Electronic Telegram No. 2505 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 2010iw NEAR UGC 4570 Stanley C. Howerton, Arkansas City, KS, U.S.A.; A. J. Drake, S. G. Djorgovski, A. Mahabal, M. J. Graham, and R. Williams, California Institute of Technology; J. L. Prieto, Carnegie Observatories; M. Catelan, Pontificia Universidad Catolica de Chile; E. C. Beshore and S. M. Larson, Lunar and Planetary Laboratory, University of Arizona; and E. Christensen, Gemini Observatory, report the discovery by Howerton of an apparent supernova in public Catalina Sky Survey (CSS) images: SN 2010 UT R.A. (2000.0) Decl. Mag. Offset 2010iw Oct. 14.66 8 45 15.01 +27 49 21.8 16.4 12".9 W, 3".4 S Further magnitudes for 2010iw: June 11.16 UT, [19.0 (CSS); Oct. 17.50, 16.3 (Howerton, remotely with a 0.6-m LB-1 telescope, Rodeo, NM, U.S.A.). They note that the new object lies 5".4 east and 1".1 north from a galaxy seen in Sloan Digital Sky Survey images with measured redshift z = 0.109; the current luminosity of 2010iw appears too high for it to be a regular supernova associated with this distant galaxy. The host galaxy is thus is likely to be UGC 4570 (at redshift z = 0.0215). NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2010 CBAT 2010 October 18 (CBET 2505) Daniel W. E. Green