Sundog Over Bucegi Mountains

Provided and Copyright by: Curtasu Mihai, Romanian Society for Meteors and Astronomy (SARM)
Summary Author and Editor: Curtasu Mihai, Jim Foster

This photo showing a particularly brilliant parhelion or sundog was taken from near the Bucegi Mountains in Romania on the morning of December 29, 2007. When cirrus type clouds are in the vicinity of the Sun, parhelia or sundogs may appear if these clouds consist of plate shaped ice crystals aligned with their flat faces horizontal. Sundogs are found at the same solar altitude as the Sun and approximately 22 degrees to the left and or right of it. The 22 degree angle results from the minimum deviation of light through 60 degree prisms. Note the bright white "tail" protruding to the right of this sundog counter to the direction of the Sun. Such tails are common features of sundogs.