Jupiter

## Jupiter • Sol V

**Jupiter** is the fifth and largest planet in the Sol system. The Jovian system is home to over 5 billion people who primarily live in orbit of the gas giant or on the four Galilean moons. Jupiter is the primary source of Helium-3 for the Sol system, and is home to the Jupiter Shipyards making it of high strategic value. Jupiter and it's moons are a protectorate of the United Nations of Earth.

## Physical Characteristics

Jupiter is a gas giant primarily composed of gas and liquid rather than solid matter. It is the largest planet in the Sol system with an equatorial diameter of 139,822 kilometers, making it over ten times larger than Earth.

### Atmosphere and Composition

The atmosphere of Jupiter extends to a depth of 3,000 kilometers below the cloud layers, after which it transitions into the liquid interior of the planet. The atmosphere is approximately 76% hydrogen and 24% helium, with trace amounts of methane, water vapor, ammonia, and silicon based compounds.

Saturn and Jupiter are known to be similar in composition.

#### The Great Red Spot

Prior to the 23rd century Jupiter was well known for the Great Red Spot, a massive anticyclonic storm that was the largest in the Sol system. It was the most recognizable feature on Jupiter owing to its red-orange color whose origin is unknown Located 22 degrees south from Jupiter's equator it produced wind speeds of up to 432 km/h. The Great Red Spot was believed to have been first observed in 1665 or 1713, and completely dissipated sometime in 2212, meaning that it lasted for at least 499 years.

### Planetary Rings

Jupiter has a faint planetary ring system composed of three main segments, the main ring, the halo ring, and the Gossamer rings. The main and halo rings consist of dust believed to be ejected from the moons Metis and Adrastea, which is drawn into orbit around Jupiter due to it's strong gravitational influence. In a similar manner, materials from Thebe and Amalthea are believed to be the source of the dusty Gossamer rings.

## Moons

Jupiter has 97 natural satellites of these 81 are less than ten kilometers in diameters. The four largest moons are Io, Europa, Ganymede, and Calisto, collectively known as the "Galilean moons", these were the first moons discovered to be orbiting another planet besides Earth.

## History

### Early exploration

The first spacecraft to visit Jupiter was *Navigator 5* in August of 1967. Navigator 5 obtained the first close-up images of Jupiter and its moons. *Navigator 10* would make another flyby of Jupiter in 1973 gathering information on the planet's atmosphere and radiation environment. The *Navigator 10* mission also improved understanding of the Galilean moons and brought the first hints of a subsurface ocean on Europa.

The first spacecraft to orbit Jupiter was the *Jupiter-Europa System Surveyor (JESS)* which reached the planet in October of 1992. *JESS* performed several close flybys of Jupiter and the Galilean moons, it tracked lightning in Jupiter's atmosphere, mapped the system's radiation belts, and confirmed the existence of subsurface oceans on Europa, Ganymede, and Callisto. *JESS* intentionally entered Jupiter's atmosphere on May 7th 2001 and was destroyed in order to prevent contamination of life on Europa.

The *Zeus* spacecraft would later be launched to locate and map potential resources within Jupiter's atmosphere. The most notable of which being Helium-3 which was seen as a crucial component of nuclear fusion power.

### Later exploration and manned missions

2013 saw the launch of the *Galilean Hopper* mission which sought to study the surfaces of the Galilean moons. The hopper took the first samples of Europa's subsurface ocean and in doing so discovered several single cellular lifeforms living within the ocean. This discovery brought a lot of attention to the Jovian system and several more missions were launched to study Jupiter and it's moons.

With the continued improvements in nuclear propulsion, a manned mission to Jupiter became more plausible. Launching in 2027, the Juno 1 mission became the first time humans had travelled into the outer solar system. However the crew would eventually succumb to radiation sickness brought on by the powerful radiation belts, the entire crew died before returning to Earth.

The tragedy of Juno 1 led humans to focusing on improvements in radiation shielding in space, and radiation medication in order to continue the exploration of Jupiter and the outer solar system.

### Colonization

Colonization of the Jovian system had been considered for many decades, however the time it took to travel from Earth to Jupiter made it difficult to justify. The invention of the Sakiko-Köhler fusion drive however reduced the travel time from two and a half years to just a few weeks. Juno Station began construction in 2160 and became the central hub for colonization of the outer solar system.