We report on Hubble Space Telescope (HST) observations of three Kuiper Belt
Objects (KBOs), discovered in our dedicated ground-based search campaign, that
are candidates for long-range observations from the New Horizons spacecraft:
2011 JY31, 2011 HZ102, and 2013 LU35. Astrometry with HST enables both current
and future critical accuracy improvements for orbit precision, required for
possible New Horizons observations, beyond what can be obtained from the
ground. Photometric colors of all three objects are red, typical of the Cold
Classical dynamical population within which they reside; they are also the
faintest KBOs to have had their colors measured. None are observed to be binary
with HST above separations of ~0.02 arcsec (~700 km at 44 AU) and {\Delta}m
less than or equal to 0.5.Comment: Pages: 11, Figures: 2, Tables: 3, Icarus, available online May 2014
(http://dx.doi.org/10.1016/j.icarus.2014.04.014