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Out of the Wind: Sealed Habitats

This article originally appeared in the March/April 2019 issue.

“Landing pad 14c. Roger that.” I couldn’t miss the markers, the tree must have been a mile high. At least the rain slackened off somewhat once I’d manoeuvred the ship under the shelter of a canopy that deceptively made me feel like I’d shrunk tenfold. Wind sheer made it a difficult landing although large vertical sheets of fungal growths acted as baffles which helped. They seemed to have grown up in remarkably helpful configurations. I hit the mark and we settled down under a vast root. The Captain lifted a hand that had been clenched on restraining webs and gave me a thumbs up from her crash couch. “Well done.” She almost smiled. A ‘welcome to Namankaza’ appeared on my flight screen from a diminutive Lieutenant Svamp.

Locals, none of them taller than waist height, could be glimpsed swarming across the top of the root as we’d come in. Now they were lowering a vast sheet over the edge. As it rolled downwards towards the ground and sealed us into what now amounted to a natural hanger, I could see the sheet looked like nothing so much as a multitude of large leaves sewn together. I say sewn; I couldn’t actually see any stitching. More remarkably still, it wasn’t long before my console notified me that the atmosphere around the ship was now breathable although the temperature and humidity were high.

We stepped out onto a strange spongy surface and headed towards an airlock. There was a damp, earthy smell. The airlock was built into a blister that was barely as tall as I was and given the dimensions of the natives, was clearly for the benefit of visiting travellers. Once through the ’lock, a corridor spiralled downwards and we could see that the walls and ceiling were the same material as the floor. Soft-textured, spongy, parti-coloured but predominantly muted browns and sickly whites. I poked my finger at a spot to see it give just a little and then firmly resist.

I’d heard of the fungal caverns of Namankaza but seeing them, well, in the flesh I suppose, was a different locker of luugiirs altogether. We arrived at a small customs hall and there was no change in the surfaces that enclosed us. The smell seemed to have thickened. Not unpleasant; just heavy going. We were well inside the fungus now and a map I’d downloaded suggested that big as the structures we’d seen on the surface looked, they were nothing compared to the city itself.

“Welcome to Starport Houba,” said a local sitting on a tall stool that put his large bright eyes at my level. His smile was infectious and I found myself grinning back. “Have you anything to declare?” he asked. The Captain presented a list of the prescribed items which got a careful once over. Fortunately, I was the only one to hear Peet mutter from the back of our group, “nothing, ’cept I don’t think I’m going to prepare the mushroom risotto I was planning for tonight’s meal”.

Travellers will encounter myriad ways in which people and societies arrange their environments and living space. They will also encounter large numbers of worlds which don’t have atmospheres conducive to human life. Getting out of the weather or out of the vacuum will be crucial on many worlds. In the absence of bioengineering humans to live in non-standard environments, such worlds will have enclosed spaces to support life. They may be tiny pressurized shelters of early colonists, or vast structures that dominate the landscape. And of course all space habitats will be ‘enclosed’ in this way.

For all the possibilities of Charted Space, it can be all too easy for adventures to fall into assuming that one port or planet is much the same as the last one – and that may be true to a certain extent, particularly within fairly homogenized cultures. Technology designed by a culture tends towards similar patterns and costs are reduced by standardization. However, that doesn’t mean that everywhere is going to be the same.

This article offers a variety of suggestions to get the creative juices flowing although it doesn’t suggest that all of the options given are equally likely. Some may be considered much less common in Third-Imperium-style Traveller universes, for example, and can be ignored or re-rolled. This list is still humanocentric however, and Referees might wish to include much stranger options. It is hoped that this will give inspiration to Referees describing yet another stop off or to players looking for ideas as to the origins of their characters. Referees might allow a DM +1 to task checks such as Streetwise or Recon for characters whose background shows they come from a similar set up. Despite the rather fanciful title of this article, many habitations may be in a vacuum which doesn’t actually have any wind to escape and some structures might be large enough to contain wind patterns of their own.

Note that none of the options suggest an actual architectural style or the shape of these structures which can be a further source of differentiating results that the Referee can use for atmosphere or adventure seeds.

Although the primary focus of the enclosed habitat table is to provide options for populations that need to be completely isolated from an otherwise uninhabitable local environment, it can also be used for situations where the local environment is inhabitable but at some extreme that would make it uncomfortable or worse. Alternatively, it might be used where it’s necessary to protect the environment from the inhabitants for some reason – scientific, ecological, religious, etc. As ever, these are suggestions for inspiration rather than prescriptive rules.

