What makes up rainbows

Why are there so many songs about rainbows?

Published On: Oct 03 2012 10:32:15 AM EDT

While living in paradise, there isn't a doubt that at sometime you will see a rainbow near your home.

Rainbows are a spectacular sight and even Kermit the frog sung about the beautiful displays. You remember this line, "Why are there some many songs about rainbows?"

In the past two weeks, we have seen a number of rainbows across South Florida. Some are small and barely visible in the sky while others are arching from left to right.

Have you ever wondered why rainbows curve the way they do and don't shoot out into space?

The reason rainbows curve has to do with some physics. Ok, I know I said that horrible "P" word, but don't worry, this is simple.

When a ray of light goes into a raindrop, it is refracted, or split up at a different angle, than how it entered the raindrop. The white light of a ray of light is actually comprised of different colors that have different wavelengths. Each of the different colors exits the raindrop at a different angle, but generally between 40 and 42 degrees. That is why we can see the smearing of the colors broken down into Newton's 7 primary colors. You learned them in grade school with ROYGBIV. Red, orange, yellow, green, blue, indigo and violet are the primary colors.

If you have dreams of finding the pot of gold at the end of the rainbow, you need to stop now. Rainbows don't have an end but instead are a full circle. Huh? You might be thinking, "Wait a minute every rainbow that I have seen is just half a circle. You must be wrong."  

We don't actually see the full circle because the earth gets in the way. The closer the sun is to the horizon, the more of the circle we see. Right at sunset, we would see a full semicircle of a rainbow with the top of the arch 42 degrees above the horizon. The higher the sun is in the sky, the less of a rainbow is visible above the horizon. The only way to see the full circle of a rainbow in the sky is to be above the raindrops and have the sun behind you. You would have to look down on the drops from an airplane.

No matter if you see a partial rainbow though, a full semicircle rainbow or one from above I think we know the answer to Kermit's song. There are so many songs about rainbows because they are magical!