Does anyhow have Dekart's graph of the angle in which the rainbow is most visible?
411944
Not his original, but the image in the middle of the first link I'm listing is pretty close to Descartes' from De Meteorologica.  The second source has several modern takes on the image as well as a nice physical explanation of what is going on.
263870
When we draw a circle with a compass, we keep the angle between the two legs constant.\n\nA  ray from the  top most point on the rainbow  to our eye makes an angle to the horizotal direction. Theory says this angle is a constant.\n\nImagine the ray as one leg of long compass and the horizontal direction as another leg which points the center.Keeping the angle constant when the compass is rotated an arc is formed.   \n\n Mathematically we say that the locus of all such points is an arc of a circle.\n\nIf water particle were present on all points on the arc we see a continuous arc of a rain bow.\n\nDuring cloudy  night we can see a full circle of rainbow \naround moon with moon as center.
147785
It is a second rainbow caused by the way light reflects inside of raindrops.  They will appear between 50 and 53 degrees above the horizon and the colors are inverted.  There is also a band of darker sky between the two, this is called an Alexander's band.
57096
Rainbows appear to you to be an arc because from where you are standing, only drops within that arc can reflect (or refract) the colored light to your eyes like a prism.  Someone standing a great distance from you would see their very own arc (and a different pot of gold).  Rainbows are kind of special, just for you.  A cloud of smoke is different because everyone sees the same cloud no matter where they are standing, just different views of it.
122346
Why don't you search the answers to the previously posted questions here on this topic? This has been asked over and over. \n\nHere is a little bit to get you started:\n\nRainbows are caused because the different colors in white light are bent by different amounts in rain drops, so the colors get separated. The sun shines from behind the observer, and then bounces off the back surface of the raindrops, and those raindrops that are at the required position for light to reach the observer from the sun contribute to the rainbow. This arc is formed by the collection of raindrops which are at the vertices of angles of 42 degrees between the observer and the sun.
428614
White light, as you may know, is composed of all the different colors of the rainbow.  When it hits a prism, the light refracts.  Because of the properties of light, however, each specific wavelength refracts differently, so the colors appear to spread out.  Red light refracts the most, then orange light, then yellow light, the green light, then blue light, then violet.  The second refraction (when light exits the prism) simply exaggerates the effects, and what you get is a rainbow.
775696
An inverse rainbow is when the colors are reversed so that the red band of color is on the inside of the rainbow and the blue band is on the outside.  Moonbows, or, halos, are inversed. I wasn't aware that rainbows were different here and there. If they are, my guess is the explanation would be found in optics and, maybe bioelectric fields stuff? Here's a GREAT website for future reference and to put in your Favorites file.  Just click on any "circle" of science and follow the algorithm. Handy little tool. Can't wait to come back and read if someone has an explanation.\nhttp://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html
211510
This site might help "see" what is going on and why.  Interesting question by the way.  I saw my first one last summer and the colors were so bright.  It was amazing!  Had everyone out in the parking lot of the strip mall checking it out.\n\n\nhttp://hyperphysics.phy-astr.gsu.edu/Hbase/atmos/rbowpri.html\n\nhttp://en.wikipedia.org/wiki/Rainbow
1034783
'False' rainbow or secondary one forms because of TOTAL INTERNAL REFLECTION through the optical medium (which probably is the rain drops). Total internal reflection can be understood like this: sine of angle of refraction equals sine of angle of incidence into the refractive index. So, when u kep on increasing the angle of incidence, the angle of refratction also keeps on increasing till when a point comes when it esceeds 90 degrees, i.e., when the refracted ray moves back out of the refracting surface (apparently reflected), and one gets an inverted image, hence the sequence opposite of VIBGYOR. Bye. Hope this helps.
52478
When light is refracted off of droplets of water it enables you to see all the colors that make up white light (sunlight, even light from bulbs.) creating what people more commonly refer to as a rainbow. \n  Go outside on a sunny day and spray the waterhose if you have one. If you look very carefully, you can see that the rainbow you created is not just a semi-circle, but a full circle! The bottom half is harder to see, but it is there. The reason rainbows don't look like that when we see them outside is because we are too low to the ground to see the rest.
328129
just draw a triangle has right angle which dimensions 1,sqrt(3),and hypothenus 2. if you want it, i can send to you
614293
Hertzsprung-Russell  Diagram.  See the wikipedia article for more info.
160214
They also occur as a circle, if you're in a plane (i was in a microlight) above mist/cloud it's the most spectacular sight, I looked down and there was a circular rainbow. It has to do with the fact that you're viewing it from one point, all the rainbow is relative to you.
