Halo Over Orsta, Norway
April 04, 2010
The photo above showing a prominent 22 degree halo was taken over Orsta, Norway on March 27, 2010. When sunlight is refracted in hexagonal ice crystals having no particular orientation, eye-catching halos may result. The ice crystals producing halos are pencil shaped and are most often found in cirrus type clouds. Like all atmospheric halos the 22 degree halo is polarized, meaning that the vibrations of the light waves occur in but a single plane.
Photo details: Canon EOS 500D camera; tripod and remote controller; Sigma 15 mm fisheye lens; ISO 100; exposure time 1/4000 sec.