Jupiter

Jupiter is the largest planet in the Solar System. It weighs as much as 318 whole Earths (twice the mass of all the other planets combined!). Like most planets, Jupiter is a naked-eye object, known since antiquity. Galileo used a telescope to discover moons of planets. It is made of  gasses and ices with a little rock and is believed to have a solid core surrounded by liquid metallic hydrogen. This liquid metal gives the planet its magnetic field. Despite its distance from the Sun, Jupiter radiates more heat than it receives, a fact attributable to the huge mass of the planet and the movements of its gasses.

Jupiter’s most notable features are its giant red spot and its overall colors. The Great Red Spot is a huge spinning mass of gas which rotates slowly round the planet’s Southern Hemisphere. It is the size of 2 Earths. The belts and bands of color are caused by varying winds pushing gasses containing different allotropes of sulfur across the atmosphere.

Not long ago it was believed that Jupiter had no rings, but recently a thin system of rings has been discovered around the planet. Jupiter’s rings are believed to be made of small rocks and dust but, unlike other ring systems, they contain no ice.