Copyright © 1986-1999 by Andy Slack. All Rights Reserved.
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Like most SF RPGs, plain vanilla 2300AD assumes that almost all of mankind's colonies will be set up on planets, and space is just for travelling through. An alternative assumption is that planets are not the best places for a technical civilisation. They have uncontrolled weather with extremes of temperature; their atmospheres make it hard to make a good vacuum or collect solar power; you have to take the terrain as you find it; the gravity makes it difficult and expensive to get on and off them, and interferes with construction and transport.
In my 2300AD universe, the Solar System is teeming with orbital colonies;
this matches my view of the future, which is heavily influenced by C J
Cherryh's Alliance and Union stories, such as Merchanter's Luck and Downbelow
Station. Your Mileage May Vary.
It can be any shape that will hold air, and the smaller ones have many different shapes. The typical large colony is a cylinder up to 6 km across and 30 km long, rotating every two minutes or so to provide artificial gravity. The cylinder is divided into long strips down its length; three immense glass windows, strengthened with cables, alternating with three strips of land. Each window has a mirror outside to reflect sunlight onto the strip of land opposite. Manufacturing facilities are on the sunward end of the cylinder, and huddling around them is a ring of small agricultural cylinders housing the colony's farms.
Since they rotate, gyroscopic effects prevent single main cylinders from being continuously aimed at the sun, so a large free-floating secondary mirror would be needed to reflect the sun's rays onto the colony for light, warmth and power. So, most colonies have counter-rotating pairs of cylinders with no secondary mirror -- such a pair has no net spin and so can track the sun easily.
Colony cylinders are made by vacuum-vapour deposition; a plastic balloon several kilometres across is rotated slowly past a solar furnace which sprays aluminium vapour onto it. The metal condenses to form a seamless metal shell, as thick as you like. Due to the colonies' low population, most routine assembly work is done by robots, with the humans along mainly as troubleshooters. To make life easier for the machines who do most of the work, the fittings are built from modular fabricated sections, so they all tend to look alike inside.
Colonies spin to provide simulated gravity not just for comfort and convenience, but also to avoid loss of calcium from the colonists' bones, which would make them more fragile. The rotation rate is usually one rpm or less, as if the spin is faster, workers commuting daily between the zero-G industries around the colony and the simulated gravity inside suffer from motion sickness. The twin constraints of maximum rotation rate and minimum gravity define the colony's size; depending on which medical consultants the builders took advice from, the rotation rate can be up to 3 rpm and the simulated gravity can be anything from 0.1 G up. Pregnant women and young children are housed in more Earth-normal gravity than adults; scientific, mining or military stations thus tend to have lower gravity than those with large civilian populations.
Colonies or bases on the surfaces of the Moon, Io etc. consist
of bunker-like structures covered with local soil and kept in permanent
shadow by sunscreens to help control their temperatures -- it is much easier
to heat a room than to cool it, and this is particularly true in vacuum.
The main industry of the first orbital colonies was building solar power satellites to beam power down to Earth, and they have retained a heavy reliance on solar power -- it's cheap, easy to collect, and has no waste products to speak of. Orbital colonies are usually set far enough out from the worlds they orbit that they very rarely go into shadow, so that they can collect as much sunlight as they need. The two main methods used are vast arrays of solar cells, or mirrors focussing the sunlight to boil a working fluid which turns turbines, which in turn spin generators. In either case, the further out from the sun the colony is, the weaker the sun's rays, and so the larger and more elaborate its solar arrays.
Surface colonies experience regular nights and so cannot depend entirely
on solar power; they rely on other means of power production at least part
of the time. These may be fission, fusion or MHD plants; fission
plants are the rarest because the only significant supplies of uranium
or plutonium in the Solar System are on Earth, and it is expensive to haul
them up out of the gravity well.
Mining among the Solar System colonies means either opencast surface mines on moons, or asteroid mining. Asteroids have only 10% as much aluminium and titanium as lunar soil, so the Moon's main exports are ores rich in those two metals.
The Moon mines were established first -- as a source of raw materials for building powersats -- and are still the most productive. Lunar mines produce aluminium, titanium, iron and silica ( used to produce fibreglass); another product of major importance is oxygen, which is chemically bound to the metals and the silicon and represents about 40% of the rocks' composition. Lesser but still useful constituents of lunar rock include hydrogen, nitrogen, carbon, sulphur and sodium.
