Electronic Telegram No. 3260 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/2012 T7 (VOROBJOV) Tomas Vorobjov, Bratislava, Slovak Republic, reports his discovery of a comet on three 120-s images that he took remotely with Alexander Kostin (Houston, TX, U.S.A.) using a 0.81-m f/7 Ritchey-Chretien reflector located at the Mt. Lemmon SkyCenter via the Sierra Stars Observatory Network (discovery observations tabulated below) in the course of a minor-planet search survey undertaken as part of the International Astronomical Search Collaboration (IASC) school campaigns. Vorobjov asked R. Holmes (Ashmore, IL, USA) to obtain follow-up observations the following night, and twenty-four stacked images taken by Holmes (0.61-m f/4 astrograph; measured by Vorobjov and S. Foglia) on Oct. 16.4 UT revealed a 6" coma and a tail 25" long in p.a. 260 deg. After posting on the Minor Planet Center's NEOCP webpage, other CCD astrometrists have also commented on the object's cometary appearance. Four stacked 180-s images taken in good seeing by P. Miller, P. Roche, A. Tripp, R. Miles, R. Holmes, S. Foglia, and L. Buzzi on Oct. 16.6 (measured by Buzzi, Foglia, and T. Vorobjov) with the 2.0-m f/10 "Faulkes Telescope South" at Siding Spring shows a 5" compact coma elongated east-west, with a tail at least 15" long in p.a. 265 deg. L. Buzzi (Varese, Italy; 0.60-m f/4.6 reflector; Oct. 17.0) writes that stacked images totalling 15 minutes of exposure time in good seeing (but with passing high clouds) show a compact coma 5" wide with a thin tail 14" long in p.a. 265 deg. R. Williams (Sierra Stars Observatory, Markleeville, CA, U.S.A.; 0.61-m f/10 Cassegrain reflector; Oct. 17.4) writes that twenty stacked 180-s images reveal a tail at least 30" long in p.a. 265 degrees and a coma of size 4" x 8" elongated in the direction of the tail. H. Sato (Tokyo, Japan; remotely using a 0.51-m f/6.8 astrograph at the RAS Observatory near Mayhill, NM, U.S.A.; Oct. 17.45) finds a diffuse coma of diameter 15". Images obtained by G. Masi and F. Nocentini (Ceccano, Italy; 0.36-m f/8.7 reflector; measured by G. Masi and U. Masi; Oct. 17.9) show a fuzzy object about 6" in size. A. Boattini (Mount Lemmon 1.5-m reflector; Oct. 17.4) writes that four co-added 40-s exposures show a very condensed and asymmetric coma (3" by 5") of mag 19.1-19.5 with a very narrow tail about 28-30" long. Three stacked 120-s R-band images taken remotely by E. Guido, N. Howes, and G. Sostero with the 2.0-m f/10 "Faulkes Telescope North" at Haleakala on Oct. 18.43 under good seeing conditions shows a narrow tail nearly 15" long in p.a. 270 deg with a coma of size 6" x 4" elongated in the same direction. Erik Bryssinck (Kruibeke, Belgium; seven stacked, unfiltered, 180-s images taken remotely using a 0.43-m f/6.8 astrograph located at the RAS Observatory near Mayhill, part of the iTelescope network; Oct. 18.3) finds a diffuse coma about 17" in diameter with a hint of a tail 23" long to the northwest in p.a. 316 deg; he adds that astrometry was difficult due the lack of a central condensation. 2012 UT R.A. (2000) Decl. Mag. Observer Oct. 15.36615 3 31 20.58 +14 55 51.9 20.1 Vorobjov 15.38666 3 31 20.14 +14 55 46.2 20.4 " 15.40791 3 31 19.67 +14 55 40.4 20.1 " The available astrometry, the following preliminary elliptical orbital elements by Gareth V. Williams, and an ephemeris appear on MPEC 2012-U40. T = 2012 June 16.5841 TT Peri. = 174.7685 e = 0.336050 Node = 213.3434 2000.0 q = 3.785996 AU Incl. = 13.5543 a = 5.702233 AU n = 0.0723830 P = 13.62 years NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2012 CBAT 2012 October 18 (CBET 3260) Daniel W. E. Green