Editing Milky Way

{{Era|Forerunner|Covenant|Human|UNSC|HCW|Post}}

[[File:Milky_Way_2.jpg|thumb|The Milky Way as seen from [[Installation 00|the Ark]]. The pink 'dots' are massive patches of intense star formation.]]

[[File:Ssc2008-10a.jpg|thumb|An overhead view of the Milky Way.]]

The '''Milky Way''' is the [[wikipedia:galaxy|galaxy]] where the [[human]]s and the [[Covenant]] reside,<ref>'''[[Halo: Contact Harvest]]''', ''page 26''</ref> and is approximately 100,000 light years in diameter. It is a [[wikipedia:Barred spiral galaxy|barred spiral galaxy]] that lies within the [[wikipedia:Local group|local group]] of galaxies neighborhood, which is just a very small portion of the universe. Visible from [[Earth]] as a band of light in the night sky, the Milky Way is just one of many galaxies in the observable universe, although the sphere of influence of humanity and the other modern spacefaring civilizations is limited to only small portions of the Milky Way. The Milky Way is orbited by two small satellite galaxies known as the [[Magellanic Clouds]].<ref name="clouds">'''[[Halo: Cryptum]]''', ''page 268''</ref>

[[File:Milky Way.jpg|thumb|The Milky Way seen in infrared from Earth.]]

The Milky Way is a barred spiral galaxy of either [[wikipedia:SBb|SBb]] or [[wikipedia:SBc|SBc]] classification on the Hubble Sequence. It has two major arms, each sporting several minor arms that stem off of the major arm. One of these major arms, the [[wikipedia:Sagittarius Arm|Carina and Sagittarius Arm]], is home to the [[Orion Arm]]. Splotches of intense star birth and formation can be seen in the arms. These areas are pink/red in hue and appear as wisps or clouds situated in the galactic plane. These are easily seen on any level featuring the Milky Way in the sky ([[Isolation]], [[The Ark (level)|The Ark]], etc.).

===The Orion Arm===

{{Main|Orion Arm}}

The Orion Arm is the origin of [[human]]ity and their home planet Earth, with [[human colonies|at least 800 worlds]] inside human territory at the height of human colonial expansion. It is also the point of origin for several of the [[Covenant]] races along with a number of their colony worlds. The [[Forerunner]] homeworld [[Ghibalb]], as well as the [[Orion complex]] which housed the galaxy-spanning Forerunner [[ecumene]]'s core worlds, are also located in the Orion Arm.

The Orion Arm was the setting for the [[Human-Covenant War]] of the 26th Century and the ancient [[Forerunner-Flood war]], witnessing at least two massive wars. It is also the home of at least two [[Halo Array|Halo installations]] and a [[Portal at Voi|slipspace portal]] to [[Installation 00|the Ark]].

===Other Galactic components===

The Milky Way is composed of a disk, in which all the arms and the majority of galactic matter lies, and the galactic bulge, essentially the center of a galaxy. The bulge is home to the galactic nucleus, the dead center of a galaxy and home to an extremely dense clustering of ancient stars. The nucleus is also thought to support a supermassive black hole. Additionally, most known galaxies possess a halo of old and dying star clusters left over from the galaxy's formation. These clusters are situated up to 100,000 light years from the galactic bulge. Habitable planets may certainly lie within the halo, and some clusters may escape the range of the Halo Effect given their distance from the galactic center.

100,000 years before the present day, the previous galactic community was dominated by the [[Forerunner]]s, a now extinct species that possessed extremely advanced technology and [[Ecumene|an empire]] that spanned a significant portion of the galaxy. Millions of years before the rise of the Forerunners, an even more advanced civilization known as the [[Precursor]]s controlled the Milky Way. Having reached the pinnacle of [[Technological Achievement Tiers|technological advancement]], they were believed to have significantly contributed to the evolution of life across the galaxy, even created several species, such as Forerunners and humans. Over ten million years before the present, however, the Forerunners [[Forerunner-Precursor war|rose up against]] their creators in defiance of their decision to bestow their [[Mantle]] on humanity,<ref name="primordium">'''[[Halo: Primordium]]'''</ref> and seemingly ended their rule in the galaxy after destroying their last remnants in the [[Large Magellanic Cloud]].<ref>'''Halo: Silentium''', ''pages 181-182''</ref>

