Le site de vulgarisation scientifique de l’Université de Liège. ULg, Université de Liège
Tidal locking

A situation in which a satellite spins on its axis in the same period of time as it orbits its host. This is the case of the Moon in relation to the Earth. A tidally locked planet, for example, will always show the same face to its star. It will therefore have a permanent day and night side. 

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