The bridge in the sky
Long ago, people thought that rainbows were magic. Some people believed
that a rainbow was a bridge that appeared in the sky when the gods
wanted to leave heaven and come down to earth. People also believed that
if you could find the end of a rainbow—where it touched the
earth—you would find a pot of gold.
Today, we know that a rainbow is simply caused by sunlight shining
through raindrops. To see a rainbow,
you must have the sun behind you and the rain falling- in front of you.
Sunlight looks white, but it is really made up of many colors. When
sunlight enters a raindrop, it breaks up into violet, blue, green,
yellow, orange, and red. We see these colors in the rainbow. But because
the colors blend, we usually see only four or five of them.
Many rays of sunlight, breaking up into their colors and reflecting off
many drops of falling rain, make a shimmering, curved, colorful rainbow.
If the rain is heavy, both ends of the rainbow may appear to touch the
earth, many miles (kilometers) apart.
It’s a Fact
Turn on a hose. Adjust the nozzle to a fine spray. Stand with your
back to the sun. You’ll see a rainbow shining in the spray.
