Cutaway of the moon Ganymede

This is an illustration of the interior of Jupiter's largest moon Ganymede. It is based on theoretical models, in-situ observations by NASA's Galileo orbiter, and NASA/ESA Hubble Space Telescope observations of the moon's magnetosphere, which allows for a probe of the moon's interior. The cake-layering of the moon shows that ices and a saline ocean dominate the outer layers. A denser rock mantle lies deeper in the moon, and finally an iron core beneath that.

Links:

• NASA press release
• Artist's illustration of aurorae and Ganymede
• Hubble observation of aurorae on Ganymede
• Ganymede's magnetic field
• Plot of the rocking of Ganymede's magnetic field