Callisto

Callisto is one of Jupiter's largest moons, known for its heavily cratered surface. It’s about the size of the planet Mercury, featuring a mix of ancient, ice-rich terrains and some areas with possible subsurface ocean. Unlike some moons with active volcanism, Callisto’s surface is mostly static, preserved from billions of years of impacts. Its thick icy crust makes it a key point of interest for scientists studying icy worlds and potential habitability beyond Earth. Callisto orbits Jupiter in a stable, distant path, offering insights into the early solar system’s history.