This was probably Comet West, which was seen in 1976. For more information, visit Gary Kronks Comet Pages.
Brian Marsden at the IAU Minor Planet Center, revised the orbit for this comet using 28 positions obtained between 1975 August 10 and 1976 January 27.
Comet West had an elliptical orbit with a perihelion date of February 25.22, a perihelion distance of 0.197 AU, and an orbital period of about 254,000 years.
E. Everhart (University of Denver, Colorado) took this orbit, applied perturbations by all nine planets, and ran the comet backwards to a point prior to its entry into the solar system and concluded the comet was not fresh from the Oort comet cloud.
Copyright 1997 Dr. Sten Odenwald
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