Sundog! Sundogs are atmospheric phenomena that look like bright spots on either side of the sun. They usually formed by hexagonal ice crystals in cirrus clouds.See a relevant photo here.
Canon EOS 550D, 28/10/2011 17:09, Shutter Speed 1/1600, Aperture Value 9.0, ISO 100, Lens Canon EF70-200mm f/4L USM, Focal  Length 200.0 mm