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The Winter 2010 issue of The Earth Scientist includes a variety of educational resources, ranging from astronomy to glaciers. Check out the other publications and classroom materials in our online store.
This is a drawing of the evolution of the interior of an icy moon.
Click on image for full size
Image from: The New Solar System

How the Interior of Icy Moons Formed

The drawing shows a possible path in the evolution of the interior of icy moons. As the moons drew material from the nebula around them, bits of heavy, solid material accumulated inside the forming moon, as illustrated in figure A.

Once the moon finished forming, these heavy, solid bits of material fell into the center, as illustrated in figure B. Eventually, the heavy, solid material at the center solidified into a core, as illustrated in figure C.

The ice on the outside of the core gradually changed from warm, slushy material, shown in purple in figure B, to frozen ices of various phases, as shown in figure C.


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