Circular No. 6784

Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION

Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.

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COMET P/1997 X2 (KOWAL-VÁVROVÁ) J. V. Scotti reports his recovery of comet P/1983 J3 (= 1983t = 1983

III) = 1983 JG with the Spacewatch telescope at Kitt Peak. No information about the comet’s appearance was given for Dec. 5; on Dec. 6, the comet was stellar (m_{2} = 22.3).

1997 UT  α_{2000}  δ_{2000}  m_{1}
Dec. 5.48725  10^{h}26^{m}08.^{s}29  +5^{o}23′55′′.5  21.8
5.49825  10 26 08.57  +5 23 53.6  20.8
5.50948  10 26 08.97  +5 23 50.7  21.6
6.48070  10 26 36.39  +5 20 25.1
6.50146  10 26 36.93  +5 20 19.3
6.52285  10 26 37.50  +5 20 16.5

The indicated correction to the prediction by S. Nakano on MPC 25184 (ephemeris on MPC 30481) is ΔT ∼ +5.3 days. The following improved orbital elements by G. V. Williams, Smithsonian Astrophysical Observatory, are from 14 observations, 1983–1997 (mean residual 0′′.8):

Epoch = 1998 Nov. 3.0 TT

T = 1998 Nov. 19.0548 TT  ω = 18.^{o}7359
e = 0.587156  Ω = 202.2878 }2000.0
q = 2.575587 AU  i = 4.3454

a = 6.238637 AU n^{o} = 0.0632513 P = 15.582 years

1997 /98 α_{2000}  δ_{2000}  Δ  r  ϵ  β  m_{2}
Dec. 8 10^{h}27.^{m}30 + 5^{o}15.^{′}2 3.412 3.701 99.^{o}3 15.^{o}2 22.3
18 10 31.05 + 4 45.0 3.220 3.652 108.4 14.8 22.2
28 10 33.28 + 4 23.5 3.037 3.604 117.9 14.0 22.0
Jan. 7 10 33.85 + 4 12.4 2.866 3.555 127.9 12.6 21.8
17 10 32.68 + 4 12.7 2.711 3.507 138.2 10.8 21.6
27 10 29.81 + 4 24.9 2.577 3.459 149.0  8.4 21.3
Feb. 6 10 25.40 + 4 48.8 2.468 3.412 160.1  5.6 21.1
16 10 19.84 + 5 22.7 2.386 3.365 171.0  2.6 20.8
26 10 13.66 + 6 03.8 2.333 3.319 173.9  1.8 20.7
Mar. 8 10 07.53 + 6 48.1 2.309 3.273 163.6  4.9 20.8
18 10 02.16 + 7 31.4 2.313 3.228 152.4  8.2 20.9
28 9 58.13 + 8 09.7 2.342 3.184 141.5 11.3 21.1
Apr. 7 9 55.90 + 8 40.0 2.392 3.141 131.0 13.9 21.2
1997 December 10  \begin{matrix}c \\ ◯ \end{matrix} Copyright 1997 CBAT  Daniel W. E. Green