JUPITER Fifth planet from the Sun Mean distance from Sun: 5.20 AU = 778,000,000 KM Diameter: 143,800 KM Mass: 317.89 Earths Density: 1.3 grams / cubic centimeter Surface temperature: -200 F Orbital period: 11 years, 321 days Jupiter is the Solar System's largest planet - its composition is more like a star than a planet. Bright belts, changing cloud structures, four main moons (each larger than Earth's satellite) and the Great Red Spot are all easily visible in small telescopes.