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Archive 1 | Archive 2 | Archive 3 |
Is the arc of a rainbow the portion of a "bubble" that we can see? The bubble would occur because a pocket of air having a lower (or higher) temperature and relative humidity is in contact with the predominant air mass with a different temperature and relative humidity. Has anyone ever explained the arc? — Preceding unsigned comment added by 76.118.153.139 ( talk) 15:44, 16 July 2012 (UTC)
I am thinking again about splitting this heterogeneous article into two separate articles, Rainbow (physics) and Rainbow (culture), as discussed on the Talk-page before ( here). It is easy, almost no editing would be required because Culture is already a single section. We could rename the current article to Rainbow (physics) (keeping its history), move the entire culture section into the new article Rainbow (culture), and create a redirect page for redirecting Rainbow to Rainbow (physics). The above LGBT rainbow flag discussion would then be at home in culture. Ceinturion ( talk) 10:23, 2 August 2012 (UTC)
The rainbow is not a physical object and cannot be reflected as in a mirror. The reflected rainbow is a different rainbow, not an image of the one in the sky. ( 78.150.192.55 ( talk) 19:20, 23 July 2012 (UTC))
It is precisely because the reflected rainbow may look like a mirror image of the rainbow in the sky, that the sentence is misleading. The reflected rainbow is an image of the rainbow that would be seen by an observer located where the light rays are reflected from the water surface. A diagram would help. Other websites give satisfactory explanations. ( 78.151.36.249 ( talk) 12:52, 25 July 2012 (UTC))
I agree with the revised wording, but I still think a diagram would help and remove the need for the complicated argument that has developed. The reflected rainbow is indeed a mirror image, but not a mirror image of the one that may or may not be visible in the sky.( 2.96.70.225 ( talk) 16:01, 9 August 2012 (UTC))
"When a rainbow appears above a body of water ..." implies that a reflected rainbow can be seen only when the observer can see a primary rainbow in the sky.( 89.240.176.211 ( talk) 20:43, 18 August 2012 (UTC))
It's actually a flattened drop of water due to the upward resistance. I would present it as more of a pancake shape with an elliptic cross section. This shape more clearly demonstraits the white wash observed above and below the horizontal position of the backlight. — Preceding unsigned comment added by 70.185.221.179 ( talk) 00:52, 15 August 2012 (UTC)
Would it be possible for someone from Wikipedia to create a/some page(s) about the sources from Optics InfoBase (e.g. 14, 15) as it cost $15 or $35 depending on whether you are a member or not.
Many Thanks
Thomas Rules 19:57, 13 November 2012 (UTC)
In all the photos, when the sun is behind the photographer the inside of the primary rainbow is blue and the outside is red. In the little refraction diagram, which appears to show a drop on the upper part of a rainbow, the colors are reversed. You should fix this so it reflects (no pun intended) the reality of the photographs. — Preceding unsigned comment added by 2001:558:6020:13B:7820:6E5C:D4A1:28DE ( talk) 07:16, 28 November 2012 (UTC)
I get it now! The blue and red come out at different angles, at diverging paths. So it is impossible for a single person to see red and blue from the SAME exact water drop. That was the mistake I had made. Blue comes from one set of drops, and red from another. The blue beams are at a shallower angle (more toward the horizontal plane of the Earth's surface) than red beams, so the blue I see must be below the red I see (when looking at the top of the rainbow). This effect is repeated in a circular pattern and I see a blue ring inside red. Thanks for the clarification! So cool! — Preceding unsigned comment added by 146.142.1.10 ( talk) 19:37, 28 November 2012 (UTC)
Someone spelled maneuver wrong in the overview section. They spelled it manoeuvre. It's a simple fix, but the article is semi-protected (not sure why) so i cant do it myself. -- The Great and Powerful Qbr12 ( talk) 19:46, 24 December 2012 (UTC)
Thanks for catching it. Happy Holidays.... Pocketthis ( talk) 00:23, 25 December 2012 (UTC)
noun \mə-ˈnü-vər, -ˈnyü-\ 1 a : a military or naval movement b : an armed forces training exercise; especially : an extended and large-scale training exercise involving military and naval units separately or in combination —often used in plural".
