What Exactly Is a Rainbow?

Photo: Randy Son Of Robert/Flickr.

I have to admit: I learned about rainbows in my ninth-grade science class, but God help me if I can recall what we actually learned. I do remember our teacher playing us Kermit the Frog’s “Rainbow Connection” before we started the lesson though. The rest is a blur.

Turns out that rainbows, though simply beautiful to look at, are anything but simple (at least for this English major). See, rainbows are what happen when the sun’s light is refracted through raindrops in the Earth’s atmosphere. The sun’s light looks white to us, but when it passes through raindrops, the raindrop bends the different colors in the light so that they spread out. These colors are reflected back to us as a rainbow.

That’s the simple explanation (or the only one I dare to attempt).

Three things have to happen in order for a rainbow to appear: First, it has to be raining. Second, it also has to be sunny. And third, you have to be between the sun and the rain to see the rainbow. Rainbows often appear after a brief thunderstorm when the sun is low in the sky.

Have you ever tried to chase a rainbow as a kid? Or heard about the proverbial pot of gold at the end of a rainbow? Well, since a rainbow is really just an optical illusion, you can never find the end of it — as you move, so does the rainbow.

Another interesting tidbit about rainbows? They are actually full circles and not semicircles. We just can’t see the full circle because we can see only as far the horizon from our vantage point on the ground. Airplane pilots have reported seeing full-circle rainbows, since from their viewpoint in an airplane’s cockpit, they get a pretty expansive view of both the sky and the ground.

So why don’t you see them anymore? Rainbows seem uncommon these days, but probably because we’re moving too fast to notice them. That has a lot to do with how we spend our time now that we’re adults (we’re not exactly spending hours outside playing in the yard). We’re also probably too busy wrapped up in technology to stop and notice them. We’re probably at the movies, checking our email or posting on Facebook when a rainbow is appearing right outside our window.

Rainbows have long been a weighty symbol, whether it be symbolizing the new era of hope after the flood in the Bible or symbolizing gay pride today. But for our purposes, let’s just say that a rainbow is just that, a bow created from rain, a way for us to remember to pause from the din of our busy lives and enjoy the beauty of the world around us.

— Chanie

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