Circular No. 8251 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION Mailstop 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 ISSN 0081-0304 Phone 617-495-7440/7244/7444 (for emergency use only) SUPERNOVAE 2003kj-2003kv P. Challis, Center for Astrophysics, on behalf of the ESSENCE project (cf. IAUC 8237, 8021, 8034), reports the discovery of 13 supernovae on multiple R- and I-band images taken at the Blanco 4-m telescope during Nov. 15-30 by project members. Spectroscopy -- obtained on Nov. 15-30 with the Very Large Telescope (+ FORS1), Gemini telescope (+ GMOS), and Magellan (+ IMACS and + LDSS2) reflectors -- shows all except SN 2003kj (which is of type II) to be of type Ia. Included below are measured redshifts; each new supernova is within 1"-2" of its host-galaxy center. SN 2003 UT R.A. (2000.0) Decl. Mag. z 2003kj Nov. 15 1 14 36.56 - 0 23 58.2 22.3 0.1 2003kk Nov. 15 23 25 36.06 - 9 31 44.7 20.3 0.2 2003kl Nov. 17 1 09 48.80 + 1 00 05.6 21.0 0.3 2003km Nov. 19 2 30 09.00 - 9 04 35.9 21.8 0.3 2003kn Nov. 21 2 09 15.55 - 3 35 41.4 21.3 0.2 2003ko Nov. 21 2 11 06.48 - 3 47 56.1 21.7 0.4 2003kp Nov. 21 2 31 02.64 - 8 39 50.8 22.1 0.6 2003kq Nov. 21 2 31 04.09 - 8 10 56.6 22.6 0.6 2003kr Nov. 21 2 31 20.96 - 8 36 14.2 22.0 0.4 2003ks Nov. 21 2 31 34.54 - 8 36 46.4 22.2 0.5 2003kt Nov. 21 2 33 47.01 - 8 36 22.1 22.8 0.6 2003ku Nov. 23 1 08 36.25 - 0 33 20.8 22.9 0.8 2003kv Nov. 27 2 09 42.52 - 3 46 48.6 23.4 0.8 2003 UN_284 R. L. Millis, Lowell Observatory, on behalf of the Deep Ecliptic Survey team, reports that the recently reported transneptunian object 2003 UN_284 (cf. MPEC 2003-X20) is a binary system. Scrutiny by K. B. Clancy (Massachusetts Institute of Technology) of two images taken on Oct. 24 UT at the Kitt Peak 4-m Mayall Telescope (+ MOSAIC camera) revealed the two objects having a separation of 2".01 +/- 0".11 and a broad-VR-bandpass-magnitude difference of 0.59 +/- 0.21 mag, the fainter component lying in p.a. 305 +/- 3 deg relative to the brighter component. Subsequent observations on Nov. 20 (two images) and Nov. 24 (two images) with the same instrumentation yielded corresponding values of 1".93 +/- 0".10, 0.70 +/- 0.15 mag, and p.a. 299 +/- 3 deg. The brighter component has R approximately 23.2. Additional astrometric and photometric observations of 2003 UN_284 are encouraged. (C) Copyright 2003 CBAT 2003 December 5 (8251) Daniel W. E. Green