Active asteroids

dwarf planet in the Solar System and largest asteroid of the main asteroid belt

near-Earth asteroid of highest impact hazard

Apollo asteroid notable for its very small perihelion and for being the progenitor of the Geminid meteor shower

main-belt asteroid

main-belt asteroid

small body of the Solar System considered both an asteroid and a comet

asteroid

asteroid

Dimorphos (formal designation (65803) Didymos I; provisional designation S/2003 (65803) 1) is a natural satellite or moon of the near-Earth asteroid 65803 Didymos, with which it forms a binary system. The moon was discovered on 20 November 2003 by Petr Pravec in collaboration with other astronomers worldwide. Dimorphos has a diameter of across its longest extent.

bodies orbiting within the main asteroid belt which have shown cometary activity during part of their orbit

asteroid

asteroid and main-belt comet

311P/PanSTARRS, also known as P/2013 P5 (PanSTARRS), is an active asteroid and Encke-type comet discovered by Bryce T. Bolin using the Pan-STARRS telescope on 27 August 2013. Observations made by the Hubble Space Telescope revealed that it had six comet-like tails. The tails are suspected to be streams of material ejected by the asteroid as a result of a rubble pile asteroid spinning fast enough to remove material from it. This is similar to 331P/Gibbs, which was found to be a quickly-spinning rubble pile as well.

Periodic comet

354P/LINEAR, provisionally designated P/2010 A2 (LINEAR), is a small main-belt asteroid that was impacted by another asteroid sometime before 2010. It was discovered by the Lincoln Near-Earth Asteroid Research (LINEAR) at Socorro, New Mexico on 6 January 2010. The asteroid possesses a dusty, X-shaped, comet-like debris trail that has remained nearly a decade since impact. This was the first time a small-body collision had been observed; since then, minor planet 596 Scheila has also been seen to undergo a collision, in late 2010. The tail is created by millimeter-sized particles being pushed ba

238P/Read (P/2005 U1) is a main-belt comet discovered on 24 October 2005 by astronomer Michael T. Read using the Spacewatch 36-inch telescope on Kitt Peak National Observatory. It has an orbit within the asteroid belt and has displayed the coma of a traditional comet. It fits the definition of an Encke-type comet with (TJupiter > 3; a Jupiter).

active asteroid in the outer region of the asteroid belt

331P/Gibbs (P/2012 F5) is a small periodic Encke-type and rare main-belt comet, discovered by American amateur astronomer Alex Gibbs.

comet

disintegrated active main-belt asteroid

259P/Garradd is a Jupiter-family comet and active asteroid with an orbital period of 4.5 years. It was discovered in images obtained on 2 September 2008 as part of the Siding Spring Survey by Gordon J. Garradd.

REDIRECT List of numbered comets#313P