G A R Y   W.   K R O N K ' S   C O M E T O G R A P H Y


Past, Present, and Future Orbits by Kazuo Kinoshita

Giovanni Sostero photo of 92P/Sanguin exposed on 2002 September 29
Copyright © 2002 by Giovanni Sostero (Italy)

This image was obtained by Giovanni Sostero on 2002 September 29.85. It is composed of twenty 30-second exposures obtained with a 0.3-m f/2.8 Baker Schmidt, and a Hi-Sis 24 CCD camera.


     J. G. Sanguin (El Leoncito) discovered this comet with the 51-cm double astrograph on 1977 October 15.06. He gave the total magnitude as 16. The comet was confirmed by Hans-Emil Schuster (European Southern Observatory) on October 20 with the 100-cm Schmidt telescope. Schuster estimated the magnitude as 15-16 and said the object was diffuse with some condensation. In moonlight, there was also a very faint tail to the northeast. An independent discovery was made by C. Torres (Cerro El Roble, Chile) on plates exposed on October 11.08. He was unable to confirm the object until October 19. Torres gave the magnitude as 13-14 on the 11th and described the comet as diffuse, with a condensation. There was a tail extending 20" northeastward. On the 19th, Torres said the comet was magnitude 16 and was diffuse, without a condensation. At the beginning of November, J. Gibson (Palomar Observatory, California, USA) found a prediscovery image on an exposure made by S. J. Bus and T. Lauer on September 13.27. The total magnitude was given as 14.5.

Historical Highlights

  • The first orbit was calculated by Brian G. Marsden using positions spanning the period of October 11 to 20. Although a parabolic orbit with a perihelion date of 1977 October 4.45 was given, he said an elliptical orbit was more probable and gave a perihelion date of 1977 September 23.57 and a period of 14.13 years. Following the announcement of the September 13 position, Marsden said the elliptical orbit was confirmed. The resulting perihelion date was September 17.69 and the period was 12.61 years.
  • cometography.com