Surface Compositions of the Satellites of Saturn from Infrared Photometry

JHKL photometry (1.2-3.5 microns) of Rhea, Dione, Tethys, and the high-albedo side of Iapetus reveals broadband spectral signatures essentially identical to those of the water-ice-covered surfaces of Ganymede and the rings of Saturn, although significantly different from either the surface of Europa or laboratory measurements of pure water ice. The dark side of Iapetus has more neutral infrared colors, indicative of a nonicy surface.