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Sundog "Comet" by Nicole Ebalo

2nd Place - Natural Category

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School: Charles Wright Academy

Teacher: Mr. Jon Lamoreux

This picture was taken in the late afternoon of a cold spring day as the sun was setting. The phenomenon seen in the center of the picture is a sundog with a bit of a light tail. The sundog-tail combination resembles a comet shooting through the sky. Sundogs, scientifically known as parhelia, appear when sunlight passes through ice crystals in the air. These hexagonal ice crystals, which must be oriented at just the right angle relative to an observer, separates sunlight into the rainbow spectrum. The separation is caused by a process called refraction. Because the ice crystals? refractive index is generally higher than that of the cold air, sunlight bends as it passes through the ice crystals. Sunlight is made up of the whole color spectrum, however, and consequently each color bends at a slightly different angle than the others due to varying wavelengths.

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