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A rainbow is a phenomenon which produces what is called a virtual image. For virtual images, your eye sees 'rays' of light which appear to come from an object but they actually originate in a different place.Sounds daft? Well, the image that you see in a mirror is formed on the surface of the mirror but appears to be somewhere behind the mirror - inside the wall - that's virtual, too.There are some good pictures in Wikipedia and a diagram showing how the light bounces around inside each water droplet and then emerges, having been split into its spectral components (dispersed). You see the blue light from a set of drops which are low in the sky and red light from drops that are higher up etc..You may feel that you are near or far from the actual 'bow' but you can't actually get to it because it always forms the arc of a circle about 84 degrees wide - you are in the centre of this circle. You can never actually get to 'the end of the rainbow' - as you chase it, it will appear to move away. So no gold, I'm afraid.BUT - if you have a garden hose on a sunny day, you can make your own , localised, rainbow. It may take some experimenting but, with your back to the sun and with the spray in the right direction, you can see colours.I think what Karen W saw was an 'ordinary' rainbow, due to raindrops at a distance, plus the effect of some nearby spray from the road - this would give the impression that part of the bow was near. You can get some really lovely rainbow effects at times and, because they tend to be very short lived, they are even more impressive.I bought a 'Rainbow Maker' a while ago, which is a faceted glass 'jewel ', rotated by a small solar-powered motor. You stick it onto a sunny window and it gives moving splashes of spectral colours all over the room. Very pretty.
This was not looking through the mirror!
QuoteThis was not looking through the mirror! I didn't say that you had to look through a mirror to see a rainbow- I just said that a rainbow is a virtual image - just ;like any images you see in a mirror. It's not where you think you see it is! It's nowhere, actually.Yes you can see an 'end' to a rainbow, often- I didn't say that either. The end will be where it meets the ground. It is a very weak colour (despite the fact that it can be breathtaking to watch ) so it doesn't show against the ground. Of course, there will be no rainbow where there is no rain (water drops) but you can see a hint of a rainbow against distant hills if rain is falling between you and the hills. You can see the end fine but you can't stand at the end- as the mad man says.And be careful, studying a rainbow whilst you're driving - you may see stars too, if you drive off the road!
AlfHave you seen and understood how the rainbow is formed? There are dozens of links plus many old School textbooks with diagrams.You haven't made it clear whether you were in a car?
A normal rainbow follows the 'laws' strictly. I am looking for some additional factor which would modify the appearance to allow it not to appear circular as with a normal bow.Crystal pendants operate in a totally different way, producing a real image on a surface. If you understand the difference between real and virtual images how can bring that phenomenon into the discussion? If you don't understand, then read about them - it shouldn't compromise any of your principles to find out something like that - and you may see what I am getting at.Let's try some proper Science, for a change.
I'm thinking it has something to do with the light passing through droplets to create two rainbows. Maybe having the light go through the droplets from two sources such as a reflection from one other source has something to do with it? Has the light passing through the droplets been split into two sources?
Karen W. I too experience driving through a rainbow. I was a passenger in a car, driven by by mom. It happened happened about 30 years ago when I was a teenager, but I remember it well, not something easily forgotten and somehow it changes your life forever. It was a double rainbow and it covered our two-lane road like a canopy or covered bridge and went on for several blocks. it was simply, indescribably amazing and we were both in profound and utter awe. I remember wondering while it was happening if other people were seeing it too, or if it was just us. Years later, my mother described it as like "traveling through another dimension." And I couldn't have put it better. That is exactly what it felt like. B.
I have also experienced driving through a rainbow. I was with my husband about 20 yrs ago driving in the Redwoods in California, U.S.. The road was very curvy and the canopy above from the trees was almost complete. Once in a while a break in the forest would allow some sun shine through here and there and the rain was mostly a drizzle. Rounding a sharp hairpin turn while climbing up the mountain road the sun on the dusty windshield made it nearly impossible to see the road for a second, but as we began turn we were suddenly bathed in a spectrum of light. We were driving very slowly on this slippery mountain road. I turned to my husband,to see if he saw the same thing,my husband was focused on the road but I saw him smiling. Then we were through it. It was probably only a few seconds of time but it seemed in slowed motion. It was very cool and I will never forget the feeling of amazement and warmth that we shared that day. When we got to the campground, next to the Pacific Ocean our friends began to tell us about this, "very brillantly colored rainbow that went right down into the trees." They could see it from the beach.To those who do not believe-Scientifically the spectrum can be seen when light shines through a transparent medium (like a raindrop) and undergoes partial internal reflection, and this is refracted between the angles of 40į(violet) and 42į(red). The rest of the colors fall in between. Physics tells us we can never find the end of the rainbow because if we see the rainbow we are already at the proper angle and if we move the angle will change. BUT...physics does not say that a rainbow cannot find us. (Not us personally of course). There is really no reason why, albeit the odds have got to be phenomenal, that if all the conditions were right it is possible. There are rainbows present that we don't see because our angle is wrong between the drops and the sun, so depending on where the sun is in the sky a rainbow could be anywhere.I also want to say that I am thrilled to find this site and others who have experienced this, I knew what we saw that day was real, I just never met anyone else who experienced it too.