Meet the Guide Editor
Message from the Editor:
Kayar thinks of Jupiter as the Big Brother of the solar system, taking all the hits from incoming comets to defend the little inner planets like Earth. While not strictly true, the awe, admiration and fascination remains.
Jupiter Contributors

The Planet Jupiter in Our Solar System

Jupiter (Cassini image from NASA)Jupiter, the fifth of eight planets and the first of four gas giants, is the second largest astronomical object in our solar system after the Sun. Its most famous feature is its Great Red Spot - a massive storm that has been raging for centuries (at least). The rest of Jupiter has brightly-colored bands of gases moving rapidly in opposite directions with turbulence in between. One day on Jupiter is about 10 Earth hours, and one year on Jupiter is about 12 Earth years.

Jupiter has at least 63 moons. Eight of them, including the four largest - Ganymede, Callisto, Europa, and Io - orbit nicely about the equator, more or less. These probably formed when Jupiter did. The rest of them orbit every which way in a cloud around the planet, after Jupiter captured them in passing. Jupiter also has rings of dust from things crashing into the two innermost moons.

In the articles below, learn all about Jupiter, its moons and rings, the history of our explorations from Earth, solar system events like the Shoemaker-Levy impact, and other fun facts.

Latest Articles on Jupiter
Saturn's Moon Enceladus Grabs the Attention of Alien Life Hunters

The possible presence of water under the surface of Enceladus, one of Saturn's moons, has brought the satellite to the attention of exobiologists, a group of scientists dedicated...

Trojan Asteroids: Jupiter's Own Asteroid Belt

Some asteroids orbit the Sun along with Jupiter. These asteroids are called Trojan's and have found homes at a special place in Jupiter's orbit where the forces of gravity and...

Juno--The New Jupiter Probe

On August 5, Juno began a five year flight to Jupiter. On arrival, it will spend a year making measurements of the gas giant’s magnetic, gravity and radiation fields. It will...

Let's Find Out: What is the Weather Like on Jupiter

What do you know about Jupiter's weather? Did you know that the Great Red Spot on Jupiter is a storm? There is a lot more going on in Jupiter's atmosphere - read on...

Most Popular Articles on Jupiter
More About Jupiter
Impact! Shoemaker Levy 9 Comet and Jupiter

While we haven't had a good impact here on Earth in a good long while, they're fairly commonplace on the larger planets—especially the largest of them all, Jupiter. This...

Jupiter's Period of Rotation

Among the many amazing features of the planet Jupiter is its rate of rotation and the effects it produces. One of those effects is the hurricane-like storm we call the Great Red Spot...