Based on the observation requirement of global change study, the point-by-point method was used to calculate the coverage indicators on the basis of orbit simulation and spherical ground triangulation. Then, a comparison was made among three platforms in space: Geostationary satellite, the Moon and the Earth-Sun L1 point. The result has shown that, though the temporal-spatial coverage from the Moon is only a little larger than that from Geostationary orbit, the moon offers a much better angular coverage, which is of great significance to the multi-angle remote sensing and the observation system to detect the Earth's energy balance.