Electronic Telegram No. 573 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 SUPERNOVAE 2006do AND 2006dn The "Nearby Supernova Factory" collaboratoin (P. Antilogus, S. Gilles, R. Pain, and R. Pereira, Laboratoire de Physique Nucleaire et de Haute Energies de Paris; N. Blanc, Y. Copin, E. Gangler, and G. Smadja, Institut de Physique Nucleaire de Lyon; G. Aldering, C. Aragon, S. Bailey, S. Bongard, M. J. Childress, D. Kocevski, S. Loken, P. Nugent, S. Perlmutter, K. Runge, R. Scalzo, R. C. Thomas, L. Wang, and B. A. Weaver, Lawrence Berkeley National Laboratory, Berkeley; E. Pecontal and G. Rigaudier, Centre de Recherche Astronomique de Lyon; R. Kessler, Kavli Institute for Cosmological Physics, Chicago; and C. Baltay, A. Bauer, D. Herrera, and D. Rabinowitz, Yale University) reports the classification of two supernovae using spectra (range 320-1000 nm) obtained with the Supernova Integral Field Spectrograph on the University of Hawaii 2.2-m telescope. The spectrum of SN 2006dn in UGC 12188 (cf. CBET 571), obtained July 8.5 UT, reveals that it is of type Ib, similar to that of SN 1990I at 12 days after maximum (Elmhamdi et al. 2004, A.Ap. 429, 963). The spectrum shows strong contamination from an underlying H II region, the emission lines of which were used to constrain the host redshift to z = 0.017. The spectrum of SN 2006do (cf. CBET 572) in ESO 470-G18 (z = 0.02843, Da Costa et al. 1991, Ap.J. Suppl. 75, 935, via NED), obtained on July 8.6, indicates that it is a normal type-Ia event at 2-3 days before maximum, similar to SN 1994D or SN 1996X at that phase. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2006 CBAT 2006 July 10 (CBET 573) Daniel W. E. Green