What is the name of the largest known impact crater on the Moon?

The largest known impact crater on the Moon is the South Pole–Aitken basin. This enormous structure lies on the Moon’s far side, stretches roughly 2,500 kilometers across, and is also the Moon’s deepest recognized basin.

The impact occurred during the Moon’s earliest history, probably about 4.3 billion years ago. The collision excavated an immense depression through the lunar crust and left a basin with unusually low elevations and distinctive concentrations of iron, thorium, and titanium. Its name combines two landmarks at opposite ends: the lunar South Pole and Aitken crater.

Although it is often called a crater, scientists usually describe it as an impact basin because of its extraordinary size and complex structure. It is not the same as Imbrium, Tycho, or Copernicus, all of which are prominent lunar craters but much smaller. China’s Chang’e 4 lander touched down in Von Kármán crater inside the basin in 2019, giving scientists a close look at this ancient region.