To illustrate this point, I'd like to show you three screen grabs from the movie:
So there they are, sitting in a tin can, hurtling toward the Earth. They're returning from Mars -- and of course they're completely unaware that a monster is on board. Now, see, the most important thing you can do when dealing with a monster in space is smoke a cigarette. They had tall lockers filled to the brim with cartons of cigarettes, and people were lighting up throughout the movie. I guess they had a good exhaust system.
Since this film was made in the 1950s, a lot of time was spent lighting women's cigarettes -- which the hapless females were able to enjoy when they weren't serving coffee to the menfolk. Or preparing dinner. Or flirting. Or screaming.
But at some point, you must deal with the monster. Cigarettes alone won't do the trick. So what did they do in their precarious tin-can spaceship? They set off tons of grenades, of course. You wouldn't believe how many grenades they exploded, with nary a care about whether they were near a side wall of the ship.
That's what I love about early sci-fi: the lack of critical thinking -- or any thinking at all. Whenever the world gets me down, I haul out one of these old sci-fi films and laugh my troubles away. Works every time.
That is all. Carry on with your day.