Sundogs Over Concordia Research Station, Antarctica

July 03, 2014

Sun Dogs above Dome Circe, Antarctica

Photographer: Adrianos Golemis
Summary Authors: Adrianos Golemis; Jim Foster

This photograph depicts the Sun accompanied by two pronounced sundogs above the infinite white of Dome Circe, in the heart of Antarctica. It was captured late in the day on February 11, 2014, from Concordia Research Station, situated at an altitude of 10,607 ft (3,233 m). Sundogs, also called parhelia or mock suns, occur on both or either side of the Sun -- at the same solar altitude. These colorful concentrations of refracted sunlight result when sunlight is bent by similarly oriented, six-sided plate-shaped ice crystals. In most locations such crystals are found in cirrus clouds, but in high-latitude regions they may occur as diamond dust, slowly falling toward the surface.

At this latitude (75 degrees south) the long polar night began May 5. There will be no sunrise or sunset until the middle of August. However, there are a few hours of astronomical twilight each day.

Photo Details: Camera: Canon EOS 450D; Lens: EF-S18-55mm f/3.5-5.6 IS; Focal Length: 18.0mm; Aperture: f/13.0; Exposure Time: 0.0025 s (1/400); ISO equiv: 200. Photo taken at 2:58 p.m.