Electronic Telegram No. 2159 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@cfa.harvard.edu; dwe_green@eps.harvard.edu URL http://www.cfa.harvard.edu/iau/cbat.html SUPERNOVA 2010T G. Pignata, M. Cifuentes, Universidad Andres Bello; J. Maza, M. Hamuy, R. Antezana, L. Gonzalez, P. Gonzalez, P. Lopez, S. Silva, G. Folatelli, R. Cartier, F. Forster, S. Marchi, and A. Rojas, Universidad de Chile; B. Conuel, Wesleyan University; and D. Reichart, K. Ivarsen, J. Haislip, A. Crain, D. Foster, M. Nysewander, and A. LaCluyze, University of North Carolina at Chapel Hill, on behalf of the CHASE project, report the discovery of an apparent supernova (mag approximately 18.2 +/- 0.4) on an unfiltered image taken on Jan. 25.30 UT with the 0.41-m 'PROMPT 4' telescope located at Cerro Tololo. The new object, which is also present at mag approximately 18.4 in an image taken on Jan. 29.26, is located at R.A. = 13h14m47s.88 +/- 0".1, Decl. = -15o58'24".8 +/- 0".1 (equinox 2000.0), which is about 1".9 east and 2".3 south of center of the apparent host galaxy. Nothing is visible at this position on archival images taken on 2010 Jan. 2.31 (limiting mag 18.5) or in a stack of twenty 40-s images taken between 2008 Dec. 26.33 and 2009 Jun. 25.05 (limiting mag 20.5). NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2010 CBAT 2010 February 1 (CBET 2159) Daniel W. E. Green