What is this rainbow that formed without any rain?
This photo is taken of a sundog. In scientific terms, it's called a parhelion. They form in pairs, at roughly 22 degrees on both sides of the sun at the same elevation. They are caused by the refraction of sunlight passing through ice crystals. They are most commonly seen during winter in the middle latitudes and are exclusively associated with cirrus clouds. They are also known as mock suns.