Canon

Threshold

From Halopedia, the Halo wiki

Threshold
This is the bitmap image of Threshold from the multiplayer map Truth's skybox.
Astrographical

System:

Soell system[1][2]

Orbiting:

Soell[1][2]

Orbital position:

Seventh planet[1][2]

Moon(s):

Twelve, including Basis[1]

Physical

Diameter:

214,604 kilometers (133,348.7 mi)[1]

Atmosphere:

Gases

Hydrogen, helium, methane[1]

Liquids

Ammonia, water,[2] ammonium hydrosulfide, phosphorus compounds[3]

Societal

Demonym:

Thresholdian[1]

Government:

 

Threshold, also known as Soell VII,[5] is a gas giant, and the seventh and largest planet in the Soell system.[2] It was the gravity anchor for Installation 04, which was situated at the L1 Lagrange point between Threshold and its largest natural satellite, Basis.[6]

Threshold's Earth Survey Catalog number is B1008-AG.[6]

Overview[edit]

Artwork of Installation 04 in orbit of Threshold for Halo: Combat Evolved Anniversary's terminals.
The orbiting Installation 04 and asteroids.

Orbital characteristics[edit]

Threshold is orbited by twelve satellites. Threshold's largest natural satellite, is called Basis. The other satellites of Threshold are significantly smaller, but are nonetheless host to various Forerunner facilities.[2] Although none of Threshold's satellites have been extensively surveyed, all but two of them appear to contain Forerunner installations or are entirely artificial. The outposts functions are unknown, but they were likely used to provide maintenance for Installation 04.[1] Several small asteroids also orbit Threshold, near Installation 04.[7]

The most notable of Threshold's orbiting installations was Installation 04, situated at the L1 Lagrange point between Threshold and Basis.[1] Threshold's atmosphere is home to an extensive network of Forerunner gas mining platforms and refinery stations, hanging from a band-like low-orbital suspension grid in the upper atmosphere.[2][8] Although, by the mid-26th century, only a handful of these mines and refineries remain operational.[1] The Forerunner space station designated Deep-Space Anomaly 0198 by the UNSC is also in high orbit over the gas giant.[9]

Environmental features[edit]

Kez'katu-pattern Phantoms approaching the Threshold gas mine. Screenshot taken from the opening cinematic of The Arbiter.
A raging storm near a gas mine in Threshold's upper atmosphere.

Threshold is an immense gas giant with a diameter of 214,604 kilometres (133,349 mi), and twelve satellites, several of which are Forerunner installations. Threshold is the largest planet in the Soell system, and the seventh planet in Soell's orbit.[2] Threshold is purplish-orange in color,[10] and contains many rare and valuable gases.[4] Threshold's atmosphere is made up of white ammonia clouds, amber-colored ammonium hydrosulfide clouds, phosphorus compounds, ice crystals and other gases. The clouds are arranged in thin, tendril-like formations and resemble sinuous ribbons.[3] The planet's winds blow at hundreds of kilometers an hour. Threshold is known to have storms frequently rage in its atmosphere similar to the storms that occur on the planet Jupiter.[11][12][13] The planet has a core of liquid hydrogen.[14]

The pressure inside the gas giant is extremely powerful, and effectively able to crush any object that delves too deep into the planet's atmosphere. Threshold has a powerful magnetosphere that is easily capable of disrupting the magnetic fields of plasma weaponry such as plasma torpedoes. The temperature of the outer atmosphere of Threshold is around 300 degrees Celsius.[3] Further down, in the planet's denser atmosphere, temperatures reach over 1700 degrees Celsius.[15]

History[edit]

Prehistory[edit]

Over 100,000 years ago, Threshold was a part of the sizeable and extensive Forerunner ecumene. Wishing to harvest the gas giant's rare and valuable gases, the Forerunners used Threshold as a mining colony.[4] They built numerous automated gas mining complexes in the upper atmosphere of the planet, tethered to several band orbitals, used for harvesting the hydrogen, helium, and methane gas of the planet.[8]

Upon the discovery of the Flood, the Forerunners refitted some of the gas mines to serve as Flood research facilities. These facilities proved only one thing: more extreme measures were needed to combat the Flood and to keep them from spreading. At the end of their war against the Flood, the Forerunners chose Threshold as a staging point for one of the Halo superweapons: Installation 04. The Halo was placed on the L1 Lagrange point between Threshold and Basis and was designed to destroy all sentient life in the galaxy, thereby halting the spread of the Flood, due to starvation.[12]

Human-Covenant War[edit]

Threshold and Installation 04 are discovered by the C