Discovery [1] | |
---|---|
Discovered by | Siding Spring Observatory |
Discovery date | October 10, 2004 |
Designations | |
P/2004 TU12 | |
Orbital characteristics [2] | |
Epoch | 27 October 2010 |
Aphelion | 4.873 AU |
Perihelion | 1.233 AU |
Semi-major axis | 3.053 AU |
Eccentricity | 0.5961 |
Orbital period | 5.33 years |
Inclination | 27.817° |
Last perihelion | 7 December 2020 |
Next perihelion | 17 May 2026 |
TJupiter | 2.792 |
Earth MOID | 0.239 AU |
Physical characteristics | |
Dimensions | 14.06 ± 0.96 km [3] |
32.86 hours [4] | |
0.022 ± 0.003 [4] | |
Comet total magnitude (M1) | 15.2 |
162P/Siding Spring is a Jupiter-family comet with an orbital period of 5.3 years. It was discovered in images obtained on 10 October 2004 as part of the Siding Spring Survey. [1]
The comet was discovered during the Siding Spring Survey as an asteroidal object shining with an apparent magnitude of 14.1 but a tail extending for about 4 arcminutes was observed on 12 November 2004, indicating that it is a comet. [1] The tail grew longer the next days, reaching a length of over 10 arcminutes on 15 November. Two days later the tail was fainter, and bearly visible within one arcminute from the nucleus. [5] On 21 October 2031 the comet will approach Earth at a distance of 0.2456 AU (36.74 million km). [2]
The comet was observed by NASA Infrared Telescope Facility in 2004, finding that the nucleus has an effective radius of 6.0 ± 0.8 km, which corresponds to a visual albedo of 0.034 ± 0.014, [6] and a reflectance spectrum typical of a D-type asteroid. [7] Further observations by the Spitzer Space Telescope indicate an effective radius of 7.03 ± 0.48 km. [3] This is one of the largest nuclei of Jupiter family comets with known radius. [6] More detailed observations indicate that the nucleus has axis ratios a/b = 1.56 and b/c = 2.33, and could possibly have two lobes. [4] The sidereal period of the comet is 32.864 ± 0.001 hours. [4]
2060 Chiron is a ringed small Solar System body in the outer Solar System, orbiting the Sun between Saturn and Uranus. Discovered in 1977 by Charles Kowal, it was the first-identified member of a new class of objects now known as centaurs—bodies orbiting between the asteroid belt and the Kuiper belt. Chiron is named after the centaur Chiron in Greek mythology.
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121P/Shoemaker–Holt, also known as Shoemaker-Holt 2, is a periodic comet in the Solar System with an orbital period of about 8 years. The comet was discovered by Carolyn S. Shoemaker, Eugene M. Shoemaker, and Henry E. Holt on 9 March 1989. The comet then had an apparent magnitude of 13, was diffuse and had a tail about 2 arcminutes long.
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20898 Fountainhills (provisional designation 2000 WE147) is a dark asteroid in a cometary orbit (ACO) from the outermost regions of the asteroid belt, approximately 37 kilometers (23 miles) in diameter. It was discovered on 30 November 2000, by American amateur astronomer Charles W. Juels at the Fountain Hills Observatory in Arizona, United States. The D-type asteroid has a rotation period of 12.84 hours. It was named for the city of Fountain Hills, Arizona, in the United States.
1362 Griqua, provisional designation 1935 QG1 is a dark, Jupiter-resonant background asteroid on an eccentric, cometary-like orbit and the namesake of the Griqua group, located in the Hecuba gap in the outermost region of the asteroid belt. The carbonaceous asteroid measures approximately 28 kilometers (17 miles) in diameter and has a rotation period of 6.9 hours. It was discovered on 31 July 1935, by South-African astronomer Cyril Jackson at Union Observatory in Johannesburg. The asteroid was named after the Griqua people in South Africa and Namibia.
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93P/Lovas, also called Comet Lovas 1, is a Jupiter-family comet with an orbital period of 9.2 years. It was discovered in 1980 by Hungarian astronomer Miklós Lovas.
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126P/IRAS is a periodic comet with an orbital period of 13.4 years. It was discovered in images taken by the Infrared Astronomical Satellite (IRAS) on 28 July 1983 by J. Davies. The discovery was confirmed with images taken with the 1.2-m Schmidt telescope at Palomar Observatory.
156P/Russell–LINEAR is a Jupiter family periodic comet with an orbital period of 6.4 years. It was discovered by Kenneth S. Russell in September 1986.
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