TA e-circular

<title>TA e-circular</title>
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THE ASTRONOMER Electronic Circular No 724       1993 Apr 03 16.08UT
Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise,  Basingstoke,
Hants, RG22 4PP,England. Telephone/FAX(0256)471074 Int:+44256471074
TELEX: 9312111261 Answerback: TA G      TELECOM GOLD: 10074:MIK2885
GMH at UK.AC.RUTHERFORD.STARLINK.ASTROPHYSICS  STARLINK: RLSAC::GMH
GMH at UK.AC.CAM.ASTRONOMY.STARLINK            STARLINK: CAVAD::GMH
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COMET SHOEMAKER-LEVY (1993)
The following parabolic orbital elements satisfy the nine
observations and indicate minimum approach to Jupiter 0.31 AU on
1993 Mar. 30:
     T = 1994 Aug. 3.441 TT           Peri. = 300.459
				      Node  = 344.563   2000.0
     q = 2.36996 AU                   Incl. =   2.322

     The following representative elliptical orbital elements give
the minimum approach to Jupiter as 0.04 AU on 1992 July 28:

     T = 1988 Dec. 5.767 TT           Peri. =  43.253
     e = 0.18714                      Node  = 347.657   2000.0
     q = 3.91756 AU                   Incl. =   2.684

This ellipse puts the comet at r = 5.4 AU around Jupiter encounter
with Jupiter-free values of q = 5.8 and 5.2 AU in 1979 and 1998,
respectively.  The ends of the Mar. 27 Oak Ridge train can be
satisfied by varying the place in orbit by +/- 0.007 day at Jupiter
encounter. Considering only its distance, the comet would have been
as bright at its Feb. 1992 opposition as it is now, but splitting
presumably occurred near Jupiter (as with P/Brooks 2 in 1886), and
this is presumably to be associated with brightening.
IAUC 5726

The following ephemeris by the Editor, using EPH.EXE by N.James
is based on the parabolic elements above:
  Date    R.A. (2000) Dec.     R       r     Elong  Mag.    Motion
	  h  m       o  '     (AU)    (AU)     o          "/hr P.A.
1993 Apr
   3.00  12 21.87   -3 35.0   4.436   5.430  173.0  13.6    20  292
   8.00  12 19.39   -3 19.9   4.409   5.390  167.5  13.5    20  292
  13.00  12 16.96   -3  5.1   4.389   5.351  161.9  13.5    19  292
  18.00  12 14.63   -2 50.8   4.377   5.312  156.4  13.5    18  292
  23.00  12 12.42   -2 37.1   4.371   5.273  150.9  13.4    17  293
  28.00  12 10.40   -2 24.5   4.372   5.233  145.5  13.4    16  293
1993 May
   3.00  12  8.57   -2 13.1   4.380   5.194  140.2  13.4    14  293
   8.00  12  6.98   -2  3.0   4.392   5.155  134.9  13.3    12  293
  13.00  12  5.65   -1 54.6   4.410   5.115  129.7  13.3    10  293
  18.00  12  4.59   -1 47.8   4.433   5.076  124.6  13.3     7  293
  23.00  12  3.82   -1 42.9   4.459   5.036  119.6  13.3     5  293
  28.00  12  3.35   -1 39.9   4.489   4.997  114.6  13.2     3  294

COMET MUELLER (1993d)

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

     T = 1993 June 15.991 TT          Peri. =  93.265
				      Node  =  74.894   2000.0
     q = 6.10432 AU                   Incl. =  53.757
IAUC 5729

The comet is presently of m1=17 and fading.

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