Electronic Telegram No. 5097
Central Bureau for Astronomical Telegrams
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(5121) NUMAZAWA
     V. Benishek, Belgrade Astronomical Observatory; P. Pravec, Ondrejov
Observatory; V. Chiorny, Kharkiv Observatory; and R. Durkee, Shed of Science
South Observatory, Pontotoc, TX, U.S.A., report that photometric observations
taken with a 0.35-m telescope at the Sopot Observatory in Serbia, a 0.70-m
telescope at the Chuguev station of the Kharkiv Observatory in Ukraine, and
a 0.50-m telescope at the Shed of Science South Observatory during 2021
Oct. 20-Dec. 8 reveal that minor planet (5121) is a binary system with an
orbital period of 17.18 +/- 0.01 hr.  The primary shows a period of 2.6646
+/- 0.0002 hr and has a lightcurve amplitude of 0.13 magnitude at solar
phases 6-9 degrees, suggesting a nearly spheroidal shape.  Mutual
eclipse/occultation events that are 0.07 to 0.14 magnitude deep indicate a
lower limit on the secondary-to-primary mean-diameter ratio of 0.26.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
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                         (C) Copyright 2022 CBAT
2022 February 14                 (CBET 5097)              Daniel W. E. Green