首先回顾了火星重力场探测的历史、各有关探测器的轨道特征和获取的资料情况,特别对最成功的MGS项目的情况作了详细介绍.然后对确定火星重力场模型过程中的有关问题作了介绍,包括动力学模型、三体摄动问题、太阳光压和大气阻力模型等.重点介绍了其中的先验条件和求解重力场的算法,后者主要介绍GSFC采用的最小二乘法和先验约束方法及其数据定权和误差校准的经验.文中还对火星重力场与地形学进行了比较分析,并对火星重力场时变性的探测与研究作了重点讨论.最后对火星重力场探测中存在的主要问题作了详细讨论,并展望了我国第一颗火星探测器“萤火一号”对火星重力场研究的可能贡献.%The detecting history of the Mars gravity field, obtained data from various spacecrafts around the Mars and their orbital characteristics are reviewed in this paper; in particular the Mars Global Surveyor (MGS) mission, the most successful mission for the Mars gravity field so far, is described. The related issues in the determination of the Mars gravity field model are introduced. These include the dynamic model, three-body perturbation problem, the solar radiation pressure model, and atmospheric drag model. The issues on a-prior constraint, and the algorithms of solving the gravity field coefficients are introduced in detail, including the methods of improved least square and a-prior constraint used by GSFC as well as their experience in weighting and error validation. The results of the Mars gravity field are further discussed, by comparing the Mars gravity field and the topography. The attempts to detect and study the time variation of the Mars gravity field are also described. Finally, some problems in the determination of the Mars gravity field are discussed. The planned first Chinese Mars mission-"YinHuo-1" (YH-1) satellite, though failed at the time of completion of the paper, is briefly introduced with emphasis on its contribution for the study of the Mars gravity field.
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