 (UTC)

New paper on triple split rainbows and raindrop oscillations
If you are interested: https://www.osapublishing.org/ao/abstract.cfm?uri=ao-59-21-F2095.90.239.226 (talk) 18:43, 12 June 2020 (UTC)

Why are the languages on the sidebar not in alphabetical order?
I was trying to find the Chinese (Zhongwen) version of this article, and I noticed the sidebar languages are not in alphabetical order? What's up with that? — Preceding unsigned comment added by Traversetravis (talk • contribs) 01:06, 12 July 2020 (UTC)

Can an expert ID supernumary or twinned rainbow?


I thought at first supernumary, but then noticed that the colors seem to repeat in the same order and get wider as it gets higher. Can anyone confirm Twinned rainbow? Elf | Talk 21:21, 13 May 2020 (UTC) My opinion is that these are well developed supernumeraries, but not a twinned rainbow. The twinning occurs near the top, and the branches look nearly identical, with only some possible differences in brightness. 95.90.239.226 (talk) 18:43, 12 June 2020 (UTC)


 * (I do not see the twinning as only at the top) My uneducated guess is a twinned rainbow.  It sure would be good to get a real expert here, wouldn't it?  Gandydancer (talk) 19:32, 12 June 2020 (UTC)


 * OK, I reviewed our article and I agree that it is not a twinned bow. However during my reading of our article I found this added on at the end of the section:


 * Meanwhile, the even rarer case of a rainbow split into three branches was observed and photographed in nature.


 * So I looked at that site and at the photo and I believe that it is a twinned bow with second "normal" bow--as our twinned bow section suggests does happen at times. What do you think?  Gandydancer (talk) 09:41, 15 June 2020 (UTC)


 * I myself added this note to the article and I also wrote the blogpost behind the link. Here is another one: https://atoptics.wordpress.com/2019/06/27/a-multi-split-rainbow-from-south-east-china-august-12th-2014/ My motivation was to make these very rare cases of triple rainbows better known to the public (there is still new physics to discover in the good old rainbow!). The new Applied Optics paper discusses how drop oscillations can make such triple bows happen. But they are not the best examples for the "medium rare" twinned bows (with two branches) as they represent some exceptional advanced stage of the phenomenon. Here are some more typical pictures: https://www.meteoros.de/bildergalerie/?no_cache=1&snipe_gallery[cat]=90 (full link ends behind "90"). 95.90.239.226 (talk) 19:01, 15 June 2020 (UTC)


 * The extra arcs in Elf's photo seem to be concentric with the primary arc, so I do not think they are twinned rainbows. Ceinturion (talk) 16:39, 16 August 2020 (UTC)

Asimov quote on indigo and being included in table of colours
I deleted the Asimov quote and his colour schema from the table in the section Number of colours in spectrum or rainbow.

The reason for my doing so is that Asimov is not any sort of authority in this area (unlike Newton). He is simply a science fiction writer and a popular science writer, neither of which make his personal opinion on indigo worthy of inclusion in this section. Gandydancer who reverted me said that his opinion was 'interesting'. Perhaps some might find his opinion interesting (I don't) but a personal opinion by someone who is not a subject authority does not merit inclusion. Oska (talk) 14:30, 15 August 2020 (UTC)


 * Hi there. I certainly do see your point and I hoped you'd post.  What I did was to try to delete Asimov  from the visual presentation but to no avail--my skills are pretty limited.  Would you agree to that while we leave the wording in the article?  Gandydancer (talk) 14:40, 15 August 2020 (UTC)


 * Hi Gandydancer. My first intention in editing was actually to remove Asimov's schema from the table because that is certainly undue weight (putting him on the same level as Newton). But then I saw the Asimov quote too with a full paragraph given to it and thought that was not worthy of inclusion either. I note your point about his quote being included in the article on Indigo but I see it as being more relevant there, as an example opinion on Indigo. However giving a whole paragraph to Asimov's opinion on one colour of the rainbow in an article about rainbows still seems to me undue weight and, essentially, trivia. So sorry, I'll hold to my opinion that all of the Asimov material should be excised. But happy to wait for some third party to weigh in. Oska (talk) 14:51, 15 August 2020 (UTC)
 * OK, I'm fully open to other opinions. One thing I'm in total agreement with is removing him from the table presentation. I'd agree that there is no question but that it needs to go...and please do remove it.  Anyway, not too many watch this article but there are a few good ones...we will wait and see...  Gandydancer (talk) 15:00, 15 August 2020 (UTC)


