76P/West–Kohoutek–Ikemura is a Jupiter-family periodic comet in the Solar System with a current orbital period of 6.47 years. It last came to perihelion on 13 April 2026 and will next come to perihelion on 22 September 2032.
Discovery and observations The comet was initially spotted on a photographic plate by Richard M. West at the European Southern Observatory Sky Atlas Laboratory, Geneva in January 1975, when it had a brightness of magnitude 12. Inability to predict its movement from a single image meant the comet had to be presumed lost. In late February it was accidentally rediscovered by Lubos Kohoutek at the Hamburg Observatory, Germany and independently on 1 March by Toshihiko Ikemura in Shinshiro, Japan. After further observations the comet's parabolic orbit was computed, which gave a perihelion date of 23 March 1975. It was demonstrated that all three sightings were of the same object, which was accordingly designated 76P/West–Kohoutek–Ikemura. The comet has been observed at its successive returns in 1987, 1993, 2000, 2006 and 2013.
Orbit Further calculations by Brian G. Marsden determined the comet's elliptical orbit and revealed that it had passed only 0.012 AU (1.8 million km) from Jupiter on 22 March 1972. This close approach had reduced its orbital frequency from some 30 years to the current 6.48 years and its perihelion distance from 4.78 AU to 1.60 AU.
Physical characteristics Its nucleus is estimated to have an effective radius of 0.31 ± 0.01 kilometers and its rotational period is estimated to be 6.6±1.0 hours.
See also List of numbered comets
References
External links 76P/West–Kohoutek–Ikemura at the JPL Small-Body Database 76P/West-Kohoutek-Ikemura at Seiichi Yoshida's website 76P/West-Kohoutek-Ikemura at Gideon van Buitenen's website