摘要
高精度金星重力场的获取,是金星探测的重要内容.本文利用最新的金星地形和重力模型,通过高通滤波后的残差地形（RTM）并在考虑均衡改正的情况下改进了重力的短波成分,最终提出了一个新的金星重力模型VGM2013,该模型赤道分辨率达10 km量级,大大高于现有的金星重力场模型,最终结果是金星表面重力加速度和重力扰动.研究中同时发现金星在Airy-Heiskanen均衡模型下的全球最优补偿深度为30 km,金星地壳的密度可能小于当前认为的2700-2900 k·m.VGM2013模型的结果可为将来的金星探测器定轨和着陆导航提供参考,作为重力计算的先验模型.但由于该模型没有包含短波重力观测信息,不建议直接用于更小尺度的地质和地球物理解释.
Acquisition of the high-resolution gravity field is one of significant objectives in Venus exploration. In this paper, we present a new 3D Venusian gravity field VGM2013 by using the latest topography and gravity models, residual terrain model （RTM） and the Airy-Heiskanen isostatic compensation model. We found the optimal global compensation depth of Venus is about 30 km, and the crust density may be less than 2700 - 2900 kg · m-3, which is generally recognized now. The VGM2013 is the first 10 kin-magnitude Venusian gravity field, which is much better than recent models in resolution, and the ultimate results are the surface gravity accelerations and gravity disturbances. These results are beneficial for Venus spacecrafts＇ orbit determination and landing navigation, and can be utilized as a priori model for Venus gravity field simulation and inversion studies. Given that VGM2013 does not incorporate gravity field observations beyond degree 120, it is not recommended for direct geological and smaller-scale geophysical interpretation.
出处
《地球物理学报》
SCIE
EI
CAS
CSCD
北大核心
2014年第8期2484-2494,共11页
Chinese Journal of Geophysics
基金
国家自然科学基金项目(41174019
41374024)
湖北省自然科学基金重点创新群体项目(2012FFA041)
武汉大学中央高校基本科研业务费专项资金项目(122009
2042014kf0051)
山东省基础地理信息与数字化技术重点实验室开放基金项目(SD080705)资助
