Transhumanity is not just a spacefaring race, it is also largely space-dwelling. While a substantial portion of transhumanity inhabits planetary bodies like Mars, Luna, Venus, and the moons of the gas giants, the balance live in a variety of space habitats, ranging from the old-fashioned O’Neill cylinders of the inner system to the Cole bubbles of the outer system.

Space Habitats

Space habitats come in many sizes and configurations, from survivalist outposts designed to support ten or fewer people to miniature worlds in resource-rich areas housing as many as ten million people. In heavily settled regions of space, such as Martian orbit, habitats may be integrated into local infrastructure, relying to some extent on supply shipments from other orbital installations.
More commonly, especially in the outer system, habitats are independent entities. This usually means that in addition to the main space station, the habitat is attended by a host of support structures, including zero-g factories, gas and volatiles refineries, foundries, defense satellites, and mining bases.
Habitats—especially large ones—sometimes have visitors, as well. Majors habitats are crossroads in space. In addition to scheduled bulk freighter stops, they may have hangers-on such as scum barges, prospectors, or out-of-work autonomous bot swarms.
Many habitats have some form of transportation network. This is most common in large cylindrical habitats with centrifugal gravity. Common solutions for public transit include monorail trains, trams, and dirigible skybuses. Common personal transit options included bicycles, scooters, motorcycles, and microlight aircraft, with larger vehicles being uncommon and usually reserved for official use.
Most habitats with large interior spaces also use augmented reality overlays to create consensual hallucinations of a sky and clouds, to which most residents keep their AR channels tuned. One would think that in space, talking about the weather would have disappeared from transhumanity’s repertoire of small talk, but the habit persists—only the weather discussed is usually virtual (if it’s not real “weather”—solar fare activity and the like).


Beehives are asteroids carved out with tunnels and chambers. They are commonly converted from asteroids mined for metals or silicates. Beehives are microgravity habitats and can be quite confusing to navigate without AR aids. Most beehives are found in the Main Belt or Trojan groupings. Most are small, but some have populations ranging into the millions, with massive cavernous microgravity cities.

Cluster Colony

Clusters are the most common form of microgravity habitat. Clusters consist of networks of spherical or rectangular modules made of light materials and connected by floatways. Typically business and residential modules are clustered around arterial floatways and infrastructure modules such as farms, power, and waste recycling. Limited artificial gravity areas may exist, frequently parks or other public places and specialized modules like resleeving facilities (morphs often keep better when stored in gravity). Arterial floatways in large clusters may have “fast lanes” where a constantly moving conveyor of grab-loops speeds people along.
Clusters are most commonly found in volatile-rich environments like the Trojans and the ring systems of the gas giants (particularly Saturn). Clusters are rare in the Jovian system because shielding a cluster of individual modules rather than one large station from Jupiter’s intense magnetosphere is hideously inefficient.
Cluster colonies can have anywhere from 50 to 250,000 inhabitants.

Cole Bubbles

Cole bubbles (or “bubbleworlds”) are found mostly in the main asteroid belt, where the large nickel-iron asteroids used to construct them are abundant. Bubbleworlds are less common in the Trojans and Greeks, where crusty ice asteroids predominate. A Cole bubble is similar in many respects to an O’Neill cylinder, but there are no longitudinal windows. Sunlight instead enters through axial mirror arrays. Cole bubbles can also be spun for gravity, according to the whims of the inhabitants, though the gravity lowers as you near the poles of the bubble, with zero gravity at the axis of rotation. Cole bubbles are among the largest structures transhumanity has created in space, hosting populations in the millions.

Hamilton Cylinders

Hamilton cylinders are a new technology. There are only three fully operational Hamilton cylinders in the system, but the design shows great promise and is likely to be widely adopted over the coming period. Hamilton cylinders are grown using a complex genomic algorithm that orchestrates nanoscale building machines. These nanobots build the habitat slowly over time, a process more like growing than construction.
Similar to O’Neill cylinders and Cole bubbles, a Hamilton cylinder is a cylindrical habitat rotating on its long axis to provide gravity. Two of the known Hamilton cylinders orbit Saturn in positions skimming the rings near the Cassini division. From this position, they can graze on silicates and volatiles using harvester ships.
None of the currently operating Hamilton cylinders have grown to full size yet, but estimates say they could each house up to 3 million people.

