Note 537 — Chapter XVIII · BABYLON

A comparison of the lunar periods as given by Babylonian and by modern astronomers will show how exact were the calculations of the observers of ancient Chaldea.

Periods as calculated by Babylonian astronomers:

Mean sidereal month 27 days, 7 hours, 43’ 14″

Mean synodic month 29 days, 12 hours, 44’ 31.3″

Mean draconitic month 27 days, 5 hours, 5’ 35.8″

Mean anomalistic month 27 days, 13 hours, 18’ 34.9″

Periods as calculated by modern astronomers:

Mean sidereal month 27 days, 7 hours, 43’ 11.5″

Mean synodic month 29 days, 12 hours, 44’ 2.9″

Mean draconitic month 27 days, 5 hours, 5’ 36″

Mean anomalistic month 27 days, 13 hours, 18’ 39.3″

From the foregoing figures it is seen that the maximum difference of time, as given by ancient and modern observers, is less than a half minute; the minimum one-fifth of a second! See Kugler’s Die Babylonische Mondrechnung, pp. 24, 40, 46.