Sundog Pair Over Valle de Chaschuil, Argentina

May 12, 2014

Sundog Pair

Summary Author: Leandro Perez; Jim Foster
The photo above shows a beautiful sundog pair observed from the Argentinian Andes at Valle de Chaschuil, Argentina. It was taken from an altitude of 10,335 ft (3,150 m), at 7:25 p.m. on January 30, 2014. Sundogs or parhelia form at the same altitude of the Sun when sunlight refracts through hexagonal plate crystals. The prisms forming the sundogs are oriented with their large faces nearly horizontal, but the faint 22 degree halo is composed of ice crystals that are more randomly oriented. Note the white tails of the sundogs, fragments of the parhelic circle, extending away from the Sun.
Photo details: Canon 60D camera; 17mm lens; 1/800 sec. exposure; f/11; ISO 100.