There are Always Two Rainbows

This was the view of a double rainbow from our deck. It stayed for quite a while, so we really got to take it in and appreciate it.

Richard Dawkins, in his seminal book The God Delusion said: “As ever when we unweave a rainbow, it will not become less wonderful.” What he meant was, even if science takes the Bible’s meaning and mystery out of a rainbow, it’s still pretty fucking amazing.

Science tells us a rainbow is the refraction of light into different wavelengths, seven of which our eyes are able to see as the colors red, orange, yellow, green, blue, indigo and violet. Raindrops are the mediums for this wonderful reaction. Raindrops actually change the speed of light, from Einstein’s value of “c” (about 300 million meters per second, which, of course, is really, really fast) into much slower wavelengths. So the white light from the sun is transformed into those gorgeous colors that our evolved eyes are able to see.

What you may not know is that there are always two rainbows. It’s just that the second rainbow is often too faint to see.

And get this: the colors in the second rainbow are inverted from the first rainbow, because the light rays were reflected once more inside the raindrop before exiting. So we see the second rainbow as violet, indigo, blue, green, yellow, orange and red. It’s a wondrous thing, hey?

Which is why Richard Dawkins used the rainbow as one of his many examples where the laws and principles of science were, in his opinion, far more amazing and awe-inspiring than any story conjured up by the world’s religions. For example, Christianity tells us the rainbow was a sign from God that he would never again flood the world.

“Whenever I bring clouds over the earth and the rainbow appears in the clouds, I will remember my covenant between me and you and all living creatures of every kind. Never again will the waters become a flood to destroy all life.” Genesis 9:12-17.

Which meant poor Noah wouldn’t have to go through all that ark-building and animal herding again.

Anyway, things like rainbows, and light refraction, and visible and invisible light, are about as amazing as it gets. Yeah, sure, Noah gathered up all the creatures in the world and crammed them onto a wooden boat he built by himself. And I’d say that just getting two cats up the gangplank was darn near a miracle. But compared with two inverted rainbows? No contest, in my view.