Transition Objects
Objects that blur the line between asteroid and comet — active asteroids and dormant comets.
- (196256) 2003 EH1(196256)
An asteroid on a short-period, comet-like orbit believed to be a dormant or extinct comet nucleus — the parent body of the sharp, brief Quadrantid meteor shower.
TypeTransition objectDiscovered2003 - 3200 Phaethon(3200)
A near-Earth asteroid that brightens and sheds dust as it passes very close to the Sun — a 'rock comet' — and the parent body of the Geminid meteor shower, unusual for a shower whose source is an asteroid rather than a comet.
TypeTransition objectDiscovered1983 - 3552 Don Quixote(3552)
A large near-Earth object on a comet-like orbit long suspected to be a dormant comet; faint carbon-dioxide activity was detected in 2013, suggesting it is not fully extinct.
TypeTransition objectDiscovered1983 - 7968 Elst–Pizarro(7968)
The prototype main-belt comet — an object on an ordinary asteroid-belt orbit that repeatedly develops a comet-like tail, carrying both an asteroid number and a comet designation.
TypeTransition objectDiscovered1996