When, in 1610, Galileo Galilei looked through his telescope towards Saturn; he was convinced that he had detected moons lying close to the planet. It was only 50 years later, when the Dutch astronomer Huygens, equipped with an improved telescope, first interpreted the objects observed by Galilei as an extensive ring system.
The composition and structure of Saturn is similar to that of Jupiter. It consists mainly of hydrogen and helium, although its rocky core is probably larger than that of Jupiter. Saturn's atmosphere consists of 88 percent hydrogen and 11 percent helium. There are further traces of methane, ammonium and other compounds.
Saturn has a diameter of 120,000 kilometers and its mass is 95 times that of the Earth. It is the second largest planet in our solar system It also features an extraordinary high speed of rotation. One day on Saturn is only 10 hours and 40 minutes. Temperatures are around 180┬░ Celsius. Similar to Jupiter, Saturn shows an oblate shape with flattened poles. This is a result of its high rotational speed and comparatively low density, which is only approximately 70% of that of water.
From this we can conclude that Saturn would actually float on water. Its diameter, including the ring system is approximately 960,000 kilometers, which is around two and half times the distance between the Earth and the Moon. Its rings have been named by the letters of the alphabet, in sequence of discovery.
Starting at the inside of the ring system towards the edge, we have the D, C, B, A, F, G and E rings. Today, we know that there are at least 100,000 additional smaller rings. There are several theories on the origin of the ring system. One theory is that its ice and rock debris originates from collisions of moons and asteroids. According to a different theory, former satellites of Saturn broke up into billions of particles as a result of extremely strong gravitational_forces. Due to the high rotational speed and the gravitational_forces, these particles gradually formed rings around the planet.
