Circular No. 6626

Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION

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COMET 1997 G2

J. Montani, Lunar and Planetary Laboratory, reports the discovery of another comet with the Spacewatch 0.9-m telescope at Kitt Peak. The coma subtends 7′′–8′′ on the exposures, taken in good seeing. A tail is plainly visible in the Apr. 12 CCD scans; the main tail is 25′′ long in p.a. 355^{o}, and fine streamers 20′′ and 15′′ long lie at p.a. 340^{o} and 10^{o}, respectively.

1997 UT  α_{2000}  δ_{2000}  m_{1}
Apr. 12.46169  16^{h}00^{m}25.^{s}11  −7^{o}57′17′′.7  18.4
12.47629  16 00 24.51  −7 57 20.8  18.3
12.49199  16 00 23.89  −7 57 25.2  18.4
13.32855  15 59 50.82  −8 00 31.0  18.3
13.33954  15 59 50.38  −8 00 34.4  18.4
13.35111  15 59 49.88  −8 00 37.0  18.2
13.35875  15 59 49.57  −8 00 39.5  18.5
13.36431  15 59 49.36  −8 00 40.4  18.3
13.37117  15 59 49.05  −8 00 41.8  18.2

COMET C/1997 D1 (MUELLER)

Ephemeris extension to IAUC 6563 (orbital elements MPC 29285):

1997TT α_{2000} δ_{2000} Δ r ϵ β m_{1}
Apr. 12 9^{h}33.^{m}15 +52^{o}33.^{′}7 2.663 3.033 101.^{o}9 18.^{o}9 13.4
17 9 19.05 +51 33.1 2.713 2.997  96.5 19.4 13.4
22 9 06.92 +50 25.6 2.767 2.962  91.1 19.8 13.4
27 8 56.65 +49 13.8 2.825 2.928  85.8 20.0 13.4
May 2 8 48.06 +47 59.8 2.885 2.894  80.5 20.1 13.4
7 8 40.97 +46 45.1 2.945 2.860  75.3 20.0 13.4
12 8 35.20 +45 30.8 3.005 2.827  70.2 19.6 13.4
17 8 30.57 +44 17.9 3.064 2.795  65.2 19.2 13.4
22 8 26.91 +43 06.7 3.121 2.763  60.3 18.6 13.4
27 8 24.09 +41 57.5 3.175 2.732  55.5 17.8 13.4
June 1 8 21.99 +40 50.5 3.226 2.701  50.8 16.9 13.4
6 8 20.50 +39 45.8 3.272 2.671  46.2 15.9 13.3
11 8 19.52 +38 43.3 3.314 2.642  41.6 14.8 13.3
16 8 18.98 +37 42.9 3.350 2.614  37.2 13.6 13.3
21 8 18.80 +36 44.4 3.380 2.586  32.8 12.3 13.3
1997 April 14  \begin{matrix}c \\ ◯ \end{matrix} Copyright 1997 CBAT  Daniel W. E. Green