|Jupiter, Gas Giant
Jupiter is the giant of our solar system. It is 1,400 times the size of Earth, and over half a billion kilometers away. We think of Jupiter as a failed star, made up of material a lot like that in the early solar system. That's why scientists believe that studying Jupiter could tell us what the solar system was like billions of years ago.
Jupiter alone is twice as massive (weighs twice as much) as all of the rest of the planets combined! It is surrounded by a thin ring made of dust, has 16 moons and has a dense fluid core which generates a powerful magnetic field. Jupiter's magnetic field is huge, stretching millions of miles into the solar system. Its atmosphere is full of lightning and gigantic hurricane-like storms. One of these storms, the Great Red Spot, is as wide across as the Earth and has been around for at least 100 years - maybe as long as 300 years. Galileo Galilei pointed a telescope at Jupiter in 1610, and discovered its four largest moons, Io, Europa, Ganymede, and Callisto.
Jupiter and the Shoemaker-Levy Comet
Comet Shoemaker-Levy 9 collided with Jupiter during the third week of July 1994. The impacts of the cometary fragments released more energy into Jupiter's atmosphere than all of Earth's nuclear arsenals. More on the comet...