How reliable is the photo and description of the rare monochrome rainbow, which was added to the article by Astronautilus on 16 februari 2011? My impression is that it is an artificial image, taken through a red filter. A quick search on internet did not provide similar images. In addition, a quick search on internet did not provide a reference for the existence of this category of rainbow. Is it original research? Ceinturion ( talk) 11:06, 29 November 2012 (UTC)
He is a professional photographer. I guess you could ask him. If you look at this one from the Commons and imagine it cropped down to just the lower right or left it can somewhat match the one we are using. Gandydancer ( talk) 04:16, 30 November 2012 (UTC)
Why does the article on the colours in the rainbow describe the seven traditional colours as "primary colours"? This term usually refers to the three colours used in mixing light or pigments, with colours such as orange being termed secondary colours. — 146.179.8.133 ( talk) 11:33, 12 February 2013 (UTC)
A "snowbow" is a phenomenon of the same nature as rainbow, but with a few differences: they have a steeper slope and appear to encircle the sun ( a photo) — Preceding unsigned comment added by 85.181.224.88 ( talk) 19:46, 15 March 2013 (UTC)
This article is missing the cultural significance of rainbows, their symoblism, use in legends and myths, etc. There should be a summary of those articles in that section, not just a bare sentence. -- 65.92.180.137 ( talk) 23:04, 28 March 2013 (UTC)
Just when we think Wikipedia is finished another glaring hole pops up! While doing the above research I realized that we have not covered the reason that the sky inside of a rainbow is always brighter than the sky outside of it. Here is a good source to explain it: [10]. Anyone care to tackle it? If not I will when I have time--I'm working on something else right now. Gandydancer ( talk) 13:25, 18 April 2013 (UTC) I put it in the article and hope it is OK. Gandydancer ( talk) 15:38, 19 April 2013 (UTC)
I can't see where this would fit in the main article, but a rainbow appears (obviously, when you think about it) as a complete circle when viewed from an aircraft. I have seen this once, and it's spectacular! FCR 86.220.74.222 ( talk) 10:36, 18 April 2013 (UTC)
According to [11] prior to this search, there were only 5 scientific descriptions of tertiary rainbows in nature, over a period of 250 years. Now, there's photographic proof of tertiary and quaternary ones. It would be good to add photos of these if possible, and expand the section on higher order rainbows. (along with the science for them) -- 65.94.79.6 ( talk) 09:01, 26 June 2013 (UTC)
I have reverted a string of edits to this section. It is not correct to say that one can't see the full circle because there isn't one. While all rainbows are, in a sense, an illusion, they are full circles but the horizon blanks out the lower portion. Please discuss before again adding this information. Gandydancer ( talk) 21:56, 3 October 2013 (UTC)
I have reverted the following edit because Wikipedia is supposed to be written for readers with a general education and not only those with degrees in math. Most sites that discuss full-circle rainbows are easy to understand for the general reader and if they want to learn more the site used for (some) of this information may be useful. Here is the section that I am reverting to a more understandable version:
A rainbow looks like a circle of angular radius 42° centered on the antisolar point (the point marked by the shadow of the viewer's head), but actually it is formed by light reflected in water droplets located in a cone of angle 42° around the shadow line from the observer's eye. When the Sun is at elevation α, the bottom of the cone is at −α−42°. When the Sun is at 48°, the bottom of the cone is just at your feet (−90%deg;). When the Sun is higher than 48° the bottom of the cone is towards the Sun, and reflected light from the bottom will not reach the observer, and no full circle can be seen. When the Sun is lower than 48°, a full circle could be seen if droplets are present close by. The intensity of the colour is the cumulative effect of all droplets in the cone. The higher part of the cone will stretch far away and contain many droplets, especially if it is above the horizon. The lower part of the cone intersects the Earth's surface closer by, and fewer drops contribute, resulting in a faint colour. To see a full circle rainbow with intense colours, one must be able to look down on it, such as from an aircraft. Part of this edit is sourced, but even still, should Wikipedia expect the general reader to understand what, for instance, "−α−42°" might mean? Gandydancer ( talk) 22:18, 5 October 2013 (UTC)
I've had another go at fixing this. As previously noted, previously the section started with a confusing and unclear discussion of what was already explained in the article. And then when it finally got around to explaining "full circles" it wasn't much clearer. It also had a few grammatical errors. I've tried to re-word; probably not perfect, but I hope a improvement. -- Escape Orbit (Talk) 18:34, 6 October 2013 (UTC)
Last week someone changed the word 'fogbow' in 'fogbow spectre', in the legends of this image. (diff) Isn't that a mistake? I thought the Brocken spectre is someone's shadow at the center of a fogbow, and I would not mix those words. Could a native speaker of English have a look at it? Ceinturion ( talk) 16:04, 9 October 2013 (UTC)
The direction of the sunlight is changed by the angle
twice, then the light is refracted entering or leaving a water droplet.
The direction is changed by
when the light is reflected once inside the droplet.
Total deflection after two
refractions and k
reflections in a water
droplet therefore is
The condition
means that the direction does not change varying the angle of incidence. This condition corresponds to maximum intensity.
From this condition we derive
That can be transformed to
and finally
In case of one reflection (k=1) in a water droplet that has a refractive index of about 1.33 the angle is about 180 - 42 degrees.
In case of two reflections the total angle change is 180° + 50,1°, in case of three reflections 360° - 42.8° and 360° + 42,3° in case of four reflections inside the droplet. 178.201.250.13 ( talk) 23:01, 7 November 2013 (UTC)
This
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Our God mentions in the Holy Bible in the first chapter - Genesis Chapter 9 verses 11-17..... The first Rainbow (bow).
The Rainbow symbolizes God's promise to never flood the earth again.
Genesis 9:11-17
11 And I will establish my covenant with you; neither shall all flesh be cut off any more by the waters of a flood; neither shall there any more be a flood to destroy the earth.
12 And God said, This is the token of the covenant which I make between me and you and every living creature that is with you, for perpetual generations:
13 I do set my bow in the cloud, and it shall be for a token of a covenant between me and the earth.
14 And it shall come to pass, when I bring a cloud over the earth, that the bow shall be seen in the cloud:
15 And I will remember my covenant, which is between me and you and every living creature of all flesh; and the waters shall no more become a flood to destroy all flesh.
