Size and mass: This gives a density of 95/(9)3 * (density)E = 0.1 (density)E. That amounts to 690 kg/m3, less than that of water.

The density suggests that Saturn is mostly made of hydrogen and helium gas, with some water and other molecules that would have come from ``ices'' in the early solar system, plus some molten rock. This is similar to Jupiter.

Why less dense than Jupiter? Saturn has 1/3 the mass of Jupiter (recall that Jupiter's mass is about 320 ME. Thus one expects the gas to be less compressed.

Visible atmosphere: bands but not so colorful as Jupiter.

Saturn's rings

Saturn has a famous ring system. Let's look at the rings. Other planets have rings too. What could they be?

Why rings?
What would be wrong with just an unorganized swarm of particles?

Why not moons?

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Davison E. Soper, Institute of Theoretical Science, University of Oregon, Eugene OR 97403 USA