Where do rainbows come from? Is there a special fairy up in the sky who paints the rainbow onto the sky using her magic paintbrush? Or do the colors fall out a big bag of candy that somebody spills out of a plane??
To understand where rainbows come from, first you have to understand where color comes from; color is the way our eyes interpret the energies contained within a beam of light. White (uncolored) light contains a large spectrum of colors. When light touches an object, some of these energies are absorbed (taken in) by it, and others are reflected (cast back). – It’s the energies that are reflected which your eyes collect and then interpret as a specific color!
But the situation with reflected and absorbed colors is a little different when the object being hit by light is a droplet of water: When light hits something like a droplet of water from the right angle, it bends and splits the energies so that when they’re reflected back at you, they’re fanned out into the colorful display of a rainbow! That’s why rainbows mostly come out after it rains and there are more water droplets for light to hit! – Neat!!