Electronic Telegram No. 2780
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 P/2010 JC81 (WISE)
     An asteroidal object discovered with the WISE satellite (reported on
MPS 326646 with a two-day arc; discovery observation tabulated below;
MPEC 2010-V52 issued on 2010 Nov. 5 when additional observations were
found in November) has been found to show cometary appearance by other CCD
astrometrists.  G. V. Borisov, Crimean Laboratory, Sternberg Astronomical
Institute, reports that 90-s unfiltered CCD images taken with the 20-cm f/1.5
astrograph at the Crimean Observatory at Nauchny on Aug. 1.01 UT show a faint
0'.2 coma of mag 14.7 and 0'.6 tail toward p.a. about 45 deg; additional
frames taken with the Crimean 60-cm Cassegrain telescope and the 2.6-m Shajn
telescope confirmed the object's cometary appearance on Aug. 2, showing a
condensed coma of diameter 20" with magnitude V = 15.1.  Observations by
Borisov on Aug. 4.0 with the 20-cm astrograph show a condensed coma of
diameter 12" has with magnitude V = 14.8.  V. Rumyantsev, Crimean
Astrophysical Observatory, writes that images taken with the 2.6-m f/4
Shajn reflector on Aug. 3.0 show a coma diameter of 20" and magnitude 15.4.
A previously unconfirmed report of diffuseness with a 10" coma (red mag
18.0-18.2) from 2010 Nov. 5 was made by L. Buzzi, P. Concari, S. Foglia,
G. Galli, and M. Tombelli from CCD images taken with a 0.18-m f/2.8
Newtonian reflector located at the Tzec Maun Observatory near Moorook,
Australia.

     2010 UT             R.A. (2000) Decl.       Observer
     May  10.62033   22 45 02.67   -52 16 29.2   WISE

Additional astrometry, the following orbital elements by G. V. Williams,
and an ephemeris appear on MPEC 2010-P24.

                    Epoch = 2011 Apr. 29.0 TT
     T = 2011 Apr. 26.5605 TT         Peri. =  12.5719
     e = 0.777598                     Node  =  30.7680  2000.0
     q = 1.810730 AU                  Incl. =  38.6900
       a =  8.141700 AU    n = 0.0424259    P =  23.23 years


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2011 CBAT
2011 August 5                    (CBET 2780)              Daniel W. E. Green