Parhelia.

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Parhelia (sundogs or mock suns) are bright colorful spots in cirrus clouds. They are found at the same altitude as the sun and never less than 22 degrees from it. They are usually a few degrees across and may be extended either vertically or horizontally. Parhelia usually come in pairs, one on each side of the sun, and are quite common.
They are reddish on the side facing the sun and often have bluish-white tails stretching horizontally away from them. Parhelia are formed by refraction of light between 60 degree prism faces in horizontally oriented plates.


 
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