Electronic Telegram No. 1640 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 SUPERNOVAE 2008im AND 2008io P. Challis, Harvard-Smithsonian Center for Astrophysics (CfA), on behalf of the CfA Supernova Group reports that a spectrum (range 320-850 nm) of 2008im (cf. CBET 1635), obtained on Dec. 29 UT by M. Calkins with the F. L. Whipple Observatory 1.5-m telescope (+ FAST), shows it to be a type-Ib supernova; cross-correlation with a library of supernova spectra, using the "Supernova Identification" code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024), indicates that 2008im is consistent with other type-Ib supernovae at maximum light. A spectrogram, obtained as above on Dec. 30 UT by P. Berlind, shows 2008io (cf. CBET 1639) to be a type-Ia supernova; cross-correlation with a library of supernova spectra, using the SNID code, indicates that 2008io is a normal type-Ia supernova about 50 days past maximum light. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2008 CBAT 2008 December 31 (CBET 1640) Daniel W. E. Green