re: What's the difference between SF rocket ships and real space craft?
Even the nuclear-powered USS Discovery in the 1968 film 2001: A Space Odyssey - famed for its supposed attention to accurate detail - did not have heat radiators because the "wings" would make the ship look less aesthetically appealing.
But the early designs did have the radiators:
http://www.underview.com/2001/artwork.html
The lunar surface was also out of date, but that is another story.
