3; &#256;nj&#299;ng (曲安京) solved the mystery. According to his study, only the sexagenary year and day cycle, synodic month and tropical year were involved in the computation of the superior epoch. The observational values of the other astronomical constants such as the anomalistic month, sidereal years and so on were used as a reference and they were adjusted to match the superior epoch. The detail will be explained in the following two sections.</p><br><sect id="computation">Computation of the Super