Electronic Telegram No. 453
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
CBAT@CFA.HARVARD.EDU (science)
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COMET 73P/SCHWASSMANN-WACHMANN
     Z. Sekanina, Jet Propulsion Laboratory, reports that
fragmentation of this comet is apparently continuing.  His modeling
of the motions of nuclei 'K' and 'S' based on their astrometry from
Mar. 24-25 (MPEC 2006-F33) suggests that they separated from their
common parent fragment only about a month earlier and that both
(but especially 'K') must be very small, boulder-sized objects with
irregular and short-lived activity.  When first detected on Mar.
5-6 and reported as fragment 'K' on MPEC 2006-E32, the two
fragments are found to have been < 1" apart and therefore not
recognized as a pair.  The predicted separations of 'K' from 'S'
and the position angles are as follows (0h TT):  Mar. 31, 13", 255
deg; Apr. 5, 20", 252 deg; 10, 31", 249 deg; 15, 48", 246 deg; 20,
75", 244 deg.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2006 CBAT
2006 March 31                    (CBET 453)               Daniel W. E. Green