[IAUC] CBET 4021: 20141121 : COMET P/2014 W4 (PANSTARRS)

[quai en eps.harvard.edu]

                                                  Electronic Telegram No. 4021
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 en eps.harvard.edu (alternate cbat en iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network


COMET P/2014 W4 (PANSTARRS)
     R. J. Wainscoat reports the discovery of a comet in four w-band CCD
exposures taken with the 1.8-m Pan-STARRS1 telescope at Haleakala on Nov. 18
(discovery observations tabulated below); the object has a diffuse appearance
with a short tail extending for approximately 2" in p.a. 200 degrees.

     2014 UT             R.A. (2000) Decl.       Mag.
     Nov. 18.50270    3 00 11.23   +23 10 13.0   20.7
          18.51538    3 00 10.77   +23 10 12.4   20.6
          18.52805    3 00 10.31   +23 10 12.1   20.5
          18.54073    3 00 09.84   +23 10 11.7   20.7

Wainscoat and M. Micheli report that three 60-s r-band follow-up exposures,
tracked at the rate of the comet by Wainscoat and A. Draginda with the 3.6-m
Canada-France-Hawaii Telescope at Mauna Kea on Nov. 19.4 UT, show a 4" tail to
the southwest with a small coma (FWHM about 1".1 in 0".65 seeing) of magnitude
20.3-20.7.  After the object was posted on the Minor Planet Center's PCCP
webpage, other CCD astrometrists have also commented on the object's cometary
appearance.  W. H. Ryan (Magdalena Ridge Observatory 2.4-m f/8.9 reflector +
R-band filter) notes a small coma of magnitude 19.7-19.8 that is slightly
larger than nearby stars of similar brightness and a small tail toward p.a.
about 225 deg on Nov. 19.23-19.26.  H. Sato, Tokyo, Japan, writes that twelve
stacked 60-s exposures taken with an iTelescope 0.51-m f/6.8 astrograph (+
luminance filter) at Siding Spring on Nov. 19.6 shows the comet to be strongly
condensed with a faint outer coma 10" in diameter (w-band magnitude 19.5 as
measured within a circular aperture of radius 6".6) with no tail.

     The available astrometry (including pre-discovery Pan-STARRS1 observations
from Oct. 25.6 UT, with the comet reported then at mag 20.8-21.3; identified by
T. Spahr), the following preliminary elliptical orbital elements by G. V.
Williams, and an ephemeris appear on MPEC 2014-W57.

                    Epoch = 2016 Jan. 13.0 TT
     T = 2015 Dec. 26.1230 TT         Peri. =  67.7623
     e = 0.363188                     Node  =  33.1955  2000.0
     q = 4.231388 AU                  Incl. =  15.1262
       a =  6.644646 AU    n = 0.0575435    P =  17.1 years


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

                         (C) Copyright 2014 CBAT
2014 November 21                 (CBET 4021)              Daniel W. E. Green