Circular No. 6288

Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION

Postal Address: Central Bureau for Astronomical Telegrams Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A. IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)

BMARSDEN@CFA.HARVARD.EDU or DGREEN@CFA.HARVARD.EDU (science) Phone 617-495-7244/7440/7444 (for emergency use only)

COMET C/1996 A1 (JEDICKE)

The following precise CCD positions have been reported:

1996 UT α_{2000} δ_{2000} m_{1} Observer
Jan. 16.01936 9^{h}23^{m}33.^{s}77 +7^{o}09′48′′.5  Pravec
16.03166 9 23 33.43 +7 09 48.8  _{”}
16.03755 9 23 33.29 +7 09 49.1 17.0  _{”}
16.04809 9 23 33.02 +7 09 49.8 16.0 Tichá
16.05170 9 23 32.89 +7 09 49.9  _{”}
16.05418 9 23 32.84 +7 09 50.1  _{”}
16.19571 9 23 29.36 +7 09 55.6 16.7 Offutt
16.24265 9 23 28.14 +7 09 57.4  _{”}
16.29265 9 23 26.80 +7 09 59.0  _{”}

P. Pravec and L. Šarounová (Ondřejov). 0.65-m f/3.6 reflector. J. Tichá, M. Tichý and Z. Moravec (Kleť). 0.57-m f/5.2 reflector. W. Offutt (Cloudcroft). 0.60-m f/7 Ritchey-Chrétien. Tail > 2′ long.

Further to the observations on IAUC 6287, J. V. Scotti, Lunar and Planetary Laboratory, notes that on Jan. 15.28 there was a tail 4′.74 long in p.a. 293^{o}; the comet’s nuclear magnitude was 20.3.

The following parabolic orbital elements, from 15 observations Jan. 14–16, are extremely uncertain:

T = 1997 Apr. 17.758 TT  ω = 324.^{o}878
Ω = 264.410 }2000.0
q = 2.46872 AU  i = 8.109
1996TT α_{2000}  δ_{2000}  Δ  r  ϵ  β  m_{1}
Jan. 13 9^{h}24.^{m}81 + 7^{o}08.^{′}3 4.338 5.213 149.^{o}9 5.^{o}4 16.9
18 9 22.70 + 7 11.1 4.264 5.174 155.3 4.6 16.8
23 9 20.38 + 7 15.5 4.197 5.136 160.5 3.7 16.7
28 9 17.87 + 7 21.3 4.138 5.097 165.5 2.8 16.7
Feb. 2 9 15.24 + 7 28.4 4.086 5.058 169.7 2.0 16.6
7 9 12.51 + 7 36.7 4.041 5.019 171.8 1.6 16.5
12 9 09.74 + 7 46.1 4.005 4.981 170.4 1.9 16.5
17 9 06.97 + 7 56.2 3.976 4.942 166.4 2.7 16.4
22 9 04.26 + 8 06.9 3.955 4.903 161.5 3.7 16.4
27 9 01.67 + 8 17.9 3.942 4.865 156.3 4.7 16.3
1996 January 16  \begin{matrix}c \\ ◯ \end{matrix} Copyright 1996 CBAT  Brian G. Marsden