Orbit Determination Ability Analysis of the GRAIL Gravity Model

The new GRAIL gravity model GRGM660PRIM has advanced in the aspect of resolution and degree when compared with historical lunar gravity field models. In this paper, we present a quantitative analysis of the orbit determination ability of the GRGM660PRIM in orbit prediction and precise orbit determination (POD). In a comparison with the LP50Q and SGM150j models, results show that the GRGM660PRIM is close to the level of the LP150Q and SGM150 in satellite lifetime prediction; in the Apollo 16 subsatellite POD, GRGM660PRIM shows its advantages at high degrees and precision, the residuals RMS of two Doppler decreases from 1.36~1.48 mm/s to 0.722 mm/s, and the three way Doppler residuals RMS decrease from 1.67~1.69 mm/s to 1.2 mm/s;the precision of orbit determination improves significantly. These conclusions can provide a reference for the upcoming Chinese Chang'E-5 mission and further lunar missions.