Electronic Telegram No. 5305
Central Bureau for Astronomical Telegrams
Mailing address:  Hoffman Lab 209; Harvard University;
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Prepared using the Tamkin Foundation Computer Network


(11549) 1992 YY
     V. Benishek, Belgrade Astronomical Observatory; P. Pravec, Ondrejov
Observatory; R. Durkee, Shed of Science South Observatory, Pontotoc, TX,
U.S.A.; and M. Husarik and G. Cervak, Skalnate Pleso Observatory, report that
photometric observations taken with a 0.35-m telescope at the Sopot
Observatory in Serbia, a 0.50-m telescope at the Shed of Science South
Observatory, and a 0.61-m telescope at the Skalnate Pleso Observatory during
Sept. 7 to Oct. 19 reveal that minor planet (11549) is a binary system with
an orbital period of 28.96 +/- 0.02 hr.  The primary shows a period of 2.6703
+/- 0.0003 hr and has a lightcurve amplitude of 0.16 magnitude at solar
phases 7-8 degrees, suggesting a nearly spheroidal shape.  Mutual eclipse/
occultation events that are 0.08 magnitude deep indicate a lower limit on the
secondary-to-primary mean-diameter ratio of 0.28.


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2023 October 27                  (CBET 5305)              Daniel W. E. Green