Electronic Telegram No. 1959 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 2009jg J. M. Silverman, I. K. W. Kleiser, C. V. Griffith, and A. V. Filippenko, University of California, Berkeley, report that inspection of a CCD spectrum (range 340-1000 nm), obtained on Sept. 26 UT with the 3-m Shane reflector (+ Kast) at Lick Observatory, shows that 2009jg (CBET 1956) is a type-Ia supernova. Cross-correlation with a library of supernova spectra using the "SuperNova IDentification" code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024) indicates that 2009jg was then within one day of maximum light. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2009 CBAT 2009 October 4 (CBET 1959) Daniel W. E. Green