Electronic Telegram No. 5507
Central Bureau for Astronomical Telegrams
Mailing address:  Hoffman Lab 209; Harvard University;
 20 Oxford St.; Cambridge, MA  02138; U.S.A.
e-mail:  cbatiau@eps.harvard.edu (alternate cbat@iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network


(3220) MURAYAMA
     V. Benishek, Belgrade Astronomical Observatory; P. Pravec, P. Kusnirak,
and P. Fatka, Ondrejov Observatory; R. Durkee, Shed of Science South
Observatory, Pontotoc, TX, U.S.A.; F. Pilcher, Organ Mesa Observatory, Las
Cruces, NM, U.S.A.; K. Ergashev and O. Burkhonov, Ulugh Beg Astronomical
Institute, Tashkent, Uzbekistan; D. Augustin, Anglet, France; R. Behrend,
Geneva Observatory; and R. Goncalves, Linhaceira, Tomar, Portugal, 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, a 0.35-m telescope at the Organ Mesa Observatory, a 0.6-m
telescope at Maidanak Observatory in Uzbekistan, a 0.35-m telescope at
e-EyE Observatory in Spain, and a 0.35-m at the Linhaceira Observatory during
2024 Sept. 17-Dec. 25 reveal that minor planet (3220) is a binary system with
an orbital period of 26.73 +/- 0.08 hr.  The primary shows a period of 4.8592
+/- 0.0007 hr and has a lightcurve amplitude of 0.14 magnitude at solar
phases 3-4 degrees, suggesting a nearly spheroidal shape.  Mutual
eclipse/occultation events that are 0.17 magnitude deep indicate a lower
limit on the secondary-to-primary mean-diameter ratio of 0.41.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
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                         (C) Copyright 2025 CBAT
2025 February 21                 (CBET 5507)              Daniel W. E. Green