April’s moon determines dates of Easter, Passover, Ramadan.
In reaching its monthly moment of maximum fullness on Saturday afternoon, the moon essentially determined the dates of Easter, Passover and the halfway point of Ramadan.
All of those dates depend in one way or another on the lunar calendar. Easter, for example, falls on the Sunday that follows the first full moon after the spring equinox. Obviously, the phases of the moon depend on orbital mechanics and not on whether the atmosphere lets us see our satellite at or near its time of maximum rotundity and brightness.
On the other hand, something may be lost when we must take on faith the descriptions of the lunar movements that have governed so many significant aspects of life for so long. Intending no pun or double meaning, it remained unclear Saturday whether clouds Saturday night or Sunday morning would again shield the full moon from our awed gaze.