Sol System

The **Sol System**, also known as the **Terran System** or the **Solar System**, is the home star system of Humanity and the principal seat of the Galactic Terran Imperium in the galaxy. The system is named after its sun, Sol, and is part of the Sector Solar/Sol Star Sector. Its primary planets include Terra, the Capital world of the Imperium, and Mars, the first other Planet the Imperium colonized. It is located deeply within Imperial Core Territory of the Sol Star Sector and features the most defended, strategically important and economically valuable assets for the perseverance of the Imperium.

There are a total of eight major planets and many dwarf planets in the Sol System, some of which are also orbited by heavily-settled moons, such as Luna and Titan.

   The Sol System is home to the governing bodies of the Terran Imperium, including the Administratum, the Fabricator-General, and the Emperor Himself.

The Sol System, and the entirety of the Sector Solar, is guarded by Battlegroup Solar, the largest and most potent Battlegroup of the Imperial Navy.

Every world and moon in the Sol System -- barring a few mysterious exceptions -- is ringed with habitats and docking platforms, while all those whose surfaces are sufficiently solid play host to sprawling hab complexes, manufactoria and city-sized fortifications. An unending river of Humanity pours along the system's space lanes and fills its structures to capacity and beyond. It is amongst these masses that rebellion, sedition and heresy can and do foment.

From all across the Imperium come endless streams of pilgrims, merchants, bureaucrats, adepts, zealots, emissaries, refugees and countless others. Thousands of voidships translate from the Warp every day, entering strictly coordinated approach corridors that lead them to Venus, Mars, Jupiter, Luna and Terra itself.

**Defenses of the Sol System**

The Solar System is the most heavily defended system in the Terran Imperium, and perhaps the entire galaxy. A single layer of the defense may be equal to another Major Interstellar Civilization's Capital's defenses. Its permanently assigned defense fleet can rival entire navies, and reinforcements stand ready to support from the Sol Sector and from the entirety of the Imperium, for any attack on Sol and Terra has the highest priority.

Vast **Interdiction Fields** encompass the entire system, with the **Sol Flight Control** based on Terra controlling the Fields to open and close them for temporary Normalisation to allow for FTL jumps into or out of the system. The range of the Interdiction sphere encompasses virtually the entirety of objects caught by Sol's gravitational pull, with the Oort field building the edge. Within and near this edge millions of **Watchtower satellites** watch common approach routes, deep space frequencies and energy anomalies, other systems and more with telescopes, sensor-scanners and many more tools.

The **Terran Legion** is an entire army of Legionaries directly assigned to the protection of Terra and the Sol System. It is one of the most proudest, ancient and venerable Legions and to serve within one is considered a great honor. Approximately 1 Billion Terran Legionaries are deployed on the System's major planets, moons, space stations, orbital rings and other megastructures and on its immense warship fleet. The Terrain Legionaries maintain a permanent presence, and perform their own patrols and monitoring sweeps throughout the Sol System. It is they who supervise the vetting of the countless Imperial citizens who pass through Terra's monolithic spaceports every solar day. It is they who enact surprise sweeps and inspections of the Sol System's defences, following no set pattern or schedule beyond their own intuition to prevent any from predicting and avoiding their vigilance. They seed listening devices, spy-servitors and dictalarcenous subroutines through the hives of the Capital and beyond. They gather and analyse every scrap of information they can from even the darkest reaches of the Sol System, feeding ship names, population movements, labourers' shift schedules, demagogues' sermons, vox intercepts and more into macro-cogitators the size of battleships.

The Solar PDF numbers 100 Billion, spread on all major planets, space stations, moons etc. They are not generally deployed on warships of the IAN, which only carry Legionaries and Raiders as a Marine Infantry Force. They are deployed on garrisons, military facilities and in public, civilian and industrial environements, guarding the

Mars, Terra and several other vital planetoids have **planetary shields** designed to withstand the impact of heavy relativistic missiles as well as asteroids and the usual myriad of conventional weapon system employed on warships.

**Gigantic Mass Drivers** on Battle Stations or as their own independent weapons station are spread throughout the system to react to enemy fleets approaching or projectiles threatening it. Once targetting has been engaged its huge reactors power the enormous weapons to sling building sized missiles with Ultra-High-Yield or non-explosive warheads at their enemies with relativistic speeds.

