Circular No. 5618

Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION

Postal Address: Central Bureau for Astronomical Telegrams Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A. Telephone 617-495-7244/7440/7444 (for emergency use only) TWX 710-320-6842 ASTROGRAM CAM EASYLINK 62794505 MARSDEN@CFA or GREEN@CFA (.SPAN, .BITNET or .HARVARD.EDU)

PERIODIC COMET CIFFREO (1992s) J. V. Scotti, Lunar and Planetary Laboratory, reports his recovery of

this comet with the Spacewatch telescope at Kitt Peak. On the first night there was a coma 15′′ across and a tail 0′.36 long in p.a. 261^{o} (m_{2} = 20.6).

1992 UT  α_{2000}  δ_{2000}  m_{1}
Sept.24.27955  23^{h}47^{m}39.^{s}92  −24^{o}51′11′′.0
24.29928  23 47 38.76  −24 51 11.4
24.32086  23 47 37.49  −24 51 11.0  18.0
25.24211  23 46 46.17  −24 50 57.5  18.1
25.25011  23 46 45.68  −24 50 57.6
25.25872  23 46 45.18  −24 50 56.8

The indicated correction to the prediction on MPC 16378 (ephemeris on MPC 19888) is ΔT = +0.6 day. The following improved orbital elements, by B. G. Marsden, Center for Astrophysics, satisfy 62 observations 1985-1992 with mean residual 0′′.9:

Epoch = 1993 Jan. 13.0 TT

T = 1993 Jan. 23.0649 TT  ω = 358.^{o}0335
e = 0.543173  Ω = 53.7092 }2000.0
q = 1.708765 AU  i = 13.0894
a = 3.740509 AU n^{o} = 0.1362411 P = 7.234 years
1992/93 α_{2000}  δ_{2000}  Δ  r  ϵ  β  m_{1}
Sept. 25 23^{h}47.^{m}00 −24^{o}50.^{′}9 1.100 2.048 153.^{o}7 12.^{o}5 17.8
Oct. 5 23 38.05 −24 28.0 1.088 2.000 146.6 16.0 17.7
15 23 30.86 −23 25.0 1.095 1.954 138.1 19.9 17.6
25 23 26.60 −21 44.7 1.118 1.912 129.5 23.6 17.6
Nov. 4 23 25.93 −19 32.6 1.155 1.872 121.3 26.9 17.5
14 23 28.98 −16 55.4 1.201 1.836 113.5 29.6 17.5
24 23 35.51 −13 59.2 1.256 1.804 106.5 31.7 17.6
Dec. 4 23 45.17 −10 48.6 1.316 1.776 100.0 33.1 17.6
14 23 57.52 − 7 27.7 1.381 1.752  94.1 34.1 17.6
24 0 12.16 − 3 59.7 1.450 1.733  88.7 34.6 17.7
Jan. 3 0 28.80 − 0 27.6 1.523 1.720  83.7 34.6 17.8
13 0 47.14 + 3 05.7 1.598 1.712  79.1 34.4 17.9
23 1 06.99 + 6 37.2 1.677 1.709  74.9 33.8 17.9
Feb. 2 1 28.21 +10 04.0 1.759 1.711  70.9 33.0 18.1

1992 September 25 Daniel W. E. Green