Improved nearside gravity field of the Moon by localizing the power law constraint



[1] The problem associated with the large data gap on the farside of the Moon is addressed for constructing a high-resolution global gravity model. By localizing the power law constraint and making it effective only within the farside and limb regions, we mitigate the undesired power-limiting effect on the nearside. Compared to the solution estimated from Lunar Prospector and other satellite tracking data with the globally-applied power law, the locally-constrained solution shows significant improvement of the nearside gravity estimates. Around the areas dominated by craters in the southern hemisphere of the nearside, the correlation with topography approaches nearly 0.95 and the admittance converges to 100–110 mGal/km up to spherical harmonic degree 130, while the globally-constrained solutions distort starting at degree 90. The proposed analysis can benefit the science and operation of other existing and future planetary missions and enhance the geophysical interpretation of the gravity field.