<P> Halo ( from Greek ἅλως , halōs ) is the name for a family of optical phenomena produced by light interacting with ice crystals suspended in the atmosphere . Halos can have many forms , ranging from colored or white rings to arcs and spots in the sky . Many of these are near the Sun or Moon , but others occur elsewhere or even in the opposite part of the sky . Among the best known halo types are the circular halo ( properly called the 22 ° halo ) , light pillars and sun dogs , but there are many more ; some of them fairly common , others ( extremely ) rare . </P>
sun 's halo is produced by the refraction of light in
ice crystals suspended in the atmosphere