The Forerunners, originating from [[Ghibalb]] in the [[Orion complex]], ruled a large portion of the galaxy for millions of years, affecting the development of other species as they saw fit. Around [[150,000 BCE]], [[human]]ity, still composed of many species, arose from their homeworld Earth, known as "Erde-Tyrene" at the time. They mastered interstellar travel and began to move [[Prehistoric human civilization|their civilization]] along the Orion Arm of the Milky Way. They later [[Human-San 'Shyuum alliance|allied]] with the [[San 'Shyuum]] species, forming a prosperous interstellar empire based on the planet [[Charum Hakkor]]. Around [[107,445 BCE]], humanity and their San 'Shyuum allies came into contact with the Flood, a sentient parasite supposedly originating from the [[Large Magellanic Cloud]].<ref name="clouds"/> Hundreds of systems were lost to the parasite in the [[Human-Flood war|resulting conflict]]. Meanwhile, humanity's aggressive expansion and the perceived violations of the [[Mantle]] prompted the Forerunners to take action and begin [[human-Forerunner wars|a war]] against humanity. Although the Flood later withdrew and seemingly died out from the galaxy, it had already weakened the humans enough to allow the Forerunners to emerge victorious.<ref name="cryptum">'''[[Halo: Cryptum]]'''</ref>

Following the war in approximately [[106,445 BCE]], the Forerunners dismantled humanity's civilization, regressing them into a [[Technological Achievement Tiers|Tier 7 species]]. The remaining humans were devolved and exiled to their homeworld, where they slowly began to redevelop [[Erde-Tyrene civilization|a primitive civilization]] under the tutelage of the Forerunner [[Lifeshaper]], the [[Librarian]].<ref name="cryptum"/>

10,000 years after humanity's conflict with the Flood, the parasite resurfaced and attacked worlds of the Forerunners' domain. Encounters with the Flood led to the [[Forerunner-Flood war]], with the Flood consuming or killing the great majority of the galaxy's sentient species as the Forerunners first studied them, and then tried to stop them. Eventually, the Forerunners were forced to activate the ultimate weapon, the [[Halo Array]], in order to stop them - at the same time, killing its builders. The Forerunners built safe havens, including the [[Shield World]]s and [[Installation 00|the Ark]], to save the remaining sentient species in plan known as the [[Conservation Measure]], before [[Great Purification|activating the Array]], scouring the galaxy of all sentient life forms and killing the Flood except for samples kept on the Halos, then releasing the saved species from their havens to their home worlds.

The discovery of one of the Forerunners Halo installations set forth a series of events that would not only end the war, but also destroy the Covenant and begin a Covenant civil war, or [[Great Schism]]. Triggered by the replacement of the [[Sangheili]] with the [[Jiralhanae]] in the Covenant military hierarchy, the Sangheili left the Covenant, in the process that consumed a significant amount of the Covenant's populace and resources. A [[Swords of Sanghelios|major breakaway faction]] led by [[Arbiter]] [[Thel 'Vadam]], realizing that the [[Prophets]] were conducting an unjustified war against humanity and planning a misguided activation of the [[Halo Array]], allied with the UNSC to stop them, leading to the destruction of the Covenant in the [[Battle of Installation 00]].

Though the civilization of the Sangheili had plunged into chaos due to the [[Covenant remnants|breaking of the Covenant]],<ref name="glass">'''Halo: Glasslands'''</ref> the conflict between them and the Jiralhanae would still rage by [[2559]]. Humanity, as well, would continue to face conflict both within and without, in the form of resurgent [[Insurrectionist]] movements as well as various hostile [[Covenant remnants]]. [[Post-Covenant War conflicts|This irregular conflict]] was later characterized by significant Forerunner involvement, both in terms of contention for Forerunner artifacts but also the reawakening of the Forerunner commander known as the [[Ur-Didact]] and his [[Promethean]] armies on [[Requiem]].

[[File:Halo Star Map V2.png|300px|thumb|A near-accurate star map of several notable systems.]]

 

The development of the [[Shaw-Fujikawa Translight Engine]] in 2291 allowed humanity to leave the confines of its home star system for the first time and explore the wider galaxy, ushering in an age of rapid colonization and expansion. The first line of colony ships were unveiled in [[2310]], and over the next 28 years, the UNSC began terraforming and colonizing more than 210 worlds, which would become the Inner Colonies. Colonial expansion continued and by [[2490]], UNSC colonial space encompassed over 800 worlds, large and small, in the [[Orion Arm]]. The success of colonization of the [[Outer Colonies]] made the Inner Colonies the primary stronghold, both military and economic, though they relied heavily on raw materials supplied by the Outer Colonies. At the end of the Golden Age of human expansion in the twilight of the 25th century, tensions between the Inner and Outer colonies culminated in hundreds of civil wars waged across the Outer Colonies, collectively termed as the [[Insurrection]].

