Sun Dog

 

The photograph above is a great example of an optical phenomena known in the science of meteorology as sun dogs. The bands of color seen in the clouds above are produced when the suns rays are refracted by plate shaped hexagonal ice crystals that compose cirrus clouds. The ice crystals act as prisms that bend the suns rays as they pass through. This causes the white light we normally observe to be separated into its component colors, giving the sun dog the appearance of a rainbow. If the ice crystals are randomly oriented, a complete ring, or halo, will be seen around the sun. More often than not, however, the ice crystals become vertically oriented as they fall, giving rise to sundogs, which appear off to the sides of the sun. Sun dogs are red in color on the side nearest the sun, with colors further away from the sun ranging from orange to blue. Sun dogs typically appear to the left and right of the sun and at the same elevation angle above the horizon as the sun. Sun dogs are usually seen most clearly when the sun is low in the sky.



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