Director Ib Melchior was given just 9 days to shoot the film, on a budget of $200,000.
The "Cinemagic" process, used for all scenes on the surface of Mars, was the result of an attempt by producer Norman Maurer to turn live-action footage directly into hand-drawn animation - or to simulate that. This would enable hand-drawn backgrounds to look as real (or as unreal) as the live action footage. It didn't have that effect here, of course. See The Three Stooges in Orbit for Maurer's second (and failed) attempt at the same process.
The 40-foot alien monster was actually a marionette about 15 inches high. It was essentially a combination of a rat, bat, spider, and crab.
The alien monster is the same one featured on the cover of the album "Walk Among Us" (1982) by The Misfits.