Jupiter: Facts & Figures

A true-color image of Jupiter taken by the Cassini spacecraft. The Galilean moon Europa casts a shadow on the planet's cloud tops.

Jupiter, the most massive planet in our solar system -- with dozens of moons and an enormous magnetic field -- forms a kind of miniature solar system. Jupiter does resemble a star in composition, but it did not grow big enough to ignite. The planet's swirling cloud stripes are punctuated by massive storms such as the Great Red Spot, which has raged for hundreds of years.

Discovered By Known by the Ancients Date of Discovery Unknown Orbit Size Around Sun (semi-major axis) Metric: 778,340,821 km English: 483,638,564 miles Scientific Notation: 7.7834082 x 108 km (5.2028870 A.U.) By Comparison: 5.203 x Earth Perihelion (closest) Metric: 740,679,835 km English: 460,237,112 miles Scientific Notation: 7.40680 x 108 km (4.951 A.U.) By Comparison: 5.035 x Earth Aphelion (farthest) Metric: 816,001,807 km English: 507,040,015 miles Scientific Notation: 8.16002 x 108 km (5.455 A.U.) By Comparison: 5.365 x Earth Sidereal Orbit Period (Length of Year) 11.862615 Earth years 4,332.82 Earth days By Comparison: 11.863 x Earth Orbit Circumference Metric: 4,887,595,931 km English: 3,037,011,311 miles Scientific Notation: 4.888 x 109 km By Comparison: 5.200 x Earth Average Orbit Velocity Metric: 47,002 km/h English: 29,205 mph Scientific Notation: 1.3056 x 104 m/s By Comparison: 0.438 x Earth Orbit Eccentricity 0.04838624 By Comparison: 2.895 x Earth Orbit Inclination 1.304 degrees Equatorial Inclination to Orbit 3.1 degrees Mean Radius Metric: 69,911 km English: 43,440.7 miles Scientific Notation: 6.9911 x 104 km By Comparison: 10.9733 x Earth Equatorial Circumference Metric: 439,263.8 km English: 272,945.9 miles Scientific Notation: 4.39264 x 105 km By Comparison: 10.9733 x Earth Volume Metric: 1,431,281,810,739,360 km3 English: 343,382,767,518,322 mi3 Scientific Notation: 1.43128 x 1015 km3 By Comparison: 1321.337 x Earth Mass Metric: 1,898,130,000,000,000,000,000,000,000 kg Scientific Notation: 1.8981 x 1027 kg By Comparison: 317.828 x Earth Density Metric: 1.326 g/cm3 By Comparison: 0.241 x Earth Surface Area Metric: 61,418,738,571 km2 English: 23,713,907,537 square miles Scientific Notation: 6.1419 x 1010 km2 By Comparison: 120.414 x Earth Surface Gravity Metric: 24.79 m/s2 English: 81.3 ft/s2 By Comparison: If you weigh 100 pounds on Earth, you would weigh 253 pounds on Jupiter. Escape Velocity Metric: 216,720 km/h English: 134,664 mph Scientific Notation: 6.020 x 104 m/s By Comparison: 5.380 x Earth Sidereal Rotation Period (Length of Day) 0.41354 Earth days 9.92496 hours By Comparison: 0.41467 x Earth Effective Temperature Metric: -148 °C English: -234 °F Scientific Notation: 125 K Atmospheric Constituents Hydrogen, Helium Scientific Notation: H2, He