Though sun halos can happen year-round, they are especially noticeable in the winter when ice-filled cirrus clouds are more common.

A mysterious halo around the sun isn’t just a beautiful sight—it could be a warning. Learn the science and ancient beliefs behind this rare phenomenon and why it might signal an approaching storm.

A cool sight: Thank you to Adam for sending through this 'sun halo' over Leckhampton Hill. Halos are caused by ice crystals in the air which are usually associated with high-altitude cirrus clouds.

Hong Kong on Tuesday witnessed a rare natural phenomenon, a halo around the sun, that can be experienced only when meteorological conditions are right. The Observatory posted pictures on its ...