Natural satellites — from volcanic Io to ocean-world Europa.
Earth's only natural satellite, about 384,400 km away on average. It stabilises Earth's axial tilt and drives ocean tides.
Source: NASA Moon facts
Jupiter's volcanic moon — the most volcanically active body known, resurfaced constantly by sulphur eruptions.
Source: NASA Io overview
An icy Jupiter moon with a global salty ocean beneath its crust — one of the most promising places to search for life.
Source: NASA Europa overview
Saturn's largest moon, with a thick nitrogen atmosphere and lakes of liquid methane and ethane.
Source: NASA Titan overview