Occultations of Space Telescope Guide Stars by 2060 Chiron: 1990-1995

D.J. Mink: Harvard-Smithsonian Center for Astrophysics
S.A. Stern: U. Colorado/LASP

The minor planet 2060 Chiron appears to exhibit an extended atmosphere or coma. Stellar occultations can be used to probe the region around Chiron as they have the atmospheres of the planets. A search of the Space Telescope Guide Star Catalog was conducted along the projected path of 2060 Chiron from 1 January 1990 to 31 December 1995. and 69 stars were found within 5 arcseconds of Chiron's path, after those less than 45 degrees from the sun at the time of Chiron's closest approach were eliminated.

Stars which Chiron approaches within 1 arcsecond include GSC 776.0612 (V=13.4) on 16 February 1991, GSC 800.0307 (V=14.69) on 9 January 1992, GSC 241.0175 (V=10.45) on 6 January 1993, and GSC 4930.0473 (V=13.87) on 13 February 1995. Further refinement of the ephemeris of 2060 Chiron is needed to improve the accuracy of these predictions.

This work was redone with an improved Chiron ephemeris furnished by Larry Wasserman of Lowell Obseravtory, and 46 stars were found within 5 arcseconds of Chiron's path.

Abstract published in the Bulletin of the A.A.S., Volume 22, page 1358.