Provided by: David Wigglesworth, Schomberg Veterinary Services

Summary authors & editors: David Wigglesworth

This photo showing a bright yellow Sun pillar was taken at 7:50 a.m. (Eastern Standard Time) on December 17, 2004, from Schomberg, Ontario. The pillar was observed just a few minutes after sunrise -- the morning was colder than normal for this time of year (-11 degrees C or about 12 degrees F). The spread of a pillar is a function of the extent to which the crystals wobble about their vertical axis and is unrelated to crystal size. Upper sun pillars occur when sunlight is reflected downward off of ice crystals lying above a line between the observer and the Sun.