Image Credit NASA, ESA, and D. Jewitt (University of California, Los Angeles). Photo No. STScI-2010-07
Comet P 2010/A2 was always a strange beast, one of the few known comets that orbited in the main asteroid belt. Well, turns out to be weirder than that, a close-up view from the Hubble Space telescope suggests that the tail of P 2010. A2 is not a cometary tail, but a debris tail resulting from the collision of two asteroids. See also here.