Predominant Size of ‘Communities’

The predominant size doesn’t preclude other types existing on any given world. You may wish to roll on this table after rolling on Table 2 if you’d prefer to have the type of enclosed habitat inform the predominant size. Either way, there may be combinations that don’t fit the Referee’s idea of what is required and results should be adjusted accordingly.

Table 1: Predominant Size of ‘Community’
D6 Size of ‘Community’
0 Dwelling
1 Multiple linked dwellings
2 Outpost or Village
3 Town
4-5 City
6 Megacity
7 World city

DM –2 if POP 5– or GOV 0
DM –4 if POP 3–
DM +1 if POP 8+
DM +1 if SIZ 3– and POP 7+

Dwellings: these are homes for individuals or extended family units. They may be differentiated not just in size from a town or city, but in also having ‘exterior’ buildings, e.g., greenhouses, power generation, etc. In other words, you will need to dress appropriately for the environment: anything from serious cold weather gear through respirators to full vacc suits, in order to get to the external buildings. There may be local reasons why this is necessary or simply tech level or costs mean that connector structures haven’t been built yet. One example might be a new or struggling settlement where the ships or (cutter modules) the colonists arrived in serve as dwellings, but external ‘barns’ have been constructed to house livestock.

Multiple linked dwellings: these consist of several families, or other small social units (perhaps research teams or early colonists), situated in close proximity and linked to each other via tunnels, tubes or other airtight corridors. There will almost certainly be airlocks into and out of the connections and it would be good practice to don protective clothing such as respirators or vacc suits even if they’re not used except in emergency. The dwellings may have grown together from separate structures or have been designed that way for privacy or other cultural reasons, or due to resource allocation or local terrain requirements and so on.

Outpost or village: a tighter community than ‘multiple linked dwellings’, this can be seen as a single unified ‘building’ with entry points to a shirt-sleeve environment that don’t require outdoor weather gear to move between sections – although there may be internal airlocks for safety reasons. The designation outpost or village depends on the function of the (original) settlement – either a ‘mission’ of some kind (military, merchant, communications, religious, etc.) or a more ad hoc community development.

Towns and cities may be demarcated by size, density, number of dwellings, government presence, economic function, infrastructure levels, or some other physical or social marker such as whether or not they have a cathedral (as is often thought to be the case in the United Kingdom); it may simply be a grant by the ruler of the world or territory (as is actually the case in the UK). City status may or may not confer any actual privileges or responsibilities.

One way of defining city sizes for Traveller is to consider the Universal World Profile population digit -1 as a large city, UWP pop-2 as a medium large city, UWP pop-3 as a moderate city, UWP pop-4 as a small city and UWP pop-5 as a very small city. Obviously, this is a relative measurement, and may not work well where the world’s population is either extremely high or extremely low. Alternatively, set numerical values such as pop<1000 is a village, pop <50,000 is a town, pop<1,000,000 is a small city, pop <10,000,000 is a city, pop<50,000,000 is a large city.

A megacity may be defined as an urban conglomeration of 50 million people or more. Where a megacity holds essentially the entire population of the world, or its physical infrastructure covers the entire world or its land area, it may be called a world city. World cities’ size equals a world’s UWP population digit.

Other alternatives for defining a community’s size could also be used and may inspire adventure ideas such as some artefact being needed by the city’s burghers in order to gain city status, or perhaps the PCs are approached to be neutral representatives pleading the case for city status to the local (or not so local) ruler, or merchants can get more favourable trade deals by visiting ‘not quite cities’ because the government wants to encourage growth (thus getting the characters out of the starport and into the hinterlands for yet more adventure!).

Type of Habitation

Roll D66 on Table 2 to determine the type of habitation. This table provides ideas for the physical structure of the community, its physical location (e.g., land, sea, atmosphere, space), and various characteristics of its construction (e.g., unusual material, construction technique, etc.).

Re-roll on Table 1 if results from Table 2 can’t be reconciled, but first consider whether a bit of thought might not make non-obvious pairings work in a way that actually increases the sense of ‘we’re not in Kansas anymore’. For example, “individual dwellings” and “orbital structure – sphere” might give you the Solaria stage of Marshall T. Savage’s The Millennial Project (see plate 15 particularly for the glorious bubble habitats in a golden ring around the sun). Or, “world city” and “earthscraper” might suggest a vast number of pits that have multiplied and spread out until the planet’s surface has been covered with, perhaps circular, ‘bull’s eyes’ as seen from space.

