The bases in dating and when should they happen
Easter is the time when Christians celebrate the Resurrection of Christ.According to the gospels he was killed three days before the Resurrection, around the time of the Jewish Passover.
Scores of formulae have been devised to try to reconcile the two as a method of marking time. A century on, 84-year tables were introduced, which were still in use in parts of the British Isles as late as 931.
The commonest date is 19 April though the full cycle of Easter dates only repeats after 5,700,000 years. Astronomers have tried to reconcile the lunar and solar cycles since the time of the ancient Greek stargazer Meton of Athens who came up with the 19-year Metonic cycle.
And the ancient Egyptians knew that the heliacal rising of Sirius was a more accurate predictor of the flooding of the Nile than solar dates were.
And the tidal drag between the Earth and the Moon and Sun, which is affected by melting glaciers and sea-level rise, increases the length of the day and of the month.
Can't we just pluck a fixed date out of the air and agree on it?