{{Main|Covenant}}

Because the Covenant have been spacefaring for over two millennia,<ref>'''[[Halo Encyclopedia]]''', ''page 30''</ref> and possess far superior [[astrogation|slipstream navigation]] technology to humanity, they have explored a significantly larger portion of the galaxy than humanity has. Based primarily in the [[Orion Arm]] of the Milky Way, it is unknown if they maintain territories outside of the region, but there are several homeworlds and colonies located in the Orion Arm. Additionally, the Covenant have discovered and explored several Forerunner [[shield world]]s as well as other Forerunner artifacts, from which they have acquired much of their advanced technology.

The [[Human-Covenant War]] has devastated numerous human worlds, but at least one [[Covenant]] world, [[Joyous Exultation]], was devastated by [[Danforth Whitcomb|Admiral Whitcomb]]'s [[NOVA bomb]] in retribution for the destruction of [[Reach]]. It is unknown if the separatists and loyalists destroyed worlds under the control of the other faction, but both [[Taming of the Hunters|Te]] and [[Unggoy Rebellion|Balaho]], the Lekgolo and Unggoy homeworlds respectively, were almost [[glassed]] during the [[Covenant]]'s history.

The Forerunners, having been spacefaring for millions of years and possessing slipspace technology allowing them to cross galactic distances in a negligible time, had explored significant portions of the galaxy. Their [[ecumene]] encompassed three million fertile worlds,<ref>'''Halo: Cryptum''', ''page 9''</ref> along with many artificial installations they had constructed. The Forerunners divided the galaxy into [[margin arc]]s and [[thema]]s, with the latter being defined by galactic-scale magnetic fields.<ref>'''Halo: Silentium''', ''pages 234-235''</ref> They were also capable of traveling [[intergalactic space|outside the galaxy]], including an expedition to the [[Path Kethona|Large Magellanic Cloud]] and the construction of the [[Ark]]s hundreds of thousands of lightyears from the galaxy.<ref>'''Halo 3''', campaign level ''[[The Ark]]''</ref>

 

 

*[[wikipedia:Perseus Arm|'''Perseus Arm''']]

*[[wikipedia:Cygnus Arm|'''Norma and Cygnus Arm''']]

*[[wikipedia:Scutum-Crux Arm|'''Scutum-Crux Arm''']]

*[[wikipedia:Sagittarius Arm|'''Carina and Sagittarius Arm''']]

===Orion Arm===

{{Main|Orion Arm}}

The Milky Way, and the [[Orion Arm]] in particular, has a large number of inhabited or, at least, habitable, planets within it, with the [[Unified Earth Government]] and the [[Covenant]] both maintaining distinct territories of their own. Other planets and systems were once home to the ancient [[Forerunner]]s, whose interstellar empire spanned the galaxy until their disappearance, as well as the contemporary empires of other species, including [[prehistoric human civilization|humanity]] and the [[San'Shyuum]].

 

*[[Human colonies#List of known colonies|Human systems and worlds]] {{C|[[Prehistoric human civilization#Sphere of influence|prehistoric humans]]}}

*[[Covenant#Known Covenant worlds|Covenant systems and worlds]]

*[[Ecumene#Known regions, systems and worlds|Forerunner systems and worlds]]

{{Clear}}

*The only engagement or conflict to take place "outside" the Milky Way in the modern times is the [[Battle of Installation 00]]. Two other cases of extragalactic conflict are known to have occurred in the distant past; the [[Battle of the greater Ark]] in the final days of the [[Forerunner-Flood war]] and the later stages of the [[Forerunner-Precursor war]] over ten million years earlier.

*''[[Halo: The Fall of Reach]]'' {{1st}}

*''[[Halo: Evolutions - Essential Tales of the Halo Universe]]''

**''[[Pariah]]''

**''[[Stomping on the Heels of a Fuss]]''

**''[[Midnight in the Heart of Midlothian]]''

*''[[Halo Legends]]''

**''[[The Babysitter]]''

**''[[Odd One Out]]'' {{C|Non-canon appearance}}

*''[[Birth of a Spartan]]''

*''[[Remember Reach Webfilm|Remember Reach]]''

**''[[Spaceport (Remember Reach)|Spaceport]]''

*''[[Scanned]]''

**''[[Terminal/Halo 4|Terminals]]''

*''[[Halo: Rebirth]]''

*''[[Halo: The Master Chief Collection]]''

**''[[Halo 2 Anniversary]]''

<references/>

[[Category:Astronomy]]