Electronic Telegram No. 847 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A. IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions) CBAT@CFA.HARVARD.EDU (science) URL http://cfa-www.harvard.edu/iau/cbat.html SUPERNOVA 2007Z IN PGC 16993 E. J. Christensen, Lunar and Planetary Laboratory, reports his discovery of an apparent supernova (mag approximately 17.5) on four unfiltered CCD images obtained with the Mt. Lemmon Survey 1.5-m telescope on Feb. 17.221-17.237 UT. The new object is located at R.A. = 5h15m42s.68, Decl. = +19o21'49".5 (equinox 2000.0), which is 10".4 west and 2".7 north of the center of the apparent host galaxy (which itself has position end figures 43s.42, 46".8). Nothing is visible at this position on survey images from Jan. 25 (limiting mag approximately 21.5) or on a Digitized Sky Survey image. Following posting of this object at the Central Bureau's unconfirmed-objects webpage, H. Naito (Nishi-Harima Astronomical Observatory) and H. Yamaoka (Kyushu University) report that a confirming image was obtained by Naito on Feb. 18.423 with the 2.0-m NAYUTA telescope (+ MINT with R-band filter), showing 2007Z at mag about 17.5. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2007 CBAT 2007 February 18 (CBET 847) Daniel W. E. Green