Why are rainbows curved?: Quick Facts

Written and fact-checked by

The Information Architects of Encyclopaedia Britannica

Photos

A vivid rainbow arches across the sky above a grassy field at sunset, with the sun low on the horizon and soft clouds in the background.

$Diagram showing sunlight entering a water droplet, refracting, reflecting inside it, and emerging as separated red-to-violet light. Rays reaching an observer at about 42 degrees for red and 40 degrees for violet form a rainbow opposite the sun.$

See All Images →

Topics

rainbow refraction What causes a rainbow?What causes mirages?double refraction Snell’s law mirage refractive index Halo atmospheric refraction