The ore is refined on the Moon or in nearby colonies, since shipping refined metals is cheaper than shipping bulky unrefined ore. Since everything must be recycled, and water is in short supply, refining uses complex and costly chemical processes.
The asteroids have much more iron and several times as much magnesium as lunar soil, so their miners concentrate on those metals. Further, the asteroids known as chondrites have high proportions of water and organic chemicals, so originally most of these items were mined in the asteroid belt -- with stutterwarp vessels, it was cheaper to get organics from the Belt than to ship them up from Earth, although since the Beanstalk was completed the Belters have faced serious competition from Earth corporations. The asteroids began to be exploited later than the Moon because they are several hundred times farther from Earth and have orbits which require more delta-V to match; so, asteroid mining needs ships with better propulsion and life-support systems, which weren't developed until later on. Asteroid and planetoid orbits are widely variable, and one of the main practical purposes of Astronomy skill in the game is the search for asteroids with valuable resources which are in a convenient orbit for exploitation by a given colony.
Iron and stony-iron asteroids contain iron ( surprise!), often alloyed with nickel and ready for the rolling mill; the large asteroid Psyche, for example, is more or less solid nickel steel. The easy way to mine this type of asteroid is to spin it using explosives, and melt the whole asteroid with sunlight focussed by mirrors; the various constituents separate out into layers under centrifugal force and are scooped off as needed. Sometimes heavier metals than iron are found, but these are rare.
Carbonaceous chondrites are very dark, having about 7% carbon and up to 20% water; they have about half the organic compound content of oil shale, mostly in heavy hydrocarbons like waxes and oils; they are much sought after for plastics feedstocks as well as their water. Ceres and Pallas are large asteroids of this type, which is the most common. They are mined by automated chemical plants on their surfaces, powered by solar energy, which extract water and organics from the asteroid and process the latter into fertilisers, plastics and so on, as well as extracting the few nitrogen compounds present. The water can be electrolysed to yield oxygen and hydrogen, both of which have many uses.
As well as providing mineral resources, the asteroid belt is the Solar System's frontier. There are millions of small asteroids, each capable of supporting a small group who can afford the few tens of thousands of Livres for the equipment needed to homestead it. The Belt is so large as to be effectively ungovernable, so those who like solitude or dislike authority can vanish into it. However, the belt has no law to speak of, and should any of your equipment fail, it won't matter how good the manufacturer's guarantee is...
The moons of the outer planets also have extensive mining facilities.
Most of the smaller moons' mining operations can be treated for game purposes
as if they were on asteroids; larger moons usually specialise in extracting
water and oxygen from surface ice. However, there are exceptions,
for example Io has large sulphur deposits which are extracted to make the
sulphuric acid vital for many industrial processes.
The average colonist needs around 5 kg of food, water and oxygen per day. Much of this is recycled; even so, farms are present because of the high cost of shipping food up from Earth. Fortunately, farming is easy in space because there are no pests, no weeds, and the weather does what it's told.
Oxygen is produced by plants in the farming modules and the main colony, which also extract the carbon dioxide from the colony's air. There are so many plants in the average colony that no more elaborate method of recycling the air is needed. Atmospheric pressure is one-half an Earth atmosphere, which is enough pressure for physiological needs -- higher pressures mean thicker, more expensive walls, and worse damage from punctures. The air is about 40% oxygen, with almost all the rest being nitrogen for the plants and to reduce fire hazards. Even so, fire is a serious hazard, more feared for its consumption of oxygen than its actual damage; probably only major punctures cause more nightmares. The humidity is around 40%, except in farm areas and grain storage. The air temperature is about 22 degrees Centigrade. Waste gasses are adsorbed on activated charcoal filters and then sent to the waste processing plant. However, only in the largest colonies are there blue skies ( which need air at least three kilometres thick to form) and natural clouds.
The bulk of the water in the colony's atmosphere is given off by plants; this is recycled by dehumidifiers in the farming modules. The water passes through no ground strata and has no chemicals or dissolved salts, so it is extracted from the air and piped straight to peoples' homes. Water is also produced as a byproduct of small power plants, where fuel cells combine hydrogen and oxygen to produce water and energy ( most internal station vehicles are powered in this way).
