Circular No. 8463 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION Mailstop 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://cfa-www.harvard.edu/iau/cbat.html ISSN 0081-0304 Phone 617-495-7440/7244/7444 (for emergency use only) COMET C/2005 A1 (LINEAR) R. Kracke reports the LINEAR discovery of a comet (discovery observation below). After posting on the `NEO Confirmation Page', other observers have confirmed the cometary nature on CCD images, including C. Jacques and E. Pimentel (Belo Horizonte, Brazil; 0.30-m reflector, Jan. 14.3 UT; coma diameter about 15" and a noticeable 75"-long tail in p.a. 313 deg) and J. Young (Table Mountain 0.6-m reflector, Jan. 14.5, moderate cirrus clouds; slightly elongated 12" coma of mag 15.0 and a 1'-long broad tail in p.a. 295 deg). 2005 UT R.A. (2000) Decl. Mag. Jan. 13.48135 13 51 08.43 -17 22 57.6 15.4 The available astrometry, the following preliminary parabolic orbital elements, and an ephemeris appear on MPEC 2005-A56. T = 2005 Apr. 10.933 TT Peri. = 261.840 Node = 356.082 2000.0 q = 1.07894 AU Incl. = 69.490 SUPERNOVA 2005C T. Boles, Coddenham, England, reports the discovery of an apparent supernova (mag 18.4) on unfiltered CCD images taken on Jan. 11.051 and 13.036 UT. The new object is located at R.A. = 11h15m29s.42, Decl. = +60o45'05".5 (equinox 2000.0), which is approximately 3".0 west and 10".7 north of the center of its apparent host galaxy. SN 2005C is not present on Boles' images from 2004 Apr. 21 and Nov. 20 (limiting mag 19.5) or on Digitized Sky Survey plates from 1993 (limiting red mag 21.0) or 1994 (limiting blue mag 21.5). SUPERNOVA 2004gy Further to IAUC 8461, M. Modjaz, R. Kirshner, and P. Challis report that a spectrogram of SN 2004gy (cf. IAUC 8460), obtained at Mt. Hopkins by W. Brown on Jan. 10.49 UT, reveals it to be a type-II supernova, probably within a few weeks past explosion. The spectrum consists of a blue continuum and Balmer-line P-Cyg features, with an emission-dominated H_alpha component. The host- galaxy redshift, measured from narrow H_alpha emission lines in the nucleus, is 0.0269; adopting this redshift, the expansion velocity derived from the minimum of the H_beta line is about 10000 km/s. (C) Copyright 2005 CBAT 2005 January 14 (8463) Daniel W. E. Green