Earth referred to as "moons", after Earth's. The gravitational attraction between Earth and the Moon causes tides on Earth. The same effect on the Moon has led to its tidal locking: its rotation period is the same as the time it takes to orbit Earth. As a result, it always presents the same face to the planet. As the Moon orbits Earth, different parts of its face are illuminated by the Sun, leading to the lunar phases; the dark part of the face is separated from the light part by the solar terminator. Due to their tidal interaction, the Moon recedes
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