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This is a composite image of the small moons of Saturn.
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NASA

The Composition of Small Moons

The small moons are so called because they are too small to see. That means it is hard to tell what they are made of.

What can be seen of them may suggest that they are made of rock because they are covered with craters as if they were very hard. When the Voyager missions flew by some the moons, however, they took measurements that showed that the inside is also made of ice. So most of these moons must be made out of ice, just as the icy moons are.

The fact that they are small and icy suggests a certain path for their evolution.

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