A unique characteristic of Jupiter is that it's the largest planet in the solar system. It contains the Great Red Spot, a storm that has been observed for hundreds of years. Some scientists believe the storm is permanent.
Jupiter is about 318 times as massive as Earth. Even the Great Red Spot is about two or three times bigger than Earth. Astronomers believe that if Jupiter had been more massive, it would have ignited and become a star itself.
Jupiter has actually shrunk in size since it was first formed. Scientists believe that the planet is shrinking at the rate of about 0.8 inches per year. It was also much hotter when it was first formed than it is as of 2014.
Besides the Great Red Spot, Jupiter has bands of swirling cloud layers. The Great Red Spot also rotates counterclockwise and takes six days to circumnavigate the planet.
Jupiter has a system of faint rings. The planet's magnetosphere is about 14 times stronger than Earth's.
Jupiter has a vast number of moons. Scientists believe there are about 67. Fifty of them have been confirmed. The Jovian day lasts 10 Earth hours, though the Jovian year takes 12 Earth years. Jupiter was named after the chief Roman god.