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.
Before the advent of telescopic photography, eight moons of Saturn were discovered by direct observation using optical telescopes. Saturn's largest moon, Titan, was discovered in 1655 by Christiaan Huygens using a 57-millimeter (2.2 in) objective lens on a refracting telescope of his own design. Tethys, Dione, Rhea and Iapetus (the  Sidera Lodoicea ) were discovered between 1671 and 1684 by Giovanni Domenico Cassini.