16 And the bow shall be in the cloud; and I will look upon it, that I may remember the everlasting covenant between God and every living creature of all flesh that is upon the earth.
17 And God said unto Noah, This is the token of the covenant, which I have established between me and all flesh that is upon the earth.
Tothster (
talk) 07:30, 24 November 2013 (UTC)
I have the idea that a rainbow is a hologram, that each droplet of water is a tiny rainbow and that together they reflect holographically the rainbow we see in the sky. I researched around and haven't found any mention of it. Any comments? Mappley ( talk) 02:33, 23 November 2013 (UTC)
Very high standards, but I couldn't help noticing a typo in the second paragraph - incorrect possessive:
"'the illuminated droplets above the horizon from the observers line of sight'" ("observers" is plural of "observer")
should be:
"'the illuminated droplets above the horizon from the observer's line of sight'" ("observer's" is intended meaning)
Phylasnier (
talk) 12:53, 22 December 2013 (UTC)
Let's restart. Most of the relevant information is already present elsewhere in the article. Look at the copied pictures. The first shows that at a certain angle there is maximum reflection. The second shows that this angle depends slightly on the colour. So for ease of talking lets say, the maximum reflection for red is at 42° and the maximum for violet at 41°. The different colours from one drop reflect in different directions and do not reach the same observer. One observer sees red from drops in direction at 42° from the shadow of their head, and violet from other drops at 41° from the shadow. When the line of sight is above the horizon, one can see far and catch reflections from many drops, leading to clearly visible colours. More to the side and bottom of the rainbow, the line of sight touches the surface, and only drops up to that point contribute. In most cases, the lowest line of sight (to the bottom of the rainbow) will touch the ground at a few meters distance, so only very few drops contribute. If one is in the rain and looking carefully at a rainbow, one will almost always be able to see parts under the horizon. In bright Sun and fine dense rain, one will see the rainbow continue faintly till rather close by. The Earth is not in the way, but prevents raindrops to be present below the surface. − Woodstone ( talk) 12:41, 9 October 2013 (UTC)
In 1637 Rene Descartes wrote, according to this:
From "Physics of the air" by William Jackson Humphreys:
− Woodstone ( talk) 14:42, 9 October 2013 (UTC)
Both sources are not WP and show that (part of) a rainbow can be seen nearby. That implies immediately that a full circle can be seen. − Woodstone ( talk) 09:15, 10 October 2013 (UTC)
The rainbow in this example has nothing to do with any horizons. So from my vantage point I only see the half circle, and for me "there is no rainbow below anything". The bottom half does not exist from my perspective. However, again, if someone were in a plane looking down at the same rainbow, he would see the full circle if the droplets were high enough. For him, the rainbow would begin at a higher altitude, and he would be able to see a full circle. I've been doing nothing but reading everything I can get my hands on about rainbows, and I'm pretty sure I finally understand the phenomenon, not so much technically, but certainly logically. However, my intention here was not to be a science editor, and suggest the correct way to explain it, but to suggest "Opening the Article with the fact that all rainbows are Full Circle Rainbows", and at least eliminate the need to have a "section" explaining it further down in the article. I'll be happy to let the science editors wrestle with each other's egos, until a compromise explanation is agreed upon. I'll even be happy to help simplify it, if asked to, when they finally agree on something here. Pocketthis ( talk) 21:49, 13 October 2013 (UTC)
I'm sorry I'm a bit late into this discussion, but I have to say that you came to the wrong conclusion. From an airplane a rainbow can be a full circle as is described in the Variants section, but normally the rainbow is just a part of a circle. Saying "all rainbows are circles" is like saying "the moon is always full". It would be true if you where allowed to change your perspective (go high into the sky or out into space, respectively), but allowing that would make the original statement meaningless since it would also change the phenomena you are talking about. A rainbow is an optical phenomena, so it is what you see. If it that looks like half a circle it is half a circle. I suggest we remove the second paragraph of the lead starting with "All rainbows are full circles" since you need a quite odd definition of the rainbow to make it true and the only reference is a blog post. Ulflund ( talk) 15:35, 2 January 2014 (UTC)
http://wwwp.cord.edu/faculty/manning/physics215/studentpages/genamahlen.html http://science.howstuffworks.com/nature/climate-weather/storms/rainbow2.htm
Pocketthis, the reason you think all sources say that "all rainbows are full circles" is because you interpret quotes like "If you were up above the rain, you would see the rainbow as a full circle" as "all rainbows are full circles". I know this because that is the only thing http://science.howstuffworks.com/nature/climate-weather/storms/rainbow2.htm says about full circles.
Googling for "are all rainbows full circles" will give you biased results since it will only show you pages that talk about rainbows as full circles, which most pages about rainbows do not. I still went through the list to prove my point and here are the top 10 hits:
Googling instead for "Full circle rainbow" gives mostly hits that talk about the special case of rainbows where they form a cull circle. I agree that describing rainbows as full circles is common but it is even more common to describe them as bows or arcs. It still doesn't make the statement "all rainbows are full circles" true. Is Wikipedia supposed to help spread misconceptions just because they are already widely spread? Ulflund ( talk) 16:22, 4 January 2014 (UTC)
Newton discovered that white light can be split into rainbows, but ranbows can also be described as 3 sinus functions phase shifted from each other by 2/3 π.