 * Have re-removed Asimov from the table. Oska (talk) 04:55, 16 August 2020 (UTC)


 * I agree with removing the Asimov quote. I think it is unfortunate that Asimov, and the cyan/blue/indigo controversy, are in this rainbow article. True rainbow colors are something else than pure spectral colors. Although in common speach the word "rainbow" may be employed for a pure spectrum, it is wrong and confusing from a physics point of view. True rainbow colors are variable, dependent on the droplet size, and they are a blurred version of the spectral colors. The cyan/blue/indigo controversy may have some meaning when discussing, somewhere else, the invariable pure spectral colors, but not when discussing true rainbows.  Ceinturion (talk) 11:35, 16 August 2020 (UTC)


 * OK, it should clearly go. It is so uplifting to work with such good editors.  Gandydancer (talk) 12:24, 16 August 2020 (UTC)


 * Appreciate your gracious collaboration Gandydancer and thank you for your input Ceinturion. As we now seem to have agreed on the removal of the Asimov quote I'll go ahead and do it. Oska (talk) 02:06, 18 August 2020 (UTC)

Say, while there are a few people around, do you two (and others) think this is a twinned bow (as discussed above)? Gandydancer (talk) 12:40, 16 August 2020 (UTC)

image of "rainbow sky"
This is a photo published by the US National Park Service of a musk ox with what they called "rainbow sky" in the distance. Not sure what this would be classified as but I thought it was an amazing image so thought I'd post it here to see if thee's interest in adding it to the article. Beeblebrox (talk) 22:12, 12 September 2020 (UTC)

Dark double rainbow photo
I think the new "dramatic" photo of a double rainbow photo at dusk is unrealistic, and therefore not suitable for wikipedia. The description says "at dusk". However, the center of the rainbow circle is about 20° below the horizon, so the sun was 20° above the horizon. So this is during the daylight, not at sunrise or sunset, and the photo is artificially dark due to a short exposure time or photo editing. This photo does not show to what a human observer would have seen. Ceinturion (talk) 09:37, 19 September 2020 (UTC)


 * Thanks, I reverted back to the previous pic. I thought it seemed very odd that such a thing could happen but I noted that an editor said it was his own work...  They can respond here if they wish.  Gandydancer (talk) 15:40, 19 September 2020 (UTC)


 * I think File:Full featured double rainbow at Savonlinna 1000px.jpg is a clearer image of a dounbe rainbow rather than File:Double-alaskan-rainbow.jpg. What do you think? Seth Whales   talk  09:49, 22 November 2020 (UTC)


 * I think you are right(though I hate to see the old one go!) Gandydancer (talk) 13:30, 22 November 2020 (UTC)


 * I like the old image in the introduction because of the shadow of the photographer's head on the bottom marks the centre of the rainbow circle (antisolar point), and because of the presence of a waving person in the center. The introduction is not about the secondary rainbow, that aspect is discussed elsewhere in the article. Ceinturion (talk) 23:10, 22 November 2020 (UTC)

Citations, neutrality, history, and culture
This article lacks a significant amount of citations throughout, especially in the introduction. The scientific history section lacks proper citation, lacks neutrality, and does not fully explain previous scientific views of the rainbow. Lastly, has anyone considered removing the section on culture given that it has its own main article? Ash Worley (talk) 18:04, 19 February 2021 (UTC)
 * Per WP guidelines the lead does not require sourcing for similar articles. As always, please add any new sources that you can find but you will need to be very specific about your lack of neutrality suggestion so that we will know where we may need to do some work.  As for the culture (and mythology) section, articles generally do include a smaller amount of copy when they refer to the more complete article.  Gandydancer (talk) 18:28, 19 February 2021 (UTC)

Rainbows in black and white photographs
"[N]o banding of any type is seen in a black-and-white photo of a rainbow, only a smooth gradation of intensity to a maximum, then fading towards the other side."

