Where would science fiction be without space mining? From Ellen Ripley in Alien and Dave Lister in Red Dwarf, to Sam Bell in Moon and The Expanse’s Naomi Nagata, the grittier end of interstellar drama would be bereft if it weren’t for overalled engineers and their mineral-processing operations. It’s such an alluring vision that real money has been put toward its realization. Alphabet Inc.’s Larry Page and Eric Schmidt, and Hollywood filmmaker James Cameron (director of the Alien sequel Aliens) all invested in Planetary Resources Inc., which raised venture finance with its mission of mining high-value minerals from asteroids and refining them into metal foams that could be shot back down to Earth. Deep Space Industries Inc., a rival startup, also had bold plans to extract resources from space. Though both companies have now been bought out and their projects put into mothballs, the idea of a space mining industry has refused to die.