Alcock is a comet in the Comet orbit class. Its orbit takes it from 1.54 AU to 1,476.07 AU from the Sun; one orbit takes 20,081.8 years. Orbit from the JPL solution of 15 April 2021.
Where is it now
- Distance from Sun
- 86.848 AU
- True anomaly
- 165.16°
- Distance from Earth
- 86.192 AU
- As of
- 25 October 2026
Two-body Kepler propagation — accurate to ~0.1% for major planets over decades, less so for highly-perturbed bodies. Use JPL Horizons for high precision.
In the sky
- Right ascension
- 03h 32m 42s
- Declination
- -31° 23′ 37″
- Constellation
- Fornax
- Distance from Earth
- 86.19 AU
- Elongation from the Sun
- 131.08° — well clear of the Sun
Favours the southern hemisphere; low or below the horizon from far north.
From your location
See how high it is right now, whether it is up after civil twilight, and when it rises and sets where you are.
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Two-body approximation, good to about a degree for the planets — enough to find the constellation and know whether it is up.
Orbital elements
- Semi-major axis
- 738.804 AU
- Eccentricity
- 0.9979
- Inclination
- 86.22°
- Orbital period
- 20,081.8 years
- Perihelion
- 1.537 AU
- Aphelion
- 1,476.071 AU
- Longitude of ascending node
- 43.47°
- Argument of periapsis
- 146.62°
- Epoch · J2000
- 2438164.5
- Orbit class · COM
- Comet
- Earth MOID · 246.1 LD
- 0.6323 AU
- Tisserand (Jupiter)
- 0.108
Orbit quality
- Observations used
- 25
- Data arc
- 118 days
- First observed
- 20 March 1963
- Last observed
- 16 July 1963
- Residual RMS
- 0.32 ″
- Solution · Otto Matic
- 15 April 2021
Discovery & classification
Also known as 1963 F1
Sources
- visual properties: JPL SBDB (lookup)
- visual properties: JPL SBDB (lookup)
- orbital elements: JPL SBDB