La planète Jupiter est la cinquième du centre de notre système solaire. C’est la plus grosse et c’est une planète gazeuse.

Profil de Jupiter

• Jupiter est le quatrième objet le plus lumineux de notre système solaire.
  Seul le Soleil, la Lune et Venus brillent plus de notre planète. C’est l’une des cinq planètes visible à l’oeil nu de notre planète Terre.
• Jupiter est la cinquième planète du système et de loin la plus grosse.
• Elle est une géante gazeuse (comme Saturne, Uranus et Neptune).
  Ces planètes sont dites gazeuses en raison de l’épaisse atmosphère qui entoure leur noyau de dimension relativement faible.
• Les Babyloniens furent les premiers à enregistrer l’observation de Jupiter.
  C’était autour du 7^e ou 8^e siècle avant JC. Jupiter fut nommée pouf le roi des dieux Romains. Pour les Grecks, elle représentait Zeus, le dieu du tonerre. Les Mesopotamiens ont vu Jupiter comme « as the god Marduk and patron of the city of Babylon ». Germanic tribes saw this planet as Donar, or Thor.
• Jupiter a la journée la plus courte de toutes les planètes.
  Elle tourne sur son axe toutes les 9 heures et 55 minutes. La rotation rapide écrase légèrement la forme de la planète.
• L’oeil rouge est une tempête sur Jupiter.
  La tempête dure depuis plus de 350 ans au moins. Elle est tellement large que la terre peut facilement entrer à l’intérieur.
• L’intérieur de Jupiter est fait de rock, métal et « compound » d’hydrogène.
  Below Jupiter’s massive atmosphere (which is made primarily of hydrogen), there are layers of compressed hydrogen gas, liquid metallic hydrogen, and a core of ice, rock, and metals.
• Neuf engins humains ont visités Jupiter.
  Pioneer 10 and 11, Voyager 1 et 2, Galileo, Cassini, Ulysses, et les missions New Horizons. — The Juno mission is its way to Jupiter and will arrive in July 2016. Other future missions may focus on the Jovian moons Europa, Ganymede, and Callisto, and their subsurface oceans.

Jupiter’s Great Red Spot

Situated 22° south of Jupiter’s equator, the Great Red Spot is a storm that has been raging for at least 186 years. In fact, upper estimates suggest that this red and turbulent storm could have been in existence for over three and a half centuries. A giant red spot was seen on Jupiter in the seventeenth century, when telescopes first started to be used. However, it is unknown whether this is the same red spot that we see today, or whether Jupiter has had many such storms that have come and gone as the centuries pass.

The red spot circulates anticlockwise and takes six (earth) days to rotate completely. Another mystery surrounding the red spot is what makes it red: scientists have come up with several theories (for instance, the presence of red organic compounds) but as yet nobody knows for certain. That will be a question for future astronomy!

Jupiter’s Atmosphere

Jupiter’s atmosphere is special because it is the solar system’s largest planetary atmosphere. It is made up of hydrogen and helium, in roughly the same proportions as are found in the sun. However, it also contains much smaller amounts of other space gases, such as ammonia, methane and water. 90% of the atmosphere of Jupiter – a huge proportion – is made of hydrogen. It would be impossible for humans to breathe in this atmosphere. So, if you are thinking of travelling to space to do some hands on astronomy research, you would have to wear a breathing suit when visiting this planet.