Electronic Telegram No. 1420 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 2008cg A. V. Filippenko, J. M. Silverman, R. Mostardi, and C. V. Griffith, University of California, Berkeley, report that inspection of a CCD spectrum (range 330-1000 nm), obtained on June 29 UT with the 3-m Shane reflector (+ Kast) at Lick Observatory, shows that the type-IIn supernova 2008cg (CBETs 1366, 1368) is very similar to supernovae 1997cy, 1999E, 2002ic, and 2005gj at a few months after the outbursts. It has been proposed that such objects are the result of a type-Ia supernova exploding within a dense circumstellar envelope (Hamuy et al. 2003, Nature 424, 651; Aldering et al. 2006, Ap.J. 650, 510). Further observations over a range of wavelengths are urged. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2008 CBAT 2008 June 30 (CBET 1420) Daniel W. E. Green