Well, since there is hardly anything scientific to be found in Star Wars, it's kind of an exercise in futility, but my theory is because it looks cool.
In my opinion however, the best best best Outer space sci fi still is the vulnerable 2001 a Space Odyssey. Nothing can touch it accuracy, such as no sound in space, etc. That was an accurate movie.
Anyway, Star Wars is still fun. I guess if I want to get closer to accuracy, then I need to go Star Trek, but still, that is a little bogus in cases too.
-S
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