C/1998 P1 (Williams)
Comet Williams as imaged by the European Southern Observatory on 11 August 1998 | |
| Discovery | |
|---|---|
| Discovered by | Peter Francis Williams |
| Discovery site | Heathcote, Australia |
| Discovery date | 10 August 1998 |
| Orbital characteristics | |
| Epoch | 15 December 1998 (JD 2451162.5) |
| Observation arc | 240 days |
| Number of observations | 403 |
| Aphelion | ~3,580 AU |
| Perihelion | 1.146 AU |
| Semi-major axis | ~1,800 AU |
| Eccentricity | 0.99936 |
| Orbital period | ~75,700 years |
| Inclination | 145.73° |
| 156.37° | |
| Argument of periapsis | 294.45° |
| Mean anomaly | 0.001° |
| Last perihelion | 17 October 1998 |
| TJupiter | –1.406 |
| Earth MOID | 0.410 AU |
| Jupiter MOID | 0.476 AU |
| Comet total magnitude (M1) | 7.8 |
| Comet nuclear magnitude (M2) | 14.0 |
Comet Williams, also known as C/1998 P1, is a non-periodic comet that was observed between August 1998 and April 1999. It is the only comet discovered by Australian astronomer Peter Francis Williams.