For other uses, including the video games, see Halo (disambiguation).
A halo (also known as a nimbus or Gloriole) is a ring of light that surrounds an object. They are often used in religious works to depict holy or sacred figures. In Christian sacred art (Eastern and Western churches), holy persons ( saints) are depicted with a halo, a golden, yellow or white circular glow, around the head.
Halos, also known as icebows, are also optical phenomena that appear near or around the Sun or Moon, and sometimes near other strong light sources such as street lights. There are many types of optical halos, but they are mostly caused by ice crystals in cold cirrus clouds located high (5-10 km, or 3-6 miles) in the upper troposphere. The particular shape and orientation of the crystals is responsible for the type of halo observed. Light is reflected and refracted by the ice crystals and may split up into colors because of dispersion, similarly to the rainbow.
The halo has become an object of religious iconography in both Christian and Buddhist traditions.
The halo represents an aura or glow of sanctity which was most prominent around the head and was conventionally drawn as a circle. It first appeared culture in the art of ancient Greece and Rome, and was incorporated into Christian art sometime in the 4th century.
Round halos are typically used to signify saints —ie. people considered as spiritually gifted. A cross within a halo is used to represent Jesus. Triangular halos are used for representations of the Trinity. Square halos are used to depict unusually saintly living personages.