Fog bows, sometimes called white rainbows, are extremely rare meteorological phenomena that we can observe in particularly targeted places like the mountains or Arctic waters.

Unlike its rainbow cousin, the white colour is owed to the much smaller size of the water drops that lead to its creation (less than .05mm). The observation of a fog bow depends on a number of factors involving the sun’s position, the size of the fog’s cloud, and the position of the observer. Generally speaking, the sun must be at a maximum 40° high in order for you to be able to see a fog bow.

Their ghostly aspect and the rareness of seeing them give this optic phenomenon an incredibly mysterious beauty.

Photo source : Janne, http://flic.kr/p/ams2eh , (CC BY-SA 2.0)

Video : Fog bow, by Don Whitaker