Jeff Wilson / Sun Dog, or Parhelion, caused by refraction of the sun's rays, more commonly seen in Antarctica, above glacier, Dry Valleys, Antarctica, December 2009. Taken on location for the BBC series, Frozen Pla...

Bryan and Cherry Alexander / Polar bear (Ursus maritimus) mother and cubs with Parhelion / sun dogs over sea ice. Churchill, Manitoba, Canada.

Neil Lucas / Sundog / Parhelion (circle of light around the sun) with large ice fumerole in the foreground, McMurdo Sound, Ross Sea, Antarctica, November 2008

Jim Brandenburg / Sundogs, also known as mock sun, with snow field, Minnesota

Doug Allan / Parhelion sun effect over Brunt ice shelf, Antarctica

Ashley Cooper / Jet stream winds blowing clouds with parhelion, over the Annapurna Himalayas, Nepal. December 2012

Fabrice Cahez / Parhelion or sundog phenomenon, caused by refraction of sunlight through ice crystals in either clouds of freezing moist air. France, December 2016.

Richard Du Toit / Sundog or parhelion phenomena, Mountain Zebra National Park, South Africa.

Bryan and Cherry Alexander / A sun dog (parhelion / parhelia) in the sky above a truck on a stormy winter's day near Sabetta in the South Tambey Gas Field, Yamal Peninsula, Siberia, Russia. February 2014.

Mark Hamblin / 2020VISION / Sun dog or Parhelion, Cairngorms NP, Scotland, UK, December 2010

Frederique Olivier / Sundog / Parhelion (circle of light around the sun) seen from the back of icebreaker 'Aurora Australis' near Mawson Station, Antarctica, February 2011.

Jeff Wilson / 'Sun Dog', or Parhelion, caused by refraction of the sun's rays, more commonly seen in Antarctica, above glacier, Dry Valleys, Antarctica, December 2009. Taken on location for the BBC series, Frozen P...

Jeff Wilson / Sun Dog, or Parhelion, visible over tent of film crew, caused by refraction of the sun's rays, more commonly seen in Antarctica, above glacier, Dry Valleys, Antarctica, December 2009. Taken on locatio...

Bryan and Cherry Alexander / Sundog / Parhelion (circle of light around the sun) at sunset in the Argentine Islands, Antarctica, February 2009.

Bryan and Cherry Alexander / Sundog / Parhelion (circle of light around the sun), on either side of herders' camp on the tundra. Yamal Peninsula, Western Siberia, Russia, 2001.

Bryan and Cherry Alexander / Sundog / Parhelion (circle of light around the sun), formed by ice crystals in the atmosphere, above icebergs, Northwest Greenland, 1998.

Bryan and Cherry Alexander / Sundog / Parhelion, circle of light around the sun, formed by ice crystals in the atmosphere, above icebergs, Northwest Greenland, 1998.

Gerry Ellis / Sundog around sun, North America

Neil Lucas / Sundog / Parhelion (circle of light around the sun) with large ice fumerole in distance, Mt Erebus, Antarctica, November 2008

Michio Hoshino / Polar Bear (Ursus maritimus) mother and cubs walking on ice field with sundog, Canada

Konrad Wothe / Spruce forest in snow with sundogs, Hudson Bay, Canada

Jeff Vanuga / Sun dog / Parhelion shinning on cold winter morning, Antelope Flats, Teton National Park, Wyoming, USA

Jim Brandenburg / Sundogs, also known as mock sun, with car on the horizon above a snow field, Minnesota

Jim Brandenburg / Sundogs, also known as mock sun, on the horizon above a snow field, Minnesota

Michio Hoshino / Polar Bear (Ursus maritimus) mother and cub, with sundog in sky, Churchill, Manitoba, Canada

Doug Allan / Parhelion sun effect over Coronation Island, South Orkneys, Antarctica

Benjamin Olson / Sundogs over road in winter, Sax-Zim Bog, Minnesota

Norbert Wu / Sundog, also known as mock suns, Antarctic Peninsula, Antarctica

Ashley Cooper / Jet stream winds high above the Annapurna Himalayas creating clouds with rainbow colours caused by light refraction on ice crystals, known as parhelion or sundog, in Nepal, South Asia. December, 2012.

Ashley Cooper / Jet stream winds high above the Annapurna Himalayas creating clouds with rainbow colours caused by light refraction on ice crystals, known as parhelion or sundog, in Nepal, South Asia. December, 2012.

Jeff Vanuga / Sun dog or parhelion forming colorful rainbow in the Grand Caynon of the Yellowstone in winter. Yellowstone National Park. Wyoming, USA. April.