If the sinus functions above are used as the combined color intensity of red, green, and blue we get the rainbow below.
Is it possible for this mathematical description of rainbows to be included in article?
Zanthius (
talk) 22:11, 18 January 2014 (UTC)
This
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In the section titled "overview" on the second line, reference is made to the "sun ray's". This is grammatically incorrect. Could I request that it be changed to the "sun's rays" 195.89.50.9 ( talk) 13:22, 30 March 2014 (UTC)
Prior content in this article duplicated one or more previously published sources. The material was copied from: here. Copied or closely paraphrased material has been rewritten or removed and must not be restored, unless it is duly released under a compatible license. (For more information, please see "using copyrighted works from others" if you are not the copyright holder of this material, or "donating copyrighted materials" if you are.) For legal reasons, we cannot accept copyrighted text or images borrowed from other web sites or published material; such additions will be deleted. Contributors may use copyrighted publications as a source of information, but not as a source of sentences or phrases. Accordingly, the material may be rewritten, but only if it does not infringe on the copyright of the original or plagiarize from that source. Please see our guideline on non-free text for how to properly implement limited quotations of copyrighted text. Wikipedia takes copyright violations very seriously, and persistent violators will be blocked from editing. While we appreciate contributions, we must require all contributors to understand and comply with these policies. Thank you. Diannaa ( talk) 00:23, 29 April 2014 (UTC)
External link to Footnote 9 is outdated. At present, it reads - Hutchison, Niels (2004). "Music For Measure: On the 300th Anniversary of Newton's Opticks". Colour Music. Retrieved 2006-08-11. & links to - http://home.vicnet.net.au/~colmusic/opticks3.htm The page has been relocated to - http://www.colourmusic.info/opticks3.htm Also, the link could well go to the start of the section about "Opticks", on the relation of spectral colours & musical notes - http://www.colourmusic.info/opticks1.htm
Another possible link from the "Colour Music" site would be - Hutchison, Niels. "Stairways to Heaven: Rainbow Enlightenment". Colour Music. http://www.colourmusic.info/rain.htm This is the first of 2 pages on the use/development of rainbows in art. It could well be used for the final paragraph, entitled "Culture". which begins - "Rainbows form a significant part of human culture. They occur frequently in mythology, and have been used in the arts."
Nielshutch ( talk) 10:09, 1 May 2014 (UTC) Nielshutch ( talk) 13:38, 10 May 2014 (UTC)
"The light at the back of the raindrop does not undergo total internal reflection, and some light does emerge from the back. However, light coming out the back of the raindrop does not create a rainbow between the observer and the sun because spectra emitted from the back of the raindrop do not have a maximum of intensity, as the other visible rainbows do, and thus the colours blend together rather than forming a rainbow"
Am I right in thinking that this needs to be edited?
...light coming out of the back of the rainbow...
...travels between the raindrop and infinity and so can never create a rainbow between the observer and the sun, not even the rainbow can do this because it is created between the observer and infinity ie the sun is behind the observer.
I think what the original text is getting at is that light travelling out of the back of the raindrop is diffuse and cannot create further rainbows beyond the point of maximum intensity which I think must be at 42° between the sun and the observer as it is reflected at the appropriate distance from the observer depending on the hight of the sun.
So maybe it should read "light coming out the back of the raindrop does not create a rainbow in relation to the observer and the sun..."