Table 2: Type of Habitation
D66 Type Description and/or examples
11 Undersea Underwater structures e.g. Undersea Quest (and sequels) – Frederik Pohl & Jack Williamson or on a much smaller scale, The Watch Below – James White.
12 Sea surface Fixed dwellings or cities on the surface of oceans or seas e.g. the Aquarius stage of The Millennial Project – Marshall T. Savage.
13 Underground Habitation which is entirely underground e.g. The City of Ember – Jeanne DuPrau [and film, 2008].
14 Earthscraper This differs from an underground city by virtue of an open central space around which the structure is built. The central space will be sealed in some way with a translucent material or dome to allow light in. See the ‘depthscraper’ in Everyday Science and Mechanics, November 1931.
15 Cave adaptations Natural underground formations converted to human habitation e.g. ‘A Pail of Air’ – Fritz Leiber in Galaxy Magazine, December 1951.
16 Cliff/crater edge Homes or towns built around the edge of a crater or built into cliff faces e.g. Echus Overlook in Red Mars – Kim Stanley Robinson.
21 Tree/plant Biological structures, e.g. banyan tree of Hothouse – Brian Aldiss or perhaps the vast ‘caverns’ of Vigil Beta in Stellar Reaches, no.26, p.41.
22 Giant Fungus Some fungi may be large enough to create individual or even town sized dwellings or larger. They may be sealed artificially or using natural methods. Note that mycelium may also be used as a building material.
23 Burrow Creatures may leave burrows that are large enough to use as dwellings once sealed – perhaps artificially, perhaps with a natural product from the environment or the creature itself. Humans may be living in empty burrows, or in association with the still-present builders.
24 Shell The shells of large creatures, naturally formed or engineered to be shaped, sealed and used as habitation space.
25 Body The bodies of large creatures, prevented from decomposing, used as dwellings; on a large enough scale, possibly while the creature is still living.
26 Engineered biodwelling Habitations ‘grown’ from biotechnology, e.g. ‘Growing Skyscrapers’ – Adam Marek in Beta-Life – Martyn Amos & Ra Page (also an essay on the subject by Prof Susan Stepney immediately following the short story).
31 Sealed – horizontal axis Standard town or city on the surface of a world, sealed against the atmosphere, with air-lock access.
32 Sealed – vertical axis (arcology) Skyscrapers built around a vertical axis, e.g. the urbmons of The World Inside – Robert Silverberg, or the arcologies of Azun in Journal of the Travellers Aid Society (GDW), no.15.
33 Dome – bubble Classic golden age science fiction domed city e.g. Under the Dome – Stephen King.
34 Dome – multiple bubbles Two or more domes intersecting each other, e.g. Logan’s Run [film, 1976].
35 Faceted Dome Dome based on a geodesic polyhedron, e.g. Silent Running [film, 1972] is a good example although part of a spaceship rather than ground based.
36 Dome – forcefield/energy A non-physical dome – in standard Traveller terms this would be very high tech e.g. ‘The Box’ – James Blish in The Omnibus of Science Fiction (1980).
41 Mobile – track/rail A habitation mounted on a fixed track or rail along which it moves by some means e.g. Terminator on Mercury in The Memory of Whiteness & Blue Mars – Kim Stanley Robinson.
42 Mobile – tracked A mobile structure on tracks e.g. Traction Cities of Mortal Engines – Philip Reeve or, arguably, the Jawa sandcrawler of Star Wars [film, 1977].
43 Mobile – wheels A mobile structure on wheels e.g. Traction Cities of Mortal Engines – Philip Reeve [and film, 2018].
44 Mobile – walker A mobile structure using walker technology e.g. Ambulon in Dark Heresy [rpg].
45 Mobile – powered waterbourne A powered mobile structure on a sea or ocean surface e.g. Milliard City in Propeller Island – Jules Verne.
46 Mobile – sail/free floating waterbourne A free floating, or sailing structure on a sea or ocean surface e.g. the atolls of Waterworld [film, 1995].
51 Flying Aerodynamic wing lift technology.
52 Floating/flying – gas lift A floating or flying structure using lighter than air gas to keep it aloft e.g. Airhaven in Mortal Engines – Philip Reeve.
53 Floating/flying – antigravity A floating or flying structure using antigravity for lift or propulsion e.g. Floating Worlds – Cecelia Holland.
54 Floating/flying – exotic A floating or flying structure using a more exotic technology e.g. the magnetic levitation in Laputa in Gulliver’s Travels – Jonathan Swift, or spindizzy power in Cities in Flight – James Blish.
55 Upper atmosphere structure Dwelling or city located high in the atmosphere for density or mining reasons etc. May be on a pillar, or tethered, or use artificial gravity to remain in one place. e.g. Cloud City in The Empire Strikes Back [film, 1980 and other appearances].
56 Beanstalk Or space elevator, e.g. The Fountains of Paradise – Arthur C. Clarke (used more for transport however) or ‘The Rope is the World’ in Three Moments of An Explosion – Charles Stross (which has become a failing habitation).
61 Orbital structure – station Standard Traveller highport in orbit around a world; some Traveller editions have rules where these are automatic for certain starport types.
62 Orbital structure – pearls Often an intermediate stage on the way to a complete ring - multiple highports linked by cable or structure.
63 Orbital structure – ring An entire inhabitable artificial ring around a world; (around a sun it’s called a ringworld). e.g. Elysium in Elysium [film, 2013].
64 Orbital structure – sphere A bernal sphere built around a planet or free in space; (around a sun it is a dyson sphere).
65 Hollowed out asteroid An asteroid of ice or rock either entirely hollowed out or with warrens within e.g. a terrarium of 2312 – Kim Stanley Robinson.
66 Free floating/flying structures in space Technically starships or spaceships as they are likely to have some form of propulsion but may be vast enough or not moving towards an immediate destination to be more city like, e.g. generation ships or the starliners of WALL-E [film, 2008].

