Circular No. 6695

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)

              URL http://cfa-www.harvard.edu/cfa/ps/cbat.html

Phone 617-495-7244/7440/7444 (for emergency use only)

COMET P/1997 M2 (MUELLER 2) S. Nakano, Sumoto, Japan, reports that A. Sugie and A. Nakamura

have independently recovered comet P/1990 R1 (= 1990j = 1990 XXIV) as shown below. The indicated correction to the prediction by K. Muraoka on MPC 23484 (ephemeris on MPC 29676) is ΔT = −0.26 day.

1997 UT α_{2000} δ_{2000} m_{1} Observer
June 29.75005 0^{h}46^{m}50.^{s}91 +10^{o}37′10′′.7 18.9 Sugie
29.75421 0 46 51.18 +10 37 12.3  _{”}
29.75838 0 46 51.47 +10 37 12.7  _{”}
July 5.76997 0 53 51.20 +11 20 13.4 19.9 Nakamura
5.77361 0 53 51.40 +11 20 14.6  _{”}
5.78924 0 53 52.43 +11 20 21.2  _{”}

A. Sugie (Dynic Astronomical Observatory). 0.60-m f/4.0 reflector + CCD. A. Nakamura (Kuma Kogen). 0.60-m f/6.0 Ritchey-Chrétien + CCD.

Weakly condensed coma of diameter 15′′. Possible faint tail in p.a. 260^{o}.

Improved orbital elements by Nakano from 59 observations 1990–1997: Epoch = 1997 Nov. 8.0 TT

T = 1997 Nov. 22.1998 TT  ω = 179.^{o}6386
e = 0.343905  Ω = 214.2850 }2000.0
q = 2.412127 AU  i = 7.3554

a = 3.676490 AU n^{o} = 0.1398151 P = 7.049 years

1997 TT α_{2000}  δ_{2000}  Δ  r  ϵ  β  m_{1}
July 1 0^{h}48.^{m}33 +10^{o}46.^{′}4 2.483 2.582 84.^{o}0 23.^{o}1 19.1
11 0 59.65 +11 55.2 2.342 2.560  90.5 23.4 18.9
21 1 09.86 +12 55.0 2.203 2.540  97.3 23.4 18.8
31 1 18.73 +13 44.0 2.068 2.521 104.5 22.9 18.6
Aug. 10 1 25.96 +14 20.4 1.938 2.504 112.2 22.0 18.4
20 1 31.26 +14 42.1 1.817 2.487 120.4 20.5 18.3
30 1 34.37 +14 47.1 1.706 2.473 129.3 18.4 18.1
Sept. 9 1 35.08 +14 33.7 1.610 2.459 138.9 15.6 17.9
19 1 33.42 +14 00.9 1.530 2.448 149.1 12.2 17.8
29 1 29.65 +13 09.6 1.472 2.438 160.0  8.1 17.7
Oct. 9 1 24.35 +12 02.9 1.437 2.429 171.3  3.6 17.6
19 1 18.44 +10 47.2 1.428 2.422 175.8  1.7 17.6
29 1 12.92 + 9 30.4 1.445 2.417 164.7  6.2 17.6
1997 July 6  \begin{matrix}c \\ ◯ \end{matrix} Copyright 1997 CBAT  Brian G. Marsden