Electronic Telegram No. 1718
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
CBAT@CFA.HARVARD.EDU (science)
URL http://www.cfa.harvard.edu/iau/cbat.html


SUPERNOVA 2009at IN NGC 5301
     S. Nakano, Sumoto, Japan, reports the discovery by Toshihide Noguchi
(Tsunomiya, Katori, Chiba-ken) of an apparent supernova (mag 16.5) on
numerous 50-s unfiltered CCD frames taken on Mar. 11.633 UT using a 0.23-m
f/6.3 Schmidt-Cassegrain reflector (limiting magnitude 18.0).  The new
object is located at R.A. = 13h46m26s.68, Decl. = +46o06'09".1, which is 21"
east and 15" south of the center of NGC 5301; nothing is visible at this
position on his exposure from 2005 Jan. 10 (limiting mag 18.5) or on the
Digitized Sky Survey (DSS).  Nakano notes that K. Kadota (Ageo, Japan) has
confirmed 2009at on ten co-added unfiltered CCD frames (limiting mag 18.5)
obtained in strong moonlight with a 0.25-m f/5 reflector on Nov. 11.760,
yielding mag 16.7 and position end figures 26s.70, 08".4.  Nakano also
reports that Y. Ikari (Moriyama, Shiga-ken) obtained confirming unfiltered
CCD images on Mar. 11.773 with a 0.26-m f/7 reflector; Nakano measures mag
15.9 and position end figures 26s.67 +/- 0s.05, 08".6 +/- 0".3 from Ikari's
image (average of ten measurements), adding that Ikari also found nothing
at this position on the DSS.  Nakano further adds that K. Itagaki (Yamagata,
Japan) has found a pre-discovery image of 2009at at mag 16.5 on his unfiltered
CCD survey frame taken on Mar. 10.621 using a 0.30-m f/7.8 reflector at his
Takanezawa station at Tochigi-ken.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2009 CBAT
2009 March 12                    (CBET 1718)              Daniel W. E. Green