Electronic Telegram No. 2084 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A. IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions) CBAT@CFA.HARVARD.EDU (science) URL http://www.cfa.harvard.edu/iau/cbat.html COMET C/2009 Y1 (CATALINA) An apparently asteroidal object reported by R. E. Hill (discovery observation below) using the 0.68-m Schmidt at the Catalina Sky Survey and added to the NEO Confirmation Page was shown to be cometary by W. H. Ryan and E. V. Ryan at the Magdalena Ridge Observatory, when observations on Dec. 18.4 and 20.5 UT with the 2.4-m f/8.9 reflector showed a faint tail in p.a. 260 deg. Hints of cometary activity on the western side of the nucleus were also suspected by H. Sato (RAS Observatory, Mayhill, 0.25-m f/3.4 reflector) on Dec. 18.4 and by L. Buzzi (Schiaparelli Observatory, 0.60-m f/4.64 reflector) on Dec. 20.2. 2009 UT R.A. (2000) Decl. Mag. Observer Dec. 17.51495 12 10 29.85 +44 28 31.3 19.4 Hill Further astrometry, the following parabolic orbital elements and an ephemeris are given on MPEC 2009-Y33. T = 2011 Jan. 25.403 TT Peri. = 128.725 Node = 160.385 2000.0 q = 2.44938 AU Incl. = 107.503 NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2009 CBAT 2009 December 20 (CBET 2084) Brian G. Marsden