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
East of the Sun and West of the Moon East of the Sun and West of the Moon "East of the Sun and West of the Moon" () is a Norwegian fairy tale. "East of the Sun and West of the Moon" was collected by Peter Christen Asbjørnsen and Jørgen Moe. It is Aarne–Thompson type 425A, the search for the lost husband; other tales of this type include "Black Bull of Norroway", "The King of Love", "The Brown Bear of Norway", "The Daughter of the Skies", "The Enchanted Pig", "The Tale of the Hoodie", "Master Semolina", "The Sprig of Rosemary", "The Enchanted Snake", and "White-Bear-King-Valemon". The Swedish version is