Meteor and other phenomena. This artwork dates from 1846. At left is the bright streak of a meteor, originating from a group of stars in the night sky, and with an arrow showing the celestial south-north direction. Meteors are fragments of space rocks burning up in the atmosphere. At right, are various forms of what appear to be lunar halos. Like solar halos, these are an optical phenomena that form when moonlight passes through ice crystals in the sky. The wavy lines may be a rare type of halo called an upper tangent arc, and the V-shaped line may be the even rarer lower tangent arc. These observations were made from Cambridge, England.