In this chapter we investigate complexities of Moon’s motion [11], [49], [53]. The perturbing body is
Sun itself; the magnitude of the perturbing force is thus relatively large. Here, we can no longer use
the averaging principle (its error would skew some of our results by as much as a factor of two), thus,
the time-dependent version of our formulas will be occasionally required. Traditionally, this problem has
always been considered a benchmark for any new technique.
