Comet nucleus of 9P/Tempel as imaged by the NASA Deep Impact space probe. This is not yet extinct but gives some idea of a cometary nucleus
An extinct comet is a comet that has expelled most of its volatile ice and has little left to form a tail and coma. In a dormant comet, rather than being depleted, any remaining volatile components have been sealed beneath an inactive surface layer.
Due to the near lack of a coma and tail, an extinct or dormant comet may resemble an asteroid rather than a comet and blur the distinction between these two classes of small Solar System bodies. When volatile materials such as nitrogen, water, carbon dioxide, ammonia, hydrogen and methane in the comet nucleus have evaporated away, all that remains is an inert rock or rubble pile. A comet may go through a transition phase as it comes close to extinction.
An extinctcomet is a comet that has expelled most of its volatile ice and has little left to form a tail and coma. In a dormant comet, rather than being...
being flung to interstellar space. The appearance of a comet is called an apparition. Extinctcomets that have passed close to the Sun many times have lost...
sub-kilometer-sized carbonaceous asteroid that is thought to be an extinctcomet. It is classified as near-Earth object and potentially hazardous asteroid...
such as Comet Shoemaker–Levy 9, which collided with Jupiter in 1994. Brian G. Marsden, comet-orbit expert Extinctcomet List of periodic comets List of...
rotation period of 7.7 hours. Due to its comet-like orbit and albedo, Don Quixote has been suspected to be an extinctcomet. However, infrared observations with...
(probability of 17%). Proponents of the comet hypothesis have suggested that the object was an extinctcomet with a stony mantle that allowed it to penetrate...
The nucleus is the solid, central part of a comet, formerly termed a dirty snowball or an icy dirtball. A cometary nucleus is composed of rock, dust,...
2016 WF9 is a dark, sub-kilometer asteroid and suspected extinctcomet, classified as near-Earth object and potentially hazardous asteroid of the Apollo...
Uccle in 1936, it became a lost asteroid until 1977. It may also be an extinctcomet and a source of meteor showers. It was named after Adonis from Greek...
(26–43 ft) in diameter. The impactor may have been an asteroid, comet, centaur, extinctcomet, or temporary satellite capture. The impact happened 3 June...
high orbital inclination and eccentricity suggest 2015 TB145 may be an extinctcomet that has shed its volatiles after numerous passes around the Sun. Orbital...
come from the Oort cloud, with a roughly equal probability of being an extinctcomet and a rocky body that was originally scattered into the Oort cloud....
Chapter 5 ("Asteroids and Comets in our Backyard") exhaustively catalogs the types of near-Earth objects (asteroids and extinctcomets whose orbits intersect...
classified as a large near-Earth object of the Apollo group. It may be an extinctcomet or damocloid asteroid. The asteroid was discovered on 29 April 2009...
confinement to the inner Solar System (see extinctcomet). It is suggested that these main-belt asteroid-comets are evidence of a recent impact exposing...
asteroids; "asteroids" with notably eccentric orbits are probably dormant or extinctcomets. For almost two centuries, from the discovery of Ceres in 1801 until...
likely extinctcomets and consist largely of water ice. Similarly, Jupiter-family comets, and possibly near-Earth asteroids that are extinctcomets, might...
its orbit more closely resembles that of a comet than an asteroid; it has been referred to as a "rock comet". In studies performed by NASA's STEREO spacecraft...
retrograde orbit from the outer Solar System, suggesting that it is an extinctcomet. It was first observed on 1 June 2013 by astronomers with the Pan-STARRS...
orbits but show comet-like visual characteristics. That is, they show a coma, tail, or other visual evidence of mass-loss (like a comet), but their orbits...
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