Electronic Telegram No. 420 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://cfa-www.harvard.edu/iau/cbat.html SUPERNOVA 2006ar IN MCG +11-13-36 T. Boles, Coddenham, England, reports the discovery of an apparent supernova (mag 18.2) on unfiltered CCD images taken on Mar. 5.907 and 6.947 UT with a 0.35-m reflector. The new object is located at R.A. = 10h37m30s.75, Decl. = +65o00'58".1 (equinox 2000.0), which is approximately 8".1 west and 7".5 south of the center of MCG +11-13-36. Nothing is visible at this location on Boles' images from 2005 Jan. 4 and Apr. 3 (limiting mag 19.5) or on Digitized Sky Survey plates from 1996 Dec. 7 (limiting blue mag 20.5) and 1997 Jan. 10 (limiting red mag 21.0). NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2006 CBAT 2006 March 6 (CBET 420) Daniel W. E. Green