Copyright © 1999 by Akimasa Nakamura (Kuma Kogen Astronomical Observatory, Japan)
The CCD image was taken on 1999 October 9.65 UT, using a 0.60-m f/6 Ritchey-Chretien telescope.
This comet was found during 1987 January by Jennifer Wiseman on two photographic plates exposed on 1986 December 28.29 and 28.34 by Brian Skiff at Lowell Observatory's Anderson Mesa Station. The magnitude was estimated as 14. Skiff and Wiseman were able to confirm the comet on 1987 January 19.11. The comet had faded to magnitude 14.5. On both occasions the comet appeared diffuse with a strong condensation.
The first orbit was computed and published by Brian G. Marsden on January 21. He used 6 positions obtained during the period of December 28 to January 21 and indicated the comet was moving in a short-period orbit. He determined the perihelion date as 1986 November 22.76, the perihelion distance as 1.506 AU, and the orbital period as 6.53 years. Marsden said the orbit indicated the comet passed about 0.25 AU from Jupiter during 1984. With nearly a month of observations, this orbit was little different from later orbits computed with several months of observations.
The comet was kept under observation until 1987 May 25.17 when T. Gehrels and J. V. Scotti (Steward Observatory, Arizona, USA) obtained an image of magnitude 19.4 with the 0.91-m Spacewatch telescope.
S. Nakano predicted the comet would next arrive at perihelion on 1993 June 4.39. B. Schmidt obtained three CCD images with the Multiple-Mirror Telescope on Mt. Hopkins on 1993 February 2. These revealed "suspected" weak images. Unfortunately, the images were not certain enough to establish a recovery had been made. No other successful attempts were made until James V. Scotti announced he had recovered the comet on Spacewatch images exposed on December 16. The magnitude was then 20.8 and Scotti said the coma was 13 arc seconds in diameter. In addition, the nuclear condensation had a magnitude of 22.6 and a faint tail extended 0.34 arc minute toward PA 286°. Scotti subsequently found the comet on a single CCD image obtained with Spacewatch. The positions confirmed that the faint object detected by Schmidt in February was the comet. The positions also indicated the prediction by Nakano required a correction of only -0.08 day. No additional observations were obtained during this apparition.
The comet was next predicted to pass perihelion on 2000 January 11.73. The comet was recovered by astronomers at Kitt Peak on 1999 September 13.48. The comet's total magnitude exceeded 13 during November of 1999. The final observation was also obtained at Kitt Peak on 2000 May 1.16.
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