Electronic Telegram No. 458 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 2006ba IN NGC 2980 S. Blondin, M. Modjaz, R. Kirshner, and P. Challis, Harvard-Smithsonian Center for Astrophysics, report that a spectrum (range 350-740 nm) of SN 2006ba (cf. CBET 443, IAUC 8693), obtained on Apr. 2.26 UT by V. Antoniou with the F. L. Whipple Observatory 1.5-m telescope (+ FAST), shows it to be a type-IIb supernova. The spectrum is dominated by broad P-Cyg profiles of He I and of the Balmer series. Cross-correlation with a library of supernova spectra indicates that SN 2006ba is similar to SN 1993J at 34 days past explosion (Matheson et al. 2000, A.J. 120, 1487); a comparison of spectra can be seen at http://cfa-www.harvard.edu/oir/Research/ supernova/spectra/sn2006ba_vs_sn1993J.gif. Adopting a recession velocity of 5736 km/s for the host galaxy (Mathewson and Ford 1996, Ap.J. Suppl. 107, 97), the maximum absorption in the H_alpha line (rest 656.3 nm) is blueshifted by 13000 km/s. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2006 CBAT 2006 April 3 (CBET 458) Daniel W. E. Green