Circular No. 7057

Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION

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COMET C/1998 W2 (HERGENROTHER)

A comet was found by C. W. Hergenrother on CCD images obtained by T. B. Spahr on Nov. 22 in the course of the Catalina Sky Survey. The following observations are available, including their prediscovery data:

1998 UT α_{2000} δ_{2000} m_{1} Observer
Nov. 21.09564 21^{h}15^{m}03.^{s}67 −14^{o}37′45′′.0 17.3 Spahr
21.11709 21 15 06.83 −14 37 05.8  _{”}
22.11424 21 17 28.64 −14 07 22.7  _{”}
22.12267 21 17 29.82 −14 07 07.6  _{”}
22.13156 21 17 30.79 −14 06 50.1 17.5  _{”}
23.12154 21 19 51.86 −13 37 15.8  Larson
23.12350 21 19 52.10 −13 37 12.4  _{”}
23.12544 21 19 52.38 −13 37 09.1  _{”}
23.12934 21 19 52.95 −13 37 01.7  _{”}
23.43594 21 20 36.78 −13 27 52.5  Nakamura
23.44010 21 20 37.35 −13 27 44.8 17.7  _{”}
23.44427 21 20 37.99 −13 27 37.4  _{”}

T. B. Spahr and C. W. Hergenrother (Catalina 0.41-m f/3 Schmidt). Faint

images, moderately strong condensation, broad 30′′–60′′ tail in p.a. 80^{o}. S. M. Larson (Catalina 1.5-m refl.). Measurers Spahr and Hergenrother. A. Nakamura (Kuma Kogen). 0.6-m f/5.8 Ritchey-Chrétien. Coma 17′′,

tail 35′′ in p.a. 71^{o}. Communicated by S. Nakano.

A parabolic orbit follows. The comet is probably of short period.

T = 1998 Nov. 26.131 TT  ω = 6.^{o}512
Ω = 352.280 }2000.0
q = 1.56059 AU  i = 23.364
1998/99 α_{2000}  δ_{2000}  Δ  r  ϵ  β  m_{1}
Nov. 23 21^{h}19.^{m}58 −13^{o}40.^{′}9 1.441 1.561 77.^{o}5 38.^{o}1 17.2
28 21 31.52 −11 11.4 1.471 1.561 76.0 37.8 17.3
Dec. 3 21 43.58 − 8 42.2 1.503 1.563 74.6 37.4 17.3
8 21 55.74 − 6 13.7 1.537 1.569 73.3 37.0 17.4
13 22 07.97 − 3 46.5 1.574 1.578 72.0 36.4 17.5
18 22 20.28 − 1 21.0 1.614 1.589 70.8 35.8 17.6
23 22 32.65 + 1 02.2 1.656 1.604 69.5 35.1 17.6
28 22 45.08 + 3 22.6 1.701 1.621 68.4 34.3 17.8
Jan. 2 22 57.55 + 5 40.0 1.749 1.640 67.2 33.5 17.9
1998 November 23  \begin{matrix}c \\ ◯ \end{matrix} Copyright 1998 CBAT  Brian G. Marsden