Electronic Telegram No. 1122 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 2007oo IN UGC 12558 Further to CBET 1096, R. Mostardi and W. Li report the discovery of an apparent supernova on unfiltered KAIT images taken on Nov. 6.21 (at mag 18.9) and 7.21 UT (mag 18.8). The new object is located at R.A. = 23h22m19s.50, Decl. = +50o09'20".0 (equinox 2000.0), which is 2".7 east and 12".4 south of the nucleus of UGC 12558. KAIT images taken on 2006 Nov. 11.19 (limiting mag 20.0) and 2007 Oct. 31.23 (limiting mag 19.5) showed nothing at this location. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2007 CBAT 2007 November 7 (CBET 1122) Daniel W. E. Green