Learn about Jupiter, the largest planet in the solar system, in this video from NASA. Dramatic visualizations and satellite images show Jupiter's size compared with Earth, its fast rotation, and its dynamic cloud systems (including the famous Great Red Spot). In 1994, Jupiter's gravity pulled apart comet Shoemaker-Levy 9 and cometary fragments collided with the planet, illustrating the role that Jupiter may play in helping to protect Earth from dangerous impacts. The video also looks at Jupiter's numerous moons and explores the diverse characteristics of its four largest: Io, Europa, Ganymede, and Callisto.