Electronic Telegram No. 2669 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION CBAT Director: Daniel W. E. Green; Hoffman Lab 209; Harvard University; 20 Oxford St.; Cambridge, MA 02138; U.S.A. e-mail: cbatiau@eps.harvard.edu (alternate cbat@iau.org) URL http://www.cbat.eps.harvard.edu/index.html Prepared using the Tamkin Foundation Computer Network SUPERNOVA 2011ao IN IC 2973 = PSN J11535103+3321463 A. Kroes, J. Newton, and T. Puckett report the discovery of an apparent supernova (mag 17.1) on an unfiltered CCD image (limiting mag 19.0) taken with a 0.40-m reflector at Portal, AZ, U.S.A., on Mar. 3.434 UT in the course of the Puckett Observatory Supernova Search. The new object is located at R.A. = 11h53m51s.03, Decl. = +33o21'46".3 (equinox 2000.0), which is 2".9 east and 9".9 south of the center of IC 2973. When the presumed supernova was posted at the Central Bureau's TOCP webpage, it was assigned the designation PSN J11535103+3321463; based on the spectroscopic report below, it is here given the designation SN 2011ao. Additional unfiltered CCD magnitudes for 2011ao: Feb. 11, [19.1 (Puckett); Mar. 4.344, 16.7 (Puckett); Mar. 5.514, 15.6 (J. Brimacombe, Cairns, Australia; remotely using a 51-cm RCOS telescope + STL11K camera at New Mexico Skies Observatory, Mayhill, NM, U.S.A.; position end figures 51s.01, 46".2). Brimacombe has posted his image at website URL http://www.flickr.com/photos/43846774@N02/5499034377/. The peculiar type-Ic supernova 1991A also appeared in IC 2973 (cf. IAUCs 5153, 5155, 5169). D. K. Sahu and Sonam Arora, Indian Institute of Astrophysics, Bangalore, report that a spectrum (wavelength range 350-750 nm) of PSN J11535103+3321463 = 2011ao was obtained on Mar. 5.99 UT with the Indian Astronomical Observatory's 2-m Himalayan Chandra Telescope (+ HFOSC). Using the SNID code of Blondin and Tonry (2007, Ap.J. 666, 1024), the spectrum of 2011ao is found to be that of a normal type-Ia supernova, with a best match that of SN 2003du at about a week before maximum light. The velocity corresponding to the minimum of the Si II 635.5-nm absorption feature is estimated as 16000 km/s. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2011 CBAT 2011 March 7 (CBET 2669) Daniel W. E. Green