Kevin Shelton, age 10, of 5kiatook, Oklahoma, for his question:
Is there another side to the rainbow?
Kevin beheld a double rainbow in the sky and he wanted to share the beauteous sight with people far and wide. He wondered whether hopefully it could be seen from the other side, by people farther east. But sad to say, his kindly wish cannot be granted. A rainbow is ruled by complicated angles and corners that decide which way to send its gorgeous colors. Actually, what you see is for your eyes alone because even a person standing beside you gets a slightly different view.
A rainbow is reflected from falling raindrops and it shines only on one side of the cloud. The people below do not even know it is there. Overhead they see only a dark weeping cloud and most likely put up their umbrellas. The people on the other side do not see the shimmering rainbow either. This is because it needs two things to show its colors falling raindrops and lots of sunbeams.
Even then the magic cannot work unless the rain cloud and the sun are neatly placed in certain parts of the sky. This depends on where you happen to be because everybody has a slightly different view of the things up there in the sky. In order to see the rainbow, the sun and the weeping cloud must be on opposite sides of the sky and you are between them. You face the cloud and the cloud faces the sun. The sun's beams travel in straight lines and they must strike the falling raindrops.
The magic happens because the drops of water act like glassy globules and play all sorts of tricks on the sunbeams. A glass prism separates invisible sunbeams into bands of rainbow colors. The same thing happens when sunbeams strike falling raindrops. But you have to be in dust the right place to see the arch of ribbons.
The whole. thing is ruled by those wide and narrow corners called angles. Each shiny round raindrop bends the different wavelengths of light at different angles and separates them to show their secret colors. This is called refraction. Millions of raindrops arrange the separated colors in the same order and reflect them towards your eyes.
Your round eyes arrange the colored angles in a circle, with the short blue wavelengths on the inside and the longest red rays on the outside. You see only the half circle that is in the sky above the ground. And it shows only on your side of the cloud, when the sun is shining from behind you. Miles away, the people on the other side of the cloud do not see the show because from their point of view, the sun and the cloud are in the same part of the sky. The magic is only for those standing between sunshine and showers.
The glimmering colors must shine against a curtain of rainy grey clouds. If the cloud is small, you see only part of the arch. But sometimes a bigger rainbow appears outside the first one. Its colors are reflected twice from the raindrops. It is paler and the red band is inside with the blues on the outside of the curve. Once in a while there are three or even four outer bows. But the folks on the far side of the cloud cannot see them either.