Jumpin' Jupiter
There are no rockets powerful enough to hurl a spacecraft into the outer solar system and beyond. In 1962, scientists calculated how to use Jupiter's intense gravity to hurl spacecraft into the farthest regions of the solar system. We've been traveling farther and faster ever since.

Storm of the Centuries
Jupiter's Great Red Spot is a hurricane-like storm so large that almost three Earths could fit across it.

Mighty Moon
With a diameter of 5,262 km (3,270 miles) Jupiter's Ganymede is the largest moon in our solar system - bigger even than the planets Mercury and Pluto. If Ganymede orbited the Sun instead of Jupiter, it could easily be called a planet.

Hail to the King
Jupiter is by far the largest of the planets. If it were hollow, more than 1,300 Earths could fit inside. The giant planet contains two-thirds of all the planetary mass in the solar system and holds more than 60 moons in its gravitational grip.

Planet-Sized Pizza?
Jupiter's moon Io is the most volcanically active body in our solar system. Active volcanoes constantly spew material onto Io's surface. The moon's bizarre, blotted yellowish surface looks more like a pepperoni pizza than like the cratered surfaces of the other moons in our solar system.

The Hot Zone
Jupiter is not a people-friendly place. Radiation levels encountered by spacecraft visiting Jupiter are more than 1,000 times the lethal level for a human. Even heavily-shielded spacecraft like Galileo were damaged by the radiation.