Electronic Telegram No. 2664 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 2011aj IN NGC 6246A = PSN J16501398+5522280 Zhangwei Jin (Ningbo, Zhejiang, China) and Xing Gao (Urumqi, Xinjiang, China) report the discovery of an apparent supernova (mag approximately 17.3) near the galaxy NGC 6246A = PGC 59090 on a 60-s survey image (limiting mag about 19.0) taken by Xing Gao in the course of the Xingming Observation Sky Survey around Feb. 18.922 UT using an unfiltered CCD with a Celestron C14 0.35-m Schmidt-Cassegrain telescope at Mt. Nanshan. The new object, which was designated PSN J16501398+5522280 when posted on the Central Bureau's TOCP webpage and is here designated SN 2011aj (based on the spectroscopy reported below), is located at R.A. = 16h50m13s.98, Decl.= +55d22'28".0 (equinox 2000.0). Additional approximate magnitudes (unfiltered CCD unless noted otherwise): 1992 June 29, [19.5 (Digitized Sky Survey; via Jin and Gao); 2011 Feb. 16.924, 17.7 (Jin and Gao); 22.397, 16.6 (J. Brimacombe, Cairns, Australia; remotely using a robotic 0.51-m RCOS telescope + SBIG STL11K CCD camera near Mayhill, NM, U.S.A.; position end figures 14s.01, 28".5). The discoverers have posted their images of 2011?? at URL http://www.xjltp.com/XOSS/XM18ZJ/XM18ZJ.htm. G. H. Marion, Harvard-Smithsonian Center for Astrophysics (CfA), on behalf of the CfA Supernova Group, reports that a spectrogram (range 340-740 nm) of 2011aj was obtained on Mar. 2 UT by P. Berlind with the F. L. Whipple Observatory 1.5-m telescope (+ FAST). Cross-correlation with a library of supernova spectra using the "Supernova Identification" code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024) shows that 2011aj is a type-Ia supernova a few days past maximum; the velocity of the Si II 635.5-nm feature, measured at the absorption minimum, is 8800 km/s. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars.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 3 (CBET 2664) Daniel W. E. Green