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THE ASTRONOMER Electronic Circular No 2630      2010 Mar 22 10.10UT
Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise,  Basingstoke,
Hants, RG22 4PP,England.Telephone/FAX(01256)471074Int:+441256471074
INTERNET: GUY@TAHQ.DEMON.CO.UK      Backup: gmh@wdcc1.bnsc.rl.ac.uk
WORLD WIDE WEB                         http://www.theastronomer.org
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SUPERNOVA 2010au IN PGC 82347
On 2010 March 16 Ron Arbour of Pennell Observatory, South Wonston, 
England reported his detection of a possible supernova of magnitude 16.7 
in the galaxy PGC 82347 during searches for the UK Nova/Supernova 
Patrol. It was recorded on five subsequent frames (limiting magnitude 
18.80) on the same date around 2010 March 15.942UT using a 0.40-m f/5 
Schmidt-Cassegrain and Starlight Xpress CCD.

The new object is located at:
RA 09h 12m 36.39s DEC +34 51' 17.0" (2000), which is 2.0"E, 1.0"S from 
the centre of the host galaxy.

Nothing is visible at this position on Palomar Sky Survey plates
of 1996 Apr. 15 (limiting blue mag 20.6) and 1998 Apr. 21 (limiting red 
mag 19.1), or on Ron's own image taken on 2010 Mar. 3 (limiting mag 
19.0).

After posting on the Central Bureau's unconfirmed-objects webpage, Dave 
Balam et. al., report that observations obtained on Mar. 19.16 with the 
1.82-m Plaskett telescope (National Research Council of Canada) on 
Vancouver Island confirm a new point source located 2" east and 1" south 
of the core of the galaxy; differential magnitudes/colors (using SDSS 
filters) of 2010au, using the reference star SDSS J091241.22+345239.8, 
are as follows:  g = 17.55 +/- 0.02, g-r = +0.21 +/- 0.04, r-i = -0.80 
+/- 0.08.

Guy Hurst also secured an image with the Sierra Stars Observatory 0.61-m 
Cassegrain on March 20. The 2-minute exposure with V filter showed a 
pronounced brightening in the same quadrant of the galaxy as reported by 
Ron and quite different to the uniform brightness on Ron's master 
images. Unfortunately the very close proximity to the nucleus made 
astrometry very difficult.

Ron Arbour has also reported to us that Weidong Li (University of 
California) obtained a follow-up image taken on Mar. 21.25 with the 
Katzman Automatic Imaging Telescope at Lick Observatory which yielded an 
approximate magnitude of 18 and position end figures 36s.33, 16".8 from 
an analysis by Tom Boles. Li adds that nothing is visible at this 
position on a Sloan Digital Sky Survey image from 2002 Dec. 31 (limiting 
mag 22.0).

The object was designated SN 2010au on CBET 2217 and we offer 
congratulations to Ron on the discovery of his 23rd supernova.

Guy M Hurst