月球重力场对绕月低轨卫星的长期影响

从解析形式出发,利用月球重力场模型JGL165P1,分析了月球重力场(带谐项)对绕月低轨卫星的长期影响。为了减少计算误差,保证计算精度,在分析解中使用循环公式来计算倾角函数。结果指出对于一个高度为100km的极月轨道卫星,冻结轨道存在的可能性不大,但是当轨道倾角在i=90°附近或者高度再高一些,则有可能存在冻结轨道;对于100km高的初始圆轨道,卫星在无控的情况下半年内将会坠落到月球表面,如果高度增加到200km,则不进行轨道控制也不会坠落到月面上。利用仿真软件GEODYN解算出来的结果证实了上述结论。

LONG-TERM EFFECTS OF LUNAR GRAVITY ON LOW LUNAR ORBIT

In this paper, the long-term effects of lunar gravity ( zonal terms) on low lunar orbit are investigated. The analytical solution are applied to high degree and order lunar gravity field model (JGL165P1). To decrease the computing errors, using the recurrence formulas to calculate inclination functions. The results show that it is not possible to exist for a polar frozen orbit at 100km altitude; however, frozen orbits are possible at higher altitude or inclination around 90 degrees. Results for period orbits show that the eccentricity grows too large before completing a period for a initial polar orbit at 100km altitude. For a initial polar orbit at 200km altitude, the satellite will complete the period. The results are validated by the numerical calculation using the software GEODYN.