Electronic Telegram No. 1784 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://www.cfa.harvard.edu/iau/cbat.html SUPERNOVA 2009ds IN NGC 3905 S. Nakano, Sumoto, Japan, reports the discovery by Koichi Itagaki (Teppo-cho, Yamagata, Japan) of an apparent supernova (mag 16.8) on numerous unfiltered 20-s CCD frames (limiting magnitude 19.0) taken on Apr. 28.56 UT using a 0.60-m f/5.7 reflector. The new object, designated 2009ds, is located at R.A. = 11h49m04s.11, Decl. = -9o43'44".9 (equinox 2000.0), which is 12" west and 3" north of the center of NGC 3905. Nothing is visible at this position on an exposure by Itagaki from Mar. 17.59 (limiting mag 18.5) or on Digitial Sky Survey (DSS) images. Nakano adds that K. Kadota (Ageo, Japan, 0.25-m f/5 reflector) obtained sixteen unfiltered CCD images (limiting mag 17.9) on Apr. 28.684 that show 2009ds at mag 16.6 with position end figures 04s.12, 45".2. Following posting on the Central Bureau's unconfirmed-objects webpage, W. Wells of Oklahoma writes that his 300-s unfiltered CCD image obtained remotely with a 0.30-m Dall-Kirkham Cassegrain telescope near Mayhill, NM, USA, reveals mag 16.4 and position end figures 04s.2, 45".1 for 2009ds; he has posted an image of the new object at URL http://www.flickr.com/photos/32839122@N02/3484706529/. Also, M. Nissinen and V.-P. Hentunen (Varkaus, Finland) report unfiltered and R-band CCD images (limiting red mag 17.1) taken on Apr. 29.20 with a 0.25-m f/3.4 astrograph yield red mag 15.9 and position end figures 04s.02, 44".6, adding that nothing is visible at this position on a red Palomar Sky Survey image (via the DSS). NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2009 CBAT 2009 April 29 (CBET 1784) Daniel W. E. Green