Circular No. 6349

Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION

Postal Address: Central Bureau for Astronomical Telegrams 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) Phone 617-495-7244/7440/7444 (for emergency use only)

COMET P/1996 F1 (SPACEWATCH) J. V. Scotti, Lunar and Planetary Laboratory, reports that he and J.

Montani have recovered comet P/1991 R2 (= 1991x = 1990 XXIX) with the 0.9-m Spacewatch telescope at Kitt Peak. The nuclear magnitude m_{2} was 19.6 and 19.4 on Mar. 21.35 and 22.26 UT, respectively; on Mar. 21.35 a 0′.66 tail extended in p.a. 264^{o} from a 15′′ coma. The indicated correction to the prediction by S. Nakano on MPC 22032 (ephemeris on MPC 25984) is ΔT = −2.4 days.

1996 UT  α_{2000}  δ_{2000}  m_{1}
Mar. 21.34514  11^{h}46^{m}51.^{s}04  +10^{o}40′46′′.0
21.36731  11 46 50.06  +10 41 04.8  17.6
21.39018  11 46 49.08  +10 41 24.5
22.24455  11 46 15.44  +10 53 37.0  17.4
22.25146  11 46 15.16  +10 53 42.9  17.4
22.26075  11 46 14.75  +10 53 50.8

The following improved orbital elements, by B. G. Marsden, satisfy 36 observations 1991–1996 with mean residual 0′′.71:

Epoch = 1996 July 16.0 TT

T = 1996 July 14.5658 TT  ω = 87.^{o}2733
e = 0.509139  Ω = 153.3661 }2000.0
q = 1.539721 AU  i = 9.9666

a = 3.136773 AU n^{o} = 0.1774106 P = 5.556 years

1996 TT α_{2000}  δ_{2000}  Δ  r  ϵ  β  m_{1}
Mar. 18 11^{h}49.^{m}06 + 9^{o}52.^{′}6 0.918 1.907 171.^{o}0 4.^{o}7 17.6
28 11 42.47 +12 13.6 0.884 1.856 161.0 10.1 17.4
Apr. 7 11 36.78 +14 15.8 0.871 1.807 149.6 16.3 17.3
17 11 33.39 +15 46.0 0.877 1.761 138.8 22.0 17.2
27 11 33.38 +16 36.7 0.896 1.718 129.0 27.1 17.1
May 7 11 37.24 +16 46.7 0.925 1.678 120.4 31.3 17.1
17 11 44.95 +16 18.5 0.960 1.643 112.9 34.6 17.1
27 11 56.25 +15 15.8 0.999 1.612 106.4 37.1 17.1
June 6 12 10.68 +13 42.9 1.041 1.586 100.9 38.9 17.1
16 12 27.77 +11 44.1 1.085 1.565  96.3 40.2 17.1
26 12 47.11 + 9 23.3 1.131 1.551  92.3 40.9 17.2
July 6 13 08.31 + 6 45.4 1.180 1.542  88.9 41.2 17.2
16 13 31.07 + 3 54.9 1.232 1.540  85.9 41.2 17.3
1996 March 22  \begin{matrix}c \\ ◯ \end{matrix} Copyright 1996 CBAT  Brian G. Marsden