Isn’t that something! Actually somethings. A double rainbow. The day was sunny. There was a cloudburst. Out came the sun again. And rainbows appeared.
The bright rainbow is a primary rainbow. In a primary rainbow, the arc shows red on the outer part and violet on the inner part. From what I’ve been reading, a primary rainbow appears when light is refracted as it enters a water droplet and then it’s reflected (somehow) on the back of the droplet and gets refracted again as it leaves the droplet. Light. Such a trickster.
In a double rainbow, a second arc, the one higher in the sky, has the order of its colors reversed, with red on the inner side of the arc. This is light playing with a water droplet again. Somehow the light is reflected twice on the inside of the droplet before it exits. Light. Such a show-off.
Here’s another slice of rainbow on the same afternoon.