It was a joke between the actor and director in the first movie, when they didn't know there would be more movies. It was sort of spoofing Shatner, with the long pauses. There is a scene in the second movie when the Professor does his usual long pauses between words, while he's on the telephone, and the person on the other end asks if he's still there, totally mocking the character trait. The same actor, Josh Craig, plays the Professor (Monster of Phantom Lake, It Came From Another World) who becomes the Director of Rocket Command (Cave Women on Mars, Destination: Outer Space), as well as that character's son, Captain Jackson in Cave Women and Destination. It's toned down considerably for the Captain character, but still just as funny.