The Refraction and Scattering of Light Caused by Ice Crystals Creates the Spectacular Sun Dogs and Halo Phenomena in Sweden.
(Video: The Figen).
The video shared by Newsweek on October 27th, recorded by a skier at the Vemdalen resort in central Sweden, showcases two circles surrounding the sun along with prominent bright spots appearing above the snow-covered mountains.
These are two rare atmospheric optical phenomena known as halos and sun dogs. While the largest bright spot in the center is the real sun, the two smaller bright spots on either side are illusions referred to as sun dogs or phantom suns.
Phantom suns occur due to the refraction and scattering of sunlight, caused by hexagonal ice crystals in the atmosphere, similar to how rainbows form through the refraction and scattering of light through droplets of varying sizes.
Phantom suns appearing along with halos in Sweden.
In this case, the ice crystals act like miniature prisms, bending the light passing through them at a minimum deviation angle of 22°. Typically, there will be a pair of bright spots symmetrically positioned on either side of the sun above the halo. The phenomenon observed in Vemdalen includes both a 22° halo (smaller) and a 46° halo (larger but fainter).
According to EarthSky, the presence of halos and phantom suns is also an indication that there are thin cirrus clouds floating at altitudes of 6 kilometers or higher, where numerous ice crystals are present. All of these phenomena are usually only observed in cold environments.
