Electronic Telegram No. 3197
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 2012dy IN PGC 66545 = PSN J21185070-5738425
     Greg Bock, Windaroo, Queensland, Australia, reports the discovery of a
supernova (red mag 15.6) by Peter Marples (Loganholme, Queensland) on an
unfiltered CCD image (limiting mag 18.5) taken on Aug. 3.53 UT using a 30-cm
Meade LX200R f/7 reflector (+ Starlight Xpress camera).  The new object is
located at R.A. = 21h18m50s.70, Decl. = -57d38'42".5 (equinox 2000.0; measured
by Bock using the USNO-B and UCAC3 catalogues), which is 2".3 west and 17"
south of the nucleus of the galaxy ESO 145-4 = PGC 66545.  Nothing is visible
at this position on Digitized Sky Survey red or infrared images (limiting mag
> 19).  The variable was designated PSN J21185070-5738425 when it was posted
at the Central Bureau's TOCP webpage and is here designated SN 2012dy based
on the spectroscopic confirmation reported below.  Additional magnitudes for
2012dy:  2012 July 27, [18.5 (Stuart Parker, Oxford, Canterbury, New Zealand;
30-s unfiltered red image; reported by Bock); Aug. 3.667, 16.6 (Joseph
Brimacombe, Cairns, Australia; infrared image, bandpass > 700 nm; position
end figures 50s.73, 42".4; image posted at the following website URL:
http://www.flickr.com/photos/43846774@N02/7708311920/); 4.475, 16.3
(Brimacombe; position end figures 50s.72, 41".7; image posted at website URL
http://www.flickr.com/photos/43846774@N02/7713955784/).

     D. Milisavljevic, Harvard-Smithsonian Center for Astrophysics (CfA); J.
T. Parrent, Dartmouth College and Las Cumbres Observatory; R. Fesen, Dartmouth
College; R. Margutti and A. Soderberg, CfA; and T. Pickering and P. Kotze,
South African Astronomical Observatory, report that low-dispersion spectra
(range 320-900 nm), obtained on Aug 5.08 UT with the 10-m SALT telescope (+
RSS), show PSN J21185070-5738425 = SN 2012dy to be a type-II supernova not
long after outburst.  Broad P-Cyg features associated with H_alpha, Na I, and
Ca II are observed over top a fairly blue continuum.  Assuming a redshift of
z = 0.010 for the host galaxy, ESO 145-4 (Mathewson and Ford 1996, Ap.J.
Suppl. 107, 97), they estimate the velocity of the H_alpha absorption feature
to be approximately 22000 km/s.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2012 CBAT
2012 August 8                    (CBET 3197)              Daniel W. E. Green