The science behind splashdown − an aerospace engineer explains how NASA and SpaceX get spacecraft safely back on Earth

The Orion capsule from NASA's Artemis I mission splashes down. NASA via AP

For about 15 minutes on July 21, 1961, American astronaut Gus Grissom felt at the top of the world – and indeed he was.

Grissom crewed the Liberty Bell 7 mission, a ballistic test flight that launched him through the atmosphere from a rocket. During the test, he sat inside a small capsule and reached a peak of over 100 miles up before splashing down in the Atlantic Ocean.