I first saw this when it came out in the theater. Though only 13 at the time, I was an avid reader of "hard science" science fiction stories. The technical gaffes of the film are burned into my memory.
Some of the following may have significant spoilers.
Even as a youngster, I knew the premise is silly. The rocket takes off for a lunar mission, in a cosmos where there is always a gravitational effect on the crew (though loose objects float as in zero gravity) and because of that, the "cabin" (the area with the controls, whatever they called it) was gyrostabalized to maintain the "correct" orientation (so that when they landed, why didn't they land standing on their heads?) and where, at least in near-earth space, the rocket engines had to be running continually -- with propellant combusting away without an oxidizer. When the engines quit, the rocket stopped _dead_ in space, and couldn't start going until a PhD chemist determined it needed at a little oxidizer. This time, the rocket recalled it had momentum, and the next thing our heroes know they're near Mars (even a 13-year-old nerd knew such a minimum-energy trip would take over 200 days).
They land, find the air was breathable (though at the time scientific data revealed that the pressure, even if the atmosphere were pure oxygen, would be too low to do any good). They decide to camp outside the ship, and even build a campfire. They come armed, even though they were supposedly going to the Moon, where firearms wouldn't be needed.
They get a sight of a collapsed civilization, encounter stray martians who look just like people, develop an anti nuclear war philosophy, and those who survive try to get back to the home planet, and die in the attempt by crashing on the Earth! To do that would require such a long orbital period, they'd have died of starvation long before approaching their destination.
The film it preceded, Destination Moon, used real science most effectively (even though their "rescue" with the Oxygen Tank forgot about the moment arm from the tank's center of gravity to the output nozzle). This film showed woeful ignorance of even the most basic science. Only the most technologically illiterate should think of it as a science fiction film: it's on a par with the old Flash Gordon serials where their rocketships took off from their bellies and climbed in spirals, and whose engines were always on.
The story on this one I considered banal, and I can recommend this only as a film to be shown to students for them to pick out technical gaffes.
