Electronic Telegram No. 4103
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
CBAT Director:  Daniel W. E. Green; Hoffman Lab 209; Harvard University;
 20 Oxford St.; Cambridge, MA  02138; U.S.A.
e-mail:  cbatiau@eps.harvard.edu (alternate cbat@iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network


COMET C/2015 K2 (PANSTARRS)
     [Editorial note:  The cometary designation 2015 K1 has been given
to another comet that was planned for announcement first, but political
issues are preventing announcement prior to this comet.]
     E. Lilly, Institute for Astronomy, University of Hawaii, reports the
discovery of another apparent comet in four w-band exposures taken with the
1.8-m Pan-STARRS1 telescope at Haleakala on May 18 UT (discovery observations
tabulated below); the object shows a soft appearance, but there is no visible
tail present on any of the images.

     2015 UT             R.A. (2000) Decl.       Mag.
     May  18.33481   13 00 28.53   - 7 51 31.2   21.8
          18.34789   13 00 29.97   - 7 50 50.6   21.5
          18.36096   13 00 31.40   - 7 50 09.9   21.7
          18.37411   13 00 32.85   - 7 49 29.1   21.7

R. Wainscoat and M. Micheli obtained three 120-s follow-up exposures of the
comet using the 3.6-m Canada-France-Hawaii Telescope at Mauna Kea on May 20.2
UT (queue observer P. Forshay); the object displays a faint tail about 3"
long extending toward p.a. 110 deg from the nuclear condensation; the red
magnitude was given as 21.5-21.8.  After the object was posted on the Minor
Planet Center's PCCP webpage, H. Sato (Tokyo, Japan) obtained forty stacked
20-s images with an iTelescope 0.70-m f/6.6 astrograph (+ luminance filter)
at Siding Spring that show a moderately condensed coma 8" in diameter with
no tail; the w-band magnitude was 20.1 as measured within a circular aperture
of radius 4".4.
     The available astrometry, the following preliminary parabolic orbital
elements by G. V. Williams, and an ephemeris appear on MPEC 2015-K56.

     T = 2015 June  8.8034 TT         Peri. =  15.7750
                                      Node  = 223.6857  2000.0
     q = 1.456616 AU                  Incl. =  29.1748


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2015 CBAT
2015 May 23                      (CBET 4103)              Daniel W. E. Green