Sol System
NOTICE: This page is a Work in Progress as much of the lore/Development for the game is yet to be established.
The Sol System is the native star system of Humanity and the location of their homeworld, Earth. Centered around the stable G2V class star known as Sol, it serves as the administrative heart of the United Nations and the primary operational headquarters of the United Nations Space Fleet (UNSF) as of 2261 AD. Located within the Orion Arm of the Milky Way galaxy at galactic coordinates (-26670, 0, 56), the Sol System represents not only the cradle of human civilization but also the crucial jumping-off point for humanity's recent expansion into the cosmos, enabled by the advent of practical faster-than-light (FTL) travel technology in the mid-23rd century.
| System Data (As of 2261 AD) | |
|---|---|
| File:SolSystemPlaceholder.png | |
| Central Star | Sol |
| Location (Galactic Coordinates) | -26670, 0, 56 (Orion Arm, Local Bubble) |
| Star Class | G2V |
| Age (Approx.) | ~4.6 Billion Years |
| Known Planets | 8 (Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune) |
| Known Dwarf Planets (Scattered Disk) | 5+ (including Ceres [Asteroid Belt], Pluto, Eris, Haumea, Makemake, Sedna) |
| Primary Inhabited World | Earth (Humans) |
| Other Populated Bodies | Luna (Earth's Moon), Mars (Limited Colonization/Outposts) |
| Governing Body (Local) | United Nations |
| Primary Spacefaring Org. | United Nations Space Fleet (UNSF) |
| Stellar Characteristics | |
| Habitable Zone (Est.) | ~0.63 AU – ~1.23 AU |
| Frost Line (~150K) | ~2.89 AU |
| Lava Line (~1200K) | ~0.049 AU (7.27 million km) |
| Dust Sublimation Line (~2000K) | ~0.018 AU (2.73 million km) |
| Roche Limit | ~1,077,467 km |
| Hill Radius (Sphere of Influence) | ~3.62 LY |
| Oort cloud Outer Limit (Est.) | ~1.81 LY |
Structure
The Sol System exhibits a structure common to many stable G-class stellar systems, characterized by a distinct zonation based on temperature and gravitational influence. It comprises an inner region of rocky planets, separated from the outer region of gas and ice giants by a dense asteroid belt. Beyond the giant planets lies a vast trans-Neptunian region containing dwarf planets and numerous icy bodies, culminating in the vast Oort Cloud which defines the system's gravitational boundary.
- Inner Sol System: Home to four terrestrial planets (Mercury, Venus, Earth, Mars), characterized by solid surfaces and metallic cores. This region lies entirely within Sol's Frost Line.
- Asteroid Belt: A circumstellar disc located roughly between Mars and Jupiter, populated by countless asteroids, minor planets, and the dwarf planet Ceres. It represents material from the protoplanetary disk that failed to coalesce into a full-sized planet due to Jupiter's gravitational influence.
- Outer Sol System: Dominated by four giant planets (Jupiter, Saturn, Uranus, Neptune), divided into two gas giants and two ice giants. These planets formed beyond the Frost Line, allowing them to accrete significant amounts of gas and volatile ices.
- Scattered Disk (Kuiper Belt Analogue): An expansive torus of icy bodies beginning near Neptune's orbit and extending outwards. It is considered the primary reservoir for short-period comets and houses several known dwarf planets.
- Oort cloud: An enormous, vast spherical cloud of icy planetesimals, confirmed through indirect observation and gravitational modeling, forming the outermost gravitational boundary of the system and extending perhaps as far as 1.8 light-years from Sol.
