Saturn

Saturn is the sixth planet from the Sun and the second largest in the Solar System. Though enormous, it is made mostly of hydrogen and helium, and its average density is lower than that of water. In principle, if you could find a bath large enough to hold it, Saturn would float.^[1] Astronomers have looked for such a bath and report that there isn't one.

Rings

Saturn's rings are made of countless pieces of ice and rock, from tiny grains to chunks the size of houses. They stretch across hundreds of thousands of kilometres, but the main rings are, in most places, only about ten metres to a kilometre thick.^[2] Scaled down to the width of a sheet of paper, they would be thinner than the paper. Saturn is therefore the only planet wearing something that is mostly width.

Seen from Earth the rings tilt at different angles over Saturn's 29-year orbit. Twice in each orbit they line up edge-on and nearly vanish from view, which caused Galileo some confusion and is the only time a planet has appeared to take its rings off.

Moons

Saturn has well over a hundred known moons, more than any other planet, and the number keeps going up as astronomers find small ones. Its largest moon, Titan, is bigger than the planet Mercury and has lakes, rain and rivers, though they are made of liquid methane and ethane, not water. It is the only other place known where rain falls into lakes, and it is the wrong kind.

See also

• Venus – another planet with an odd record
• Circle – the shape of its rings, from above
• Rain – Titan's is methane
• Jupiter – the bigger one
• Neptune – another giant, further out

References

1. Bath, B. (1998). It Would Float. Orbit Press.
2. Ringwidth, R. (2005). “Thinner Than Paper”. Planetary Rings Review 10: 1.
3. Titan, T. (2012). The Wrong Kind of Rain. Moon Books.