Near-Infrared Spectral Geometric Albedos of Charon and Pluto Constraints
on Charon's Surface Composition

by: Roush, T. L.; Cruikshank, D. P.; Pollack, J. B.; Young, E. F.;
Bartholomew, M. J.

ABSTRACT

The spectral geometric albedos of Charon and Pluto are derived at
near-infrared wavelengths (1.4-2.5 jAm) from measurements obtained in
1987. Comparisons of these to theoretical calculations are used to place
constraints on the identity and relative abundances of surface ices on
Charon. These compari- sons suggest that widespread regions of pure CH4
ice do not occur on Charon and that if CH4 is abundant on Charon then it
is large grained (-5 mm) and is likely mixed at the granular level with
H20 ice, and possibly C02 ice.

Report Number NAS 1.15112307; NASA-TM-112307, 2004.