Introductory text to the planet Jupiter
Of the Jupiter is one of four gas planets and at the same time the largest planet in the solar system. The upper layers of Jupiter are 99.9% hydrogen and helium. With increasing proximity to the interior of the planet, the chemical elements become liquid due to the increasing pressure. Perhaps the Jupiter's core, which is about the size of the Earth, consists of much heavier elements.
After sun, moon and Venus, Jupiter is the fourth brightest celestial body. In antiquity, the Romans named the planet after the god Jupiter, the most powerful of all gods and guardians of the sky. At that time, they did not yet know that Jupiter would be the largest and most massive planet in the solar system. The mass of 318 earths theoretically fit into Jupiter.
Not recognizable in the illustrations is the Ring of Jupiter. Similar to Saturn, Jupiter also has a ring that can not be found with the naked eye. Collisions between the asteroids and the moons of Jupiter throw dust particles into orbit again and again. The strong magnetic field, as well as the planet's gravitational field, slowly pulls up the dust particles in a spiraling motion. For the attraction of the moons is far less than that of Jupiter.
No planet rotates faster around its own axis than Jupiter. In 9h55min the massive planet makes a complete turn. Jupiter, on the other hand, copes with an orbiting period around the sun in twelve years, making it by far not the planet that needs the longest. Neptune's orbital period lasts 165 years.
The moons of Jupiter
With currently 67 known moons, Jupiter has the most satellites in the solar system. The smallest moons have a diameter of just one kilometer, the largest of just over 5000km. Because of its enormous mass, Jupiter also has the strongest gravitational field in its environment, attracting asteroids into its orbit over the millions or billions of years. Particularly interesting: astronomers suspect liquid water on some Jupiter moons. Potentially, microbial life could be possible there.
Europe (3121km), io (3643km), Callisto (4821km) and Ganymede (5262km) are the four largest moons. Galileo Galilei discovered and described in 1610 as the first the Jupiter satellites. For this reason they are also called Galilean moons.
Europe: about -180 ° C surface temperature; The lunar surface consists of ice, at least 20km in diameter; Below that is probably an ocean of liquid water; Tidal forces, caused by the attraction of Jupiter, move the ice crust.
io: nearest Galilean moon at Jupiter; consists mainly of rock, probably with iron core; -150 ° C surface temperature, but signs of active volcanism with lava of + 1000 ° C and plate tectonics; only a few impact craters on the lunar surface.
Callisto: most of the four moons; The surface consists of a mixture of ice, dust and rock, at about -140 ° C; Below lies a thick layer of ice, which rests on an ocean of liquid water.
Ganymede: at least 3 billion years old and largest Jupiter's moon; The surface consists mainly of ice, at a temperature of -150 ° C; Signs of volcanism in the past; Presumably, this moon also has an ocean of liquid water inside; Low levels of oxygen in the atmosphere.
All Jupiter moons bear names of figures from Greek mythology: Adrastea, Aitne, Amalthea, Ananke, Aoede, Arche, Callirrhoe, Carme, Carpo, Chaldene, Cyllene, Dia, Elara, Erinome, Euanthe, Eukelade, Euporie, Europe, Eurydome, Ganymede , Harpalyke, Hegemone, Helike, Hermippe, Herse, Himalia, Io, Iocaste, Isonoe, Kale, Callistore, Callisto, Kalyke, Kore, Leda, Lysithea, Megaclite, Metis, Memes, Orthosia, Pasiphae, Pasithee, Praxidike, Sinope, Sponde , Taygete, Thebe, Thelxinoe, Themisto and Thyone. All other moons (17) are still waiting for their official naming. The discovery of further, small Jupiter moons is not excluded.
Jupiter - indispensable for the earth?
750 million kilometers separate Jupiter from planet Earth. While the sun's rays reach the earth in just over eight minutes, they take as much as 44 minutes to Jupiter, mind you at the speed of light (300,000,000 m / s). And although both celestial bodies are so far apart, the planet indirectly occupies a protective function for the earth. Between Mars and Jupiter lies an asteroid belt. So far, more than 600,000 objects of different sizes have been identified. By mass, Jupiter stabilizes the trajectories of the asteroids in the asteroid belt, potentially preventing impacts on planets located in the inner solar system (Mercury, Venus, Earth, and Mars). If even the force of attraction of Jupiter prevented even an asteroid from striking the earth, we owe our existence to this planet. The impact of the asteroid impacts on existing ecosystems has been proven by the impact on the Yucatan Peninsula 66 million years ago, which marked the end of the era of dinosaurs.
Climate on Jupiter
With wind speeds of 500 km / h and an average surface temperature of at least -100 ° C, the climate is anything but life-friendly from a human perspective.
Extreme weather on Jupiter can even be observed. The 'Eye of Jupiter' is an anticyclone of gigantic proportions. The cyclone has a diameter of two to three diameters (about 20,000 - 30,000km) and is therefore the largest in the entire solar system. Incidentally, astronomers already observed the weather phenomenon more than 300 years ago.