Jupiter is the biggest planet in the solar system. It has a mean radius of 69.911 kilometers.
Jupiter also has over 50 moons that include Io, Europa, Ganymede and Callisto. These four large moons are called Galilean satellites because Galileo Galilei was the first person to observe them in 1610.
A distinct feature of Jupiter is its Great Red Spot, a large and swirling storm system. One year on Jupiter is as long as 12 Earth years.Learn more about Planets