|Discovered by||Ernst Tempel and Horace Parnell Tuttle|
|Discovery date||December 19, 1865|
|1366 U1; 1699 U1;
1699 II; 1865 Y1;
1866 I; 1965 M2;
1965 IV; 1965i;
|Orbital characteristics A|
|Epoch||March 8, 1998 (JD 2450880.5)|
|Semi-major axis||10.3345 AU|
|Orbital period||33.2226 a|
|Last perihelion||February 28, 1998|
|Next perihelion||May 20, 2031|
55P/Tempel–Tuttle (commonly known as Comet Tempel–Tuttle) is a periodic comet with an orbital period of 33 years. It fits the classical definition of a Halley-type comet with (20 years < period < 200 years). It was independently discovered by Ernst Tempel on December 19, 1865 and by Horace Parnell Tuttle on January 6, 1866.
It is the parent body of the Leonid meteor shower. In 1699, it was observed by Gottfried Kirch but was not recognized as a periodic comet until the discoveries by Tempel and Tuttle during the 1866 perihelion. In 1933, S. Kanda deduced that the comet of 1366 was Tempel–Tuttle, which was confirmed by Joachim Schubart in 1965. On 26 October 1366, the comet passed 0.0229 AU (3,430,000 km; 2,130,000 mi) from Earth.
The orbit of 55P/Tempel–Tuttle intersects that of Earth near exactly, hence streams of material ejected from the comet during perihelion passes do not have to spread out over time to encounter Earth. This coincidence means that streams from the comet at perihelion are still dense when they encounter Earth, resulting in the 33 year cycle of Leonid meteor storms. For example, in November 2009, the earth passed through meteors left behind mainly from the 1466 and 1533 orbit.
- Seiichi Yoshida (2005-12-12). "55P/Tempel-Tuttle". Seiichi Yoshida's Comet Catalog. Retrieved 2012-02-18.
- C&MS: 55P/Tempel-Tuttle
- "Closest Approaches to the Earth by Comets". Minor Planet Center. Retrieved 2012-06-28.
- BBC News (November 17, 2009). "Star gazers hoping for clear sky". Archived from the original on 17 November 2009. Retrieved 2009-11-17.
- David C. Jewitt. "From Cradle To Grave: The Rise and Demise of the Comets" (PDF). Comets II. Retrieved 2009-11-12.
|Periodic comets (by number)|