Electronic Telegram No. 1021 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 2007gi IN NGC 4036 A. Harutyunyan, S. Benetti, E. Cappellaro, Istituto Nazionale di Astrofisica, Osservatorio Astronomico di Padova; F. Patat, European Southern Observatory; and F. Ghinassi, Telescopio Nazionale Galileo (TNG), report that a spectrum of 2007gi (cf. CBET 1017), obtained on Aug. 4.90 UT with the 3.5-m TNG (+ DOLORES; range 380-750 nm, resolution 1.8 nm), shows it to be a type-Ia supernova well before maximum. The best fit to this spectrum found by the 'PASSparToo' supernova-spectra comparison tool (Harutyunyan et al. 2005, ASP Conf. Ser. 342, 258) is with the type-Ia supernova 1999dk at 13 days before maximum, though 2007gi shows a higher expansion velocity -- i.e., 20500 km/s, as measured from the Si II 635-nm feature, and adopting 1445 km/s for the host-galaxy recession velocity (Falco et al. 1999, PASP 111, 438). Also, the S II absortions, measured at 532 and 559 nm in the galaxy rest frame, are stronger. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2007 CBAT 2007 August 4 (CBET 1021) Daniel W. E. Green