This image of Jupiter was taken by Voyage I. Click on image for full size (16K JPG) Courtesy of NASA

Jupiter is the largest planet in our solar system. It is also one of the brighter objects in the night sky. No one knows for sure who discovered Jupiter, but we know the ancient Greeks named him after the god, Zeus.

The most famous feature of Jupiter is the Great Red Spot. This violent storm has been watched from Earth since the 1600's. But it wasn't until the 1930's that we knew what Jupiter was made of. Astronomer Rupert Wildt researched the planet and found the atmosphere is mostly hydrogen and helium.

Beginning in 1973, the United States sent four spacecraft to observe this giant planet. Pioneer 10 and 11, along with Voyager I and II, sailed past Jupiter. They gathered many images that we still see today.

Jupiter's moons are too! Galileo discovered four of the larger moons: Io, Europa, Ganymede and Callisto in 1610. Most of the other moons were found by the Voyager spacecraft during its flyby.