What is the largest moon in the solar system?

The largest moon in the solar system is Ganymede, which orbits the planet Jupiter. It is even bigger than the planet Mercury! Ganymede has a diameter of about 5,268 kilometers. It’s made of rock and ice, and scientists believe it might have an ocean deep under its surface. Ganymede also has its own magnetic field, which is rare for a moon. The Galileo spacecraft and later missions like Juno have given us detailed pictures of it. Studying Ganymede helps scientists learn more about how planets and moons form and change over time.