The Empire Strikes Back by Ralph McQuarrie
These tremendous aerostatic control vanes regulate the flow of air inside the
reactor shaft. Technologically this enables the citizens to change their
city's position in space, moving it along any plane. The lights in the
background belong to huge loading ports. All cargo flights in the shaft must
be coordinated, for the uncontrolled winds can hurl the best of crafts to
their doom.
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(Last updated at: 980414)