Copyright © 1998 by Akimasa Nakamura (Kuma Kogen Astronomical Observatory, Japan)
This is the 1998 recovery image. The CCD image was taken on 1998 January 29.48, using a 0.60-m f/6 Ritchey-Chretien telescope. Three images were overlapped by Nakamura to produce this image, thus, ever star is tripled.
This was the first of two comets discovered at the Purple Mountain Observatory in Nanking, China during early January of 1965. It was first found on a photograph obtained on 1965 January 1. The comet was then in Gemini and the total magnitude was given as 15. The announcement was delayed for several weeks, and the first observation outside of China did not occur until February 9th when Philip Veron (Palomar Observatory, California, USA) photographed the comet.
The first orbit was computed by Leland Cunningham. He found that the three available Chinese positions were somewhat discordant; however, by taking two of the positions and combining them with the Palomar observation a short-period orbit was indicated. Shortly after the comet's final observation on April 24, the Purple Mountain Observatory announced they had computed an elliptical orbit indicating a period of 7.22 years. G. Sitarski revised the elliptical orbit toward the end of 1965 by using all positions obtained from January 1 until April 24. The resulting orbital period was 6.62 years. Sitarski also noted the comet had passed 0.145 AU from Jupiter on 1960 December 12. Previous to this encounter, the comet's period was 7.15 years.
Sitarski prepared a prediction for the comet's 1971 return which indicated a perihelion date of 1971 September 18. On 1971 December 20 Elizabeth Roemer and L. M. Vaughn recovered the comet. The resulting precise position indicated Sitarski's prediction required a correction of -1.53 days. Roemer and Vaughn determined the comet's nuclear magnitude as 20.3. With the comet three months passed perihelion, it faded after the recovery. When last seen on 1972 March 10 the nucleus had faded to magnitude 21.4.
The comet next returned to perihelion on 1978 May 7, 1985 January 2, and 1991 August 30. It last reached perihelion on 1998 April 19.05 and reached a maximum brightness of magnitude 12.5.