Electronic Telegram No. 4160
Central Bureau for Astronomical Telegrams
Mailing address:  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 V1 (PANSTARRS)
     Richard Wainscoat, Robert Weryk, and Eva Lilly report the discovery of
an apparent comet in four i-band exposures taken on Nov. 2.6 UT with the
Pan-STARRS1 telescope on Haleakala in very good seeing conditions (discovery
observations tabulated below), in which the object appears to be extended
compared to adjacent background stars (FWHM approximately 1".25, vs. 0".75
for nearby stars in the field-of-view); no tail is visible in a stacked image.

     2015 UT             R.A. (2000) Decl.       Mag.
     Nov.  2.60468    7 49 28.16   +64 44 18.1   20.2
           2.61571    7 49 27.63   +64 44 22.7   20.2
           2.62673    7 49 27.07   +64 44 27.2   20.3
           2.63775    7 49 26.58   +64 44 31.5   20.3

After the object was posted on the Minor Planet Center's NEOCP and PCCP
webpages, other CCD astrometrists have also noted the object's cometary
appearance.  V-band images taken by W. H. Ryan and E. V. Ryan with the
Magdalena Ridge Observatory 2.4-m f/8.9 reflector on Nov. 4.3 UT show a
point-spread function for the comet 1.5 times that of nearby field stars;
the magnitude was measured to be 20.1.  H. Sato, Tokyo, Japan, relates that
twenty-four stacked 60-s exposures taken on Nov. 4.35 with a 0.43-m f/6.8
astrograph (+ luminance filter) near Mayhill, NM, USA, show the object to
have a slightly larger profile than those of nearby stars, with a 6" coma and
no tail; the w-band magnitude was 19.3 as measured within a circular aperture
of radius 5".7.
     The available astrometry, the following preliminary parabolic orbital
orbital elements by G. V. Williams, and an ephemeris appear on MPEC 2015-V43.

     T = 2014 Oct.  8.0564 TT         Peri. = 345.7313
                                      Node  = 263.4448  2000.0
     q = 0.285229 AU                  Incl. = 101.9955


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2015 CBAT
2015 November 5                  (CBET 4160)              Daniel W. E. Green