Jupiter

Jupiter is the largest planet in the Solar System: You could fit all the other planets inside it at the same time and still have room left!

It is a Gas Giant, (like Saturn, Neptune and Uranus). This means that is does not have a solid surface, but is a huge ball of gas. What we see is the top of the highest clouds.

The famous Red Spot (shown to the right) is a single giant storm, first seen over 300 years ago and still going strong! The picture shows how big it is compared to Earth.

Jupiter was the Roman King of the Gods.

As of May 2005, Jupiter is known to have 63 moons. The largest four (Io, Europa, Ganymede and Callisto) were discovered in 1610 by Galileo.

The first spacecraft to go to Jupiter was Pioneer 10 in 1973. Since then six other probes have been sent. The latest, called Galileo, is still there.

Facts and Figures
Orbit	778,330,000 km from the Sun or 5.20 AU
Radius	71,492 km
Mass	1.90 x 1027 kg or 318 Earths
Length of Year	11.9 Earth years
Length of Day	9.8 Earth hours
Surface Gravity	2.34 g
Surface Temperature	about -110 °C