Food is produced in small farm units orbiting the main colonies. The main reason for not farming inside the colonies is the 24 hour lighting, high ventilation, and high humidity used for optimum plant growth. Interplanting is used, so that at any time in a plot there are some crops being planted, some growing, some ripening, and others being harvested, all mingled together. A typical sequence would grow rice, sweet potatoes, soybeans, corn, and then soybeans again. The stems and cuttings are fed to livestock. As well as food plants cotton is grown, for use in clothes and paper.
Plants are grown on styrofoam boards for support, with nutrients and water sprayed directly onto their roots. This eliminates the need for expensive, heavy topsoil and makes it easy to harvest roots for animal feed. Since hand-pollination of vegetables is very boring, the colony usually has several hives of bees selected for their docility. These produce honey as a by-product.
Meat is relatively scarce; meat animals take up a lot of room and food for the meat they produce, and much of what cows, pigs and chickens eat can be eaten directly by people. The staple meat in most colonies is rabbit -- mild-flavoured, low in fat, and easily cooked. The farms produce alfalfa, a perfect rabbit food when salt is added. Each doe rabbit and her litter takes up about one square metre and her alfalfa patch about twelve times as much room. The total yield of boneless meat from this sort of set-up is about 150 kg per hectare per day.
The waste stems, leaves and roots are converted into milk and other dairy products by ruminants, usually cows or goats. Goats are common, since they eat 10% as much as a cow but produce 25% of the milk; in the average colony as much as two litres of goats' milk per person is available each day. Chickens are fed kitchen waste and the leftovers from rabbit butchering, and provide 3-4 eggs per person per week.
Finally, there are fish. These are nearly as productive as rabbits where protein is concerned, and colonists can get up to 300 grammes of fish fillets per week each. Now fish out of water in a gravity field die because their gills collapse, which stops them getting any oxygen; in zero-G hydroponic fish-farming, the fish are left floating in mid-air in an atmosphere of 100% humidity. ( In real life, ponds in the farms will be more practical; but free-flying fish give more of a sense of 'being there' in the future, and imagine the fun you can have refereeing a zero-G firefight in a room with 100% humidity full of flying fish...)
The average farm yield runs at about 950 kg/hectare per day, so every hectare of farmland can support about 250 colonists; once you have decided the population, that tells you how big a colony's farms are. There are a few professional farmers and agronomists, but most of the farm staff are volunteers who work there a few hours each week in their leisure time.
As well as the farms, the main cylinder has trees for fruit, for shade, and just to look cool. These provide apples, oranges, pears, plums, cherries and peaches; more adventurous colonies grow coconuts and bananas. Some colonists have their own gardens for flowers and vegetables.
The food never has to travel more than a couple of kilometres to market, so there is no spoilage in transit and no need to add preservatives. There are no supermarkets full of packaged goods; the food market is a group of farmers' stalls with bins full of fresh produce and the odd refrigerator, looking a lot like a pre-industrial farmer's market or bazaar. Naturally, anywhere you have fruit or grain and some enterprising individuals, you have alcohol shortly thereafter...
Sewage is heated with oxygen in high-temperature, high-pressure conditions
for an hour and a half, producing sterile water with ammonia and phospate
ash, and a gas rich in carbon dioxide. The phosphate ash and gas
are sent to the farms to help in growing plants. Water is purified
and recycled.
The colonial environment is cramped and artificial, but it can still be pleasant to live in. The buildings are closely-spaced and only a few stories high, with plenty of trees and other greenery. They are assembled from prefabricated, modular wall sections. However, within this constraint, the occupants strive for diversity.
Apartments have simple, open designs, with a structural defined by metal girders. As the walls are not load-bearing, they can be swapped as desired for floor-to-ceiling plate glass windows. Floor panels are lightweight honeycomb, and ceiling panels may be clear, coloured or opaque according to taste; most are opaque, because only a few kilometres away other people are living over your head, and they may have telescopes...