O'Neill Cylinders

Found mostly in the orbits of Earth, Luna, Venus, and Mars, O’Neill cylinders were among transhumanity’s first large space habitat designs. O’Neill cylinders are no longer built, having been replaced by more efficient designs, but are still home to tens of millions of transhumans. O’Neill cylinders were constructed from metals mined on Luna or Mercury, Lunar volatiles (including Lunar polar ice), and asteroidal silicates.
A typical O’Neill habitat is thirty-five kilometers long, eight kilometers in diameter, and rotates around its long axis at a speed sufficient for centrifugal force to create one Earth gravity on the inner wall of the cylinder. Smaller cylinders exist, though these usually feature lower gravity (typically Mars standard).
Cylinders are sometimes joined together, end-to-end, for extra long habitats. A spaceport is situated at one end on the rotational axis of the cylinder (where there is no gravity). Arrivals by space use a lift or microlight launch pad to get down to the habitat floor. The inside of an O’Neill cylinder has six alternating strips of ground and window running from one cap of the cylinder to the other. One narrow end of an O’Neill cylinder points toward the sun. The opposite end is the mooring point for three immense reflectors angled to reflect sunlight into the windows. Smart materials coating the windows and reflectors prevent fluctuations in solar activity from delivering too much heat. The air inside the cylinder and its metal superstructure provide radiation shielding.
The land in most O’Neill cylinders is one-third agricultural (a combination of food vats and high-yield photosynthetic crops), one-third park land, and one-third mixed use residential and business. O’Neill habitats have a day and night cycle regulated by the position of the external mirrors. The business and residential sections of the cylinder usually alternate with the park land over two of the strips of land; cropland usually takes up the third. Bridges cross the windows every kilometer or so, linking the land strips. The interior climate, the architectural style of the structures, and the types of vegetation and fauna present vary with the tastes of the habitats’ designers.
Depending upon size, O’Neill cylinders can house from 25,000 to 2 million people.

Tin Cans

Antique research stations and survivalist prospector outposts often fit this description. Tin can habitats are only a few notches up from the early 21st-century International Space Station. Tin cans usually consist of one or more modules connected to solar panels and other utilities by an open truss. Deluxe models feature actual floatways or crawlways between modules, while barebones setups require a vacsuit or vac-resistant morph to go from room to room. Food growing capacity is severely limited and there may be no farcasters, but fabricators are available, as well as mooring for shuttles and perhaps prospecting craft. Tin cans rarely house more than 50 people.


Interchangeably called toruses, toroids, donuts, and wheels, these circular space habitats were a cheap alternative to the O’Neill cylinder used for smaller installations. Like O’Neill cylinders, toruses are seldom constructed anymore, but many are still encountered in the inner system, particularly in Earth and Lunar orbit.
A toroidal habitat looks like a donut 1 kilometer in diameter, rotating on great spokes. There is a zero-g spaceport at the wheel’s hub. Visitors take a lift down one of the spokes to the level of the donut, where rotation creates one Earth gravity.
The plan of toroidal habitats varies greatly, as many were designed for specific scientific or military purposes and only later taken over as habitats by entrepreneurs or squatters. Many have a succession of decks in the donut. Most of those designed for long-term self-sufficient habitation have smart material-covered glass windows for growing plants along much of the inside surface of the torus. Toroidal habitats equipped for farming normally face the sun in a direction perpendicular to their rotational axis, but then use a slow processional wobble of that axis to create a day/night cycle.
Toruses were usually built to accommodate small crews of 500 or fewer people, though some larger ones exist, able to house 50,000. A few rare double toruses also exist, like two large wheels spinning in opposite directions, joined at the axis.