but then I'm not a scientist I'm a wiki reader so your thoughts please, -- Indipage ( talk) 20:03, 27 June 2014 (UTC)
204.214.145.6 ( talk) 22:42, 1 October 2014 (UTC) The word "Dispersion" should be included in the first line of the Article, along with Reflection and Refraction. First, there is the Refraction that occurs when light enters the drop. Next is the Dispersion of different wavelenghts (colours), as they get refracted at different angles. Then comes the Total Internal Reflection, and finally the refraction that occurs when light comes out of the drop. Hence, I would prefer to put Refraction, Dispersion and Reflection in that order. Raghavendra P Umarji 204.214.145.6 ( talk) 22:42, 1 October 2014 (UTC)
i just stumbled across a video from MinutePhysics all about misconceptions over the colours in a rainbow. ≈ Sensorsweep ( talk) 02:05, 29 October 2014 (UTC)
The picture "White light separates into different colours" puzzles me. The red light is depicted there "on the bottom". If the picture were correct, the red color would lie in the inner part of a primary rainbow, but it lies in the outer part. Is the picture wrong? In any case this needs a clarification... — Preceding unsigned comment added by 70.114.197.37 ( talk) 01:17, 3 November 2014 (UTC)
The todo-list at the holy top of this Talk page was added in 2007, and it has been ignored ever since. It is possible to add the formula for the angle, 4 arcsin(q/n) - 2 arcsin(q), where q = √((4-n²)/3), but formulas scare away readers. Or is it time to remove this item from the todo-list (or the entire todo-list)? Ceinturion ( talk) 22:00, 2 September 2014 (UTC)
The explanation is actually not difficult. For a quantitative calculation we need the entire angle change as a function of incidence angle. Is the total angular change not dependent on the angle of incidence many rays are going in the same direction, that means the intensity is highest at that angle of incidence. 84.118.81.7 ( talk) 18:25, 16 November 2014 (UTC)
This is an archive of past discussions. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page. |
Archive 1 | Archive 2 | Archive 3 |
Is the arc of a rainbow the portion of a "bubble" that we can see? The bubble would occur because a pocket of air having a lower (or higher) temperature and relative humidity is in contact with the predominant air mass with a different temperature and relative humidity. Has anyone ever explained the arc? — Preceding unsigned comment added by 76.118.153.139 ( talk) 15:44, 16 July 2012 (UTC)
I am thinking again about splitting this heterogeneous article into two separate articles, Rainbow (physics) and Rainbow (culture), as discussed on the Talk-page before ( here). It is easy, almost no editing would be required because Culture is already a single section. We could rename the current article to Rainbow (physics) (keeping its history), move the entire culture section into the new article Rainbow (culture), and create a redirect page for redirecting Rainbow to Rainbow (physics). The above LGBT rainbow flag discussion would then be at home in culture. Ceinturion ( talk) 10:23, 2 August 2012 (UTC)
The rainbow is not a physical object and cannot be reflected as in a mirror. The reflected rainbow is a different rainbow, not an image of the one in the sky. ( 78.150.192.55 ( talk) 19:20, 23 July 2012 (UTC))
It is precisely because the reflected rainbow may look like a mirror image of the rainbow in the sky, that the sentence is misleading. The reflected rainbow is an image of the rainbow that would be seen by an observer located where the light rays are reflected from the water surface. A diagram would help. Other websites give satisfactory explanations. ( 78.151.36.249 ( talk) 12:52, 25 July 2012 (UTC))
I agree with the revised wording, but I still think a diagram would help and remove the need for the complicated argument that has developed. The reflected rainbow is indeed a mirror image, but not a mirror image of the one that may or may not be visible in the sky.( 2.96.70.225 ( talk) 16:01, 9 August 2012 (UTC))
"When a rainbow appears above a body of water ..." implies that a reflected rainbow can be seen only when the observer can see a primary rainbow in the sky.( 89.240.176.211 ( talk) 20:43, 18 August 2012 (UTC))
It's actually a flattened drop of water due to the upward resistance. I would present it as more of a pancake shape with an elliptic cross section. This shape more clearly demonstraits the white wash observed above and below the horizontal position of the backlight. — Preceding unsigned comment added by 70.185.221.179 ( talk) 00:52, 15 August 2012 (UTC)
Would it be possible for someone from Wikipedia to create a/some page(s) about the sources from Optics InfoBase (e.g. 14, 15) as it cost $15 or $35 depending on whether you are a member or not.
Many Thanks
Thomas Rules 19:57, 13 November 2012 (UTC)
In all the photos, when the sun is behind the photographer the inside of the primary rainbow is blue and the outside is red. In the little refraction diagram, which appears to show a drop on the upper part of a rainbow, the colors are reversed. You should fix this so it reflects (no pun intended) the reality of the photographs. — Preceding unsigned comment added by 2001:558:6020:13B:7820:6E5C:D4A1:28DE ( talk) 07:16, 28 November 2012 (UTC)
I get it now! The blue and red come out at different angles, at diverging paths. So it is impossible for a single person to see red and blue from the SAME exact water drop. That was the mistake I had made. Blue comes from one set of drops, and red from another. The blue beams are at a shallower angle (more toward the horizontal plane of the Earth's surface) than red beams, so the blue I see must be below the red I see (when looking at the top of the rainbow). This effect is repeated in a circular pattern and I see a blue ring inside red. Thanks for the clarification! So cool! — Preceding unsigned comment added by 146.142.1.10 ( talk) 19:37, 28 November 2012 (UTC)
Someone spelled maneuver wrong in the overview section. They spelled it manoeuvre. It's a simple fix, but the article is semi-protected (not sure why) so i cant do it myself. -- The Great and Powerful Qbr12 ( talk) 19:46, 24 December 2012 (UTC)
Thanks for catching it. Happy Holidays.... Pocketthis ( talk) 00:23, 25 December 2012 (UTC)
noun \mə-ˈnü-vər, -ˈnyü-\ 1 a : a military or naval movement b : an armed forces training exercise; especially : an extended and large-scale training exercise involving military and naval units separately or in combination —often used in plural".
