TA e-circular

<title>TA e-circular</title>
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THE ASTRONOMER Electronic Circular No 571   1991 October 17 19.40UT
Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise,  Basingstoke,
Hants, RG22 4PP, England. Telephone:  (0256)471074 Int:+44256471074
Telex: 9312111261 Answerback: TA G                     JANET BOXES:
GMH at UK.AC.CAM.ASTRONOMY.STARLINK or GUYH at UK.AC.SUSSEX.CLUSTER
TELECOM GOLD: 10074:MIK2885                       PRESTEL 256471074
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COMET SHOEMAKER-LEVY (1991a1)
Carolyn S. Shoemaker, Eugene M. Shoemaker, and David H. Levy report
their discovery of comet.
The following positions are available:
     1991 UT             R.A. (1950) Decl.        m1    Observer
     Oct.  6.50243    2 40 01.38   +37 43 08.2   16.5   Shoemaker
           7.45833    2 38 38.97   +37 47 07.3            "
           8.32690    2 37 22.62   +37 50 39.7            "
           9.12961    2 36 10.89   +37 53 47.2          McCrosky
           9.14110    2 36 09.83   +37 53 49.9            "
          10.06256    2 34 45.84   +37 57 17.5            "
E. M. Shoemaker, C. S. Shoemaker, and D. H. Levy (Palomar).  0.46-m
   Schmidt films.  Scanned by C. S. Shoemaker; measured by K. A.
   Lawler.  On Oct. 8, the comet appeared strongly condensed with a
   coma and a short tail in p.a. 200 deg.
R. E. McCrosky and C.-Y. Shao (Oak Ridge).  1.55-m reflector + CCD.
   Oct. 10 observation made through clouds.
Preliminary parabolic orbital elements from the above observations:
     T = 1992 July 29.619 ET          Peri. = 143.888
                                      Node  =  48.569   1950.0
     q = 0.88387 AU                   Incl. = 113.914
IAUC 5363

Ephemeris by Hurst using a program by Nick James:
m =  7.5 + 5.0 log R + 10.0 log r

  Date    R.A. (1950) Dec.     R       r     Elong  Mag.    Motion
          h  m       o  '     (AU)    (AU)     o          "/hr P.A.
1991 Oct
  16.00   2 25.14  +38 15.8   3.222   4.092  146.7  16.2    51  277
  21.00   2 16.30  +38 25.7   3.142   4.039  150.5  16.0    54  274
  26.00   2  6.87  +38 29.4   3.071   3.985  153.4  15.9    57  270
  31.00   1 57.01  +38 26.6   3.010   3.931  154.9  15.8    59  267
1991 Nov
   5.00   1 46.85  +38 16.8   2.958   3.877  154.6  15.7    61  264
  10.00   1 36.58  +38  0.1   2.917   3.823  152.5  15.6    61  261
  15.00   1 26.39  +37 36.6   2.885   3.768  149.1  15.6    61  258
  20.00   1 16.46  +37  7.1   2.863   3.713  144.6  15.5    60  255
  25.00   1  6.95  +36 32.5   2.850   3.658  139.5  15.4    59  252
  30.00   0 58.01  +35 53.8   2.846   3.602  134.1  15.3    56  249
1991 Dec
   5.00   0 49.74  +35 12.4   2.849   3.547  128.4  15.3    53  246
  10.00   0 42.21  +34 29.4   2.860   3.490  122.6  15.2    49  244

The comet could reach magnitude 7 or brighter and be well placed in
the northern sky, during 1992 July.

Guy M Hurst
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