Editing Threshold gas mine

{{Status|Canon}}
{{Base infobox
|image=[[File:H2A - Threshold gas mine.jpg|300px]]
|location=[[Threshold]], [[Soell System]]<ref name="HW">[https://www.halowaypoint.com/en-us/universe/locations/threshold-gas-mine ''Halo Waypoint'': ''Threshold gas mine'']</ref>
|purpose=*[[Hydrogen]], [[helium]] and [[methane]] collection and refinement{{Ref/Reuse|HW}}
*[[Flood]] containment and research{{Ref/Reuse|HW}} {{C|later}}
|length=
|armament=
|complement= [[Aggressor Sentinel]]s{{Ref/Reuse|oracle}}
|built=Before c. [[97,445 BCE]]
|destroyed=[[2552#October|October 20, 2552]]
|usage=[[Forerunner-Flood war]]
|controlledby=
|notable=Base of operations for [[Sesa 'Refumee's heretic faction]]{{Ref/Reuse|ReferenceA}}}}
{{Quote|This mining facility predates [[Installation 04|Installation Alpha]] by several hundred years. It was retrofitted to research possible offensive and defensive measures against the [[Flood]]. Indeed, I designed and oversaw the construction of this facility's various outbreak management systems.|[[343 Guilty Spark]]}}

The '''Threshold gas mine''' was a large [[Forerunner]] structure suspended in the atmosphere of the gas giant [[Threshold]], the planet around which [[Installation 04]] orbited. It was an expansive automated facility that was created and used by the Forerunners and later, by [[Sesa 'Refumee's heretic faction]]. It was destroyed when it fell into Threshold and was crushed by the planet's gravity.{{Ref/Level|Id=oracle|H2|[[The Oracle]]}} It was one of many similar facilities on Threshold.<ref name="art">''[[The Art of Halo]]''</ref>

==Design==
[[File:GasMineSchematic.jpg|thumb|left|250px|A schematic of the gas mine.]]
The gas mine was originally intended to be used to mine [[hydrogen]], [[helium]], and [[methane]] from [[Threshold]]'s atmosphere.{{Ref/Reuse|HW}} Hanging from a larger installation higher in the atmosphere, the mine was shaped somewhat like a grappling hook, with one center shaft and many legs bending down, and inwards it has three tubes extracting gas from Threshold. The station was divided into five modules: two gas refinement arms, each with its own cargo hangar, two laboratory modules for the research of the [[Flood]], and the final module was the control section of the mine. Each of these modules could be accessed by catwalks or landing sites.

The main cable was held in place by three equidistant holds on the top level; supposedly the holds could be released by the main control of the station. The inside of the gas mine was a curious mix of Forerunner aesthetic and factory, with dozens of moving energy conveyor belts carrying gas canisters about. There was a large gas storage hold, which was accessed by a large circular [[lift]]. This hold contained hundreds of canisters, most of which contain Flood. A series of three cables connected the mine to the larger structure overhead; this was a fail-safe in case of a Flood infestation.{{Ref/Level|H2|[[The Oracle]]|Detail=343 Guilty Spark monologue}}

==History==
The gas mine was created by the Forerunners several centuries before the construction of [[Installation 04]],{{Ref/Reuse|oracle}} with the sole purpose of mining gas from the atmosphere of Threshold. It operated on a completely automated basis for "untold centuries" with a resident contingent of [[Sentinel]]s to maintain the facility.{{Ref/Reuse|art}}

However, after the Flood was discovered, the Forerunners retrofitted several areas of the gas mine into laboratories to study Flood specimens. [[343 Guilty Spark]], the future [[monitor]] of [[Installation 04]], personally oversaw some of these modifications. A few hundred years passed, however, with no successful defense against the Flood, eventually forcing the Forerunners to activate their weapon of last resort; the [[Halo Array]].

The gas mine was unaffected by the first activation of the rings and its contained Flood remained intact and untouched for over 100,000 years, until the year [[2552]].

===Raid on the gas mine===
{{Main|Raid on the Threshold gas mine}}
In 2552, the [[Fleet of Particular Justice]] stumbled upon the system when pursuing the {{UNSCShip|Pillar of Autumn}}. The [[Prophet of Stewardship]] sent an artifact retrieval team led by [[Sesa 'Refumee]] and [[Loka 'Bandolee]] to the gas mine attempting to retrieve any useful Forerunner technologies they could find;{{Ref/Reuse|HW}}{{Ref/Novel|TF|Detail=Adjunct: ''[[Priority Broadcast Log/Eleventh Cycle, Third Unit]]''}} however, at the conclusion of the [[Battle of Installation 04]], the group found itself marooned on the mine.

