The following is a list of comets that have been assigned a numeric designation by the Minor Planet Center, having been observed on at least two occasions. As of June 2016 there are 337 numbered comets, 310 being Jupiter-family comets, 20 Halley-type comets, 6 main-belt comets and one long-period comet (153P/Ikeya–Zhang). The letter to the left of the forward slash in the designation indicates the comet type, either P (Periodic), C (Non-periodic), X (No orbit) or D (Lost).
A number of the comets on the list had been discovered prior to observations of cometary activity, and were assigned asteroid designation, such as 133P/Elst–Pizarro, which had prior been given the minor planet numeric designation 7968. A few, through various reasons, display characteristics of both an asteroid and a comet, such as 95P/Chiron.
Occasionally, comets will break up into smaller chunks, as volatiles coming off the comet may cause it to break into two or more pieces. An extreme example of this is 73P/Schwassmann–Wachmann, which broke into over 50 pieces during its 1995 perihelion.
For a list of unnumbered Jupiter-family and Halley-type comets, see List of periodic comets.
73P/Schwassmann–Wachmann
A certain comet, designated 73P/Schwassmann–Wachmann, broke up into several pieces in 1995, and as of its last perihelion date, the pieces numbered at least 67 with 73P/Schwassmann–Wachmann C as the presumed original nucleus. Because of the enormous number, the pieces of it have been compiled into a separate list: