嫦娥二号再拓展试验测定轨精度研究

基于＂嫦娥二号＂卫星再拓展试验的设计轨道,研究各种摄动力对轨道确定精度的影响,得出的结论是：若要达到km量级的轨道确定精度,必须考虑除天王星和海王星之外所有大行星以及日月的质点引力。文章进一步利用数值分析法研究再拓展任务的轨道确定精度,分析结果表明：基于目前的测控条件,使用30 d以上的测轨弧段可以得到稳定可靠的轨道解,而短弧（小于20 d）稳定轨道的获取需要VLBI（甚长基线干涉）测轨数据支持;当＂嫦娥二号＂距离地球700万km时,测控精度可优于30 km;虽然每天测轨弧段的增加可以改善轨道精度,但是当增加到8 h以上时,定轨精度将不再有明显改善。

Orbit Determination Analysis for CE-2 Second Extended Mission

The impact of perturbations on orbit determination accuracy is studied based on the designed orbit during the second extended experiment mission of CE-2(Chang’E-2) satellite.The conclusion is that mass points of the sun,the moon and all major planets except the Uranus and Neptune should be taken into consideration to obtain km-level orbit determination accuracy.The orbit determination accuracy of the second extended experiment mission is studied further with numerical analysis method and the results show that a stable orbit solution can be got with tracking data of an arc of more than 30 days.VLBI(Very Long Baseline Interferometry) tracking data is required to get a stable orbit solution for an arch shorter than 20 days.An orbit accuracy better than 30 km can be got when CE-2 is 7 million km away from the earth.While the increase of daily tracking duration increases orbit accuracy,no significant improvement will be seen when the tracking arc is over 8 hours.