How reliable is the photo and description of the rare monochrome rainbow, which was added to the article by Astronautilus on 16 februari 2011? My impression is that it is an artificial image, taken through a red filter. A quick search on internet did not provide similar images. In addition, a quick search on internet did not provide a reference for the existence of this category of rainbow. Is it original research? Ceinturion ( talk) 11:06, 29 November 2012 (UTC)
He is a professional photographer. I guess you could ask him. If you look at this one from the Commons and imagine it cropped down to just the lower right or left it can somewhat match the one we are using. Gandydancer ( talk) 04:16, 30 November 2012 (UTC)
Why does the article on the colours in the rainbow describe the seven traditional colours as "primary colours"? This term usually refers to the three colours used in mixing light or pigments, with colours such as orange being termed secondary colours. — 146.179.8.133 ( talk) 11:33, 12 February 2013 (UTC)
A "snowbow" is a phenomenon of the same nature as rainbow, but with a few differences: they have a steeper slope and appear to encircle the sun ( a photo) — Preceding unsigned comment added by 85.181.224.88 ( talk) 19:46, 15 March 2013 (UTC)
This article is missing the cultural significance of rainbows, their symoblism, use in legends and myths, etc. There should be a summary of those articles in that section, not just a bare sentence. -- 65.92.180.137 ( talk) 23:04, 28 March 2013 (UTC)
Just when we think Wikipedia is finished another glaring hole pops up! While doing the above research I realized that we have not covered the reason that the sky inside of a rainbow is always brighter than the sky outside of it. Here is a good source to explain it: [10]. Anyone care to tackle it? If not I will when I have time--I'm working on something else right now. Gandydancer ( talk) 13:25, 18 April 2013 (UTC) I put it in the article and hope it is OK. Gandydancer ( talk) 15:38, 19 April 2013 (UTC)
I can't see where this would fit in the main article, but a rainbow appears (obviously, when you think about it) as a complete circle when viewed from an aircraft. I have seen this once, and it's spectacular! FCR 86.220.74.222 ( talk) 10:36, 18 April 2013 (UTC)
According to [11] prior to this search, there were only 5 scientific descriptions of tertiary rainbows in nature, over a period of 250 years. Now, there's photographic proof of tertiary and quaternary ones. It would be good to add photos of these if possible, and expand the section on higher order rainbows. (along with the science for them) -- 65.94.79.6 ( talk) 09:01, 26 June 2013 (UTC)
I have reverted a string of edits to this section. It is not correct to say that one can't see the full circle because there isn't one. While all rainbows are, in a sense, an illusion, they are full circles but the horizon blanks out the lower portion. Please discuss before again adding this information. Gandydancer ( talk) 21:56, 3 October 2013 (UTC)
I have reverted the following edit because Wikipedia is supposed to be written for readers with a general education and not only those with degrees in math. Most sites that discuss full-circle rainbows are easy to understand for the general reader and if they want to learn more the site used for (some) of this information may be useful. Here is the section that I am reverting to a more understandable version:
A rainbow looks like a circle of angular radius 42° centered on the antisolar point (the point marked by the shadow of the viewer's head), but actually it is formed by light reflected in water droplets located in a cone of angle 42° around the shadow line from the observer's eye. When the Sun is at elevation α, the bottom of the cone is at −α−42°. When the Sun is at 48°, the bottom of the cone is just at your feet (−90%deg;). When the Sun is higher than 48° the bottom of the cone is towards the Sun, and reflected light from the bottom will not reach the observer, and no full circle can be seen. When the Sun is lower than 48°, a full circle could be seen if droplets are present close by. The intensity of the colour is the cumulative effect of all droplets in the cone. The higher part of the cone will stretch far away and contain many droplets, especially if it is above the horizon. The lower part of the cone intersects the Earth's surface closer by, and fewer drops contribute, resulting in a faint colour. To see a full circle rainbow with intense colours, one must be able to look down on it, such as from an aircraft. Part of this edit is sourced, but even still, should Wikipedia expect the general reader to understand what, for instance, "−α−42°" might mean? Gandydancer ( talk) 22:18, 5 October 2013 (UTC)
I've had another go at fixing this. As previously noted, previously the section started with a confusing and unclear discussion of what was already explained in the article. And then when it finally got around to explaining "full circles" it wasn't much clearer. It also had a few grammatical errors. I've tried to re-word; probably not perfect, but I hope a improvement. -- Escape Orbit (Talk) 18:34, 6 October 2013 (UTC)
Last week someone changed the word 'fogbow' in 'fogbow spectre', in the legends of this image. (diff) Isn't that a mistake? I thought the Brocken spectre is someone's shadow at the center of a fogbow, and I would not mix those words. Could a native speaker of English have a look at it? Ceinturion ( talk) 16:04, 9 October 2013 (UTC)
The direction of the sunlight is changed by the angle
twice, then the light is refracted entering or leaving a water droplet.
The direction is changed by
when the light is reflected once inside the droplet.
Total deflection after two
refractions and k
reflections in a water
droplet therefore is
The condition
means that the direction does not change varying the angle of incidence. This condition corresponds to maximum intensity.
From this condition we derive
That can be transformed to
and finally
In case of one reflection (k=1) in a water droplet that has a refractive index of about 1.33 the angle is about 180 - 42 degrees.
In case of two reflections the total angle change is 180° + 50,1°, in case of three reflections 360° - 42.8° and 360° + 42,3° in case of four reflections inside the droplet. 178.201.250.13 ( talk) 23:01, 7 November 2013 (UTC)
This
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Our God mentions in the Holy Bible in the first chapter - Genesis Chapter 9 verses 11-17..... The first Rainbow (bow).
