Wavelength Dependence of Polarization. XIX. Comparison of the Lunar Surface with Laboratory Samples

Photoelectric polarimetry at several wavelength bands between 0.32 and 0.56 of samples of "pure" mare and terra and of lavas and chemicals are presented. The lunar particles are somewhat translucent, rather opaque. The wavelength dependence of the polarization of the moon, and by comparison, of Mercury, Mars, and the asteroids is produced by the decrease in translucency of the particles with decreasing wavelength. The maria show relatively higher polarization at short wavelengths than the terrae, suggesting either a greater absorption coefficient or larger particle sizes than on the terrae.