A rather inconspicuous defense mechanism is that of **public population control**. Uncounted billions of microphones, cameras, surveillance drones and more surveill all but the most restricted areas in the Sol System and feed unimaginable amounts of data into a gigantic computer brain which analyzes ever sliver of information into a gigantic network feed. This is then fed to the Sol Central Computing Hub for further processing.

The system's halo-belt plays host to massive star forts, garrisoned by dedicated regiments of Astra Militarum and empyrically tethered in place. The rest of the outer system is densely laced with thousand-mile-wide fields of void mines, prowling system monitors and huge, vacuum-hardened hunter-Servitors of terrifying aspect.

Were the invader to overcome these hazards, they would find resistance stiffening the deeper they pushed into the system. Heavy naval patrols from the Battlefleet Solar thunder through the darkness, their craggy silhouettes presaging death to any who fall beneath their sights. Monitor-shrines, dock-fortresses, fighter bases and countless weapons platforms dot the darkness, their lumen winking like artificial constellations.

The Grey Knights, the Inquisition and the Adeptus Mechanicus all have holdings within the Sol System, boasting suitably ferocious defences. Moreover, since Guilliman's Throneworld Decree, Terra and her sister worlds can raise greater forces in their own defence than ever before.

When coupled with the efforts of the Solar Watch, a group within the Adeptus Custodes who have sworn binding oaths to keep guard over the Sol System, and the presence of the Imperial Fists' mighty mobile battle station *Phalanx* hanging in geostationary orbit above Terra, it is clear that the defences of the Sol System are all but impenetrable to invading armies. Yet there are subtler threats to the Golden Throne, and it is against these that the Adeptus Custodes must be especially vigilant.

Orbital/Fortresses, Quick Reaction Strike Groups, Myriad of EWIS for Anti-Stealth and early warning

**Sol**

Sol itself is surrounded by many 1.000x10.000km McKendree Cylinders built from

**Terra**

Terra, or, in the most ancient records, "**Earth**," is the Capital of the Terran Imperium and the original homeworld of Mankind and of the Emperor. It is the most sacred and revered place in all the worlds that comprise the Imperium. It has **4 Quadrillion Inhabitants**.

Billions of Human pilgrims from across the galaxy flock to Terra -- even the barren and contaminated soil that these pious folk now tread upon when they reach Humanity's homeworld is considered sacred by the faithful of the Imperial Creed.

Terra had been devastated during a Siege in the Great Strife, causing Terra to fall barren and contaminated, wiping out its entire biosphere. However, in the millenia since great efforts have been undertaken to terraform the homeworld of humanity from a Death World to a fertile and thriving paradise world.

Orous is heavily overpopulated on account of its status as the planet of origin of the human race. As a result of this, the planet's population has spread outward, building cities that soar into space and creating artificial structures that orbit the planet. These structures are independent eco-systems containing farms for agricultural production, industrial zones and residential areas.

The economic, cultural, governmental, religious and military center of the Imperium, ark and homeworld of mankind and acclaimed capital of the entire Milky Way galaxy. Myriads of shipyards, space stations and satellites orbit it, skyscrapers may as well be called "spacescrapers" for they go from the surface into the void, space elevators ease the transfer of cargo and passengers from orbit to the surface, Billions pilger there every day, and Millions of starships surround it at all times, controlled and overseen by the Infamous Sol Flight Control

Terra's surface is covered by gigantic Hive Cities which are both immense population centers and industrial factories with enormous amounts of output

The Hive cities of man, the industrial & polluted mega cities that feed the imperium

oldest known bastions of civilization in the universe

interstellar hub for bureaucracy and administration

   **Luna**

Humans first landed on Luna in the year 969.M2, making it the first world ever explored by Mankind in the ancient past. In the subsequent centuries, it was one of the first worlds colonised by humanity, who erected great domed cities above and below its airless surface.

Luna, Terra's only natural satellite, is a densely settled Civilised World of the Imperium. Its massive population lives in great cities built deep below the lunar regolith.

Luna is most famous for the gene-laboratories where the Emperor made the genetic breakthroughs that would ultimately culminate in the creation of the large numbers of Legionaries who comprised the Legions which brought Humanity victory and an end to the Great Strife.

