Binary asteroid discovery IAU announcement

IAU CBET nº4523

(15745) YULIYA
A. Aznar, Observatorio Isaac Aznar, Aras de los Olmos, Spain;
O. Vaduvescu, Isaac Newton Group (ING) and Instituto de Astrofisica de
Canarias (IAC), Spain; T. Wilson, Isaac Newton Group (ING), University
College London (UCL), U.K.; T. Zegmott, Isaac Newton Group (ING),
University of Kent, U.K., and P. Pravec, Ondrejov Observatory, report
that photometric observations taken within the European Near Earth
Asteroids Research (EURONEAR) program with a 1.2-m telescope at the
Mercator Observatory, La Palma, Canary Island, Spain, during
Apr. 26-May 6 reveal that minor planet (15745) is a binary system with
an orbital period of 15.63 +/- 0.02 hr.  The primary shows a period of
3.2486 +/- 0.0003 hr and has a lightcurve amplitude of 0.10 mag at solar
phases 35.1-35.2 degrees, suggesting a nearly spheroidal shape.  Mutual
eclipse/occultation events that are 0.15- to 0.21-magnitude deep indicate
a lower limit on the secondary-to-primary mean-diameter ratio of 0.43.