[IAUC] CBET 3189: 20120723 : COMET P/2012 O2 (McNAUGHT)

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                                                  Electronic Telegram No. 3189
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/2012 O2 (McNAUGHT)
     R. H. McNaught, Australian National University, reports his discovery of
a comet on CCD images obtained with the 0.5-m Uppsala Schmidt telescope at
Siding Spring (discovery astrometry tabulated below); five stacked 60-s
follow-up exposures by McNaught on July 20.7 UT, tracked on the comet's
motion, show a "near-asteroidal condensation" with a faint 0'.2 tail long in
p.a. 260 deg.  After posting on the Minor Planet Center's NEOCP webpage,
other CCD astrometrists have commented on the object's cometary appearance.
Eighteen stacked 60-s images taken by R. Holmes (Ashmore, IL, USA; 0.61-m f/4
astrograph; measured by T. Vorobjov, L. Buzzi, and S. Foglia) during July
21.34-21.35 reveal a coma 8" wide and a hint of a tail about 10" long in p.a.
250 degrees.  E. Guido, Castellammare di Stabia, Italy, writes that thirteen
stacked 10-s R-band images taken by N. Howes, G. Sostero, and himself
remotely on July 23.5 with the 2.0-m f/10 "Faulkes Telescope North" at
Haleakala show the object to appear "soft" compared to the nearby field
stars of similar brightness (stellar FWHM = 1".0) and elongated toward p.a.
260 deg.

     2012 UT             R.A. (2000) Decl.       Mag.   Observer
     July 20.60070   23 16 53.08   -21 06 02.2   18.3   McNaught
          20.61212   23 16 53.97   -21 06 22.3   18.7     "
          20.62355   23 16 54.71   -21 06 40.8   18.7     "
          20.63499   23 16 55.53   -21 07 00.6   18.7     "
          20.71211   23 17 00.95   -21 09 11.6   18.4     "
          20.71716   23 17 01.27   -21 09 20.7   18.6     "
          20.82735   23 17 09.10   -21 12 26.4            "

The available astrometry (including previously unpublished prediscovery Mount
Lemmon observations acquired by A. Gibbs on May 20), the following elliptical
orbital elements by G. V. Williams, and an ephemeris appear on MPEC 2012-O27.

                    Epoch = 2012 July 12.0 TT
     T = 2012 June 25.09813 TT        Peri. = 183.04681
     e = 0.5384617                    Node  = 120.81501 2000.0
     q = 1.6609099 AU                 Incl. =  24.52909
       a =  3.5986392 AU   n = 0.14437654   P =   6.83 years


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2012 CBAT
2012 July 23                     (CBET 3189)              Daniel W. E. Green