Abstract:

The retrieval of the lunar regolith thickness is one of the important missions of our lunar exploration. To get the lunar regolith thickness, the surface effective reflectivity is one of the essentially influential factors. In the previous regolith thickness study, the smooth surface reflectivity model is employed and the calculated horizontal and vertical reflectivity is 0.063 and 0028, respectively, for the whole moon surface on the condition that the view angle is 30°. However, the moon surface is rather rough, and the proper reflectivity model is constructed essentially for the rough surface. Therefore,according to the spatial resolution of the microwave radiometer data (56 km×56 km in 3 GHz channel) onboard the ChangE-1 lunar satellite, the surface roughness model is constructed with the corresponding laser altimeter data(total number, 8×8). Then the effective reflectivity of the lunar surface is calculated based on the Q/H model. The distributions of vertical and horizontal effective reflectivity for rough lunar surface are also presented assumed that the view angle is 30°. The results indicate that the lunar surface roughness has great influence on its effective reflectivity. The surface roughness greatly decreases the horizontal polarized reflectivity, in some place down to 0.050, and increases the vertical polarized one, in some place up to 0.040.

Key words: ChangE-1 lunar orbiter, laser altimeter data, rough surface, effective reflectivity, Q/H model