81P/Wild
< 81P
| Discovery | |
|---|---|
| Discovered by | Paul Wild |
| Discovery site | Zimmerwald, Switzerland |
| Discovery date | 6 January 1978 |
| Designations | |
| P/1978 A2; P/1983 S1 | |
| 1978 XI; 1984 XIV; 1990 XXVIII | |
| Orbital characteristics | |
| Epoch | 17 October 2024 (JD 2460600.5) |
| Observation arc | 46.67 years |
| Number of observations | 7,963 |
| Aphelion | 5.307 AU |
| Perihelion | 1.597 AU |
| Semi-major axis | 3.452 AU |
| Eccentricity | 0.53739 |
| Orbital period | 6.414 years |
| Inclination | 3.237° |
| 136.09° | |
| Argument of periapsis | 41.568° |
| Mean anomaly | 103.17° |
| Last perihelion | 15 December 2022 |
| Next perihelion | 14 May 2029 |
| TJupiter | 2.879 |
| Earth MOID | 0.601 AU |
| Jupiter MOID | 0.012 AU |
| Physical characteristics | |
| Dimensions | 5.5 km × 4.0 km × 3.3 km (3.4 mi × 2.5 mi × 2.1 mi) |
| Mass | 2.3 x 1013 kg (5.1 x 1013 lb) |
Mean density | 0.6 g/cm3 (37 lb/cu ft) |
| Comet total magnitude (M1) | 9.8 |
| Comet nuclear magnitude (M2) | 12.9 |
Comet 81P/Wild, also known as Wild 2 (pronounced "vilt two") (/ˈvɪlt/ VILT), is a comet with a period of 6.4 years named after Swiss astronomer Paul Wild, who discovered it on January 6, 1978, using a 40-cm Schmidt telescope at Zimmerwald, Switzerland.
For most of its 4.5 billion-year lifetime, Wild 2 probably had a more distant and circular orbit. In September 1974, it passed within 1.0 million km (0.62 million mi) of the planet Jupiter, the strong gravitational pull of which perturbed the comet's orbit and brought it into the inner Solar System. Its orbital period changed from 43 years to about 6 years, and its perihelion is now about 1.59 AU (238 million km).