Electronic Telegram No. 681 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 (6244) OKAMOTO D. Higgins, Canberra, Australia; D. Pray, Carbuncle Hill Observatory, Greene, RI; P. Kusnirak and P. Pravec, Ondrejov Observatory, report that photometric observations obtained during Sept. 26-Oct. 17 reveal that minor planet (6244) is a binary system with an orbital period of 20.32 +/- 0.01 hours. The primary rotates with a period of 2.8958 +/- 0.0001 hours, and it has a lightcurve amplitude of 0.11 mag. Mutual eclipse/occultation events that are 0.07-0.15 mag deep indicate a secondary-to-primary mean-diameter ratio of 0.25 +/- 0.02. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2006 CBAT 2006 October 19 (CBET 681) Daniel W. E. Green