Characteristic Research On Lunar Probe Trajectory Based On Spherical Astronomy

Characteristic analysis of lunar probe attitude and trajectory is the premise to attitude control strategy, trajectory selection, and thus on comprehensive lunar exploration. Therefore, a comprehensive analysis of attitude and trajectory characteristics of a probe is necessary before a lunar exploration mission. For instance, satellite solarization in orbit directly affects the solar array energy supply and the design of temperature control system of the probe; and orbital altitude will affect the lunar surface coverage, finally determine the observation results of the probe. Especially, around the moon, orbital altitude will also affect lifetime of the probe. Therefore, a thorough understanding of these features will lay a solid foundation for probe design, orbital optimization and the development of programs for an exploration mission.The apparent position and apparent movement of the observed target are needed in the analysis of space missions, which is only to the geometrical direction. In this thesis, based on spherical astronomy, a series of the lunar orbit are analyzed combing the probe attitudes. This works of this thesis mainly concentrate on the following three aspects:Firstly, how does the shadow of the earth and moon affect probe is analyzed, and two different models to compute lunar eclipse time, which varies with the different solar celestial longitude in a solar year, are investigated for the probe in low-altitude lunar circular and elliptic orbit, and the models are established on orbit dynamics and celestial sphere geometry.Secondly, solarization variations of the lunar probe surface are analyzed when the probe in different attitude and different periods, and the results can be a reference to develop energy supply strategy and thermal control program.Finally, the lunar probe coverage on the lunar surface is analyzed referring to several key parameters of the earth coverage, and some formulas are revised to adapt characteristics of the moon, and some existing inadequate analysis methods are improved to improve the accuracy.