Ganymede
Ganymede is the largest moon in the solar system, even bigger than the planet Mercury. It is the only moon known to have its own magnetic field.
Ganymede is a giant among moons. It is the largest satellite in our solar system, larger even than the planet Mercury and the dwarf planet Pluto. If it orbited the Sun instead of Jupiter, it would easily be classified as a planet.
A Magnetic Personality
Ganymede is unique because it is the only moon known to generate its own magnetic field internally. This field, likely created by a liquid iron core similar to Earth’s, creates a tiny “magnetosphere” within Jupiter’s much larger one, protecting parts of the moon’s surface from radiation.
Two Terrains
The surface of Ganymede is divided into two distinct types of terrain:
- Dark Terrain: Very old, heavily cratered regions that cover about 40% of the moon.
- Light Terrain: Younger, lighter regions marked by extensive grooves and ridges, likely formed by tectonic activity.
Like Europa, Ganymede is thought to have a subsurface ocean of salt water, sandwiched between layers of ice deep below the surface.