Electronic Telegram No. 2290 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION CBAT Director: Daniel W. E. Green; Room 209; Dept. of Earth and Planetary Sciences; Harvard University; 20 Oxford St.; Cambridge, MA 02138; U.S.A. e-mail: cbat@iau.org; cbatiau@eps.harvard.edu URL http://www.cfa.harvard.edu/iau/cbat.html SUPERNOVA 2010db P. Balanutsa and E. Gorbovskoy, on behalf of the MASTER team (cf. CBETs 2111, 2162), report their discovery of an apparent supernova (mag 15.2) on an unfiltered CCD image (limiting mag 18.8) taken on May 15.923 UT. The new object is located at R.A. = 18h26m09s.27, Decl. = +30d14'12".6 (equinox 2000.0), which is 3".5 west and 1".5 south of the center of PGC 1895764. The discovery image has been posted at the following website URL: http://observ.pereplet.ru/images/SN100518/SN100518_all.jpg. After posting on the CBAT's unconfirmed-objects webpage, P. Corelli (Pagnacco, Italy) reports that two co-added 120-s unfiltered frames obtained with a 0.45-m f/4.5 telescope on May 23.958 show an object of mag 16.0 located 7" west and 2" south of the nucleus of PGC 1895764, at position end figures 09s.2, 12".2, adding that nothing is visible at this position on a Palomar Sky Survey plate (limiting red mag approximately 21). NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2010 CBAT 2010 May 24 (CBET 2290) Daniel W. E. Green