Sundog Light Phenomenon, Manitoba, Canada, 2005
Photograph by Norbert Rosing

A solar phenomenon known as a sundog arcs (幻日弧) over the tundra (苔原) in Churchill, Manitoba, Canada. Sundogs are fairly common occurrences in the Arctic and Antarctic. They form when the sun is near the horizon and ice crystals high in the sky line up in a way that bends the solar rays like a prism (菱镜).

- National Geographic