The Moon's Biggest Crater Was Carved by a North-to-South Strike

The Moon's South Pole-Aitken basin is over 2,000 km wide and about 8 km deep — the largest, oldest crater we know of.

New simulations show a 260-km-wide body hit from north to south at a shallow angle around 4.25 billion years ago.

The strike flung deep mantle rock in a butterfly-shaped spray — about 550 km downrange, 650 km sideways, none uprange.

Lunar mantle could sit as little as 350 m deep near the Artemis landing zone, up to about 3 km thick in places.

NASA's Artemis III, targeting 2028, may scoop up mantle samples without deep drilling.