1. A highly accurate astronomical system for the measurement of time based on the period of Earth s orbit, but in practice relying on lunar observations and an accurate lunar ephemeris.
历书时：一套计量时间的极端精确的天文学系统，它通常基于地球的公转轨道
2. A fast design method for the lunar satellite transfer trajectory is presented by combining patched conic technique and ephemeris.
提出了一种将圆锥曲线拼接法与历表相结合，快速设计月球卫星地月转移轨道的方法。