Jupiter

Jupiter is the largest planet in the Solar System. It was the site of various battles, dating back to the Interplanetary War, and up to the Human-Covenant War.

History
Jupiter has been known since ancient times, however its four major moons, also known as Galilean moons, were only discovered in 1610 by Galileo. In 1892, a fifth moon of Jupiter was discovered, but smaller than the four others. Humans first sent spacecraft in late 1973, known as the Pioneer 10. Other spacecraft soon followed, thus discovering more moons and increasing the understanding of the gas giant. Jupiter has rings that are much fainter than those of Saturn's, which were discovered years later after the visit of the first spacecraft.

Humans began colonizing Jupiter's moons in 2080.

Jovian Moons Campaign
During the Jovian Moons Campaign of 2160, the Frieden secessionist movement attacked the UN Colonial Advisors stationed on Io. The attack led to the Jovian Moons Campaign and the beginning of the Interplanetary War.

Human-Covenant War
During the Human-Covenant War, Jupiter was once again a location of particular importance. Io Station detected a Covenant Fleet of 15 ships exiting Slipspace just outside of Jovian space a few moments before the Battle of Earth.

The Forerunner Dreadnought and Truth's Fleet escorting it passed Jupiter while on their way to Earth.

Characteristics
Average Orbital Speed: 13.07 km/s

Volume: 1.43128×1015 km³

Surface Area: 6.21796×1010 km²

Equatorial Rotation Velocity: 45,300 km/h

Surface Pressure: 20–200 kPa

Atmosphere:
 * 89.8% Hydrogen
 * 10.2% Helium
 * 0.3% Methane
 * 0.026% Ammonia
 * 0.003% Hydrogen deuteride
 * 0.0006% Ethane
 * 0.0004% Water