All of the necessary technologies required to reach the Moon was first tested during Project Gemini, which comprised of ten missions in the mid-1960s.
| Actor | Role |
|---|---|
 Buzz AldrinSelf | Self |
| MMarc AverbackNarrator | Narrator |
| CCharlie BassettSelf | Self |
 Frank BormanSelf | Self |
| EEugene CernanSelf | Self |
 Charles ConradSelf | Self |
 Gordon CooperSelf | Self |
| RRichard GordonSelf | Self |
 Gus GrissomSelf | Self |
 Jim LovellSelf | Self |
| JJim McDivittSelf | Self |
| WWally SchirraSelf | Self |
| EElliott SeeSelf | Self |
 Thomas StaffordSelf | Self |
 Edward H. White IISelf | Self |