270700
much to many people's belief's 7 basic colors aren't based on the rainbow colors. in fact some of the colors on the rainbow is actually a mix of primary colors that are really secondary or tetiary. not primary [basic]. so... here we go...\n\n\n7 basic colors are:\n\n1- a cool yellow a.k.a Hansa Yellow Medium—a lemony, slight bias to blue-green;\n\n2- a warm yellow a.k.a New Gamboge— a golden, slight bias to red-orange;\n\n3- a cool blue a.k.a Phthalo Blue (GS)—an icy, slight bias to blue-green;\n\n4- a warm blue a.k.a French Ultramarine— a purplish blue, slight bias to violet;\n\n5-  a cool red a.k.a Quinacridone Rose—a rosy, slight bias to red-violet;\n\n6- a warm red a.k.a Pyrrol Orange—a tomatoey red, slight bias to red-orange;\n\nok..only six [6] are listed here. to get the 7th color,all u need to do is... well here's where the magic is....\n\na] Use a warm and a cool of each primary hue (a warm red and a cool red; a warm yellow and a cool yellow; a warm blue and a cool blue) to mix bright, high-inten sity secondary called a Mixed Primary Hue. The secret is in using the right split primary colors and not crossing over the lines into another section!\n\n++TIPS++\n\nTo mix the oranges, mix the red and yellow within the lines to the left of the circle. First mix orange, and then add more yellow for yellow-or ange and more red for red-orange. \nTo mix the greens, mix the blue and yellow within the lines to the right of the circle. First mix green, and then add more yellow for yellow-green and more blue for blue-green. \nTo mix the purples or violets, mix the pink or rose with the blue within the lines at the bottom of the circle. First mix purple , and then add more blue for blue-violet and red for red-violet. \n\nNow here's the rule that makes this work: 'When mixing two colors on the wheel to achieve high- intensity color, don't cross over the line-stay in each section. Just imagine, no more muddy colors!\n\nCrossing over the lines and mixing the colors on either side of the line causes the mixtures to become less intense and slightly grayer. Cross two lines and even more graying occurs. This graying is called neutralizing. It is the result of a slight touch of that third color being added to the mix. To mix earth colors, you simply cross over the lines or add a warm neutral to your mixtures.\n\nOK ...\n\nNow for the much awaited 7th basic color....\n\nThat's where Quinacridone Burnt Orange—the seventh color of our essential 7 basics-enters the scene… it's a versatile warm neutral.\n\n\nhehe. quite interesting. hmm. [^_^]
380553
When we draw a circle with a compass, we keep the angle between the two legs constant.\n\nA ray from the top most point on the rainbow to our eye makes an angle to the horizontal direction. Theory says this angle is a constant.\n\nImagine the ray as one leg of long compass and the horizontal direction as another leg which points the center. Keeping the angle constant when the compass is rotated an arc is formed. \n\nIf we go high up we can see the whole circle.
1156057
The arc is what YOU see. the truth is that it is a complete circle obscured by the horizon. The colors are not created by the raindrops (moisture droplets would be more accurate) but by the angle the light is shining through them. it is a relative thing as well meaning the view or lack of depends on your perspective. No matter how scientifically I describe this; a rainbow is an amazing thing and I hope you enjoy every one you see!
942352
A rainbow is an optical and meteorological phenomenon that causes a nearly continuous spectrum of light to appear in the sky when the Sun shines onto droplets of moisture in the Earth's atmosphere. It takes the form of a multicoloured arc, with red on the outside and violet on the inside. A double rainbow includes a second, fainter, arc with colors in the opposite order.\n\nEven though a rainbow spans a continuous spectrum of colours, traditionally the full sequence of colours is most commonly cited as red, orange, yellow, green, blue, indigo and violet. It is commonly thought that indigo was included due to the different religious connotations of the numbers six and seven at the time of Isaac Newton's work on light, despite its lack of scientific significance and the poor ability of humans to distinguish colours in the blue portion of the visual spectrum.\n\nScientific explanation\n\nThe rainbow effect can be observed whenever there are water drops in the air and sunlight shining from behind the observer at a low altitude or angle. The most spectacular rainbow displays when half of the sky is still dark with draining clouds and the observer is at a spot with clear sky overhead. The rainbow effect is also commonly seen near waterfalls or fountains. Rainbow fringes can sometimes be seen at the edges of backlit clouds and as vertical bands in distant rain or virga. The effect can also be artificially created by dispersing water droplets into the air during a sunny day.\n\nIn a very few cases, a moonbow, or night-time rainbow, can be seen on strongly moonlit nights. As human visual perception for colour in low light is poor, moonbows are most often perceived to be white.\nRainbows may also appear in the spray of a water fountain\nEnlarge\nRainbows may also appear in the spray of a water fountain\n\nThe rainbow's appearance is caused by dispersion of sunlight as it is refracted by (approximately spherical) raindrops. The light is first refracted as it enters the surface of the raindrop, reflected off the back of the drop, and again refracted as it leaves the drop. The overall effect is that the incoming light is reflected back over a wide range of angles, with the most intense light at an angle of about 40°–42°. This angle is independent of the size of the drop, but does depend on its refractive index. As seawater has a higher refractive index than rain water, the radius of a 'rain'bow in a sea spray is smaller than a true rainbow. This is visible to the naked eye by a misalignment of these bows [1].\n\nSince the water is dispersive, the amount that the sunlight is bent depends upon the wavelength, and hence colour, of the light's constituent parts. Blue light is refracted at a greater angle than red light, but because the area of the back of the droplet has a focal point inside the droplet, the spectrum crosses itself, and therefore the red light appears higher in the sky, and forms the outer colour of the rainbow. Contrary to popular belief, the light at the back of the raindrop does not undergo total internal reflection; however, light that emerges from the back of the raindrop does not create a rainbow between the observer and the Sun. The 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 and do not form a rainbow.\n\nA rainbow does not actually exist at a location in the sky, but rather is an optical phenomenon whose apparent position depends on the observer's location. All raindrops refract and reflect the sunlight in the same way, but only the light from some raindrops reaches the observer's eye. These raindrops are perceived to constitute the rainbow by that observer. The position of a rainbow in the sky is always in the opposite direction of the Sun with respect to the observer, and the interior is always slightly brighter than the exterior. The bow is centred on the shadow of the obser