tidal-locking

The Moon's far side isn't dark — it just faces away from Earth. Tidal locking, crater asymmetry, Chang'e missions, and what's really there.

Tidal locking happens when a body's rotation period equals its orbital period, so one face always points at its partner. The Moon is locked to Earth, Mercury is caught in a 3:2 resonance instead, and many planets around red dwarf stars are probably locked to their stars.

Tidal locking occurs when a body's rotation period equals its orbital period, so one hemisphere permanently faces its partner. The Moon is locked to Earth, which is why we always see the same face, and the same effect probably shapes planets around red dwarf stars.

Earth spins at 1,674 km/h at the equator. If it suddenly stopped, supersonic winds would devastate the surface. If it slowed gradually, the consequences are still severe — a 6-month day, ocean redistribution, and a collapsing magnetic field.