Jupiter is the largest planet in our solar system having a mass more than twice that of all the other planets together, rotates around its axis faster than any other planet, because its rotation is less than 10 hours.
On the visible surface are well evident cloud formations in the form of elongated bands, below of which are predominantly liquid hydrogen and helium.
Jupiter is one of the most interesting planets for amateur astronomers, since it is brighter than the planet Venus after Mars, though sometimes slightly exceeds it, and it is so great that it is visible in binoculars round his record, but with a small telescope you can observe the most conspicuous cloud formations that are the North and South Equatorial Bands, dark, on opposite sides of the bright Equatorial Zone.
In tools of opening over 75 mm are the main internal structures to the clouds whose motion can be appreciated with an observation of at least ten minutes, while already in small tools is possible to detect the crushing of the disk of Jupiter, whose equatorial diameter is over 9000 km greater than that polar due to the rapid rotation. Jupiter sees the brightest and largest when it is the opposition that occurs every 13 months, then only 40 magnifications are enough to make it look as big as the moon.
The main Jovian satellites, Io, Europa, Ganymede and CALLLISTO, were observed for the first time in 1610 by Galileo Galilei, and therefore are called the Galilean moons.
In a small telescope or binoculars to look like faint stars aligned along the plane of the planet, sometimes one or more satellites can not be seen as passing the planet is drowning in its light and when it is hidden behind it.
In addition to the above satellites have satellites children: Leda, Himalia, Lysithea, Elara, Ananke, Carme, Pasiphae and Sinope.
Jupiter is surrounded by an atmosphere of high cloud about 1000 km, the clouds which are of different composition, and are formed at various levels depending on the temperature and pressure, that increase going in depth.
Under the clouds do not exist a solid surface, instead hydrogen and helium are maintained in liquid form to the high pressure resulting from the large gravitational force of the planet: very deep where the liquid hydrogen behaves as a molten metal, the convection originates an intense magnetic field that makes you feel millions of miles into space, while the center of Jupiter is composed of a nucleus probably rocky.
The 16 satellites of Jupiter are classified into three groups: the eight innermost Galilean including four that have a circular orbit on the equatorial plane, the four have intermediate elliptical orbit inclined at 25 ° / 30 ° on the equator and with four outer retrograde elliptical orbits, that is, from east to west.
Jupiter is also surrounded by a thin ring of dust which extends over 100000 kilometers.
Jupiter has always been recognized as the symbolic representative of the deity who created the world and men, beside the fact images of Zeus, and astrology, presides over the shopkeepers, the material and spiritual wealth, kings, and how the zodiac signs Pisces and Sagittarius.