This charming cover art, dating from 1959, shows levitating humanoids not unlike the famed Hopkinsville goblins, who made their dramatic appearance just four years earlier.
Note the conspicuously Martian-looking terrain, a staple of 1950s science fiction. Somehow the notion of a desert planet, bereft of recognizably human structures, speaks to our innate sense of the "other."
Related: The Deep Politics of Hollywood: Close Encounters with the Pentagon.
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