Electronic Telegram No. 2197 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION CBAT Director: Daniel W. E. Green; Room 209; Dept. of Earth and Planetary Sciences; Harvard University; 20 Oxford St.; Cambridge, MA 02138; U.S.A. e-mail: cbat@iau.org; cbatiau@eps.harvard.edu URL http://www.cfa.harvard.edu/iau/cbat.html SUPERNOVA 2010af IN NGC 3172 Uday K. Gurugubelli, G. C. Anupama, D. K. Sahu, S. Arora, and P. Anto, Indian Institute of Astrophysics, Bangalore, report that a low-resolution spectrogram (range 350-920 nm) of 2010af (cf. CBET 2194), obtained on Mar. 9.9 UT with the Indian Astronomical Observatory's 2-m Himalayan Chandra Telescope (+ HFOSC), shows it to be a type-Ia supernova at about 2-3 days from maximum light. Assuming a recession velocity of 6096 km/s for the host galaxy, NGC 3172 (Emilio et. al. 1999, PASP 111, 438; via NED), the velocity corresponding to the Si II 615.0-nm line is 10200 km/s. Using the SNID code (Blondin and Tonry 2007, Ap.J. 666, 1024), the spectrum of 2010af is found to be similar to that of SN 1991bg close to maximum light. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2010 CBAT 2010 March 11 (CBET 2197) Daniel W. E. Green