Additional Data:

Diameter:	139.820 km
Average distance to the sun:	778.510.000 km
The mass of 1 kg weighs on Jupiter:	2.630 g
One year on Jupiter lasts:	11 years 314 days
One day on Jupiter lasts:	9 hours 55 minutes
Temperature on the surface:	-108 °C
Orbital velocity:	13,07 km/s
Orbital inclination:	1,304 °
Orbital excentricity:	0,0489
Weight:	318 earth masses
Density:	1.326 kg/m³
Gravitational accelleration:	24,79 m/s²
Escape velocity:	59,5 km/s
Tilt of the rotational axis:	3,13 °
Number of moons:	92
Number of rings:	3

 

Jupiter is the largest planet in the solar system. Its diameter is 11 times larger than Earth's and it is 318 times heavier than our home planet. Jupiter is one of the gas planets. These planets are usually larger than rocky planets and have an atmosphere that is very different to the one we have on Earth.

The planet Jupiter was named after the supreme Roman god. Even in ancient times, Jupiter was observed by astronomers because of its striking brightness. Even with a simple telescope or binoculars, you can make out the bands in its atmosphere. Similar to rocky planets, gas planets also have a layered structure. Jupiter's interior is thought to contain a rocky core. However, the bulk of the planet's mass is made up of its atmosphere. This consists of 75% hydrogen gas and 25% helium. There is no solid surface on Jupiter, as there is on Earth. The atmosphere at high altitude, as with other planets, is relatively thin. There is little pressure there. The deeper you go into the atmosphere, the more pressure and temperature rise. Under these conditions, the gases are liquefied. Towards the core, metallic hydrogen is even produced under the high pressure. In this process, the gas is compressed in such a way that electrons can jump from one atom to the next. In the upper atmosphere, there are storms with breathtaking speeds. In 1665, physicist Robert Hooke observed a large red spot on Jupiter, which he recognized as a hurricane. This storm rages there to this day. It is so big that the earth would have room in it 2 times. This storm is known as the Great Red Spot.

Jupiter rotates on its axis in just over 9 hours. This makes it the fastest in the solar system. Without a solid surface, however, parts of the planet's atmosphere rotate faster than others. Inside, this ensures that a magnetic field is created, similar to that of rocky planets. Unlike Earth's, Jupiter's magnetic field is stronger than that of any other planet. If it could be seen from Earth, it would be larger than the Moon.

Galileo Galilei discovered with his telescope in 1610 that Jupiter is orbited by four moons. Jupiter and its moons represent a small solar system of their own. In the 17th century, this discovery led the Church to admit that not all celestial bodies revolve around the earth.

In addition to the moons Io, Europa, Ganymede and Callisto, a total of 92 moons have been discovered to date. Many of them are only between 5 – 50 km wide. Ganymede, on the other hand, is larger than the planet Mercury at 5,262 km. Some moons orbit Jupiter in strongly inclined orbits. Some moons even orbit it retrograde, i.e. clockwise. However, most celestial bodies orbit around Jupiter and in the solar system prograde, i.e. counterclockwise. Jupiter, due to its great gravitational pull, has captured some of its moons over time. In 1979, the Voyager 1 spacecraft also detected three thin rings during its flyby of Jupiter.

The moons of Jupiter are named after mythological figures. In 1906, the first asteroid was discovered, located at one of Jupiter's Lagrange points. Asteroids orbiting Lagrange point 4 are called Trojans. They move in the same orbit as Jupiter around the Sun but rush ahead of it by 60°. Hot on their heels are the Greeks – asteroids orbiting Lagrange point 5, 60° behind Jupiter. So far, 8,000 "Trojan" and 4,000 "Greek" asteroids have been discovered.

Jupiter and its moons still raise questions in science. Two of its moons are particularly interesting: the moon Io shows strong tectonic activity on its surface. Its surface has no impact craters because they are very quickly filled by lava. As it orbits Jupiter, the gravitational pulls of the planet and the other large moons tug at it. As a result, its innermost part is kneaded and there is enough heat for volcanoes.

The moon Europa is surrounded by a thick sheet of ice. Similar to Io, it is also kneaded by gravitational forces. However, since there are no volcanoes and no impact craters to be seen, it is assumed that the ice on Europa is constantly being renewed. This could indicate an ocean beneath the ice sheet. Along with Enceladus – a similar moon orbiting Saturn – Europa is considered the best chance in the solar system to discover life that originated independently of Earth.