In the ancient human habit of looking moonward and imagining what might be possible there, China now sends its most sophisticated emissary yet — Chang'e-7, named for the goddess of the moon, bound for the coldest and darkest craters at the lunar poles. The mission seeks frozen water, a resource that could transform the moon from a destination into a waystation for deeper human journeys into space. What was once the stuff of myth and scientific curiosity has become a matter of practical necessity, as nations reckon with what it would truly take to live and work beyond Earth.