Electronic Telegram No. 82 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 2004em IN IC 1303 M. Armstrong, Rolvenden, Kent, England, reports his discovery of an apparent supernova of mag 17.5 on unfiltered CCD images taken on Sept. 14.968 and 15.831 UT with a 0.35-m reflector. SN 2004em is located at R.A. = 19h31m31s.11, Decl. =+35o52'15".7 (equinox 2000.0), which is approximately 10".4 east and 20".3 south of the center of IC 1303. Nothing was visible at this position on his image taken on July 28 (limiting mag 19.0) or on a red Palomar Sky Survey image from 1992.664 (limiting mag 20.8) and a blue image from 1988.449 (limiting mag 22.5). NOTE: These 'Central Bureau Electronic Telegrams' are intended to be preliminary announcements of items that later appear in the formal IAU Circulars. Citations should normally be made to IAUCs rather than to CBETs. (C) Copyright 2004 CBAT 2004 September 16 (CBET 82) Brian G. Marsden