This Week in Science: Rainbow Clouds?

Have you seen the footage of that crazy rainbow cloud in China? It almost looks fake, like a Hollywood special effect, but it’s not. It’s called a pileus cloud or “scarf cloud.” A wispy cloud forms above a cumulus cloud, and the light gets diffracted by tiny ice crystals inside it, and that’s what causes the rainbow effect. And in this particular case, the sun was setting right behind it. Pretty funky, and very cool.