Electronic Telegram No. 2830 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 2011fx IN PGC 1170 = PSN J00175956+2433460 F. Ciabattari and E. Mazzoni, Borgo a Mozzano, Italy, report the discovery of a possible supernova (mag 17.6) on unfiltered CCD images (limiting mag 18.8) obtained on Aug. 30.05 UT with a 0.5-m Newtonian telescope in the course of the Italian Supernovae Search Project. The new object is located at R.A. = 00h17m59s.56, Decl. = +24d33'46".0 (equinox 2000.0; astrometry with respect to UCAC-2 stars), which is 3" west of the center of the galaxy PGC 1170. Nothing is visible at this position on digitized plates of the Palomar Sky Survey from 1952 Aug. 22 (F plate; limiting magnitude 20.3) and 1993 Sept. 15 (J plate; limiting magnitude 20.3). The variable was designated PSN J00175956+2433460 when it was posted at the Central Bureau's TOCP webpage and is here designated SN 2011fx based on the spectroscopic report below. Additional unfiltered CCD magnitudes for 2011fx: Aug. 30.94, 17.5 (Ciabattari and Mazzoni; limiting mag 19.4); 31.18, 17.5 (R. A. Koff, Bennett, CO, U.S.A.; Meade 0.25-m f/10 Schmidt-Cassegrain reflector; position end figures 59s.52, 45".4; image at URL http://antelopehillsobservatory.org/SNpictures/PSNJ00175956+2433460final.jpg); Sept. 3.236, 16.6 (J. Brimacombe, Cairns, Australia; position end figures 59s.50, 45".5). Brimacombe's image is posted at the following website URL: http://www.flickr.com/photos/43846774@N02/6108140961/. L. Tomasella, S. Valenti, P. Ochner, S. Benetti, and E. Cappellaro, Osservatorio Astronomico di Padova, Istituto Nazionale di Astrofisica; and A. Pastorello, Dipartimento di Astronomia, Universita di Padova, on behalf of a larger collaboration, report that a spectrogram (range 360-810 nm; resolution 2.2 nm) of PSN J00175956+2433460 = SN 2011fx, obtained on Sept. 23.91 UT, shows a blue continuum with narrow (FWHM about 2200 km/s) H lines in emission, typical of a young type-IIn supernova. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2011 CBAT 2011 September 26 (CBET 2830) Daniel W. E. Green