Saturn is considered as the second largest planet in the entire solar system. It is the sixth planet from the Son and is classified as a Gas Giant.
It is composed entirely of Hydrogen Gas and also has small quantities of helium and trace elements. The interior of Saturn is composed of a small core of rock and ice which is surrounded by a thick layer of metallic hydrogen and an outer layer composed entirely of gas.
The planet Saturn has not been explored by humans from Earth. However, a number of unmanned missions or fly by missions have been sent to explore more about this planet. Pioneer 11 was the first mission that visited within 20,000 km of the planet in 1979.
Voyager 1 probe made the second visit in 1980. It was in fact a flyby. In a simple manner a number of other flyby's have also explored the planet.