Photometric properties of the Moon: Phase curves at small phase angles (0 – 10°) by clementine images

Abstract

Using Clementine data, the phase curves of the lunar surface were investigated at small phase angles (0° to 10°) by direct comparison with standard phase angle (30°) data. We found the geological type dependence and wavelength dependence of the phase curve. Additionally, we found a negative correlation between the reflectance at standard phase angle 30° and the brightness ratio I( small phase angle) I(30°) . The dependencies on the terrain type and wavelength can be simply approximated by the dependence on the reflectance.