In “That Alien, Sound,” the debut feature from writer/director/editor Brando Topp, a young woman named Mika (Mia Danelle) becomes possessed by a soundwave that’s been floating around in outer space.

That now classic tagline (from Alien, one of the greatest science-fiction horror movies ever made) hinges on a big assumption that most of us broadly make: space is empty. And it is—mostly. But there ...