Sun dog

This article is about the atmospheric phenomenon. For other uses, see Sun dog (disambiguation).
"Parhelion" redirects here. Not to be confused with perihelion, the inner orbital extreme of a planetary body.

Very bright sun dogs in Fargo, North Dakota. Also visible are parts of the 22° halo (the arcs passing through each sun dog), a sun pillar (the vertical line), and the parhelic circle (the horizontal line).

A sun dog (or sundog) or mock sun, also called a parhelion[1] (plural parhelia) in atmospheric science, is an atmospheric optical phenomenon that consists of a bright spot to one or both sides of the Sun. Two sun dogs often flank the Sun within a 22° halo.

The sun dog is a member of the family of halos caused by the refraction of sunlight by ice crystals in the atmosphere. Sun dogs typically appear as a pair of subtly colored patches of light, around 22° to the left and right of the Sun, and at the same altitude above the horizon as the Sun. They can be seen anywhere in the world during any season, but are not always obvious or bright. Sun dogs are best seen and most conspicuous when the Sun is near the horizon.

  1. ^ "American Heritage Dictionary Entry — parhelion". The American Heritage Dictionary of the English Language. Retrieved 16 May 2017.