(2825) CROSBY
D. Pray, Sugarloaf Mountain Observatory, South Deerfield, MA, U.S.A.; P. Pravec, J. Vrastil, and K. Hornoch, Ondrejov Observatory; V. Benishek, Belgrade Astronomical Observatory; W. Cooney, Starry Night Observatory, Columbus, TX, U.S.A.; B. Flanagan and B. Pellerin, Madrona Peak Observatory, Medina, TX, U.S.A.; R. Montaigut and A. Leroy, OPERA Observatory, France; and A. Marchini, R. Papini, and F. Salvaggio, Dipartimento di Scienze Fisiche, Della Terra e Dell’Ambiente, University of Siena, report that photometric observations taken with a 0.50-m telescope at the Sugarloaf Mountain Observatory, a 0.65-m telescope at the Ondrejov Observatory, a 0.35-m telescope at the Sopot Observatory in Serbia, a 0.43-m telescope at the Starry Night Observatory, a 0.6-m telescope at the Madrona Peak Observatory, a 0.20-m telescope at the OPERA Observatory, and a 0.30-m telescope at the Astronomical Observatory of the University of Siena during Feb. 17-27 reveal that minor planet (2825) is a binary system with an orbital period of 14.350 ± 0.005 hr. The primary shows a period of 2.8135 ± 0.0002 hr and has a lightcurve amplitude of 0.08 mag at solar phases 7-12 degrees, suggesting a nearly spheroidal shape. Mutual eclipse/occultation events that are 0.04- to 0.08-magnitude deep indicate a lower limit on the secondary-to-primary mean-diameter ratio of 0.18.
2017 March 9 (CBET 4371) Daniel W. E. Green