Comet

A comet is a small body in the solar system that orbits the sun and (at least occasionally)

Peculiar comets

Of the thousands of known comets, some are very unusual. Comet Encke orbits from inside the orbit of Jupiter to inside the orbit of Mercury while Comet 29P/Schwassmann-Wachmann orbits in a nearly circular orbit entirely between Jupiter and Saturn.{{hnote|Kronk, '29P/Schwassmann-Wachmann 1'}} 2060 Chiron, whose unstable orbit keeps it between Saturn and Uranus, was originally classified as an asteroid until a faint coma was noticed.{{hnote|Kronk, '95P/Chiron'}} Similarly, Comet Shoemaker-Levy 2 was originally designated asteroid 1990 UL3.{{hnote|Kronk, '137P/Shoemaker-Levy 2'}} Some near-earth asteroids are thought to be extinct nuclei of comets which no longer experience outgassing.

Related Topics:
Mercury - 29P/Schwassmann-Wachmann - Saturn - 2060 Chiron - Uranus - Comet Shoemaker-Levy 2 - 1990 UL₃ - Near-earth asteroid

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Some comets have been observed to break up. Comet Biela was one significant example, breaking into two during its 1846 perihelion passage. The two comets were seen separately in 1852, but never again after that. Instead, spectacular meteor showers were seen in 1872 and 1885 when the comet should have been visible. A lesser meteor shower, the Andromedids, occurs annually in November, and is caused by the Earth crossing Biela's orbit http://comets.amsmeteors.org/meteors/showers/andromedids.html.

Related Topics:
Comet Biela - 1846 - 1852 - 1872 - 1885

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Several other comets have been seen to break up during their perihelion passage, including great comets West and Comet Ikeya-Seki. Some comets, such as the Kreutz Sungrazers, orbit in groups and are thought to be pieces of a single object that has previously broken apart.

Related Topics:
Comet Ikeya-Seki - Kreutz Sungrazers

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Another very significant cometary disruption was that of Comet Shoemaker-Levy 9, which was discovered in 1993. At the time of its discovery, the comet was in orbit around Jupiter, having been captured by the planet during a very close approach in 1992. This close approach had already broken the comet into hundreds of pieces, and over a period of 6 days in July 1994, these pieces slammed into Jupiter's atmosphere — the first time astronomers had observed a collision between two objects in the solar system.{{hnote|Kronk, 'D/1993 F2 Shoemaker-Levy 9'}} However, it has been suggested that the object responsible for the Tunguska event in 1908 was a fragment of Comet Encke.

Related Topics:
Comet Shoemaker-Levy 9 - 1993 - 1992 - 1994 - Tunguska event - 1908

~ ~ ~ ~ ~ ~ ~ ~ ~ ~