7 April 2010
IAU Electronic Telegram No.2231
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SUPERNOVA 2010bk IN NGC 4433
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J. Maza, M. Hamuy, R. Antezana, L. Gonzalez, P. Gonzalez, S. Silva, G.
Folatelli, R. Cartier, F. Forster, S. Marchi, and A. Rojas, 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 17.6 +/- 0.4) on an unfiltered image
taken on Apr. 4.19 UT with the 0.41-m 'PROMPT 5' telescope located at Cerro
Tololo. The new object, which is also present at mag approximately 17.8 in
images taken on Apr. 5.18 and 7.01, is located at R.A. = 12h27m38s.47 +/-
0".1, Decl. = -8o16'39".3 +/- 0".1 (equinox 2000.0), which is about 2".8
west and 9".9 north of the center of the galaxy NGC 4433. Nothing is
visible at this position in archival images taken on Apr. 1.19 (limiting
mag 17.5) or on a stack of archival images taken between 2009 Mar. 12.22
and 2010 Mar. 29.20 (limiting mag 20.0).
NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.
2010 April 7 (CBET 2231) Michael Rudenko