  Approach images taken by the LORRI imaging system during the New Horizons
spacecraft encounter have been used to determine the mean radii and shapes of
Pluto and Charon. The primary observations are limb locations derived using
three independent approaches. The resulting mean radii of Pluto and Charon are
1188.3 +/- 1.6 km and 606.0 +/- 1.0 km, respectively (2-sigma). The
corresponding densities are 1854 +/- 11 kg m-3 and 1701 +/- 33 kg m-3
(2-sigma). The Charon radius value is consistent with previous Earth-based
occultation estimates. The Pluto radius estimate is consistent with solar
occultation measurements performed by the ALICE and Fine Sun Sensor instruments
on New Horizons. Neither Pluto nor Charon show any evidence for
tidal/rotational distortions; upper bounds on the oblateness are <0.6% and
<0.5%, respectively.
