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) light of the Sun before it was tainted by Melkor when he ravished Arien. The name of Narsil, the sword of King Elendil (later reforged for Aragorn as Andúril), contains the elements "nar" and "thil," "fire" and "white light" respectively in Quenya, referring to the Sun and Moon. The Man in the Moon is even described in those writings, as being an old Elf who secretly hid on the island of the Moon, and built a minaret there. This is alluded to further in Tolkien's "Roverandom", in which the Man in the Moon also lives in a minaret. Combined with