Tide half a day) varies in a two-week cycle. Approximately twice a month, around new moon and full moon when the Sun, Moon, and Earth form a line (a configuration known as a syzygy), the tidal force due to the Sun reinforces that due to the Moon. The tide's range is then at its maximum; this is called the spring tide. It is not named after the season, but, like that word, derives from the meaning "jump, burst forth, rise", as in a natural spring. When the Moon is at first quarter or third quarter, the Sun and Moon are separated
Ecclesiastical full moon a transliteration of the Aramaic word meaning Passover. The date of Easter is determined as the first Sunday after the "paschal full moon" falling on or after March 21 (the ecclesiastical fixed date for the Spring Equinox; the actual Equinox can fall on March 19, 20 or 21). This "full moon" does not currently correspond directly to any astronomical event, but is instead the 14th day of a lunar month, determined from tables. It may differ from the date of the actual full moon by up to two days. The use of tables instead of actual observations of the full