Astronauts blast off to explore the moon on Rocketship X-M or "Rocketship eXploration Moon". A spacecraft malfunction and some fuel miscalculations cause them to end up landing on Mars. On Mars, evidence of a once powerful civilization is found. The scientists determined that an atomic war destroyed most of the Martians. Those that survived reverted to a caveman like existence.
Rocketship X-M is a 1950 American black-and-white science fiction film from Lippert Pictures, the first outer space adventure of the post-World War II era. The film was produced and directed by Kurt Neumann and stars Lloyd Bridges, Osa Massen, John Emery, Noah Beery Jr., Hugh O'Brian, and Morris Ankrum.