Electronic Telegram No. 3256
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 C/2012 T4 (McNAUGHT)
     R. H. McNaught reports his discovery of a comet (discovery observations
tabulated below) on images taken with the 0.5-m Uppsala Schmidt telescope at
Siding Spring, noting a moderately condensed 0'.2 coma of total mag 17.5 and a
0'.3 tail toward the northeast; his follow-up images on Oct. 15.4-15.6 UT
show the object as more diffuse, but he notes that the seeing was poorer than
on the discovery night.  After posting on the Minor Planet Center's NEOCP
webpage, other CCD astrometrists have also commented on the object's cometary
appearance.  Ten co-added 30-s images taken by T. Linder, R. Holmes, and R.
Sampson with a 0.41-m f/11 Ritchey-Chretien telescope at Cerro Tololo on Oct.
15.0 show a round coma 5" in diameter.  H. Sato (Tokyo, Japan; remotely using
a 0.51-m f/6.8 astrograph at the RAS Observatory near Mayhill, NM, U.S.A.)
found a moderately condensed coma of diameter 10" on images taken on Oct. 15.1.

     2012 UT             R.A. (2000) Decl.       Mag.   Observer
     Oct. 13.42762   19 20 33.81   -39 45 32.5   17.8   McNaught
          13.43820   19 20 35.38   -39 45 33.9   17.5     "
          13.44883   19 20 36.94   -39 45 33.6   17.9     "
          13.45944   19 20 38.69   -39 45 35.7   17.5     "
          13.52658   19 20 48.93   -39 45 40.2   17.5     "
          13.52970   19 20 49.37   -39 45 40.5   17.3     "

The available astrometry, the following preliminary parabolic orbital
elements by G. V. Williams, and an ephemeris appear on MPEC 2012-U5.

     T = 2012 Oct. 10.3863 TT         Peri. = 219.6306
                                      Node  =  99.3012  2000.0
     q = 1.960445 AU                  Incl. =  24.1074


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2012 CBAT
2012 October 16                  (CBET 3256)              Daniel W. E. Green