| Discovery | |
|---|---|
| Discovered by: | J. G. Westphal |
| Discovery date: | July 24, 1852 |
| Alternate designations: | 21P/1852 O1; 1852 IV; 21P/1913 S1; 1913 VI; 1913d |
| Orbital characteristics A | |
| Epoch: | 1913-11-09 (JD 2420080.5) |
| Aphelion: | 30.030 AU |
| Perihelion: | 1.2540 AU |
| Semi-major axis: | 15.642 AU |
| Eccentricity: | 0.9198 |
| Orbital period: | 61.87 a |
| Inclination: | 40.890° |
| Last perihelion: | January 3, 1976 (unobserved) |
| Next perihelion: | May 4, 2038 (lost) |
20D/Westphal is a periodic comet in our solar system, originally discovered by the German astronomer J. G. Westphal (Göttingen, Germany) on July 24, 1852.
It was independently discovered by the American astronomer Christian Heinrich Friedrich Peters (Constantinople) on August 9.
The comet was last seen between September 27 and November 26, 1913, first by Pablo T. Delavan (La Plata Astronomical Observatory) and then others. It was predicted to return in 1976 but was never observed, and is now considered a lost comet.
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|---|---|---|
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