[IAUC] CBET 3851: 20140410 : COMET C/2013 PE_67 (CATALINA-SPACEWATCH)

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                                                  Electronic Telegram No. 3851
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 C/2013 PE_67 (CATALINA-SPACEWATCH)
     [Editor's note:  this text replaces that on CBET 3850 (designation
prefix).]
     An apparently asteroidal object found nearly simultaneously last August 9
via the Catalina Sky Survey (observers E. J. Christensen and J. A. Johnson)
and with the Spacewatch II reflector at Kitt Peak (observer J. V. Scotti) has
been found to show cometary activity in the past month by CCD astrometrists
elsewhere.  The discovery observations (first published on MPEC 2013-Q15,
where it was given the minor planet designation 2013 PE_67) are tabulated
below.

     2013 UT             R.A. (2000) Decl.       Mag.   Observer
     Aug.  9.27137   22 03 33.08   - 6 56 22.0   19.5   Christensen
           9.27795   22 03 31.39   - 6 56 17.7   19.3     "
           9.28469   22 03 29.70   - 6 56 12.5   19.6     "
           9.29142   22 03 28.00   - 6 56 08.1   19.8     "
           9.37462   22 03 06.76   - 6 55 12.1   19.6     "
           9.38108   22 03 05.07   - 6 55 07.6   19.4     "
           9.38757   22 03 03.42   - 6 55 03.3   19.4     "
           9.39405   22 03 01.72   - 6 54 58.6   19.0     "
           9.45431   22 02 46.35   - 6 54 17.3   20.3     "
           9.45998   22 02 44.95   - 6 54 14.6   19.6     "
           9.46168   22 02 44.52   - 6 54 12.8   19.3   Scotti
           9.46284   22 02 44.22   - 6 54 12.1   19.2     "
           9.46399   22 02 43.93   - 6 54 11.3   19.1     "
           9.46563   22 02 43.47   - 6 54 10.1   19.1   Christensen

H. Sato, Tokyo, Japan, was the first to report a diffuse appearance to the
Central Bureau, on stacked luminance-filter images obtained on 2014 Mar. 9.2
(0.32-m f/8 astrograph at the iTelescope Observatory near Nerpio, Spain) and
Mar. 10.5 UT (0.43-m f/6.8 astrograph at the iTelescope Observatory near
Mayhill, NM, USA); the first night he reported a moderately condensed coma
10" in diameter with no tail and magnitude 18.3 as measured within a circular
aperture of radius 5".8, while on the second night he an apparent outer coma
30" in diameter of mag 18.0 as measured within a circular aperture of radius
15".3 and a possible faint tail 3' long toward p.a. 200 degrees.  Luca Buzzi,
Varese, Italy, stacked images obtained with a 0.60-m f/4.6 reflector on
Mar. 10.15-10.18 that revealed a diffuse object with a central condensation
surrounded by a coma around 14" in size, possibly elongated to the west;
Buzzi's follow-up images on Mar. 29.1 show a central condensation surrounded
by a coma around 18" in size, the coma having a less-defined shape toward the
southeast.  William H. Ryan reports that R-band images taken on Mar. 11.34-
11.37 with the Magdalena Ridge Observatory 2.4-m f/8.9 reflector show a
distinct coma > 8" in size, elongated toward p.a. about 200 deg; Ryan's
follow-up images on Apr. 9.3 again show a distinct coma extended toward p.a.
about 140 deg.  Christensen obtained further images with the Catalina 0.68-m
Schmidt on Apr. 8.44-8.46 UT, noting that four stacked 30-s images show a
weakly condensed coma with a faint 25" tail toward p.a. 150 deg, with mag
18.7-19.1.  S. Foglia writes that eighty stacked 60-s images obtained with
a 0.61-m f/4.5 astrograph by R. Holmes (Ashmore, IL, USA) on Apr. 9.4 show
a round coma 8" in diameter and a wide tail 15" long in p.a. 160 deg.  R.
Ligustri (Talmassons, Udine, Italy) stacked fifteen 60-s images taken on
Apr. 9.4 with an iTelescope 0.50-m f/4.5 reflector, finding a coma of size
about 24".  Stacked images taken the Konkoly Observatory 0.60-m Schmidt
telescope at Piszkesteto, Hungary, on Apr. 9.80 by K. Sarneczky and I. Papp
show a 10" coma and two tails -- a 20"-long diffuse tail in p.a. about 120
deg and a 20"-long thin tail in p.a. about 180 deg.

The available astrometry (including pre-discovery Pan-STARRS1 astrometry from
2013 Aug. 3.5 and 8.5), the following orbital elements by G. V. Williams, and
an ephemeris appear on MPEC 2014-G64.

                    Epoch = 2013 Dec. 14.0 TT
     T = 2013 Dec.  9.30121 TT        Peri. =  59.48416
     e = 0.9667932                    Node  = 325.96144 2000.0
     q = 1.8470730 AU                 Incl. = 116.71780


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

                         (C) Copyright 2014 CBAT
2014 April 10                    (CBET 3851)              Daniel W. E. Green