This was the first feature made at the Studio City Complex in Miami, Florida.
The mission liftoff is depicted by stock NASA footage of three different rocket takeoffs; SA-201, SA-202, and a third, unidentified Atlas rocket. Several rocket scenes of the landing and second takeoff make use of the Atlas rocket footage.
Darren McGavin would return to Mars as an astronaut in The Martian Chronicles eleven years later.
Co-Star Nick Adams died in February, 1968, almost six months before the completed film was released that July.