The Moonless Planet

George RR Martin does this with the incredibly long winters. And one of the things actually that I love about those books that people don't actually talk about is that it is a moonless planet. At no point does anyone ever say, there's no moon in the sky. But he demonstrates it by having dark nights all the time. If you're paying attention, he never describes a moon and there's nothing lunar related in the language at any point in the world building. You kind of have to accept that.