Electronic Telegram No. 266 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://cfa-www.harvard.edu/iau/cbat.html SUPERNOVA 2005hj Further to IAUC 8622, R. Quimby, P. Hoeflich, and S. J. Kannappan, University of Texas, report the discovery of a supernova in unfiltered CCD images taken on Oct. 26.13 UT (at mag about 17.3) using the 0.45-m ROTSE-IIIb telescope at the McDonald Observatory. SN 2005hj is located at R.A. = 1h26m48s.27, Decl. = -1o14'16".8 (equinox 2000.0; uncertainty +/- 0".7), which is 2".8 west and 0".5 north of the center of the apparent host galaxy. The new object was found by subtracting a co-addition of images taken between Aug. 22 and 27 (limiting mag about 18.7). A spectrogram (range 420-890 nm), obtained on Oct. 26.30 with the 9.2-m Hobby-Eberly Telescope (+ Marcario Low-Resolution Spectrograph) by S. C. Odewahn and E. Terrazas, shows 2005hj to be a type-Ia supernova; assuming that narrow lines at 694, 514, and 710 nm are H-alpha, H-beta, and S II, respectively, a redshift of z = 0.058 is implied for the apparent host. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2005 CBAT 2005 October 26 (CBET 266) Daniel W. E. Green