Saturn has over 60 moons, with Titan being the largest and only one with an atmosphere. It is composed primarily of hydrogen and helium gases and has a low density that allows it to float on water. Saturn spins rapidly, taking just over 10 hours to rotate and 29.5 years to revolve around the sun, and has four distinct seasons with winds that can reach 2000 km/hr. Its iconic rings are made of ice and rock particles about 1 km thick.