Editing Lists of comets (section)

{{Short description|None}}
[[File:S0484.4.jpg|thumb|300px|right|Coin showing [[Caesar's Comet]] as a star with eight rays, tail upward]]
Non-periodic [[comet]]s are seen only once.  They are usually on near-[[parabolic orbit]]s that will not return to the vicinity of the [[Sun]] for thousands of years, if ever.

Periodic comets usually have elongated [[elliptical orbit]]s, and usually return to the vicinity of the Sun after a number of decades.

The official names of non-periodic comets begin with a "C"; the names of periodic comets begin with "P" or a number followed by "P".  [[Lost comets|Comets that have been lost]] or disappeared have names with a "D". Comets whose orbit has not been determined are designated with a "X" prefix.