Supernova 2010ec in NGC 655

J. Maza, M. Hamuy, R. Antezana, L. Gonzalez, P. Gonzalez, S. Silva, G. Folatelli, R. Cartier, F. Forster, and S. Marchi, Universidad de Chile; G. Pignata and M. Cifuentes, Universidad Andres Bello; 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 17.1 +/- 0.3) on an unfiltered image taken on June 5.40 UT with the 0.41-m 'PROMPT 3' telescope located at Cerro Tololo. The new object, which is also present at mag approximately 17.0 in an image taken on June 8.44, is located at R.A. = 1h41m55s.93 +/- 0".1, Decl. = -13o05'01".6 +/- 0".1 (equinox 2000.0), which is about 11".8 east and 7".4 south of the center of the galaxy NGC 655. Nothing is visible at this position on archival images taken on 2009 Oct. 13.17 and Nov. 20.21 (limiting mag 18.5).