A simple and clear method to calculate the averaged motion of the apsis line in the Moon orbit is proposed. The obtained result is for the starry period of the Moon revolution around the Earth or per year. The modern observed value of the latter quantity is per year. In “Principia” Newton derived for the Moon month and per year, that is approximately two times less than the observed values. Contrary to the Newton approach, we use a simple and obvious averaging of the Sun disturbing force for the starry period of the Moon revolution around the Earth. The applicability of the obtained formulae to satellites of other planets and to the planets themselves is argued. Comparing Newton's calculation with our method, we reveal the reason, rather convincing, that brought Newton to an imprecise result.

中文翻译：

---

月球拱顶运动的简单计算

提出了一种简单明了的计算月球轨道近点线平均运动的方法。获得的结果是月球绕地球公转的恒星周期或每年的结果。后者的现代观测值是每年。在牛顿的《原理》中推导出的每月和每年的月球值，大约比观测值小两倍。与牛顿方法相反，我们对月球绕地球公转的恒星周期使用太阳干扰力进行简单而明显的平均。所获得的公式对于其他行星的卫星和行星本身的适用性存在争议。将牛顿的计算与我们的方法进行比较，我们相当有说服力地揭示了导致牛顿得出不精确结果的原因。