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Human scientists have studied Jupiter's winds to learn about the formation of storms. The gas giant's intense radiation, planetary ring system, and its orbital path have also been analyzed by scientists to help them explain other mysteries in the galaxy.
Jovian Moons Campaign
In 2160, the Frieden secessionist movement attacked the UN Colonial Advisors stationed on Io. The attack led to the Jovian Moons Campaign, which was one of the conflicts that culminated in the Interplanetary War.
During the Human-Covenant War, Jupiter was once again a location of particular importance. On October 20, 2552, the High Prophet of Regret's Fleet of Sacred Consecration exited slipstream space relatively close to Jupiter. Io Station detected the Covenant fleet of fifteen ships and reported the discovery to Fleet Admiral Lord Terrence Hood a few moments before the Battle for Earth.
Later, around November 15-16, 2552,[Note 2] the Forerunner Dreadnought and an escorting fleet of the High Prophet of Truth passed Jupiter while on their way to Earth at the time John-117 commandeered a Type-32 Ghost and crashed it into a large number of Covenant troops. Believing the Spartan to be dead, the Prophet of Truth orders the crew of the Forerunner Dreadnought to jump further in-system and enter Earth's atmosphere on November 17, 2552. Following the Covenant's invasion across the Sol system, many habitats of Jovian colonies survived the Covenant assault largely unscathed.
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