Circular No. 4029 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION Postal Address: Central Bureau for Astronomical Telegrams Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A. TWX 710-320-6842 ASTROGRAM CAM Telephone 617-495-7244/7440/7444 PERIODIC COMET HALLEY (1982i) Low-resolution spectra (~ 1.5 nm) of P/Halley were obtained by 2 groups in Arizona using the Kitt Peak 4-m telescope with the cryogenic camera (spectral range = 460-800 nm; observers M. Belton, H. Spinrad, P. Wehinger, S. Wyckoff) and the Mount Hopkins 4.5-m MMT with an intensified reticon (range 300-750 nm; observers Wyckoff, Wehinger, Belton, M. Wagner, D. Schleicher). The Kitt Peak group observed on 1984 Feb. 4 UT (V = 23.5, exposure time 3600 s), Oct. 30 (V = 21.3, 5800 s), and Nov. 26 (V = 20.5, 3600 s), while the MMT group observed on 1984 Nov. 26 (V = 20.5, 4000 s). The data show no detected molecular or atomic emission features, but only a reflected solar continuum. The Nov. 26 Kitt Peak spectra probably indicate an albedo increase by ~ 30 percent over the range 460-800 nm relative to earlier spectra. The Oct. 30 data (obtained with a long slit) show a resolved/extended coma ~ 16" in diameter (5.5 x 10**4 km) in the sunward direction. 1983 TB AND COMET SHOEMAKER (1984s) Belton, Spinrad, Wehinger, and Wyckoff also report that observations made on 1984 Dec. 27 UT, with the Kitt Peak 4-m reflector and cryogenic camera (TI 800x800-pixel CCD; spectral resolution 1.5 nm), show continuous spectra for both 1983 TB and comet 1984s, except the latter did show weak [O I] 630-nm emission which extended 4"-5" into the coma. The long-slit spectra (4') of the comet also show broad wings (50") in the continuum which are significantly redder than the central part of the coma. The color of 1983 TB is like an S-type asteroid. Visual magnitude estimates for 1983 TB: 1984 Dec. 23.14 UT, 13.5: (C. Morris, Whitaker Peak, CA); 24.23, 13.5 (A. Hale, Pine Valley, CA). Total visual magnitude estimates of comet 1984s: Dec. 19.88, 10.0 (P. Valisa, Varese, Italy, 0.20-m reflector; photographic tail 10' to west); 23.19, 10.7 (C. S. Morris, 0.25-m reflector, Whitaker Peak, CA); 1985 Jan. 16.24, 10.3 (Morris, 3' tail in p.a. 40 ). COMET SHOEMAKER (1984f) Total visual magnitude estimates by C. Morris, 0.25-m reflector, near Mt. Wilson, CA: Jan. 18.56 UT, 13.0; 20.55, 13.0. 1985 January 28 (4029) Daniel W. E. Green
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