153P/Ikeya–Zhang
Comet Ikeya–Zhang photographed by Philipp Salzgeber on 1 April 2002 | |
| Discovery | |
|---|---|
| Discovered by | Kaoru Ikeya Zhang Daqing |
| Discovery date | 1 February 2002 |
| Designations | |
| |
| Orbital characteristics | |
| Epoch | 8 May 2002 (JD 2452402.5) |
| Observation arc | 341–1,125 years |
| Earliest precovery date | February 877 3 February 1661 |
| Number of observations | 1,893 |
| Aphelion | 101.73 AU |
| Perihelion | 0.507 AU |
| Semi-major axis | 51.119 AU |
| Eccentricity | 0.99008 |
| Orbital period | 365.49 years |
| Max. orbital speed | 59 km/s (2002-03-18) |
| Min. orbital speed | 0.29 km/s (2182-Nov-24) |
| Inclination | 28.121° |
| 93.369° | |
| Argument of periapsis | 34.668° |
| Mean anomaly | 0.135° |
| Last perihelion | 18 March 2002 29 January 1661 |
| Next perihelion | 1 September 2362 14 March 2363 |
| TJupiter | 0.879 |
| Earth MOID | 0.332 AU |
| Jupiter MOID | 0.011 AU |
| Physical characteristics | |
Mean diameter | 5.09 km (3.16 mi) |
| 1.48±0.2 days | |
| Comet total magnitude (M1) | 4.0 |
| 2.9 (2002 apparition) | |
Comet Ikeya–Zhang (Japanese, Chinese: 池谷-張彗星, officially designated 153P/Ikeya–Zhang) is a long-period comet discovered independently by two astronomers from Japan and China in 2002. It has by far the longest orbital period of the numbered periodic comets. It was last observed in October 2002 when it was about 3.3 AU (490 million km) from the Sun.