Luna also boasts a large collection of orbital dockyards for starship construction and maintenance, for which it is often visited by the Warships of Battlegroup Solar.

    **Mars**

* **Mars**, also known as the "Red Planet," is the first and greatest Forge World -- the "Forge World Principal" -- of the Imperium. It is located in the Sol System and produces vast numbers of weapons, vehicles and other advanced technology for the Imperium and its war efforts throughout the galaxy.
	+ **Phobos (Orbital Fortress)** - Phobos is Mars' only remaining natural satellite. A small moon only 11 kilometres in diameter, Phobos' surface is completely covered in weapons-studded fortifications and is used as an orbital fortress that protects the Red Planet and its equatorial Ring of Iron.
	+ **Deimos - INFORMATION NEEDED** - constant supply of ammunition and ordnance, known as the Steel Forge, mass mined and converted until it was more star fort than celestial body, second moon of Mars, serves as a small Forge World with smog-ridden manufactoria that produce weapons and armour.

* **Titan** is the largest moon of the gas giant Saturn in the Sol System and is wholly controlled by the **Order Chapter of the Emperor's Chosen** psychically-active Warriors. The entire moon is shut off from outside intrusion and the Order Commander reports only to the Emperor himself. This isolation is both to keep tight security, complete secrecy of the Orders doings and to protect others from accidents which can be devastatingly destructive in psychic matters. Nestled at the base of the shadow of Mount Anarch, the fortress-monastery of the Chosen, known as the Citadel of Titan, juts from the ice sheets and oceans of liquid methane like a jagged black spire. Built by the Emperor over ten thousand standard years ago, the Citadel of Titan has endured through countless ages of war and strife. Covered with dust and shadow, the dark edifice is festooned with gigantic cannons and massive Lance turrets, their heavy barrels aimed out into the night. It is a forbidding sight that welcomes no visitors and brooks no trespass. In fact, even the existence of the citadel is a closely guarded secret, and in the populous space lanes of the Sol System vessels give this moon of Saturn a wide berth, their captains well aware that it does not pay to stray too close to the ominous moon.
	+ **Apex Cronus Bastion** - This mighty space station, which is the size of a small moon, orbits Titan and is considered one of the most formidable star fortresses in the Imperium.
	+ ***Archivum Titanis*** - This is where the battlefield reports of the actions conducted by the Chosen all across the galaxy are stored within the shelves of the Archivum.

* **Mercury (Mining World)** - Mercury is a small, Dead World and Mining World that orbits very close to Sol. Despite its unforgiving conditions, shoal facilities operate in Mercury's orbit.
* **Venus Industrial World** - Venus is an inner planet of the Sol System, and the second closest to Sol.

* **Ceres** - Ceres is a small dwarf planet located within the Sol System's inner asteroid belt. Ceres is home to Vox relay and communication stations that helped with communications between the inner and outer reaches of the system. Ceres was also home to various orbital habitat stations who were engaged in the industrial mining of the Asteroid Belt.

* **Jupiter (Gas Giant Mining World)** - Jupiter is a massive gas giant and the fifth planet of the Sol System. The orbital space docks and workshops that orbit Jupiter are home to massive Imperial Navy shipyards controlled by the Tech-priests of Mars. Moons of Jupiter are known to possess habitats used by the workers of the shipyards in Jupiter's orbit, all of which are powered by the constant stream of radiation emitted from Jupiter.
	+ **Ananke** - A small moon of Jupiterwith habitats on its surface
	+ **Iocaste** - A moon of Jupiter with habitats on its surface
	+ **Europa** - Located within the range of Jupiter's Galilean moons, Europa has been geo-engineered and terraformed into an ocean-moon
	+ **Io** - The seething orange mass of the moon of Io is home to a uninhabitable volcanic wasteland.
	+ **Ganymede (Aquila Adamant)** - One of the four greater Galilean moons of Jupiter that was known to have had ancient habitats on its surface and served as the central hub of the massive complex that made up the orbital Jovian Shipyards. massive hub-fortress of the Officio Logisticarum called Aquila Adamant. Its purpose is to supply, support, and archive the actions of the fleets and battle groups as they advanced across the galaxy.
	+ **Thule** - Thule is a small, irregular asteroid moon of Jupiter that served as the clandestine shipyard
	+ **Callisto** - Callisto was a Galilean moon of Jupiter known to hold residential orbitals above its surface
	+ **Kadal** - Kadal was the name of a satellite munitions fortress

**Saturn (Gas Giant)** - Saturn is a massive, ringed gas giant and the sixth planet of the Sol System. The moons of Saturn serve as the location for a massive complex of military bases and orbital shipyards. Any unidentified vessels nearing Saturn are promptly destroyed by its sophisticated orbital defences.

