Circular No. 5159 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION Postal Address: Central Bureau for Astronomical Telegrams Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A. Telephone 617-495-7244/7440/7444 (for emergency use only) TWX 710-320-6842 ASTROGRAM CAM EASYLINK 62794505 MARSDEN or GREEN@CFA.BITNET MARSDEN or GREEN@CFAPS2.SPAN COMET BREWINGTON (1991a) The following observations have been reported: 1991 UT R.A. (1950) Decl. m1 Observer Jan. 7.476 0 07.0 - 6 15 9 Kiuchi 7.48 0 07.3 - 6 10 9.5 Camilleri 7.531 0 07.4 - 6 10 9 Bradfield T. Kiuchi (Usuda, Nagano, Japan). 25x150 binoculars. Independent discovery. Communicated by H. Kosai. P. Camilleri (Cobram, Victoria). 20x80 binoculars. Communicated by R. H. McNaught. W. A. Bradfield (near Adelaide, S. Australia). Independent discovery. Communicated by A. C. Beresford. Total visual magnitude estimate by D. H. Levy, Tucson, AZ (0.41-m reflector): Jan. 8.12 UT, 8.7. (2060) CHIRON K. J. Meech, University of Hawaii, writes: "CCD observations made on 1990 Dec. 16 and 17 with the University of Hawaii 2.2-m telescope on Mauna Kea indicate that the coma of Chiron is more extensive than has been seen before. A composite 540-s exposure through the R filter shows an extended coma/tail at p.a. about 293 deg. This closely agrees with the anti-solar direction, 292.3 deg, at the time of the observation. The coma extends out to at least 2 x 10E5 km and is visible in exposures as short as 90 s. The absolute magnitude, H = 6.2, is significantly brighter than observations obtained during 1990 September with the same system. April and September observations showed that Chiron was continuing the trend of decreasing brightness seen since 1989 January. The December observations (r = 10.65 AU) suggest another possible outburst." KR AURIGAE Visual magnitude estimates (cf. IAUC 4682) by A. Boattini, Florence, Italy: 1989 Mar. 4.93 UT, 13.3; Sept. 30.99, 14.0; Oct. 23.90, 13.3; 1990 Feb. 23.79, 13.0; Apr. 16.81, 13.4; Nov. 17.05, 13.8. 1991 January 8 (5159) Daniel W. E. Green
Our Web policy. Index to the CBAT/MPC/ICQ pages.