Electronic Telegram No. 1716 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 (4607) SEILANDFARM D. Pray, Carbuncle Observatory, W. Brookfield, MA, U.S.A.; P. Kusnirak and P. Pravec, Ondrejov Observatory; J. Gross, W. Cooney, and D. Terrell, Sonoita Research Observatory, Sonoita, AZ; and R. Durkee, Minneapolis, MN, report that photometric observations obtained during Jan. 17-Feb. 25 reveal that minor planet (4607) is a binary system with an orbital period of 31.63 +/- 0.02 hr. The primary shows a period of 3.9683 +/- 0.0001 hr, and it has a lightcurve amplitude of 0.15 mag, suggesting a nearly spheroidal shape. Mutual eclipse/occultation events indicate a lower limit on secondary-to- primary mean-diameter ratio of 0.29. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2009 CBAT 2009 March 11 (CBET 1716) Daniel W. E. Green