Electronic Telegram No. 3368
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/2013 A1 (SIDING SPRING)
     R. H. McNaught reported the discovery of an apparently asteroidal object
on CCD images obtained with the 0.5-m Uppsala Schmidt telescope on Jan. 3
(discovery observations tabulated below); after posting at the Minor Planet
Center's NEOCP webpage, McNaught reported that five stacked follow-up 40-s
images taken on Jan. 4.5 UT in good seeing showed a slightly diffuse object
with a strongly condensed 10" coma of total mag 18.3-18.4 -- noting that, on
the discovery night, the seeing was poor and there was a collimation problem
that was fixed in the intervening 24 hours.  H. Sato (Tokyo, Japan; remotely
using a 0.51-m f/6.8 astrograph at the iTelescope Observatory, Siding Spring;
Jan. 4.4-4.6) reports a 10" round coma with a hint of tail northwards in his
stacked images.

     2013 UT             R.A. (2000) Decl.       Mag.   Observer
     Jan.  3.53978    5 12 10.63   -21 29 57.1   18.6   McNaught
           3.55185    5 12 10.10   -21 29 57.1   18.6     "
           3.56300    5 12 09.58   -21 29 57.1   18.4     "

The available astrometry (including prediscovery observations on 2012
Dec. 8 from the Catalina Sky Survey), the following nearly-parabolic
orbital elements by G. V. Williams, and an ephemeris appear on MPEC
2013-A14.

     T = 2014 Oct. 25.08285 TT        Peri. =   2.54133
     e = 0.9995246                    Node  = 300.85326 2000.0
     q = 1.3921432 AU                 Incl. = 128.96230


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2013 CBAT
2013 January 5                   (CBET 3368)              Daniel W. E. Green