Limb darkening of meteorites and asteroids

The limb darkening at small phase angles of several materials believed to be analogs of those found on the surfaces of asteroids and other related objects such as Phobos and Deimos is investigated. The materials include three carbonaceous chondrites, one ordinary chondrite, and a steel powder. The wavelength dependence of the limb darkening at visible and near-IR wavelengths is examined. The effects of surface roughness on limb-darkening parameters, and hence on measured geometric albedos, are estimated, and the implications for spherical and ellipsoidal asteroids are discussed.