While there, the group encountered [[343 Guilty Spark]], having arrived at the gas mine from the remains of Installation 04.<ref>''Halo: Combat Evolved Anniversary'', ''[[Terminal (Halo: Combat Evolved Anniversary)|Terminal 11]]''</ref> Listening to his words and finding out the truth about the Halos and the [[Great Journey]], Sesa 'Refumee led [[Sesa 'Refumee's heretic faction|a rebellion]] and began broadcasting their beliefs across Covenant communications channels, attracting the attention of other Covenant personnel, including the [[High Prophets]]. Dubbing his movement "heresy", the High Prophets ordered [[Special Operations]] forces led by [[Rtas 'Vadum]]ee and [[Arbiter]] [[Thel 'Vadam]]ee to attack the gas mine and end 'Refumee's movement forever.

[[File:H2A-Gas mine raid.png|thumb|250px|Covenant forces deployed to the gas mine.]]
The surprise attack went well; the Covenant forces were able to infiltrate the facility and pursue 'Refumee, destroying many heretic [[Type-26 Banshee|Banshees]] along the way.{{Ref/Level|Id=ReferenceA|H2|[[The Arbiter]]}} But complications arose when the [[Flood]] were released from their restraints by the Heretics,{{Ref/Reuse|oracle}} and overran the entire facility. The Flood multiplied quickly, infecting and killing most of the heretic forces, making it difficult for the Covenant to secure the facility. 'Refumee locked himself in the inner section of the mine, safe from both the Flood and an approaching maelstrom, but the Arbiter responded bluntly by cutting the cables holding the mine up, sending it into freefall. This forced the heretic leader to escape his hideout with an attempt to evacuate aboard a {{Pattern|Kai|Seraph}} fighter, but the Arbiter caught up to him and they had a intense battle where he was killed. Shortly thereafter, [[Tartarus]] appeared in a Phantom, and he, the Arbiter, the special operations forces, and 343 Guilty Spark escaped the mine before it fell into Threshold's inner atmosphere, where it was subsequently destroyed along with the surviving Heretic forces within and the Flood.{{Ref/Reuse|oracle}}

== Trivia ==
*On ''[[The Oracle]]'', if the player jumps just before the station is detached, the entire station will freefall out from under the player, sending them toward a kill barrier.
*The gas mines are the setting of a cut ''[[Halo 2]]'' multiplayer level named ''[[Anchor Point]]''.

==Gallery==
===Concept art===
<gallery>
File:H2-Concept-ThresholdGasMine-Sketch.jpg|A sketch of the gas mine from the ''[[Art of Halo]]''
File:H2-ThresholdGasMine-Concept.jpg|Concept art of the gas mine above Threshold in the ''Art of Halo''.
File:H2A GasMineHangar Keyshot Concept.jpg|Concept art of the facility's hangar for ''[[Halo 2: Anniversary]]''.
File:H2A ThresholdGasMine Concept.png|Concept art for the structure above the mine.
File:H2A ArbyGasMine Concept.png|Concept art of Thel 'Vadam inside the gas mine in the [[Blur Studio]] cutscene.
File:H2A Concept GasMinePlatform.jpg|Concept art of an exterior platform on the gas mine.
File:H2A Concept CannedFlood.jpg|Concept art of the cans containing Flood [[pod infector]]s.
</gallery>

===Screenshots===
<gallery>
File:Gasmine.jpg|Three [[Kez'katu-pattern Phantom|Phantoms]] approaching the mine in order to eradicate [[Sesa 'Refumee's heretic faction]] in ''Halo 2''.
File:Gasgiant.jpg|The gas mine, high above a storm raging on the planet Threshold.
File:H2A TheArbiter Loadscreen.png|The gas mine in ''Halo 2: Anniversary''.
File:H2A TheOracle Loadscreen.png|A platform exposed to Threshold's atmosphere.
File:H2A-Gas mine cable.png|The triple-cable system at the top level of the gas mine.
File:H2A-Gas mine free-fall.png|The gas mine in free-fall.
File:Threshold Gas Mine Waypoint.jpg|The gas mine in Threshold's atmosphere.
File:Threshold Gas Mine Waypoint 2.jpg|A schematic of the gas mine.
</gallery>

==List of appearances==
*''[[Halo 2]]'' {{1st}}
*''[[Halo: Combat Evolved Anniversary]]''
**''[[Terminal (Halo: Combat Evolved Anniversary)|Terminals]]''
*''[[Halo 2: Anniversary]]''
**''[[Terminal (Halo 2: Anniversary)|Terminals]]''

==Sources==
{{Ref/Sources}}

{{Forerunner|array}}
[[Category:Space stations]]
[[Category:Forerunner installations]]
[[Category:Military bases]]