Circular No. 6979

Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION

Mailstop 18, 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)

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COMET P/1998 O1 (SHOEMAKER-LEVY 7) J. V. Scotti, Lunar and Planetary Laboratory, reports his recovery of

comet P/1991 V2 (= 1991 d_{1} = 1991 XIX) with the Spacewatch telescope on Kitt Peak. The coma was of diameter 6′′. On July 25.46, m_{2} = 22.5, and a tail extended 0′.5 in p.a. 264^{o}. On July 26.46, m_{2} = 22.1, and there was a faint tail extending 0′.15 in p.a. 275^{o}. The indicated correction to the prediction by B. G. Marsden on MPC 25183 (ephemeris on MPC 31835) is ΔT = −0.7 day.

1998 UT  α_{2000}  δ_{2000}  m_{1}
July 25.42696  3^{h}44^{m}14.^{s}39  +28^{o}47′29′′.5  20.7
25.44572  3 44 17.61  +28 47 42.9  20.4
25.46292  3 44 20.63  +28 47 54.6
26.45868  3 47 14.10  +28 59 13.6
26.46336  3 47 14.88  +28 59 16.5  20.3
26.46762  3 47 15.71  +28 59 19.5  20.1

Improved orbital elements from 32 observations 1991–1998:

Epoch = 1998 Aug. 15.0 TT

T = 1998 Aug. 24.5726 TT  ω = 95.^{o}5287
e = 0.531116  Ω = 309.5159 }2000.0
q = 1.697219 AU  i = 10.0889

a = 3.619696 AU n^{o} = 0.1431185 P = 6.887 years

1998 TT α_{2000}  δ_{2000}  Δ  r  ϵ  β  m_{1}
July 26 3^{h}45.^{m}90 +28^{o}54.^{′}1 1.935 1.721 62.^{o}5 31.^{o}6 20.0
Aug. 5 4 15.23 +30 37.4 1.859 1.708  65.4 32.7 19.8
15 4 44.90 +31 59.1 1.788 1.700  68.4 33.6 19.7
25 5 14.47 +32 57.9 1.719 1.697  71.6 34.4 19.6
Sept. 4 5 43.39 +33 33.9 1.653 1.700  75.1 35.0 19.5
14 6 11.14 +33 48.4 1.589 1.709  78.8 35.3 19.5
24 6 37.12 +33 44.2 1.526 1.722  83.1 35.3 19.5
Oct. 4 7 00.81 +33 24.8 1.464 1.741  87.8 35.0 19.4
14 7 21.72 +32 54.6 1.403 1.764  93.1 34.4 19.4
24 7 39.36 +32 18.1 1.343 1.792  99.1 33.2 19.4
Nov. 3 7 53.29 +31 39.5 1.284 1.825 105.8 31.5 19.5
13 8 03.10 +31 02.2 1.229 1.860 113.5 29.2 19.5
23 8 08.39 +30 28.6 1.180 1.900 122.2 26.1 19.5
Dec. 3 8 08.95 +29 58.7 1.139 1.942 131.9 22.2 19.6
1998 July 27  \begin{matrix}c \\ ◯ \end{matrix} Copyright 1998 CBAT  Brian G. Marsden