Electronic Telegram No. 5294
Central Bureau for Astronomical Telegrams
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(22569) 1998 HK36
     V. Benishek, Belgrade Astronomical Observatory; P. Pravec, Ondrejov
Observatory; and J. Oey, Blue Mountains Observatory, Leura, NSW, Australia,
report that photometric observations taken with a 0.35-m telescope at the
Sopot Observatory in Serbia and a 0.35-m telescope at the Blue Mountains
Observatory during Aug. 26-Sept. 13 reveal that minor planet (22569) is a
binary system with an orbital period of 15.38 +/- 0.01 hr.  The primary shows
a period of 2.75221 +/- 0.00013 hr and has a lightcurve amplitude of 0.09 mag
at solar phases 4-12 degrees, suggesting a nearly spheroidal shape.  Mutual
eclipse/occultation events that are 0.08 to 0.16 magnitude deep indicate a
lower limit on the secondary-to-primary mean-diameter ratio of 0.28.


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2023 September 28                (CBET 5294)              Daniel W. E. Green