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THE ASTRONOMER Electronic Circular No 2339      2007 May 24 14.13UT
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 2007ck IN MCG +05-43-16
An e-mail has been received from Tom Boles of Coddenham, England 
reporting his discovery of a variable object in the galaxy
MCG +05-43-16 during the course of searches for the UK Nova/Supernova 
Patrol.

The object, of magnitude 18.5, was found on an unfiltered CCD image of 
2007 May 19.037UT using a 0.35-m Schmidt-Cassegrain telescope. The 
measured position is:
RA 18h 23m 05.59s +/- 0s.01, DEC +29 54' 01.0" +/- 0".2 (2000),
which is approximately 17.9" E and 4.2" S of the centre of the host 
galaxy

Tom reports that it was not recorded on his images of 2006 June 30 and 
September 18 to a limit of magnitude 19.5. It is also absent from  the 
Digitised Sky Survey plates of 1989 May 3 (limiting red mag 20.5) and 
1990 July 22 (limiting blue mag 21.0), though there is a faint stellar 
object or compact luminous area of mag 20.5 within 1" of the possible 
supernova.

Tom obtained a follow-up image on May 19.973UT showing the object at 
magnitude 18.3. Ron Arbour, South Wonston, England also reports that 4 
images of 30 seconds each with a 0.40-m Newtonian f/5 + SXV H9 CCD 
obtained on May 23.988UT also recorded the object.

In response to an appeal from CBAT, A. Domokos and P. Wiegert obtained 
three V-band images with the 1.82-m Plaskett Telescope of the National 
Research Council of Canada, which show a new point source of magnitude V 
= 17.98 (+/- 0.03) located at the above position.

S. Blondin et. al., Harvard-Smithsonian Center for Astrophysics, report 
on CBET 971 that a spectrogram (range 350-740 nm) obtained by P. Berlind 
on May 23.39 UT with the F. L. Whipple Observatory 1.5-m telescope (+ 
FAST), shows it to be a type-II supernova roughly one month past 
explosion.  The spectrum is similar to that of the type-II-plateau 
supernova 2004et at 28 days past explosion. Adopting a recession 
velocity of 8083 km/s for the host galaxy of 2007ck the maximum 
absorption in the H_beta line (rest 486.1 nm) is blueshifted by roughly 
8500 km/s.

Congratulations to Tom on the discovery of his 106th supernova 
discovery.

Guy M Hurst