Hey how come a great and all powerful planet killer like the Death Star in the Star Wars movie New Hope had to wait for a plant (Yavin) to get out of the way so it could destroy it's moon (yavin 4) that held the secret rebel base. If it was the moon of Yavin then it's orbit was around the planet, destroy the planet the moon would go spinning off into oblivion. There ends the movie and those stinking dirty rebels are eliminated, order restored to the empire and on to conquer bigger and better things.