Could we get a citation on that particular statement? It's got to be supported by an actual source; simply showing the viewer a black-and-white rainbow photograph and saying "See for yourself" would be original research. I'd be more than happy to see one or more black-and-white rainbow photographs on the page for explanatory value (perhaps the same photo in color side-by-side with the BW) but the claim itself has got to be found in an external citation. 196.11.159.111 (talk) 10:31, 5 March 2021 (UTC)

Upper cased Sun and Earth
Many uses of the word 'sun' and 'earth' on the page are actual proper name mentions of the Sun and Earth (capitalized per Wikipedia style). My edit upper-casing these examples was quickly reverted, citing the same guideline. Please go over the edits and upper case Sun and Earth when used as proper names for the star and the planet, thanks. Here's the first lead example where Sun should be upper-cased, per Wikipedia style, and was reverted: "Rainbows caused by sunlight always appear in the section of sky directly opposite the sun." Earth was reverted in this sentence "From above the earth such as in an aeroplane..." which references the planet and should have remained upper-cased, as should Earth in the sentence "...the flood story of Noah, where it is a sign of God's covenant to never destroy all life on earth with a global flood again." There already are numerous instances in the article in which 'Sun' and 'Moon' are correctly upper-cased, so per page consistency the other proper-name solar and planetary mentions should also receive capitalization. Randy Kryn (talk) 12:58, 23 February 2021 (UTC)
 * So sorry to put you through all this trouble. I (wrongly) thought that we had been through this before and what we had was currently correct.  I reverted my edit.  Gandydancer (talk) 17:12, 23 February 2021 (UTC)
 * Thanks. We both acted in good faith, so just Wikipedian's collabing. Check out the category I put up yesterday, Category:Rainbows in art, which I why I came poking around here in search of more artworks. Randy Kryn (talk) 17:46, 23 February 2021 (UTC)


 * I think that the recent edit needs to be reverted. Per MOS:


 * The words sun, earth, moon and solar system do not take capitals in general use (The sun was over the mountain top; The tribal people thought of the whole earth as their home). They are capitalized when the entity is personified (Sol Invictus ('Unconquered Sun') was the Roman sun god) or when used as the name of a specific body in a scientific or astronomical context (The Moon orbits the Earth; but Io is a moon of Jupiter).


 * For example sun has been changed to read: "...the observer is at a spot with clear sky in the direction of the Sun."  Sun should not be in caps here.  Gandydancer (talk) 16:21, 5 March 2021 (UTC)
 * I capitalized it because it seems "in the direction of the Sun" means to indicate where the actual star is in the sky astronomically. That was my reasoning for that one edit. I do scan the meaning of each change and am careful of not capitalizing items, for example, which mean 'sunlight' when saying 'sun'. Randy Kryn (talk) 19:06, 5 March 2021 (UTC)


 * I think you are wrong and there are now many mistakes in the article. Please read some of our sources and note how they capitalize.  For example I looked at one:  Next time there is a rainbow look at the sky towards the sun. If rain is falling between you and the sun there will likely be an intense glow. It is best seen when the sun is low and already orange or red.  Gandydancer (talk) 20:17, 5 March 2021 (UTC)
 * Sources usually lower-case sun, moon, and earth. Wikipedia doesn't, and properly treats them as proper nouns. Looking at the sky "towards the sun" literally means looking towards a star which has a proper name, Sun. Randy Kryn (talk) 23:10, 5 March 2021 (UTC)


 * No, our MOS says:
 *  The words sun, earth, moon and solar system are capitalized (as proper names) when used to refer to a specific celestial body in an astronomical context (The Sun is the star at the center of the Solar System; the Moon orbits Earth). They are not capitalized when used outside an astronomical context (It was a clear day and the sun felt warm), or when used in a general sense (Io is a moon of Jupiter). However, they are capitalized in personifications, as in Sol Invictus ('Unconquered Sun') was the ancient Roman sun god.


 * You need to return the correct use of caps in several instances. Gandydancer (talk) 01:03, 6 March 2021 (UTC)
 * Since I am reading the revised text as containing proper names then I can't see your point. For instance, in the example you gave the text refers to the name of the star and not to sunlight. "In the direction of the Sun" seems to be stating exactly the same thing as "In the direction of London" (especially if London is within the line-of-sight) or other proper names. What, in your opinion, am I missing there? Thanks. Randy Kryn (talk) 04:32, 6 March 2021 (UTC)
 * Perhaps it may help to point out that "in the direction of London", or, for example "in the direction of Mars", one uses caps. If I were to say "in the direction Mars and Earth", one would also use caps.  But if I were to say "in the direction of the earth" one would not use caps.  In other words if one must say "the" you don't use caps.  Gandydancer (talk) 09:29, 6 March 2021 (UTC)
 * Depends on where you are. If you are saying that while on Mars (as I am now, don't ask), or even on the International Space Station, Earth would be upper-cased as meaning the planet Earth. "The" isn't relevant to the proper name, as 'the Moon' is a very common word-combination but Wikipedia still correctly upper-cases 'Moon' as a proper name. The upper-casing sometimes looks unusual because sources have lower-cased the names for so long that we are used to seeing them lower-cased. Luckily, the wise ancestral people of Wikipedia decided that that massive nuclear furnace in the sky, or that rock that follows us around and continuously tries to fall onto (and into) our planet, are things real and solid enough to have proper names. Randy Kryn (talk) 12:09, 6 March 2021 (UTC)
 * So you are telling me that you and Wikipedia know more about using caps for heavenly bodies than all of our refs including the Harvard University Department of Physics, for example? Gandydancer (talk) 14:43, 9 March 2021 (UTC)
 * Apparently. Scientific American and other sources actually lower-case Sun and Moon, so many sources are not thinking out the topic and realizing that the massive star, a nuclear furnace, which gives all on Earth life, and the large rock object in the night sky which has been a fascinating and studied object throughout human history, are real enough to have proper names. Those names, given long ago, are Sun and Moon. That Wikipedia goes off-source on this topic as a common sense WP:IAR topic is one of the things I'm most proud of about the site. (and apparently didn't sign, this was written 14:55 by )

