Electronic Telegram No. 2953 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 2011jh IN NGC 4682 = PSN J12471442-1003473 S. Nakano, Sumoto, Japan, reports the discovery by Yoji Hirose (Tsutsumi, Chigasaki, Kanagawa-ken, Japan) of an apparent supernova (mag 16.7) on unfiltered CCD frames (limiting magnitude 17.5) taken on Dec. 22.784 UT using a 0.35-m f/5.7 Schmidt-Cassegrain reflector (+ SBIG ST9XEi camera). The new object is located at R.A. = 12h47m14s.42, Decl. = -10d03'47".3 (equinox 2000.0), which is 18" west and 1" north of the center of the galaxy NGC 4682 (whose center is measured at position end figures 15s.6, 48".5). Nothing is visible at this position on the Digitized Sky Survey (no date or bandpass provided). The variable was designated PSN J12471442-1003473 when it was posted at the Central Bureau's TOCP webpage and is here designated SN 2011jh based on the spectroscopic confirmation reported below. Additional unfiltered CCD magnitudes for 2011jh: Apr. 24, [17.5 (Hirose); Dec. 23.761, 15.7 (T. Noguchi, Katori, Chiba-ken, Japan; 0.23-m f/6.3 Schmidt-Cassegrain reflector + BITRAN BT-11E camera; limiting magnitude 17.5; position end figures 14s.41, 46".3; offset 16" west, 2" north; communicated by Nakano; image posted at URL http://park8.wakwak.com/~ngc/images/PSNinNGC4682.jpg); 24.838, 16.0 (Hirose). L. Tomasella, S. Valenti, S. Benetti, F. Bufano, M. Fiaschi, A. Pastorello, and P. Ochner, Osservatorio Astronomico di Padova, Istituto Nazionale di Astrofisica, on behalf of a larger collaboration, report that a spectrogram of PSN J12471442-1003473 = SN 2011jh, obtained on Dec. 24.20 UT with the Asiago 1.82-m Copernico Telescope (+ AFOSC; range 350-820 nm; resolution 2.4 nm), suggests that 2011jh is a type-Ia supernova several days before maximum. The best fits to these spectra found by GELATO (Harutyunyan et al. 2008, A.Ap. 488, 383; available at https://gelato.tng.iac.es/login.cgi) suggest that 2011jh is similar to SN 2002bo (Benetti et al 2004, MNRAS 348, 261) at 10 days before maximum. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2011 CBAT 2011 December 25 (CBET 2953) Daniel W. E. Green