20D/Westphal
| Discovery | |
|---|---|
| Discovered by | J. G. Westphal |
| Discovery date | July 24, 1852 |
| Alternative 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 yr |
| Inclination | 40.890° |
| Last perihelion | January 3, 1976[1] (unobserved) |
| Next perihelion | May 4, 2038[1] (lost since 1913) |
20D/Westphal was a periodic comet with an orbital period of 61 years. It fits the classical definition of a Halley-type comet with (20 years < period < 200 years).[2] It was 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 (La Plata Astronomical Observatory) and then others. It was predicted to return in 1976[1] but was never observed, and is now considered a lost comet.
References[]
- ^ a b c Seiichi Yoshida (2004-02-21). "20D/Westphal". Seiichi Yoshida's Comet Catalog. Retrieved 2012-02-20.
- ^ "JPL Small-Body Database Browser: 20D/Westphal" (1913-10-13 last obs). Jet Propulsion Laboratory. Retrieved 2012-07-26.
External links[]
- Orbital simulation from JPL (Java) / Horizons Ephemeris
- 20D/Westphal, Comet Orbit Home Page
- 20D at Kronk's Cometography
- Orbital elements, Infrared Processing and Analysis Center
- 20D/Westphal – Minor Planet Center
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Categories:
- Cometary object articles
- Periodic comets
- Halley-type comets
- Numbered comets
- Near-Earth comets
- Lost comets
- Astronomical objects discovered in 1852
- Comet stubs