Electronic Telegram No. 861
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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CBAT@CFA.HARVARD.EDU (science)
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(22) KALLIOPE AND (22) KALLIOPE I (LINUS)
     B. Warner, Palmer Divide Observatory, Colorado Springs, CO; and J. L.
Margot, Cornell University, report that photometric CCD observations
(0.5-m Ritchey-Chretien telescope) obtained of this binary main-belt minor
planet (cf. IAUCs 7703, 8177, 8338; CBETs 733, 776) on two nights, Feb.
25-27 UT, revealed a mutual event centered near Feb. 27.24.  Preliminary
estimates yield a V-magnitude drop of 0.04 and an event duration of 1.2
hours.  Mutual events have been predicted by Margot since 2003 on the basis
of the orbital solution published by Margot and Brown (2003, Science 300,
1939), with updates to incorporate additional adaptive-optics data.  The
event occurred within an hour of the prediction.  Further observations of
the mutual events, expected to repeat at half the orbital period of 3.6
days, are strongly encouraged to fully characterize this binary system.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2007 CBAT
2007 February 28                 (CBET 861)               Daniel W. E. Green