A series of photographs were obtained by T. Gehrels and R. Adams (Palomar Observatory, California, USA) using the 122-cm Schmidt telescope during the end of October 1975, as part of Gehrels' survey for unusual solar system objects. As he examined these plates during the first week of November, he found a trail on an exposure obtained on 27 October. He described the object as nearly stellar, but slightly diffuse, with a nuclear magnitude of 17. The object was subsequently found on plates exposed with the same telescope on 28 and 30 October.The comet was recovered on 7 August 1984 by J. Gibson (Palomar Observatory, California, USA). He was using the 122-cm Schmidt (the same telescope that originally discovered the comet) and gave the nuclear magnitude as 20. Close approaches to planets:•0.0014 AU from Jupiter on 1970 August 15 (decreased perihelion distance from 5.64 AU to 3.42 AU and decreased orbital period from 17.16 to 8.11 years)•0.0755 AU from Jupiter on 2063 May 21 (will decrease perihelion distance from 3.50 AU to 3.16 AU and decrease orbital period from 8.27 to 8.19 years)Date10x10 magErrorKphot magComa '