The Rainbow symbolizes God's promise to never flood the earth again.
Genesis 9:11-17
11 And I will establish my covenant with you; neither shall all flesh be cut off any more by the waters of a flood; neither shall there any more be a flood to destroy the earth.
12 And God said, This is the token of the covenant which I make between me and you and every living creature that is with you, for perpetual generations:
13 I do set my bow in the cloud, and it shall be for a token of a covenant between me and the earth.
14 And it shall come to pass, when I bring a cloud over the earth, that the bow shall be seen in the cloud:
15 And I will remember my covenant, which is between me and you and every living creature of all flesh; and the waters shall no more become a flood to destroy all flesh.
16 And the bow shall be in the cloud; and I will look upon it, that I may remember the everlasting covenant between God and every living creature of all flesh that is upon the earth.
17 And God said unto Noah, This is the token of the covenant, which I have established between me and all flesh that is upon the earth.
Tothster (
talk) 07:30, 24 November 2013 (UTC)
I have the idea that a rainbow is a hologram, that each droplet of water is a tiny rainbow and that together they reflect holographically the rainbow we see in the sky. I researched around and haven't found any mention of it. Any comments? Mappley ( talk) 02:33, 23 November 2013 (UTC)
Very high standards, but I couldn't help noticing a typo in the second paragraph - incorrect possessive:
"'the illuminated droplets above the horizon from the observers line of sight'" ("observers" is plural of "observer")
should be:
"'the illuminated droplets above the horizon from the observer's line of sight'" ("observer's" is intended meaning)
Phylasnier (
talk) 12:53, 22 December 2013 (UTC)
Let's restart. Most of the relevant information is already present elsewhere in the article. Look at the copied pictures. The first shows that at a certain angle there is maximum reflection. The second shows that this angle depends slightly on the colour. So for ease of talking lets say, the maximum reflection for red is at 42° and the maximum for violet at 41°. The different colours from one drop reflect in different directions and do not reach the same observer. One observer sees red from drops in direction at 42° from the shadow of their head, and violet from other drops at 41° from the shadow. When the line of sight is above the horizon, one can see far and catch reflections from many drops, leading to clearly visible colours. More to the side and bottom of the rainbow, the line of sight touches the surface, and only drops up to that point contribute. In most cases, the lowest line of sight (to the bottom of the rainbow) will touch the ground at a few meters distance, so only very few drops contribute. If one is in the rain and looking carefully at a rainbow, one will almost always be able to see parts under the horizon. In bright Sun and fine dense rain, one will see the rainbow continue faintly till rather close by. The Earth is not in the way, but prevents raindrops to be present below the surface. − Woodstone ( talk) 12:41, 9 October 2013 (UTC)
In 1637 Rene Descartes wrote, according to this:
From "Physics of the air" by William Jackson Humphreys:
− Woodstone ( talk) 14:42, 9 October 2013 (UTC)
Both sources are not WP and show that (part of) a rainbow can be seen nearby. That implies immediately that a full circle can be seen. − Woodstone ( talk) 09:15, 10 October 2013 (UTC)
The rainbow in this example has nothing to do with any horizons. So from my vantage point I only see the half circle, and for me "there is no rainbow below anything". The bottom half does not exist from my perspective. However, again, if someone were in a plane looking down at the same rainbow, he would see the full circle if the droplets were high enough. For him, the rainbow would begin at a higher altitude, and he would be able to see a full circle. I've been doing nothing but reading everything I can get my hands on about rainbows, and I'm pretty sure I finally understand the phenomenon, not so much technically, but certainly logically. However, my intention here was not to be a science editor, and suggest the correct way to explain it, but to suggest "Opening the Article with the fact that all rainbows are Full Circle Rainbows", and at least eliminate the need to have a "section" explaining it further down in the article. I'll be happy to let the science editors wrestle with each other's egos, until a compromise explanation is agreed upon. I'll even be happy to help simplify it, if asked to, when they finally agree on something here. Pocketthis ( talk) 21:49, 13 October 2013 (UTC)
I'm sorry I'm a bit late into this discussion, but I have to say that you came to the wrong conclusion. From an airplane a rainbow can be a full circle as is described in the Variants section, but normally the rainbow is just a part of a circle. Saying "all rainbows are circles" is like saying "the moon is always full". It would be true if you where allowed to change your perspective (go high into the sky or out into space, respectively), but allowing that would make the original statement meaningless since it would also change the phenomena you are talking about. A rainbow is an optical phenomena, so it is what you see. If it that looks like half a circle it is half a circle. I suggest we remove the second paragraph of the lead starting with "All rainbows are full circles" since you need a quite odd definition of the rainbow to make it true and the only reference is a blog post. Ulflund ( talk) 15:35, 2 January 2014 (UTC)
http://wwwp.cord.edu/faculty/manning/physics215/studentpages/genamahlen.html http://science.howstuffworks.com/nature/climate-weather/storms/rainbow2.htm
Pocketthis, the reason you think all sources say that "all rainbows are full circles" is because you interpret quotes like "If you were up above the rain, you would see the rainbow as a full circle" as "all rainbows are full circles". I know this because that is the only thing http://science.howstuffworks.com/nature/climate-weather/storms/rainbow2.htm says about full circles.
