2009CBET.1875....1Y

F. Yuan, University of Michigan; J. Vinko, University of Texas; R. Quimby, California Institute of Technology; D. Chamarro, M. D. Sisson, C. Akerlof, and S. B. Pandey, University of Michigan; and J. C. Wheeler and E. Chatzopoulos, University of Texas, on behalf of the ROTSE collaboration, report the discovery of an apparent supernova (mag about 17.0) in unfiltered CCD images taken on July 11.90 and 12.89 UT with the 0.45-m ROTSE-IIIc telescope at the H.E.S.S. site in Namibia. The new object is located at R.A. = 20:38:37.42, Decl.= -25:06:56.0 (equinox 2000.0), which is 26" west and 33" north of the center of the galaxy MCG -04-48-26; 2009hk is slightly blended with an object (of red magnitude about 18.2 in the USNO-B1.0 catalogue) to its southeast in the ROTSE-III images. No source was detected at this position in the Digitized Sky Survey images (no limiting magnitude or bandpass provided) or a ROTSE-III reference image (limiting magnitude about 19.3) constructed from images taken between June and Aug. 2008. A finding chart of the transient is posted at the following website URL: http://www.rotse.net/rsvp/j203837.4-250656/j203837.4-250656.jpg.