Electronic Telegram No. 5595
Central Bureau for Astronomical Telegrams
Mailing address:  Hoffman Lab 209; Harvard University;
 20 Oxford St.; Cambridge, MA  02138; U.S.A.
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Prepared using the Tamkin Foundation Computer Network


(22790) 1999 KP_4
     V. Benishek, Belgrade Astronomical Observatory; P. Pravec, P. Kusnirak,
and P. Fatka, Ondrejov Observatory; F. Vachier, Observatoire de Paris;
K. Ergashev and O. Burkhonov, Ulugh Beg Astronomical Institute, Tashkent,
Uzbekistan; J. Oey, Blue Mountains Observatory, Leura, NSW, Australia;
N. Ruocco, Osservatorio Astronomico Nastro Verde, Sorrento, Italy;
R. Goncalves, Linhaceira, Tomar, Portugal; and A. Klotz, J. Berthier, and
P. Thierry, Observatoire des Makes, Reunion, report that photometric
observations taken with a 0.35-m telescope at the Sopot Observatory in Serbia,
a 0.6-m telescope at the Observatoire des Makes, a 0.6-m telescope at Maidanak
Observatory in Uzbekistan, a 0.35-m telescope at the Blue Mountains
Observatory, a 0.35-m telescope at the Osservatorio Astronomico Nastro Verde,
and a 0.35-m telescope at Linhaceira Observatory during June 29-Aug. 2 reveal
that minor planet (22790) is a binary system with an orbital period of 19.29
+/- 0.01 hr.  Mutual eclipse/occultation events that are 0.43- to 0.54-mag
deep indicate a lower limit on the secondary-to-primary mean-diameter ratio of
0.70.  Rotations of the components appear to be synchronous with the orbital
motion, and an amplitude of the combined primary-plus-secondary rotational
light curve is 0.24 mag at solar phases 7-18 deg.


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2025 August 20                   (CBET 5595)              Daniel W. E. Green