Intro:
       Jupiter is the largest of all the planets in the solar system, 318 times more massive than earth. It was named after the king of the Roman gods. Jupiter revolves around the sun with a radius that is five times that of the earth. Each year it appears to shift about 30 degrees eastward which helps create a 12 year cycle. Jupiter is actually composed of mostly hydrogen and helium, unlike Earth's rocky composition. The central temperature of Jupiter is about 20,000 degrees Kelvin, compared to 7000 degrees for earth and 15,000,000 degrees for the sun. The coloration of Jupiter is a result of the interaction of sunlight to the atmosphere and the clouds. Different chemicals absorb different colors of light.

Energy:
       There are many theories for the energy source of Jupiter. Jupiter loses a large amount of heat in relation to its supply, which means that the planet must have some sourse that compensates for this. One possibility is primordial heat, which may not have been lost for the past 4.6 billion years. Another possible source is the conversion of gravitational potential energy to heat.

Rings:
       Like Saturn, Jupiter also has rings. While its rings are not as visible as Saturn's, Jupiter's rings are still very complicated. The largest density particles are along the outer edge and decreases inwards. The rings appear about twenty times brighter in scattered light than in reflected. The inner boundary of the ring is diffuse which means that material is spiraling into the planet's atmosphere. One can not distinguish the composition of the ring. It may have been formed from a residue of debris or it could be composed of a cometary material. Future analysis of the ring system is needed to determine the interactions and compositions.

A Brief Intro to the Moons:
       Jupiter has 16 moons, most of which are small and minor. It does, however, have four larger moons. The four Galilean satellites were discovered by Galileo in 1610. Callisto is the furthest with a heavily cratered surface. Ganymede, second most distant of the four and the largest satellite in the solar system, has heavily cratered regions surrounded by a grooved terrain. Europa is a white, highly reflecting body whose smooth surface is entirely covered with dark streaks up to 70 km in width and from several hundred to several thousand kilometers in length. Io, the closest to Jupiter of the four, has eight active volcanoes that are energized by the tidal effects of Jupiter's enormous mass. The red color of Amalthea, another satellite is due to a coat of sulfur particles. Four space probes have encountered the Jovian system. For more information on Jupiter's moon, please go to here.

Jupiter's Red Spot:
       The Great Red Spot is a large, oval mark. Many astronomers believe that the spot is an intense atmospheric disturbance similar to a hurricane. The Red Spot spans 23,000 km eastward and 12,400 km in the north south direction. This spot is bounded on the south by an eastward wind and a strong westward wind on the north. The Red Spot may have been formed when a large convective cell or a warm bubble was carried up from below.
       The spot drifts constantly for an interval of time and then accelerates or decelerates and settles to move at another constant rate. The Red Spot exists in a dessicated atmosphere where the water has condensed out. It is not free to drift along but is trapped in the described wind field.
       The color of the spot is different than the equatorial region which is also a reddish area. The Great Red Spot absorbs more of the blue, violet, and UV light.

Text Version

Learn more about:

This picture was taken by the Voyager 2 when it was only 24 million Km from Jupiter. The picture shows Jupiter and its largest moon Io.

The Red spot is Jupiter's most distinctive feature. Here it is taken by the