Koch, did he make a mistake?
File:Joseph Anton Koch 006.jpg The 1803 painting of Noah by Joseph Anton Koch might deserve a bit more attention (and description). Specifically I wonder if he positions the rainbow correctly, as the sun comes from the right, the rainbow however is nearly flat in front. – Fritz Jörn (talk) 12:32, 18 March 2021 (UTC)
 * Do you have a source that discusses this? -- Escape Orbit (Talk) 12:45, 18 March 2021 (UTC)

Sumerian Flood Older Myth
The article is incorrect. The Sumerian Flood Myth is much older, and a different god placed his bow in the sky to say he would never flood the earth again. Please correct. 75.107.109.44 (talk) 12:04, 19 June 2022 (UTC)

Semi-protected edit request on 7 October 2021
Change 'reflection' in first sentence to 'internal reflection'. 2402:3A80:1E6A:FE62:0:0:0:2 (talk) 12:31, 7 October 2021 (UTC)
 * Red information icon with gradient background.svg Not done: I'm fairly certain that reflection applies and not internal reflection, and I don't have much to review or ponder on given the request has no further explanation. Any sufficiently informed editors are free to perform this edit if I am wrong, however. — Sirdog (talk) 22:43, 8 October 2021 (UTC)
 * It is internal reflection as suggested by the phrase "in water droplets". Not sure if it needs to be made explicit. &minus;Woodstone (talk) 17:22, 9 October 2021 (UTC)
 * Reflection (in the classical model) happens when a ray of light encounters the boundary between two media, and is described entirely by what happens at that single point. Whether the first medium can be considered to be the "inside" or the "outside" of an object is irrelevant to how that reflection happens.
 * There is a phenomenon known as "total internal reflection," or TIR, that occurs in special circumstances. I have no idea why the word "internal" is in the name, as it seems to add no meaning; it does not have to be "inside" an object, and "reflection" already implies "stays in the first medium."
 * But because rainbows are caused by reflections inside the drops, TIR is often incorrectly associated with rainbows. The fact is that the special circumstances that cause TIR cannot occur inside spherical raindrops, and emphasizing the word "internal" only perpetuates that misinformation. JeffJor (talk) 12:23, 17 March 2023 (UTC)

Newton's indigo was what everyone nowadays knows as #0000FF blue
I believe that in the 'modern colours', where there are seven colours, the 'blue' colour, the sixth colour from the left, should be close to #0000FF. I think we should change it to be closer to #0000FF. Restfultree2022 (talk) 09:06, 11 April 2023 (UTC)

Featured picture scheduled for POTD
Hello! This is to let editors know that File:WhereRainbowRises.jpg, a featured picture used in this article, has been selected as the English Wikipedia's picture of the day (POTD) for June 1, 2023. A preview of the POTD is displayed below and can be edited at Template:POTD/2023-06-01. For the greater benefit of readers, any potential improvements or maintenance that could benefit the quality of this article should be done before its scheduled appearance on the Main Page. If you have any concerns, please place a message at Wikipedia talk:Picture of the day. Thank you! &mdash; Amakuru (talk) 15:17, 20 May 2023 (UTC)

Language
Why use Victorian and not Modern English in this article when Wikipedia is for an International audience? — Preceding unsigned comment added by 2003:D5:D740:4D00:70D8:1500:3A63:7CD8 (talk) 14:49, 15 October 2023 (UTC)