2011CBET.2741....1C

Fabrizio Ciabattari, S. Donati, M. Giovannini, E. Mazzoni, G. Petroni, and M. Rossi, Borgo a Mozzano, Italy, report their discovery of a point-like source on unfiltered CCD images (limiting mag 18.5-18.8) obtained on May 12.09 (when the object appeared at mag 16.5) and 13.02 UT with a 0.5-m Newtonian telescope, the object measured to be located at R.A. = 21:00:42.28, Decl. = +17:48:22.5 (equinox 2000.0; astrometry with respect to UCAC-2 stars), which is 2" west and 4" north of the center of the galaxy NGC 7003. Nothing was visible at this position on images taken by Ciabattari et al. during June 2010-Nov. 2010 (limiting magnitude 18.8). The object was designated PSN J21004220+1748220 and is here designated SN 2011dk based on the spectroscopic report below. Additional magnitudes for 2011dk: 1990 Aug. 14, [20.3 (Palomar Sky Survey, J plate; via Ciabattari et al.); 1992 Aug. 24, [20.3 (Palomar Sky Survey, F plate; via Ciabattari et al.); 2011 May 13.02, 16.6 (Ciabattari et al.); 13.447, 16.8 (Joseph Brimacombe, Cairns, Australia; remotely using a 51-cm RCOS telescope + STL11K camera at the New Mexico Skies Observatory near Mayhill, NM, U.S.A.; position end figures 42s.24, 22".5). Brimacombe's image is posted at website URL http://www.flickr.com/photos/43846774@N02/5716853049/.