Electronic Telegram No. 1336 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 SUPERNOVA 2008bt IN NGC 3404 Independent discoveries have been reported of an apparent supernova on unfiltered CCD images: on Apr. 13.23 UT by D. Winslow, W. Li, and A. V. Filippenko, University of California at Berkeley, via LOSS/KAIT images (cf. CBET 1322); and on Apr. 14.548 by K. Itagaki, Teppo-cho, Yamagata, Japan, using a 0.60-m f/5.7 reflector (communicated by S. Nakano). Discovery data are tabulated below: 2008 UT R.A. (2000.0) Decl. Mag Offset Observer Apr. 13.23 10 50 16.88 -12 06 32.0 16.6 16".4 W, 0".4 S LOSS/KAIT Apr. 14.548 10 50 16.99 -12 06 31.5 16.6 14" W, 1".1 S Itagaki Additional magnitudes for 2008bt in NGC 3404: 2006 Feb. 23, [19.0 (Itagaki); 2008 Apr. 3.24, [18.8 (KAIT); 4.54, [18.5 (Itagaki); 14.24, 16.5 (KAIT). Itagaki adds that nothing is visible at the position of 2008bt on the Digitized Sky Survey. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2008 CBAT 2008 April 14 (CBET 1336) Daniel W. E. Green