2012CBET.3253....1L

V. Lipunov, Sternberg Astronomical Institute (SAI) at Lomonosov, Moscow State University (MSU), reports the discovery by V. Shumkov of an apparent supernova (magnitude 14.5) on two 180-sec unfiltered survey images from the MASTER-Kislovodsk robotic telescope (0.40-m f/2.5 reflector + 4000x4000-pixel CCD camera) taken on Oct. 7.062 and 7.088 UT. D. Denisenko and E. Gorbovskoy (SAI/MSU) report that the new object is located at R.A. = 9:24:37.95, Decl. = +49:21:32.0 (equinox 2000.0; average of two measurements), which is 2" east and 6" north of the nucleus of NGC 2857. Nothing is visible at this position on a MASTER-Kislovodsk image from 2011 Dec. 6.933 (limiting magnitude 19.2) or on archival Digitized Sky Survey plates and a Sloan Digital Sky Survey image of the field. The comparison of the discovery and reference images is posted at website URL http://master.sai.msu.ru/static/OT/PSNinNGC2857-MASTER-anim.gif. The variable was designated PSN J09243795+4921320 when it was posted at the Central Bureau's TOCP webpage and is here designated SN 2012fg based on the 123456789 123456789 123456789 123456789 123456789 123456789 123456789 123456789 spectroscopic confirmation reported below. Additional CCD magnitudes for 2012fg: Oct. 8.390, 15.9 (L. Elenin, Lyubertsy, Russia; and I. Molotov, Moscow; images remotely taken with a 0.45-m f/2.8 telescope at the ISON-NM Observatory near Mayhill, NM, USA; limiting mag about 19.1; position end figures 38s.04 ± 0".13, 34".2 ± 0".13; NOMAD reference stars; image posted at URL http://spaceobs.org/images/TOCP/PSNJ09243795+4921320-20121008.png); 8.492, 15.8 (Joseph Brimacombe, Cairns, Australia; luminance filter; position end figures 38s.10, 34".5; image posted at the following website URL: http://www.flickr.com/photos/43846774@N02/8085920827/); 8.527, V = 16.1 (P. Camilleri, New Castle, Australia; 60-s image remotely taken at the Sierra Stars Observatory near Markleeville, CA, USA, with a 0.61-m f/10 telescope; limiting mag about 17.5; position end figures 38s.05 ± 0".3, 34".1 ± 0".3; NOMAD reference stars).

G. H. Marion, Harvard-Smithsonian Center for Astrophysics (CfA), on behalf of the CfA Supernova Group; and J. Vinko, University of Szeged, report that a spectrogram (range 340-740 nm) of PSN J09243795+4921320 = SN 2012fg was obtained on Oct. 13 UT with the F. L. Whipple Observatory 1.5-m telescope (+ FAST). The spectrum shows a generally smooth and blue continuum, as reported by Cellier-Holzem et al. (whose report is posted at website URL http://www.astronomerstelegram.org/?read=4466). Weak, broad humps are present that correlate with H Balmer and He I 587.6-nm lines at about 9000 km/s. A narrow H-alpha emission feature, due to the host galaxy (NGC 2857), suggests z = 0.0164, which is consistent with the value given in NED (from de Vaucouleurs et al. 1991, 3rd Reference Catalogue of Bright Galaxies, Ver. 3.9).