An Etymological Dictionary of Astronomy and Astrophysics

An atmospheric optical phenomenon appearing as a vertical shaft of light extending from the Sun or other bright light source during very cold weather.

Light pillars or → sun pillars occur when artificial light or sunlight near the horizon is reflected from falling ice crystals associated with thin, high-level clouds.

The ice crystals have a hexagonal plate shape and fall with a horizontal orientation, gently rocking from side to side as they fall.

See also: → light; → pillar.