Electronic Telegram No. 2541
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 2010jn IN NGC 2929
     The Central Bureau has received reports of the independent discoveries of
an apparent supernova in NGC 2929 on unfiltered CCD images -- the first by T.
Boles (Coddenham, England, 0.35-m reflector), and the second by J. Newton and
T. Puckett (0.40-m reflector at Portal, AZ, U.S.A.).  Boles reports the
position of 2010jn as R.A. = 9h37m30s.24, Decl. = +23o09'33".3, which is
approximately 5".9 east and 8".7 south of the center of NGC 2929; Puckett
provides position end figures 30s.20, 33".6 (offset 4".6 east and 8".5 south
of the center of NGC 2929).  Available magnitudes, from unfiltered CCD images
unless noted otherwise:  1995 Nov. 30, [21.0 (Digitized Sky Survey, blue
plate; via Boles); 1998 Apr. 22, [20.5 (DSS, red plate; via Boles); 2009 Jan.
6, [19.5 (Boles); 2009 Oct. 4, [19.9 (Puckett); 2010 Oct. 21.160, 17.0 (Boles;
discovery); Nov. 5.47, 17.2 (Newton and Puckett; discovery); 6.48, 16.9
(Puckett).  Boles subsequently noted that 2010jn was reported by Howell et
al. (see website URL http://www.astronomerstelegram.org/?read=2934), where
they reported position end figures 30s.30, 33".6 and the following R-band
magnitudes:  Oct. 8.5, [20.3; 11.5, 19.6 (marginal); 12.5, 19.2 (discovery);
13.5, 18.7.  Howell et al. add that a spectrogram obtained on Oct. 13 with
the "Gemini North" telescope showed 2010jn to be a type-Ia supernova around
15 days before maximum light, noting that the blueshift of the Si II 635.5-nm
feature indicates velocities in excess of 20000 km/s ("among the highest
ever seen for non-detached features" in a type-Ia event).


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2010 CBAT
2010 November 7                  (CBET 2541)              Daniel W. E. Green