Central Star: Sol
Sol is a mature G2V yellow dwarf star, approximately 4.6 billion years old, providing the energy that sustains the system. Its stability has been a key factor in the development of life on Earth. Astrophysical parameters determined by UNSF sensor standards define key environmental boundaries: the Habitable Zone (~0.63-1.23 AU) denotes the region where surface liquid water is possible under suitable atmospheric conditions; the Frost Line (~2.89 AU) marks the distance beyond which water ice remains stable; the Lava Line (~0.049 AU) represents the distance within which silicate rock begins to melt; and the Dust Sublimation Line (~0.018 AU) is the innermost region where even refractory dust grains vaporize. Sol exhibits typical stellar activity, including solar flares and stellar wind, which are constant operational considerations for interplanetary and interstellar travel originating from the system. Its overall gravitational sphere of influence (Hill Radius) extends roughly 3.62 light-years into interstellar space.
Planetary System
The Sol System contains eight planets, numerous dwarf planets, moons, asteroids, and comets, all orbiting Sol.
Inner Planets
Mercury
The smallest planet and closest to Sol. A heavily cratered, rocky world with virtually no atmosphere, experiencing the most extreme temperature swings in the system. Its proximity to Sol makes operations challenging due to intense radiation and thermal stress.
Venus
Often called Earth's "sister planet" due to similar size and mass, but vastly different in environment. Venus possesses an extremely dense, toxic atmosphere dominated by carbon dioxide, resulting in a runaway greenhouse effect and crushing surface pressure. Extensive robotic exploration preceded the FTL era, confirming its inhospitable nature.
Earth
The third planet and jewel of the system, Earth is the homeworld of Humanity. Characterized by vast oceans of liquid water, a protective magnetic field, a dynamic atmosphere rich in nitrogen and oxygen, and abundant biodiversity. It remains the most densely populated body in the system and serves as the political, cultural, and economic center of human civilization, hosting the headquarters of the United Nations and the United Nations Space Fleet. Its large natural satellite, Luna (the Moon), hosts significant scientific outposts and infrastructure supporting Earth-orbit operations.
Mars
The fourth planet, known as the "Red Planet" due to iron oxide on its surface. Mars is a cold desert world with a thin atmosphere, polar ice caps, and evidence of past liquid water flows. It was the focus of extensive human exploration and rudimentary colonization efforts in the centuries before FTL travel, with several pressurized habitats and research stations still maintained by the UNSF and civilian entities, primarily for scientific research and as a proving ground for off-world habitation technologies.
Asteroid Belt
Located between the orbits of Mars and Jupiter (roughly 2.2 to 3.2 AU from Sol), this region is populated by millions of rocky bodies ranging in size from dust particles to the dwarf planet Ceres. While historically considered a navigational hazard, advancements in sensor technology and automated plotting allow safe transit. The belt holds significant potential for resource extraction (minerals, metals, water ice) which may become crucial as humanity's interstellar presence grows.
Outer Planets
Jupiter
The undisputed giant of the system, a massive gas giant primarily composed of hydrogen and helium. Its immense gravity significantly influences the orbits of other bodies. Known for its turbulent atmosphere featuring the Great Red Spot (a persistent anticyclonic storm centuries old) and a powerful magnetosphere. Jupiter possesses a large system of moons, including the four large Galilean moons (Io, Europa, Ganymede, Callisto), which have been targets of scientific interest for potential subsurface oceans (Europa, Ganymede) and unique geological activity (Io).
Saturn
The second-largest planet, another gas giant renowned for its spectacular and complex ring system composed mainly of ice particles. Like Jupiter, it has a large retinue of moons, including the sizable moon Titan, which possesses a dense, nitrogen-rich atmosphere and lakes of liquid methane/ethane, making it a unique environment within the system and a subject of ongoing scientific curiosity.
Uranus
An ice giant characterized by its featureless cyan appearance due to atmospheric methane absorbing red light. Uranus is unique for its extreme axial tilt (approximately 98 degrees), causing it to essentially orbit Sol on its side, leading to extreme seasonal variations during its long orbit. It possesses a faint ring system and numerous icy moons.
