Circular No. 6949

Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION

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COMET C/1998 M2 (LINEAR)

CCD astrometry is reported of another comet discovered by LINEAR:

1998 UT α_{2000} δ_{2000} m_{1} Observer
May 28.40143 18^{h}35^{m}29.^{s}98 −5^{o}18′22′′.6 17.0 Blythe
28.43816 18 35 27.95 −5 17 26.0 17.6  _{”}
June 19.25996 18 12 55.00 +3 51 56.2 16.9 Shelly
19.27829 18 12 53.62 +3 52 17.0  _{”}
19.94265 18 12 06.81 +4 08 16.1 16.0 Tichý
19.94534 18 12 06.67 +4 08 20.1  _{”}
20.20518 18 11 48.39 +4 14 33.2 15.2 Offutt
20.22171 18 11 47.19 +4 14 57.9 16.0  _{”}
20.27988 18 11 43.01 +4 16 19.6  Balam
20.28751 18 11 42.47 +4 16 30.6  _{”}
20.52118 18 11 26.07 +4 22 05.0 14.6 Abe
20.52951 18 11 25.46 +4 22 17.8  _{”}
20.53547 18 11 25.03 +4 22 26.0 14.5 Sugie
20.53895 18 11 24.78 +4 22 31.1  _{”}

M. Blythe, F. Shelly and M. Bezpalko (Socorro). 1-m f/2.15 reflector. Measurers J. Stuart, H. Viggh and R. Sayer. May 28 observations are prediscovery. On June 19 there was a tail ∼ 200′′ long in p.a. ∼ 210^{o}.

M. Tichý (Kleť). 0.57-m f/5.2 reflector. W. Offutt (Cloudcroft). 0.6-m f/7 reflector. Tail ∼ 1′ in p.a. 200^{o}. D. Balam (Dominion Astrophysical Observatory). 1.8-m reflector. H. Abe (Yatsuka). 0.26-m f/6.0 reflector. Communicated by S. Nakano. A. Sugie (Dynic). 0.6-m f/5 reflector. 0′.6 coma; 4′ tail in p.a. 190^{o}.

Parabolic orbital elements from 13 observations May 28–June 20:

T = 1998 Aug. 10.3901 TT  ω = 36.^{o}3601
Ω = 260.8857 }2000.0
q = 2.733431 AU  i = 60.2039
1998TT α_{2000} δ_{2000} Δ r ϵ β m_{1}
June 21 18^{h}10.^{m}87 + 4^{o}33.^{′}5 1.846 2.783 151.^{o}8 9.^{o}9 14.8
26 18 04.94 + 6 28.8 1.847 2.774 150.0 10.6 14.8
July 1 17 59.05 + 8 16.9 1.856 2.766 147.1 11.5 14.8
6 17 53.33 + 9 56.6 1.874 2.758 143.5 12.7 14.8
11 17 47.91 +11 27.2 1.899 2.752 139.5 13.9 14.8
16 17 42.89 +12 48.4 1.930 2.746 135.2 15.1 14.8
1998 June 20  \begin{matrix}c \\ ◯ \end{matrix} Copyright 1998 CBAT  Brian G. Marsden