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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!