Electronic Telegram No. 451 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://cfa-www.harvard.edu/iau/cbat.html SUPERNOVA 2006bc IN NGC 2397 S. Immler, Goddard Space Flight Center, NASA, and Universities Space Research Association; and P. J. Brown, Pennsylvania State University, on behalf of the Swift-satellite team, report on Swift Ultraviolet/Optical Telescope (UVOT) observations of SN 2006bc (cf. CBET 446, IAUC 8693) obtained on Mar. 27.93 UT. A new object is detected at R.A. = 7h21m16s.50, Decl. = -68o59'57".3 (equinox 2000.0) as compared to Digitized Sky Survey images, consistent with the position reported by Martin on CBET 446, with UVOT magnitudes B = 17.6, U = 16.7, UVW1 [181-321 nm] = 17.4, and UVW2 [112-264 nm] = 18.0. Statistical and systematic errors are 0.1 mag each. Comparing the U-B color with other supernovae from Poznanski et al. (2002, PASP 114, 833) shows that 2006bc is approximately one magnitude bluer than was observed in the displayed supernovae. The similarity of the colors with the type-II-P supernova 2005cs (Brown et al., in preparation) and the type-II SN 2006at (Brown and Immler, http://www.astronomerstelegram.org/?read=771) at similar epochs indicate that SN 2006bc is a type-II supernova. Further Swift observations are scheduled. Editor's note: the offset of 2006bc from the center of NGC 2397 as given on IAUC 8693 is a correction by Immler to that given by Martin on CBET 446. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2006 CBAT 2006 March 28 (CBET 451) Daniel W. E. Green