Circular No. 5729

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)

COMET MUELLER (1993d) J. V. Scotti, Lunar and Planetary Laboratory, provides the following

precise positions, obtained with the 0.9-m Spacewatch telescope, Kitt Peak:

1993 UT  α_{2000}  δ_{2000}  m_{1}
Mar. 26.46322  12^{h}56^{m}39.^{s}87  +64^{o}22′17′′.0  18.2
26.49987  12 56 38.28  +64 22 16.8
26.50309  12 56 38.08  +64 22 16.9
28.17852  12 55 25.11  +64 21 20.3
28.18181  12 55 24.90  +64 21 20.0
28.18539  12 55 24.83  +64 21 19.7
28.37872  12 55 16.00  +64 21 11.6  16.6
28.38299  12 55 15.82  +64 21 11.6

Nuclear magnitudes m_{2} = 21.5 on Mar. 26 and 19.8 on Mar. 28. Cirrus was probably present on Mar. 26, and the magnitudes may be too faint; the coma was of diameter 12′′, and the tail extended > 0′.75 in p.a. 298^{o}. On Mar. 28 the coma diameter was 18′′, and the tail extended 3′.17 in p.a. 300^{o}.

Parabolic orbital elements from 10 observations Mar. 19-28:

T = 1993 June 15.991 TT  ω = 93.^{o}265
Ω = 74.894 }2000.0
q = 6.10432 AU  i = 53.757
1993 TT α_{2000}  δ_{2000}  Δ  r  ϵ  β  m_{1}
Feb. 22 13^{h}15.^{m}18 +63^{o}11.^{′}3 5.618 6.156 118.^{o}8 8.^{o}1 17.1
Mar. 4 13 11.09 +63 49.4 5.619 6.147 118.0 8.2 17.1
14 13 05.34 +64 14.0 5.634 6.139 116.2 8.4 17.1
24 12 58.47 +64 22.8 5.663 6.132 113.7 8.6 17.1
Apr. 3 12 51.13 +64 14.2 5.704 6.126 110.5 8.8 17.2
13 12 44.04 +63 47.9 5.756 6.121 106.8 9.0 17.2
23 12 37.81 +63 04.9 5.817 6.116 102.6 9.2 17.2
May 3 12 32.93 +62 06.4 5.885 6.112  98.3 9.4 17.2
13 12 29.66 +60 54.8 5.960 6.109  93.7 9.5 17.2
23 12 28.09 +59 32.3 6.038 6.107  89.1 9.5 17.3
June 2 12 28.21 +58 01.2 6.120 6.105  84.4 9.5 17.3

1993 March 28 Brian G. Marsden