* **Titan (Fortress World)** - Titan is the largest moon of the gas giant Saturn and the largest moon in the Sol System. The fortress of Titan is carved entirely of basalt.

* **Mimas (Prison World & Penal Colony)** - Mimas is the closest major moon to Saturn, marred by an immense impact scar that covers a quarter of the surface. This crater houses the Imperial Prison Complex which contains the worst criminals hunted by the Imperial Law Enforcement Agencies and Intelligence Service, including most powerful psykers, who are kept in isolated cells with psychic wards woven into the walls and guarded by spezialised soldiers immune to psychic influences and powers.
* **Encaladus** - Encaladus houses a citadel and is a vast palace.
* **Tethys** - Tethys is the site of the hidden archive, access to which is restricted. secret research facility. Tethys is home to a number of daemons and other special xeno species trapped beneath its surface.
* **Iapetus (Imperial Navy Fortress)** - Iapetus is the furthermost major moon in orbit of Saturn, and home to a vast naval fortress and series of dockyards that serves various strike fleets. Iapetus was a stronghold of the Ringers, the culture that occupied parts of the Saturnian system before the coming of the Emperor and the Imperium during the Great Crusade.

* **Uranus (Gas Giant)** - Uranus is a massive gas giant and the seventh world of the Sol System. Though never habitable, it is home to orbiting human colonies. The moons of Uranus are used mostly for mining by the Imperium.
	+ **Ariel** - One of Uranus' major moons, Ariel is home to Imperial mining operations.
* **Neptune (Gas Giant)** - Neptune is a massive gas giant, the eighth and furthest major planet from Sol. Neptune was first colonized by humanity during the era known as the Age of Terra. By the time the Emperor reconquered Neptune for the Imperium during the Unification Wars, its inhabitants had been transformed into mutants by the isolation from Terra and the harsh environment, which caused them to be destroyed by the forces of the Emperor.
* **Pluto** - Pluto is a small dwarf planet located in the outer rim of the Sol System. It is home to relay stations which are responsible for warning Terra of any imminent invasion.
	+ **Charon** - Charon is the largest natural satellite of Pluto.
	+ **Styx** - Styx is a natural satellite of Pluto.
	+ **Nix** - Nix is a natural satellite of Pluto.
	+ **Kerberos** - Kerberos is a natural satellite of Pluto and is used as a heavily armed orbital fortress.
	+ **Hydra** - Hydra is a natural satellite of Pluto and houses an Astropathic-relay station.

## Notable Celestial Objects

* **Asteroid Belt** - The Asteroid Belt lies between Mars and Jupiter and separates the Inner and Outer Solar System. Ceres is the largest settlement of the Asteroid Belt. The Asteroid Belt is populated by various mining operations and orbital habitat stations, and was formerly controlled by Belter Coalitions before the Unification Wars.
* **Kuiper Belt** - Another asteroid belt, the Kuiper Belt is nearly 20 times wider and 200 times larger than the inner Asteroid Belt. The Kuiper Belt reaches from the orbit of Neptune and out towards the Sol System's Oort Cloud. Several celestial bodies reside within the Kuiper Belt, including Pluto and its moons, and the dwarf planets Haumea and Makemake.
* **Centaurs** - The Centaurs are small, dwarf planets that usually feature unstable orbits due to previous encounters with larger planetary bodies. Centaurs mostly exist in the outer reaches of the Sol System, although due to their unstable orbits they sometimes cross into the Inner Solar System.
* **Comets** - Comets are small, icy bodies that usually have highly eccentric elliptical orbits, entering the Inner Solar System and then leaving for many hundreds or thousands of standard years.
* **Oort Cloud** - The Oort Cloud is a massive, spherical cloud of predominantly icy planetesimals that surrounds the entire Sol System.