Living rooms are in the corners of the building, with two glass walls. Neither heating nor cooling is a problem, as the entire colony is 'air-conditioned'. The land area available per person is only about 50 square metres; builders deal with this shortage of space by hiding it. The colonists live in small clusters of houses, each with some focus such as a courtyard fountain or stand of trees, so that people are aware only of a few neighbouring houses. The problem is made easier by the almost total lack of cars and trucks; most movement is on foot or by bicycle, with subways or monorails for longer-distance travel. Quite often houses are terraced so that one man's roof is his neighbour's lawn.
Scattered among the houses are public parks and gardens, with small lakes that serve as water reservoirs as well as recreational areas and homes for ducks, which have aesthetic, psychological and nutritional value. Speaking of the latter, ovens are microwave or electric -- electric power is plentiful, but fuel for burning is not.
Plastic is not widely used, because it must be made from hydrocarbons,
which originally were very scarce in space; although they are plentiful
since the exploitation of the asteroids and the widespread use of the stutterwarp,
spacer tradition decrees other materials. What the builders have
always had in plenty are aluminium, titanium, steel and glass. Bricks
and concrete are made from planetary soil so they are greyish-white.
As they are made primarily of steel, concrete and glass the colonists'
homes are durable and sturdy structures. Furniture and decorations
are made from aluminium and ceramics; the trees are too valuable alive
to be used for wood. Fabrics are made from woven glass fibre and
are about the consistency of denim; they won't absorb dye, but can be made
of stained glass, so colours are mostly blues, reds, purples, greens and
browns, and glow irridescently in the sun. Stains wipe off easily
with a damp sponge, and the fabrics are fireproof.
Anything tough and durable, like overalls, is made of the same woven fiberglass
as the furniture coverings and curtains. Softer, lighter clothes
are made from locally-grown cotton, dyed in the usual way, and usually
recycled. Due to the small populations of the colonies, the services
they provide are limited, and professional tailors and dressmakers are
rare; so many people who want something distinctive make it themselves,
or enlist a friend or relative. This is less true in the larger stations.
As mentioned earlier, trees are just too valuable to chop down. This makes paper very rare; it is jealously guarded and carefully recycled. Notepads, diaries, and most books are replaced by portacomp chips. Paper ( and plastic) bags are replaced by the ubiquitous woven fibreglass. Financial transactions are made by credit card or electronic fund transfer, so there is little need for paper money.
All of this need not cramp the style of referee or player much.
After all, there is no paper at all in the Star Wars universe and
that doesn't slow down the adventures. PCs should be aware, though,
that using a lot of paper is a sign of wealth.
Virtually the whole range of team and individual sports is practiced, and home entertainments include all kinds of music and video. Due to the low gravity, though, there are some recreations unknown before spaceflight.
These include zero-G swimming, basketball, darts etc. in the microgravity areas near the axis of rotation. Zero-G waterball fights replace planetary snowball fights, and walking on water takes a long time to lose its appeal.
There are also a few pursuits that are not available. Anything
involving hunting, or lots of large animals ( like horse-racing) is too
expensive in terms of floor area and life support.
The whole colony is designed to encourage community spirit, and as the inhabitants depend on each other for continued survival, they form very close-knit communities. Further, they are accustomed to discipline and obeying orders, because that is sometimes necessary for survival in space. Paradoxically, the need to solve problems quickly or die also breeds independence and self-sufficiency.
Space is an unforgiving environment, and colony populations are small; so the average colonist is over-protective of women and children. The small populations make for a shortage of skilled people, and so education and training start at an early age; almost everyone has Mechanical or Electronic skill, as their lives depend on machines.
The person in charge of the colony, whatever his title, however appointed, and however benevolent, is a despot with absolute power of life and death over the colony due to the centralised control of life-support systems -- and absolute power corrupts absolutely, which can geneerate many adventure scenarios.
The only animals the average colonist has met are domesticated species,
as colonies only have animals which can pay their way in meat, milk, or
companionship. Should an orbital colonist meet a hungry bear, for
instance, since his upbringing will have stressed teddy bears and cartoon
bears, he may not demonstrate the respect due to something as large and
dangerous as a grizzly. A 'wild' animal, especially if exotic in
some way, is a status symbol for the very rich.
July 1998: KevinC emailed me to point out that I wasn't allowing enough water for industrial processes, and right he was. So all of my colonies have just sprouted huge internal lakes...