Supernova 2011ek near NGC 918 = Psn J02254889+1832000

S. Nakano, Sumoto, Japan, reports the discovery by Koichi Itagaki (Teppo-cho, Yamagata, Japan) of an apparent supernova (mag 16.4) on a unfiltered CCD frames (limiting mag 19.0) taken on Aug. 4.77 UT using a 0.60-m f/5.7 reflector (+ BITRAN BT-21 camera). The new object is located at R.A. = 2h25m48s.89, Decl. = +18d32'00".0 (equinox 2000.0), which is 27" west and 133" north of the center of NGC 918. Nothing is visible at this position on the Digitized Sky Survey (limiting mag about 20; no bandpass or date provided). The discovery image has been posted at the following website URL: http://www.k-itagaki.jp/images/psn-ngc918.jpg. The variable was designated PSN J02254889+1832000 when posted at the Central Bureau's TOCP webpage and is here designated SN 2011ek based on the spectroscopic report below. Additional unfiltered CCD magnitudes for 2011ek: 2008 Dec. 1.601, [19.5 (Itagaki; communicated by Nakano); Aug. 5.406, 16.4 (Joseph Brimacombe, Cairns, Australia; position end figures 48s.89, 32'00".0); 5.62, 16.0 (Itagaki; communicated by H. Yamaoka, Kyushu University); 5.64, 16.3 (Toshihide Noguchi, Katori, Chiba-ken, Japan; 0.23-m Schmidt-Cassegrain reflector + BITRAN BT-11E camera; communicated via Nakano; position end figures 48s.92, 31'59".3; limiting mag 17.5); 6.642, 15.8 (Itagaki; communicated by Yamaoka); 7.73, 16.6 (K. Kadota, Ageo, Japan; 0.25-m f/5 reflector + SBIG ST-9E camera; communicated via Nakano; position end figures 48s.88, 31'59".5; limiting mag 18.0); 8.735, 16.1 (M. Tsuboi, Hiroshima, Japan; communicated by Nakano). Kadota's image is located at http://members.jcom.home.ne.jp/kenic-k/image/PSNinNGC918-20110807.jpg. D. D. Balam, Dominion Astrophysical Observatory, National Research Council of Canada (NRCC); M. L. Graham, Las Cumbres Observatory Global Telescope, University of California at Santa Barbara; E. Y. Hsiao, Lawrence Berkeley Laboratory; and D. W. E. Green, Harvard University, report that a spectrogram (range 383-717 nm, resolution 0.3 nm) of PSN J02254889+1832000 = 2011ek, obtained on Aug. 7.41 UT with the 1.82-m Plaskett Telescope of the NRCC, shows it to be a type-Ia supernova before maximum light. Comparison with a library of supernova spectra using the "superfit" matching program of Howell et al. (2005, Ap.J. 634, 1190) indicates that 2011ek is a normal type-Ia supernova most similar to SN 2002bo at 11 days before maximum light.