 | |
| Discovery | |
|---|---|
| Discovered by | Tom Gehrels (Spacewatch) |
| Discovery date | September 8, 1991 |
| Designations | |
| P/1991 R2, 1990 XXIX, 1991x, P/1996 F1 | |
| Orbital characteristics | |
| Epoch | March 13, 2013 (2456364.5) [1] |
| Aphelion | 4.730779 AU |
| Perihelion | 1.52546421 AU |
| Semi-major axis | 3.12812162 AU |
| Eccentricity | 0.5123385 |
| Orbital period | 5.53 a 2020.8 d |
| Inclination | 9.98579° |
| Last perihelion | 7 March 2024 [2] 27 August 2018 [3] 16 February 2013 |
125P/Spacewatch is a periodic Jupiter-family comet. It was discovered on September 8, 1991, by Tom Gehrels using the 0.91 m Spacewatch telescope at the Kitt Peak National Observatory. [4] It was the first comet discovered with the use of a CCD [5] and also the faintest comet upon discovery up to that point. [4] It has a diameter of 1.6 km. [6]
The comet was discovered in images taken by the 0.91 m Spacewatch telescope at the Kitt Peak National Observatory by Tom Gehrels on September 8, 1991 as an essentially stellar object with an apparent magnitude of 21, with a tail more than 5 arcminutes long. [7] Brian G. Marsden calculated a parabolic and an elliptical orbit, with the elliptical orbit suggesting an orbital period of 5.58 years and a perihelion date on 18 December 1990. [8]
The comet was recovered on 21 March 1996 by the Spacewatch telescope from James V. Scotti and J. Montani, with an apparent magnitude of 17.6, a tail measuring 0.66 arcminutes long and a coma measuring 15 arcseconds across. The orbit calculated after the recovery indicates an orbital period of 5.56 years. [9] During that apparition the comet experienced an outburst in late July 1996 and brightened to a magnitude of 14.5. [4] During the 2002 apparition the comet brightened to a magnitude of 18. [4]
