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THE ASTRONOMER Electronic Circular No 1310      1998 Jun 07 20.09UT
Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise,  Basingstoke,
Hants, RG22 4PP,England.Telephone/FAX(01256)471074Int:+441256471074
INTERNET: GUY@TAHQ.DEMON.CO.UK             GMH at AST.STAR.RL.AC.UK
WORLD WIDE WEB                    http://www.demon.co.uk/astronomer
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COMET C/1998 K5 (LINEAR)
It appears that yet another comet has been recognized among the
fast-moving objects reported by the Lincoln Laboratory Near-Earth
Asteroid Research project and included on The NEO Confirmation
Page:

     1998 UT             R.A. (2000) Decl.        m2
     May  26.37939   17 26 02.33   + 2 02 11.1   18.0

The high orbital eccentricity indicated in the early computations
was the first clue that the object might be a comet, although there
were the complications that the orbit has a low inclination and
that, when asked, several observers felt that their data showed the
object to be asteroidal in nature.  The first observational
indication of cometary character was provided by P. J. Shelus, who
remarked that images obtained by J. G. Ries (McDonald, 0.76-m
reflector, poor seeing) on May 29.39 UT seemed to show a tail to
the south and west, roughly opposite the object's direction of
motion.  P. Pravec (Ondrejov, 0.65-m reflector) also remarked on
the tail, consistently on coadded images and marginally on
individual images, 0'.4 long in p.a. 235 deg on May 27.03,
0'.4 long in p.a. 225 deg on May 28.95 and 0'.3 long in p.a. 227
deg on May 29.97.  On May 30.46 C. Veillet (Canada-France-Hawaii,
3.6-m reflector) noted a clear 30" tail on a 1-min exposure
(http://www.cfht.hawaii.edu/~veillet/A65.html).  S. Nakano reports
that A. Sugie (Dynic, 0.6-m reflector, bad seeing), observing on
May 27.58, independently noted (on four coadded frames) a 16" tail
in p.a. 230 deg.

The following parabolic orbital elements, computed by Brian
Marsden are from 128 observations May 26-30

     T = 1998 July 17.326 TT          Peri. =  99.215
                                      Node  = 211.333   2000.0
     q = 0.96411 AU                   Incl. =  10.044


1998 TT     R. A. (2000) Decl.     Delta      r    Elong Phase  m1
May  31    17 41.26    + 7 32.6    0.283    1.258  145.9  26.9 15.3
June  2    17 49.25    +10 21.5    0.266    1.237  143.2  29.4 15.0
      4    17 58.33    +13 27.8    0.250    1.217  140.1  32.3 14.8
      6    18 08.72    +16 52.4    0.236    1.197  136.6  35.6 14.6
      8    18 20.68    +20 35.1    0.223    1.178  132.7  39.3 14.5
     10    18 34.53    +24 34.4    0.212    1.159  128.4  43.4 14.3
     12    18 50.64    +28 47.2    0.203    1.141  123.7  47.8 14.1
     14    19 09.40    +33 07.6    0.196    1.123  118.7  52.5 14.0
     16    19 31.22    +37 27.4    0.191    1.106  113.5  57.4 13.8
IAUC 6923

Guy M Hurst