Neptune
The eighth and farthest known planet from Sol, Neptune is an ice giant similar in size and composition to Uranus but with a more vivid blue hue and visibly active weather patterns, including extremely high wind speeds. It also has a faint ring system and several moons, the largest being Triton, notable for its retrograde orbit and suspected cryovolcanic activity.
Trans-Neptunian Region
Scattered Disk (Kuiper Belt Analogue)
Extending beyond Neptune's orbit, this region is a vast reservoir of icy planetesimals, remnants from the Solar System's formation. It is significantly more populated than the Asteroid Belt, though its bodies are primarily composed of frozen volatiles like water, methane, and ammonia. The UNSF has cataloged numerous objects here, including established dwarf planets Pluto (once considered the ninth planet), Eris, Haumea, Makemake, and Sedna. UNSF Sensors typically categorize most objects found here simply as "Icy Bodies" during initial scans.
Oort cloud
The Oort Cloud represents the vast, gravitationally-bound outermost region of the Sol System. Based on extensive astronomical studies and gravitational modeling over centuries, its structure is understood as an immense, near-spherical shell surrounding the inner system at distances potentially reaching up to ~1.81 light-years (approximately half the Hill Radius). Though individual objects within the cloud remain sparsely distributed and challenging to observe directly even with 23rd-century technology, its existence and role as the primary reservoir for long-period comets entering the inner system are well-established scientific facts. It defines the practical limit of Sol's gravitational dominance against the wider galactic environment.
Exploration History
Pre-FTL
Prior to the development of the Alcubierre Drive, humanity spent centuries exploring the Sol System. Initial efforts involved robotic probes mapping the planets and moons, followed by crewed missions to Luna and Mars. Limited colonization and resource utilization began on Mars, and extensive infrastructure was established in Earth orbit and on the Moon. This Increased other the Decades and centauries with Technology's allowing space travel edging closer the the Speed of Light. This paved the way for Long term Missions to near by stars such as Alpha Centauri with some multi decadal one way missions. This era provided the fundamental knowledge of planetary science, spaceflight engineering, and long-duration habitation that proved essential for the subsequent leap to interstellar travel.
Early-FTL
With early testing of creating warp bubbles focus on FTL travel accelerated with early test ships breaking records and reaching Alpha Centauri in a matter of a couple of month. The designs were refined until the time was done to a matter of days then hours, once the travel time was fast/safe and efficient enough the UNSF commissioned plans for the first long mission with a new start ship that could realistically explore the vast void of space between starts around the milky-way.
Space Infrastructure (2261 AD)
As the hub of human activity, the Sol System possesses significant space infrastructure:
- Orbital Stations: Numerous large space stations in orbit around Earth and Luna serve various functions including scientific research, commercial activity, habitation, and UNSF fleet support. High orbit facilities often serve as construction and staging points for deep space vessels.
- Lunar Bases: Permanent scientific and industrial facilities exist on Earth's Moon.
- Martian Outposts: Established research bases and early colonial habitats persist on Mars.
- UNSF Facilities: Dedicated UNSF orbital docks, command centres (potentially including Fleet Headquarters on Earth or in orbit), and training facilities are concentrated within the system, particularly in Earth-Luna space.
- Navigational Network: A system of navigational beacons and communication relays throughout the inner system and extending to the outer planets to support interplanetary travel and communication.
- Deep Space Sensors: Arrays to monitor the system's periphery and provide early warnings or astronomical data.
Significance in the Interstellar Era
Despite the advent of FTL travel, the Sol System remains the political, economic, and military heart of human space. It is the most thoroughly surveyed and understood star system available to humanity, serving as a vital logistical hub, training ground, and command center for the United Nations Space Fleet. Missions departing for interstellar space via the Alcubierre Drive typically originate from designated points within the Sol System, often in high Earth orbit or beyond the densest regions of interplanetary traffic. Its well-known characteristics serve as a baseline against which all newly discovered systems are compared, highlighting the vast scale and myriad unknowns that await humanity in the galaxy beyond.