|The sun halo|
Sometimes the sun looks as if through a big lens. In reality, the effect of million lenses is seen: the lenses of ice crystals. As the water in upper atmospheric layers freezes, small flat, hexagonal ice crystals could be formed. The facets of these crystals, which gradually come down to the ground, spinning, are oriented parallel to the surface most of the time. At sundown or sunrise the viewers line of sight might go through this facet, and each crystal might behave as a small lens, refracting sunlight. The combined effect might lead to a phenomenon, called parhelion, or false sun. This image was obtained in the morning of 2000, in the period of winter solstice, close to Aims, Iowa state, the USA. One can see the sun and two noticeable parhelions on the sides in the center of the picture. Behind the houses and trees one can see a halo of 22 degrees, three solar columns and the arch, created by sunlight, reflected by atmospheric ice crystals.