Jupiter
Jupiter is the largest representative of our solar system. gas giant, its atmosphere is the seat of violent events, the most emblematic event is the Great Red Spot, a jewel of the cyclone outer solar system. Nevertheless, it has a solid core probably bigger than our planet. Jupiter could be a star, but for lack of material it has never lit ... The fact remains that this planet has a retinue of satellites that are real worlds, many of which would be likely to create conditions favorable to the development of organic matter.
Size and weight
Fifth planet of the solar system and first gaseous planet, is the largest band (142 984km in diameter). It is also the heaviest, its mass being 2 times the total of all other planets in the system (1,900e27 kg)! A comparison of the Earth, Jupiter is a giant: its radius is 12 times greater than that of Earth, its mass is almost 320 times more ... well it would land in 1300 to fill Jupiter!
Observations and discoveries
Due to its impressive size, it is the fourth brightest star of the terrestrial sky behind the Sun, the Moon and Venus (which is much smaller but much closer). Depending on the distance that separates us, its magnitude is situeentre -2.6 and 1.6. Thus, it was discovered there was already a long time, during prehistoric times! In 1610, Galileo discovered even four of the 40 satellites of the giant, using his telescope: Io, Europa, Callisto and Ganymede. This was of importance since it could highlight the non-centrality of the Earth within the solar system, which strongly supported the heliocentric theory of Copernicus. Unfortunately, after having supported this theory, Galileo Galilei, was arrested by the Inquisition: It had to recant his beliefs and was imprisoned for the rest of his life.
Different layers, Different colors
Given the huge amounts of gas, the atmosphere of Jupiter is obviously composed of several layers ... Between the core and the outer layer, lies the bulk of Jupiter, a liquid metallic hydrogen layer. This materialization of hydrogen is possible only a titanic pressure: 4 million bars! Liquid hydrogen is a good conductor, resulting in a very strong magnetic field. The outer layer of the atmosphere, that which is directly observed, is probably composed of ammonium hydrosulfide, and a mixture of ice and water. When we observe Jupiter from Earth, we see yellow orange This is precisely due to the sulfide ammonium and phosphorus from its upper atmosphere. When approaching (as the Galileo probe), there are a range of much wider color corresponding to the height of the cloud into the atmosphere. The colors of the clouds deeper to those on the surface: blue, brown, white and red. Of course, as in the terrestrial sky, in the case of a clear sky on the surface, we see the deeper cloud layers. The bright colors of the clouds are certainly due to chemical reactions between sulfur and other compounds, in fact, the sulfur compounds are spread in a wide variety of colors.
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