It’s a question that often goes through the minds of children and adults alike when they set eyes on the beauty and wonder of a rainbow . . . but how many of us ever actually go and find out?
Not many would question the delight to be had when seeing a rainbow. The wonderful sight of a rainbow is one of those things that brings a smile to people’s faces and something we never seem to tire of. But despite always wondering, have you ever actually found out how they appear? No? Then let me enlighten you.
Many people know that if you shine a beam of normal white light through a prism, it is split into the many colours, visible and otherwise, that the white light is actually made up of.
Now, raindrops do the same thing to white light that a prism does. If light is shone into them, from the sun, the light that is reflected off the back surface of the drop, just like light bouncing off the surfaces of a prism, is split into the many component colours that make up the white light.
These different component colours, just like from a prism, spread out and leave the raindrop at different angles. The colour of the light that then actually makes it to your eye depends on what angle that raindrop is at, between you and the source of light, the sun.
A raindrop that is higher up in the sky will reflect red light at just the right angle for your eye. A raindrop that is a little lower in the sky will reflect green light at the right angle for your eye. Lower in the sky still and a raindrop will reflect blue light to your eye at just the right angle.
Now, multiply one raindrop by millions, and high in the sky you see a band of red light, lower a band of green, and lower still and band of blue, and the other colours in between accordingly, although these 3 colours are usually the most easily discernible.
And that, is how a rainbow is formed.
Enquiring minds like mine will no doubt want to know how the bow is bow shaped, but you’ll have to wait for my next article to find that out, unless you want to find out elsewhere first of course. Learning is fun, whatever age you are.
