Conclusions

After a careful examination of the observational data, we have succeeded in constructing an accurate geometric model of the Moon's motion around the Earth. This model differs somewhat from that of Ptolemy, but is constructed along the same general lines.

Table 3: Comparison of the orbital elements of the Moon determined using the updated Almagest model to the true values of these quantities. (Source: Wikipedia.)

Orbital Element	Model Value	True Value
Sideral Period (days)	27.321	27.322
Eccentricity	0.0548	0.0554
Mean Inclination to Ecliptic ($~^\circ)$	5.146	5.145
Precession Period of Ascending Node (years)	18.6	18.6
Precession Period of Perigee (years)	8.85	8.85