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The first planet in the outer solar system (beyond the asteroid belt), Jupiter is the fourth in our series on planets.
Location
The planet Jupiter is located in the external solar system. It is indeed 778.6 million kilometers from our star, or 5.20 AU (Earth is 1 AU from the Sun). With a diameter of 142,984 km and a mass of 318 Earth, it is the largest planet in our system. It could thus contain more than 1,300 Earths.
The gravitational pull of this huge planet is such that it attracts a large number of orbiting satellites (67 known to date) and are four the size of a planet. This set is called the Jovian System.
Discovery
Visible to the naked eye, Jupiter has been known since Antiquity, but precise observations began in the 17th century. Thus, it was Galileo who, in 1610, discovered the first four satellites thanks to his telescope. In the 1660s, astronomers began to describe the planet with its different tasks and colored bands. The famous Great Red Spot was discovered by Robert Hooke and Jean-Dominique Cassini. This spot is in fact a huge high pressure storm that has lasted for over 300 years. About 17,000 km wide, with winds of over 700 km / h, this depression is larger than Earth.
Type and composition
Jupiter is one of the four gas planets in our solar system (Jupiter, Saturn, Uranus and Neptune). That is to say, it is composed of 86% hydrogen and 13% helium. There is undoubtedly a solid nucleus in the center of Jupiter (the size of the Earth) which would be surrounded by liquid hydrogen (78% of the radius of the planet) then by a thin layer of gaseous hydrogen, making this star an essentially liquid planet. Its atmosphere, constantly traversed by strong winds, is made up of clouds of water and ice.
Did you know ?
Jupiter has, like Saturn and Uranus, a system of very fine rings invisible from Earth. They were only discovered in 1979 by the Voyager 1 probe. Composed of debris, these rings are fleeting. Indeed, in the long term, this dust will eventually agglomerate or be attracted to the planet and vaporize in the atmosphere.
Jupiter in numbers
Average diameter: 142,984 km
Mass (Earth = 1): 318
Average density: 1,326 kg / m3
Gravity at the equator (Earth = 1): 2.36 or 23.1 m / s2
Average distance from the Sun (Earth-Sun = 1 AU): 5.20 AU, or 778.6 million km
Inclination of the axis of rotation: 3.1 °
Rotation period (daytime cycle): 9:55 a.m.
Period of revolution around the Sun: 4,331 days
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