This is a cutaway of the interior of Ganymede.
Click on image for full size
Image from: The New Solar System

Evolution of the Interior of Icy Moons

Ice can change itself into many different forms. The forms are called phases. Phases can be as different as diamond and graphite. As can be seen in these pictures, diamond has a very different size and shape than does that of graphite.

The "phase" of ice plays a very important role in the evolution of the icy satellites. As the temperature rises or falls inside the moon, the ice inside will restructure itself and change shape. Thus the moon itself will change its shape as the moon evolves!

The movie shows how the satellite might evolve as it cools and the ice inside changes form. Some layers within the satellite may entirely disappear, and the satellite itself may change in size because some ice phases take less space than others! Part of the movie shows the water ice phase diagram.


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