Main-belt Comet

Main-belt Comet

Main-belt comets are bodies orbiting within the main asteroid belt which have shown cometary activity during part of their orbit. The Jet Propulsion Laboratory defines a main-belt asteroid as an asteroid with a semi-major axis (average distance from the Sun) of more than 2 AU but less than 3.2 AU, and a perihelion (closest approach distance to the Sun) of no less than 1.6 AU.

The first MBC was thought to be an asteroid when discovered and was named 1979 OW7. In 1996 it was found to have a tail by Eric Elst and Guido Pizarro. It is now given the cometary designation 133P/Elst-Pizarro.