Saturn would float in water if there were a bathtub large enough.
Why it is true
Despite its gigantic size, Saturn is the only planet in the solar system with an average density lower than that of water, due to its mostly gaseous composition of hydrogen and helium.
Source: NASA
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Related facts
Titan, a moon of Saturn, is the only moon in the Solar System with a thick atmosphere.
Mimas, a moon of Saturn, has a crater so big that it looks like the Death Star from Star Wars.
Enceladus, a moon of Saturn, has water geysers at its south pole.
The interstellar comet 3I/Atlas releases more than five tonnes of water vapour per second.
