Electronic Telegram No. 5123
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


(4528) BERG
     V. Benishek, Belgrade Astronomical Observatory; P. Pravec, Ondrejov
Observatory; G. Scarfi, Iota Scorpii Observatory, La Spezia, Italy; A.
Coffano, W. Marinello, G. Pizzetti, and A. Soffiantini, Osservatorio Serafino
Zani, Lumezzane, Italy; A. Marchini and R. Papini, Dipartimento di Scienze
Fisiche, Della Terra e Dell'Ambiente, University of Siena; P. Bacci, M.
Maestripieri, R. Bacci, and L. Franco, Astronomical Observatory, San Marcello
Pistoiese, Italy; R. Durkee, Shed of Science South Observatory, Pontotoc, TX,
U.S.A.; R. Goncalves, Linhaceira, Tomar, Portugal; N. Montigiani and M.
Mannucci, Osservatorio Astronomico Margherita Hack, Firenze, Italy; G. Baj,
M57 Observatory, Saltrio, Italy; and N. Ruocco, Osservatorio Astronomico
Nastro Verde, Sorrento, Italy, report that photometric observations taken with
a 0.35-m telescope at the Sopot Observatory in Serbia, a 0.40-m telescope at
the Iota Scorpii Observatory, a 0.40-m telescope at the Lumezzane Observatory,
a 0.30-m telescope at the Astronomical Observatory of the University of Siena,
a 0.60-m telescope at the San Marcello Pistoiese Observatory, a 0.50-m
telescope at the Shed of Science South Observatory, a 0.35-m telescope at the
Linhaceira Observatory, a 0.25-m telescope at the Osservatorio Astronomico
Margherita Hack, a 0.35-m telescope at the M57 Observatory, and a 0.35-m
telescope at the Osservatorio Astronomico Nastro Verde during Feb. 2-May 7
reveal that minor planet (4528) is a binary system with an orbital period of
35.02 +/- 0.02 hr.  The primary shows a period of 3.5627 +/- 0.0001 hr and has
a lightcurve amplitude of 0.23 magnitude at solar phases 1-4 degrees.  Mutual
eclipse/occultation events that are 0.06 to 0.12 magnitude deep indicate a
lower limit on the secondary-to-primary mean-diameter ratio of 0.3.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2022 CBAT
2022 May 14                      (CBET 5123)              Daniel W. E. Green