moons

Jupiter is the Solar System’s largest planet, about 318 Earth masses, with a rotation period of roughly 9.9 hours per day. It is composed mainly of hydrogen and helium, with a metallic hydrogen layer that powers a strong magnetic field via a dynamo. The Great Red Spot is a storm at least 300–350 years old, about twice Earth’s diameter, whose roots extend roughly 300 miles (500 km) into the atmosphere. Jupiter’s magnetosphere extends 1–3 million kilometers toward the Sun and a tail over 600 million kilometers long, with a field 14–54 times stronger than Earth’s and new radiation zones near