Generalities: it is perhaps the most beautiful planet to be observed because of its rings. Saturn, like Jupiter as well, is predominantly made up of hydrogen and helium, therefore its composition is essentially gaseous. Saturn, like the other external planets, doesn't have a real surface. Going down into the inside of the planet, because of the more and more incresing pressures, a layer of liquid hydrogen is found, which occupies a notable fraction of Saturn’s diameter . Unlike Jupiter, Saturn doesn't have such a mass as to create a layer of metallic hydrogen.  Probably the central nucleus of Saturn is rocky. The ringed planet has a very high rotation speed, since its day lasts a little more than 10 hours. Since it is made up of non rigid material, it shows a strong crushing at the poles, due to the centrifugal strength that tends to expand it to the equator. Its composition enables its rotation speed  not to be  the same at all  latitudes. As it already happens for Jupiter, also Saturn has a rotation period slightly  shorter  at the equator.
Saturn has the characteristic to be the planet of the Solar System with the lowest density (it results less dense than  liquid water). As the other gaseous planets it has a source of inside heat.
The atmosphere on Saturn, which also contains small quantities of methane and ammonia, is one of the most turbulent of the Solar System, showing winds of enormous speed. Unlike Jupiter the storms have small extensions and therefore the atmosphere on Saturn appears more homogeneous and deprived of structures (as the Jupiter red cloud).

Observation: Saturn appears as a star next to magnitude zero in the terrestrial sky (it fluctuates from about -0.3 to 0.8 ). Therefore it appears as a very bright star, not so bright as to be mistakable with other stars. Insofar, the observation of Saturn presupposes the knowledge of the direction in which it is found. Obviously it distinguishes itself from the stars for its firm  not sparkling light. Since Saturn rotates around the Sun in long times, its motion, combined with that of the Earth,  takes it to opposition every 12 months and a half, making it observable for many months a year.

Rings: Saturn’s ring system  is already observable with a small amateur telescope. This is without any doubt  the great attraction of this planet. The rings of Saturn are formed by a great deal of rock and ice  fragments  neatly orbiting around the planet. Their dimensions can go from  millimeters to some hundred meters. Observing the rings some dark zones are observed, where some orbiting material  is not found. These zones separate the different rings, concentric between one another. There are more divisions but the most conspicuous one, already observable with a not too ambitious telescope, is that of Cassini, which takes its name from the famous astronomer living between the second half of the seventeenth century and the first half of the eighteenth century and who was the first  to observe it and to formulate hypotheses on it.
The ring disposition  in comparison to the Earth is not constant, but it varies according to the inclination of Saturn in comparison to the plan of terrestrial revolution. In less favorable periods (as happened in 1995) they are clearly cut, while in more favorable periods they can be observed with a more profitable angling.

Satellites: Saturn’s satellites  are numerous, but almost all of them  have small dimensions (1,000 Km) and they are observable only from the Earth with professional telescopes or even they are not visible (they were discovered by Voyager probes).  An interesting exception is Titano, the biggest satellite of the planet Mercury (5,140 Km of diameter) and the only of the Solar System to be surrounded by a dense atmosphere. This atmosphere, essentially made up of nitrogen and methane, has prevented the shot of photos of the surface from Voyager probes. Among the suggestive hypotheses on Titano there is one  saying that on its surface lakes of liquid methane are present. We will know  certainly more about it in 2004, when the mission Cassini-Huygens  carries a small probe on the surface of this satellite.
 

- Visibility of planets during this month

- Mutual position of Earth and external planets

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