The weight of an aircraft is distributed all along the aircraft. The fuselage, along with the passengers and cargo, contribute a significant portion of the weight of an aircraft. The center of gravity of the aircraft is the average location of the weight and it is usually located inside the fuselage.
Saturn's rings were discovered in 1610 by Galileo Galilei, although he did not see enough detail to know what they were. In 2004, the Cassini spacecraft began capturing unprecedented images of Saturn's atmosphere and the complex structure of its rings and moons. It is hypothesized that the rings formed when Saturn swallowed one of its moons.
He was followed by Cassini, who in 1675 observed that there was a major division in the ring, now called the Cassini Division. This meant that there were at least two rings surrounding Saturn. Today we know that Saturn is surrounded by a huge network of rings, called a ring system, each with unique properties. New information from high powered telescopes (like the Hubble Space Telescope) and spacecraft (like Voyager 1 and 2) have added to our understanding of the rings.