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A series of light reflectivity measurements has been made on a variety of samples in a search for materials or surface textures which might reproduce the photometric properties of the lunar surface, particularly the pronounced rise of reflectivity at small phase angles. It has been found that most terrestrial substances, including standard diffusing surfaces, when observed with an instrument of small aperture, show a prominent rise in reflectivity if the direction of observation is within ±5° of the direction of the incident light. Experiments show that the height of the intensity peak entails complex interrelations of the particle size, shape, and optical properties of the reflector. The abrupt increase in the brightness of the lunar surface at zero phase may not be an unusual property of the moon but is one common to most substances. An airplane passenger can easily verify that this phenomenon is a common one by noting the bright zone on the ground around the shadow of the airplane.