Immigration and Customs

How characters gain entry to a habitat and what type of screening they’re likely to undergo depends upon how they arrive. Some habitats are close to other settlements, while others are physically isolated by the vast, empty distances of interplanetary space. Habitats in dense planetary systems receive most of their visitors via conventional space travel. Immigration and customs infrastructure is geared toward receiving visitors via their spaceport, and the processing of arrivals is in most ways analogous to a twentieth century airport. Isolated habitats, on the other hand, tend to receive almost all of their visitors via egocast.

Physical Arrivals

Arrivals by spacecraft undergo, at minimum, an ego ID check, scans to detect pathogens, hostile nanobots, explosives, or radiation, and an inspection of their personal effects. Some habitats go farther, including rigorous secondary screenings using scout nanoswarms, scans of all electronic systems for malware, and/or aggressive interrogation of a fork of the subject. Even autonomist enclaves enforce automated scans for anything that might pose a danger to the habitat or any signs of hypercorp saboteur efforts.
Restricted goods vary according to local legalities. Many habitats, particularly those controlled by autonomist or criminal factions, allow personal weaponry as long as its nothing you can use to blow a hole in the structure or indiscriminately kill dozens of people. Others, notably the Jovian Republicand hypercorp stations, disallow lethal weapons of all kinds, except for people who have acquired special permits and authorization (sometimes available by bribing the right people or pulling favors with rep). Nonlethal weapons are generally allowed. Other restricted items may include nanofabricators, nanoswarms, malware and hacker software, drugs and narcoalgorithms, certain types of XP recordings, covert operations tools, and so on. Certain types of morphs may also be restricted, such as reapers, furies, or uplifts.
Certain habitats may insist that visitors—or at least the ones they don’t like the looks of—submit to specific forms of monitoring or surveillance for the duration of their stay. This might include taggant nanoswarms, hosting a police AI in your mesh inserts, or even physical tailing by an armed security drone.
Other stations will require that their visitors leave a fork as a form of collateral at the door—in case they commit a crime, the fork can be interrogated. Finally, though rare, some habitats go so far as to charge all visitors an “air tax”—a fee for using the station’s publicly available resources while they are present. This is generally only common in isolated habitats with strained resources, and is considered especially obnoxious by most autonomists. Some syndicates run a good business in smuggling certain goods or even people into habitats. This is generally accomplished through bribed security personnel, but is also sometimes handled as falsified credentials that will allow the subject to breeze past security checks. Such services are typically quite expensive. For those hoping to gain quiet and unobserved access, there is always the option of taking a spacewalk and trying to break in through an unattended airlock. Such attempts are quite often dangerous and futile, as most habitats have dedicated sensor and security systems to monitor their exterior surface and in particular any access points. Still, it is a possibility for a resourceful team with a skilled hacker, though armed sentry bots are a particular danger.

Electronic Arrivals

Arrivals by egocast are sometimes interviewed by habitat authorities in a simulspace before resleeving. Depending upon the habitat’s attitude toward civil rights, this process can be relatively reasonable or quite invasive. A minimal entry inspection includes an ID check, a brief interview with a customs AI, and a review of the specs of the morph into which the arriving ego plans to resleeve. Habitats with draconian immigration measures may use harsh psychosurgery interrogation techniques on suspect infomorphs. Egocast backups have little recourse to avoid this treatment—station authorities can simply file them away in cold storage if they choose—so it is wise to investigate custom procedures before you send yourself over.
Because many people, particularly autonomists and brinkers, don’t appreciate this kind of reception, various uploading services have stepped in to provide pre-customs resleeving for characters traveling to habitats with suspect screening methods. For often-exorbitant fees, the traveler egocasts into an extraterritorial substation close to their intended destination, resleeves there, and then travels to their destination by rocket.
Various darkcast services, normally run by established crime syndicates, sometimes offer an alternative method of egocasting in and possibly even resleeving. Darkcast services are quite expensive, however, and the character is at the mercy of the syndicate operators. In rare cases, some political factions or even hypercorps might operate their own darkcast systems, which a character with good networking skills might be able to take advantage of.

Space Travel

In some circumstances, characters will prefer to travel physically through space rather than egocasting. In Eclipse Phase, spacecraft are primarily dealt with as a setting environment rather than a vehicle/gear to use. Spacecraft largely pilot themselves via the onboard AI. Though characters can also take over with their Pilot: Spacecraft skill, the situation rarely calls for it.

