What is a key characteristic that distinguishes Ganymede among the Galilean Moons?

Answer

It is the only moon known to possess its own magnetic field

Ganymede holds the distinction of being the largest moon in the Solar System and is unique among moons for having its own intrinsic magnetic field.

What is a key characteristic that distinguishes Ganymede among the Galilean Moons?
discoveryGalileoastronomytelescopeMoon