Electronic Telegram No. 240
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)
URL http://cfa-www.harvard.edu/iau/cbat.html


S/2005 (2003 UB313) 1
     M. E. Brown, California Institute of Technology, on behalf
of the adaptive-optics team at Keck Observatory, reports
the discovery of a satellite of the transneptunian object
2003 UB313 (cf. IAUC 8577) from six 60-s K'-band exposures taken
on Sept. 10.52 UT with the "Laser Guide Star Adaptive Optics"
system at the Keck II telescope.  The satellite was found to
be 4.43 +/- 0.05 mag fainter than the primary and to be
separated 0".53 +/- 0".01 from the primary in p.a. 275 +/- 1
degrees.  Additional Hubble Space Telescope observations are
planned for November.


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      superseded by text appearing later in the formal IAU Circulars.

                         (C) Copyright 2005 CBAT
2005 October 2                   (CBET 240)               Daniel W. E. Green