由SGM100i质量分析看SELENE的贡献

月球重力场是研究月球演化和深部构造的基本物理量,也是低轨月球卫星精密定轨的关键。SELENE以高-低卫星跟踪卫星模式历史上首次获得了月球背面重力场直接观测数据。与GLGM-3相比,增加了SELENE跟踪数据的SGM100i在各方面表现出较高的精度:其位系数误差阶方差在15～30阶减小超过10倍,最大达到66倍(15阶);位系数与地形的相关性系数在50～70阶高达0.9,而GLGM-3只有0.6～0.7;基于SGM100i计算的重力异常和月球大地水准面起伏也更好地揭示了月球背面与环形地形相关的重力场特征,从而验证了SELENE 4程Doppler数据对于月球重力场解算的贡献。

Contribution of SELENE for Lunar Gravity Field Recovery from quality analysis of SGM100i

Lunar gravity field is a fundamental physical quantity for the study of the internal structure and the evolution of the Moon,and also plays a key role in precise orbit determination of lunar satellites.Farside gravity field of the Moon is significantly improved from the tracking data of SELENE via a relay subsatellite.SGM100i has been determined from SELENE and historical tracking data which has improved its coefficient sigma error with a factor larger than 10(66 for degree 15) between degree15 to 30 compared with GLGM-3 which is a new lunar gravity model up to degree and order 150.SGM100i has a higher correlation coefficient with topography especially from degree 50 to 70,the value is around 0.9 while for GLGM-3 is 0.6~0.7.According to lunar free-air gravity anomalies and selenoid undulations,SGM100i performs much better than GLGM-3 in revealing the farside gravity ring-shaped features owing to SELENE 4-way Doppler tracking data.