A 22° halo[a] seen around the sun. The halo itself is formed by ice crystals suspended in the air, and the "22°" part refers to the angular distance between the sun and the ring, which is dependent on the shape of the crystals. Worth mentioning here is the painting of Stockholm called Vädersolstavlan[b], which depicts multiple halo displays over the city seen on the morning of April 20, 1535.
2010-12-08 12:47