Jupiter is the fifth planet of the Solar System. Form leaves from denominated outer or gaseous planets. It receives his name of the Roman God Jupiter (Zeus in Greek mythology).

            One is the planet that offers a greater brightness throughout the year (although Venus can surpass it depending on its phase, like Mars if it is in an advantageous position). It is, in addition, the greater one between planets of the Solar System, with a mass of more than 310 times the terrestrial one, and a diameter 11 times greater.

            Jupiter is a gaseous massive body, formed mainly by hydrogen and helium, devoid of a defined inner surface. Between the atmospheric details they stand out the Great red spot, an enormous anticyclone located in the tropical latitudes of the South hemisphere, the zone and cloud band structure, and the strong zonal wind dynamics with speeds of up to 140 m/s.

            Jupiter is most massive of planets of the Solar System: its mass is equivalent to 2.5 times the sum of the masses of all other together planets. More of a hundred of extrasolar planets they have been discovered with masses similar or superior to the mass of Jupiter. Jupiter also has the speed of faster rotation of planets of the Solar System: tour on its axis in little less than 10 hours. This speed of rotation is deduced from the measures of magnetic field of the planet. The atmosphere is divided in regions with strong zonal winds with periods of rotation that go from 9h 50m 30s in the equatorial zone to 9h 55m 40s in the rest of the planet.

            The planet is known by an enormous meteorological formation, the Great Red Spot, visible by astronomers easily become fond of dice its great size, superior to the one of the Earth. Its atmosphere permanently is covered with clouds that allow to draw up atmospheric dynamics and show a high degree of turbulence.

            Taking as reference the distance to the Sun Jupiter is the sixth planet of the Solar System. Its orbit is located approximately to 5 UA, about 750 million km of the Sun.


5º planet of the Solar System


            The main Jupiter satellites were discovered by Galileo Galilei the 7 of January of 1610, reason for which it is called Galilean satellites sometimes to them. They receive his names of Greek mythology although in the days of Galileo it was denominated to them by Roman numbers depending on his order of proximity to the planet. Originally, Galileo baptized to the satellites like "Mediceos", in honor to Cosme de Médicis, Duke of Florence. The discovery of these satellites constituted a point of flexion in or releases dispute between which they maintained the idea of a geocentric system, that is to say, with the Earth in the center of the universe, and the copernicana (or heliocentric system, that is to say, with the Sun in the center of the Universe), in which it was much more easy to explain the movement and the own existence of the natural Jupiter satellites. The four main satellites are very different to each other. The Ío, most inner, is a world volcanic with a surface in constant renovation and warmed up by effects of tide caused by Jupiter and Europe. Europe, the following satellite, is a frozen world under which the presence of the liquid water oceans is even speculated on and the life presence. Ganímedes, with a diameter of 5268 km, is the greatest satellite of all the Solar System. It is made up of an ice and iron nucleus covered by a rocky mantle. Calixto is characterized being the body that presents/displays greater amount of craters produced by impacts in all the Solar System.

             Jupiter I located it during the month of March of 1982 when it was 14 years old from the Majorcan locality of Inca (Majorca, Spain), for my it was important because during that same month I located to Mars and to Saturn, since they were in conjunction. It had been four years of which I began to be become fond of to Astronomy and therefore, was for my whole a landmark discovering it, for that reason personally is to me still pleasing observing it every year in a different constellation by the zodiaco.


Main natural Jupiter Satellites


Name Diameter (km) Mass (kg) Average orbital radio
radio (km)
Orbital period
Io 3.643,2 8,94×1022 421.600 1.769138 days
Europa 3.122 4,8×1022 671.100 3.551181 days
Ganímedes 5.262 1,48×1023 1.070.400 7.154553 days
Calixto 4.821 1,08×1023 1.882.700 16.68902 days



Orbital characteristics
Average Dist. of the Sun 5.203 UA
Average radio 778.000.000 km
Eccentricity 0,055
Orbital period (sidereal) 11.86 years
Period of rotation 9h.50m.
Orbital speed average 13,06 km/s
Inclination of the axis 3,08°
Number of satellites 60


Physical characteristics
Equatorial diameter 143,800 km
Mass 317,89Tierra
Average density 1,31 g/cm³
Superficial gravity 2.34 Earth
Speed of escape 59,5 km/s
Average Temp. superf.: Day 30.000 ºC
Average Temp. superf.: Night -143 ºC
Atmosphere H2I have



                    In the page Web you can obtain more data of each one of our planets and the dwarf planets defined by the IAU of our Solar System.


Masm © Last update 2006-10-20)