Tidal locking

Tidal locking is when two things in space, like a planet and a moon, become so close that they start to have a really strong gravitational pull on each other. This pull makes the planet and moon always face each other with the same side, just like when you and your friend hold hands and swing your arms together while walking.

In other words, the moon rotates around a planet in the same amount of time it takes to orbit around the planet. This means that we always see the same side of the moon facing us from Earth, and the other side of the moon is always facing away from us.

This happens because when the moon is close to the planet, the planet's gravity pulls on the moon really hard. This can cause the moon to stretch and warp, just like how a squishy ball gets stretched when you squeeze it. As the moon stretches and warps, it creates friction inside the moon. This friction causes the moon's rotation to slow down and eventually stop, so it ends up always facing the planet with the same side.

Overall, tidal locking is when two things in space become locked together because of their strong gravity, causing one object to always face the other object with the same side.