Googling for "are all rainbows full circles" will give you biased results since it will only show you pages that talk about rainbows as full circles, which most pages about rainbows do not. I still went through the list to prove my point and here are the top 10 hits:
Googling instead for "Full circle rainbow" gives mostly hits that talk about the special case of rainbows where they form a cull circle. I agree that describing rainbows as full circles is common but it is even more common to describe them as bows or arcs. It still doesn't make the statement "all rainbows are full circles" true. Is Wikipedia supposed to help spread misconceptions just because they are already widely spread? Ulflund ( talk) 16:22, 4 January 2014 (UTC)
Newton discovered that white light can be split into rainbows, but ranbows can also be described as 3 sinus functions phase shifted from each other by 2/3 π.
If the sinus functions above are used as the combined color intensity of red, green, and blue we get the rainbow below.
Is it possible for this mathematical description of rainbows to be included in article?
Zanthius (
talk) 22:11, 18 January 2014 (UTC)
This
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In the section titled "overview" on the second line, reference is made to the "sun ray's". This is grammatically incorrect. Could I request that it be changed to the "sun's rays" 195.89.50.9 ( talk) 13:22, 30 March 2014 (UTC)
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External link to Footnote 9 is outdated. At present, it reads - Hutchison, Niels (2004). "Music For Measure: On the 300th Anniversary of Newton's Opticks". Colour Music. Retrieved 2006-08-11. & links to - http://home.vicnet.net.au/~colmusic/opticks3.htm The page has been relocated to - http://www.colourmusic.info/opticks3.htm Also, the link could well go to the start of the section about "Opticks", on the relation of spectral colours & musical notes - http://www.colourmusic.info/opticks1.htm
Another possible link from the "Colour Music" site would be - Hutchison, Niels. "Stairways to Heaven: Rainbow Enlightenment". Colour Music. http://www.colourmusic.info/rain.htm This is the first of 2 pages on the use/development of rainbows in art. It could well be used for the final paragraph, entitled "Culture". which begins - "Rainbows form a significant part of human culture. They occur frequently in mythology, and have been used in the arts."
Nielshutch ( talk) 10:09, 1 May 2014 (UTC) Nielshutch ( talk) 13:38, 10 May 2014 (UTC)
"The light at the back of the raindrop does not undergo total internal reflection, and some light does emerge from the back. However, light coming out the back of the raindrop does not create a rainbow between the observer and the sun because spectra emitted from the back of the raindrop do not have a maximum of intensity, as the other visible rainbows do, and thus the colours blend together rather than forming a rainbow"
Am I right in thinking that this needs to be edited?
...light coming out of the back of the rainbow...
...travels between the raindrop and infinity and so can never create a rainbow between the observer and the sun, not even the rainbow can do this because it is created between the observer and infinity ie the sun is behind the observer.
I think what the original text is getting at is that light travelling out of the back of the raindrop is diffuse and cannot create further rainbows beyond the point of maximum intensity which I think must be at 42° between the sun and the observer as it is reflected at the appropriate distance from the observer depending on the hight of the sun.
So maybe it should read "light coming out the back of the raindrop does not create a rainbow in relation to the observer and the sun..."
but then I'm not a scientist I'm a wiki reader so your thoughts please, -- Indipage ( talk) 20:03, 27 June 2014 (UTC)
204.214.145.6 ( talk) 22:42, 1 October 2014 (UTC) The word "Dispersion" should be included in the first line of the Article, along with Reflection and Refraction. First, there is the Refraction that occurs when light enters the drop. Next is the Dispersion of different wavelenghts (colours), as they get refracted at different angles. Then comes the Total Internal Reflection, and finally the refraction that occurs when light comes out of the drop. Hence, I would prefer to put Refraction, Dispersion and Reflection in that order. Raghavendra P Umarji 204.214.145.6 ( talk) 22:42, 1 October 2014 (UTC)
i just stumbled across a video from MinutePhysics all about misconceptions over the colours in a rainbow. ≈ Sensorsweep ( talk) 02:05, 29 October 2014 (UTC)
The picture "White light separates into different colours" puzzles me. The red light is depicted there "on the bottom". If the picture were correct, the red color would lie in the inner part of a primary rainbow, but it lies in the outer part. Is the picture wrong? In any case this needs a clarification... — Preceding unsigned comment added by 70.114.197.37 ( talk) 01:17, 3 November 2014 (UTC)
The todo-list at the holy top of this Talk page was added in 2007, and it has been ignored ever since. It is possible to add the formula for the angle, 4 arcsin(q/n) - 2 arcsin(q), where q = √((4-n²)/3), but formulas scare away readers. Or is it time to remove this item from the todo-list (or the entire todo-list)? Ceinturion ( talk) 22:00, 2 September 2014 (UTC)
The explanation is actually not difficult. For a quantitative calculation we need the entire angle change as a function of incidence angle. Is the total angular change not dependent on the angle of incidence many rays are going in the same direction, that means the intensity is highest at that angle of incidence. 84.118.81.7 ( talk) 18:25, 16 November 2014 (UTC)