Electronic Telegram No. 369 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 (1717) ARLON W. Cooney, J. Gross, and D. Terrell, Sonoita Research Observatory, Sonoita, AZ; R. Stephens, Yucca Valley, CA; P. Pravec and P. Kusnirak, Ondrejov Observatory; R. Durkee, Minneapolis, MN; and A. Galad, Modra Observatory, report that photometric observations obtained during 2005 Dec. 4-2006 Jan. 11 reveal that minor planet (1717) has a lightcurve consisting of two linearly additive components with periods 5.1484 and 18.236 hr (and amplitudes 0.08 and 0.13 mag), respectively. Attenuations due to occultations/eclipses do not appear to be occurring at the present geometry, but further monitoring through the end of the current apparition and at future apparitions (to look for attenuations at different geometries) are needed to confirm the inferred binary nature and determine the relative sizes of the components. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2006 CBAT 2006 January 17 (CBET 369) Daniel W. E. Green