Parhelia Above Lecce, Italy

May 23, 2010

SunDogs at Leece

Photographer: Livio Ruggiero
Summary Author: Livio Ruggiero; Jim Foster

The photo above shows two low lying sundogs (parhelia) taken at sunset above the University of Salento stadium in Lecce, Italy. When plate-shaped, hexagonal ice crystals in cirrus type clouds are oriented horizontally, sunlight may be focused in such a way as to create bright and colorful patches of light 22 degrees on either side of the Sun. For this to occur, light must enter through one of the crystal’s side faces and exit through an alternate side face.  In many cases, only one patch (parahelion) is visible, but on this spring evening, each could clearly be seen. Always be sure to protect your eyes when looking toward the Sun. Photo taken on May 4, 2005.