Saturn would float in a giant bathtub
Saturn would float if you found a big enough bathtub.
Reviewed by the CurioVault curator · 8 October 2026 · Last updated 27 September 2026 · Editorial standards
Saturn would float if you found a big enough bathtub. Saturn's average density is 0.687 grams per cubic centimeter, lower than water's 1.0, making it the only planet less dense than water. It is a gas giant mostly hydrogen and helium, with no solid surface. Cassini data confirmed its puffy interior. In theory it would bob like a beach ball. Jupiter is close at 1.33, but sinks. You would need a bathtub 120,000 km wide. It is a fun physics demo: size does not equal heaviness when you are made of gas.
Sources & Further Reading
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