Local Travel

In densely inhabited planetary systems such as Mars and Saturn, most travel between cities, surface stations, and orbital habitats within 200,000 kilometers is by small hydrogen-fueled (or sometimes methane-fueled) rockets. This form of travel is incredibly cheap, very fast, and avoids the occasional personality glitches that crop up during egocasting. LLOTVs (lander and orbital transfer vehicles) are commonly used. Spacecraft leaving a planetary body need to be able to generate enough thrust to escape the gravity well.

Distance Travel

For distances of 200,000 to 1.5 million kilometers, somewhat larger (and more expensive) fusion- and plasma-drive craft make regular runs. Nuclear electric ion drives were once used on some of these routes, but the poor efficiency of these fission systems and the need for radioactive heavy metal reaction mass means that they are almost never used anymore. Faster anti-matter-drive couriers are also commonly used. These ships lack the thrust to escape from the gravity wells of large planets or moons, so they station themselves in orbit and use smaller ships (typically LOTVs) with higher thrust to transport people to and from the planetary surface.
For distances beyond 1.5 million kilometers, almost everyone uses egocasting

Space Travel Basics

Spacecraft use various types of reaction drives, meaning that they burn fuel (reaction mass) and direct the heated output in one direction, which pushes the spacecraft in the opposite direction. Travel over any major distance typically involves a period of high-acceleration burn for several hours at the beginning of the fight, where up to half of the reaction mass is spent to drive up the craft’s velocity. The ship then coasts for the majority of the fight at that speed, until it approaches its destination, where it flips over and burns an equal amount of reaction mass in the opposite direction to decrease velocity.
Though some craft burn half their reaction mass to get up to the best speed possible, this doesn’t leave much room for additional maneuvering or emergencies. Many craft therefore only burn up to a quarter or a third of their fuel in initial accelerations, so they have some to spare in case they need it. A few tricks can be used to save fuel and build speed, such as sling-shotting around the gravity wells of larger planets or aerobraking in a planet’s upper atmosphere.
Travel times between locations are constantly changing as various bodies move in their orbits around the solar system. Within a cluster or planetary system, travel takes a matter of hours. Within the inner system, travel can take days or weeks. Travel to, from, or within the outer system can take much longer, and is usually a matter of several months.
Most ships operate at zero g, except for a few larger craft that are able to spin habitat modules for low gravity. Periods of high acceleration also produce temporary gravity in a downward direction, towards the burn. Space is a valuable commodity on board spacecraft, so room is often tight. Sleeping and personal quarters are rarely bigger than large closets, just enough room for a sleeping bag and personal effects. Depending on the size of the craft, there may be a communal recreation area. The crew tend to only be busy at the beginning and end of a trip, when they must deal with acceleration/deceleration and maneuvering around other space traffic. The rest of the trip they spend dealing with repairs or otherwise killing time, often by accessing XP or VR simulations or playing AR games. While spacecraft have their own local mesh network, they are usually too far to interact with the mesh networks of other habitats without significant communications lag, so they must make do with their own archive of entertainment options. Many long-haul ships are crewed by hibernoid morphs, who hunker down for a long nap.

Spaceship Combat

Combat in space tends to take place over long distances using massive beam weapons, railguns, and missiles. It also tends to be nasty, brutish, and short. Significant damage to a vessel can cause atmospheric decompression, killing any biomorph crew who aren’t suited up and strapped down.
For the most part, it is recommended that space combat be treated as a plot device, part of the background story that helps create drama and tension, rather than an event that characters actively participate in. This is not to say the characters cannot play a role in the combat or that their actions will have no effect on the outcome. They may become involved in damage control, negotiate with hostile forces, repel boarders, target weapons with Gunnery skill, stage a mutiny, attempt to hack the networks of approaching vessels, escape out the airlock, hide out while the pirates sack the ship, or similar affairs. It is recommended, however, that gamemasters steer clear of space combat situations that could easily lead to the whole team dying due to a few bad dice rolls.

Community content is available under CC-BY-SA unless otherwise noted.