Circular No. 8318

Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION

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COMET C/2004 G1 (LINEAR) H. Love, Lincoln Laboratory, MIT, reports the LINEAR discovery of

a comet with a very diffuse coma and a diffuse tail roughly in p.a. 270^{o}. Available CCD observations:

2004 UT α_{2000} δ_{2000} Mag. Observer
Apr. 9.36391 18^{h}26^{m}14.^{s}09 +72^{o}12′45′′.3 18.5 LINEAR
9.37507 18 26 18.41 +72 13 46.7 18.5  _{”}
9.38657 18 26 23.27 +72 14 47.6 18.9  _{”}
9.39817 18 26 28.00 +72 15 52.1 18.6  _{”}
9.40920 18 26 32.08 +72 16 52.1 18.7  _{”}
10.20872 18 32 11.74 +73 27 51.7 17.7 Hutsebaut
10.21066 18 32 12.81 +73 28 02.0 17.9  _{”}
10.44329 18 33 58.40 +73 48 36.6 17.8 Young
10.44479 18 33 59.09 +73 48 44.8  _{”}
10.44676 18 33 59.98 +73 48 55.3  _{”}
10.45289 18 34 02.86 +73 49 28.2  _{”}
10.46123 18 34 06.62 +73 50 11.4  _{”}
10.46725 18 34 09.46 +73 50 43.2  _{”}

LINEAR (Socorro, NM). 1.0-m f/2.15 reflector. R. Hutsebaut (Mt. Joy, NM). 0.30-m reflector. J. Young (Table Mountain). 0.6-m reflector. Coma diameter 5′′, with

central condensation; faint tail extends nearly 30′′ in p.a. 245^{o}; ‘haze’ extending 10′′ behind the head in p.a. 230^{o}-300^{o}.

Preliminary parabolic orbital elements from the above observations (ephemeris magnitudes from H = 16.0, n = 3):

T = 2004 June 5.643 TT  ω = 111.^{o}748
Ω = 228.676 }2000.0
q = 1.19210 AU  i = 114.628
2004TT α_{2000}  δ_{2000}  Δ  r  ϵ  β Mag.
Apr. 10 18^{h}30.^{m}6 +73^{o}09.^{′}4 1.167 1.479 85.^{o}6 42.^{o}5 17.6
15 19 27.4 +80 01.0 1.203 1.436 80.6 43.6 17.6
20 22 12.8 +84 35.4 1.254 1.395 75.4 44.2 17.6
25 2 13.3 +83 15.4 1.317 1.357 70.0 44.2 17.6
30 3 44.0 +78 56.6 1.388 1.322 64.8 43.6 17.6
May 5 4 19.8 +74 33.3 1.464 1.291 59.6 42.4 17.7
2004 April 10  \begin{matrix}c \\ ◯ \end{matrix} Copyright 2004 CBAT  Daniel W. E. Green