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 (Middle-earth) Sun. In the universe of Middle-earth, the Sun is generally regarded as feminine, in recognition of Arien. This gender corresponds with Sól (Sun), the personified in Germanic mythology. The Maia Tilion was chosen to guide the vessel of the Moon. Names of the Moon amongst the Elves included Isil or "The Sheen", a name given to it by the Vanyar; Ithil, the common name for the Moon in Sindarin, as seen in "Minas Ithil" (later Minas Morgul) and the Gondorian province of Ithilien; and Rána, or "The Wayward", a name given to the Moon by the Noldor. A poetic name