Electronic Telegram No. 139 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 2005bl IN NGC 4059 N. Morrell, G. Folatelli, M. Phillips, C. Contreras, and M. Hamuy, Carnegie Supernova Project, report that an optical spectrum (range 320-940 nm) of SN 2005bl (cf. IAUC 8512), obtained on Apr. 16.13 UT with the Las Campanas 2.5-m du Pont telescope (+ WFCCD spectrograph), reveals it to be a type-Ia supernova similar to the subluminous SN 1999by, probably a few days before maximum light. Strong Ti II absorption troughs are present at about 420 and 590 nm. The expansion velocity derived from the minimum of the Si II 635.5-nm line is 11000 km/s, assuming the recession velocity for NGC 4059 given by the NED database. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the formal IAU Circulars. (C) Copyright 2005 CBAT 2005 April 17 (CBET 139) Daniel W. E. Green