Harrison Schmitt, now 90, was on the Apollo 17 mission — the last time humans visited the moon. On Wednesday, NASA's Artemis II mission aims to kickstart a return.

Here's what to know about Artemis II, the first time NASA sent humans to the moon and why some people (ahem, Kim Kardashian) believe it never happened.

This 2009 documentary narrated by actor Peter Cullen relives the 40th Apollo Anniversary and mission to explore the moon.

Earth and the moon may look very different today, but they formed under similar conditions in space. In fact, a dominant hypothesis says that the early Earth was hit by a Mars-sized object, and it was this giant impact that spun off material to form the moon.

The four astronauts making NASA's next lunar leap bear little resemblance to the Apollo era. The Americans who blazed the trail to the Moon more than half a century ago were white men chosen for their military test pilot experience.