Earth tide Earth tide Earth tide (also known as solid Earth tide, crustal tide, body tide, bodily tide or land tide) is the displacement of the solid earth's surface caused by the gravity of the Moon and Sun. Its main component has meter-level amplitude at periods of about 12 hours and longer. The largest body tide constituents are semi-diurnal, but there are also significant diurnal, semi-annual, and fortnightly contributions. Though the gravitational forcing causing earth tides and ocean tides is the same, the responses are quite different. The larger of the periodic gravitational forces is from the Moon but that of the
Sun and moon allegory Sun and moon allegory The Sun and Moon Allegory is used to image a medieval political theory that was espoused by the Roman Catholic Church and instantiated to some extent in medieval political practice. Finding this imagery in the "Book of Genesis", the Allegory images authentic spiritual authority as the Sun and any and all civil, or political or secular, authority as the Moon. By doing so, it illustrates that the Roman Catholic Pope, as "Supreme Pontiff", "Vicar of Christ", et cetera, and therefore the supreme universal spiritual authority on Earth, is like the Sun that is the one source