Electronic Telegram No. 1189 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 2007ux R. Chornock, X. Wang, and A. V. Filippenko, University of California, Berkeley, report that inspection of CCD spectra (range 330-1050 nm) obtained on 2007 Dec. 31.4 UT using the Kast spectrograph on the Shane 3-m telescope at Lick Observatory, reveals that 2007ux (CBET 1187) is a supernova of type Ia, with a spectral-feature age of about 4 days before maximum light. The apparent host galaxy lacks redshift information, but the nearby galaxy UGC 5477 (2' away) has a catalogued recession velocity of 9212 km/s (Tonry and Davis 1981, Ap.J. 246, 666); if this value is assumed to also apply to the true host galaxy, then the apparent expansion velocity of the Si II 635.5-nm feature is -10000 km/s, suggesting that the host galaxy is at a similar or higher redshift than UGC 5477. The Si II 597.2-nm absorption is unusually strong, relative to Si II 635.5-nm absorption, suggesting that the object may be somewhat subluminous, though obvious Ti II lines are not present. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2007 CBAT 2007 December 31 (CBET 1189) Daniel W. E. Green