All DMs Optional
DM –1 on first die if TL12–
DM –2 on first die if TL10–
DM –3 on first die if TL8– (or consider the structures not built by inhabitants and can’t be maintained)

Note that it’s possible to have structures which are more than one category: a city, particularly, might count as underwater and sea surface, or a ‘horizontal axis’ township might be spreading up the sides of a mountain.

Referees might wish to consider – for ‘feel’ or ‘atmosphere’ or adventure purposes – the need in enclosed habitats to control any or all of power, utilities, atmosphere (gas mix, density, pollution), heat, humidity. Also note the stack effect may be an issue in earthscrapers or arcologies. The stack effect is the movement of air due to air buoyancy resulting from temperature and moisture differences. (An inversion layer, as often happens in the Los Angeles basin, is a natural example of the stack effect in action.)

In short, don’t just assume the characters’ next stopping place is a non-descript habitat similar to those they’ve seen a hundred times, but send them somewhere new and distinctive! Players will enjoy the change as well.

Adventure Seeds

  1. The PCs arrive at a starport on a small island where most of the habitation is under the sea. A cyclonic storm (hurricane or typhoon) is moving in and the local news reports suggest this storm is bigger than anything seen in living memory. A distress call is received from a nearby island. A family group need medical assistance for a seriously ill or injured child. Everything else is locked down and the PCs’ ship is the only one that can make it in time. The family live ‘under’ their island and the PCs, if they can get there, may shelter beneath the storm with the family. They won’t be paid for this mercy mission but news will leak out and they’ll get a favourable reception for trade deals.
  2. An ancient beanstalk is being used as accommodation for the poor and marginalized of a world. Systems are failing or repairs cobbled together from scrap; whole sections of the ’stalk are becoming lawless domains of criminal gangs. The PCs are asked to locate and rescue an aid mission that has gone missing.
  3. On an airless moon, a crater edge starport with terrific overlooks is the site of a ‘human flight’ competition which the PCs are invited to take part in. There are great cash prizes, not to mention high esteem for visitors who do well in various categories. Take it too seriously, however, and there may be a competitor who decides to sabotage the artificial wings that are used. (Or the PCs come across evidence of such sabotage amongst the serious players and will need to get close to the action to find out who’s responsible.)
  4. A local political faction concerned with ecological stability, environmental preservation, and sustainable use and replenishment of resources are the government of a garden world where they’ve either encouraged or forced the population to live in arcologies to protect the environment. (Or previous cultural tendencies have meant that that’s happened naturally with the faction being a natural(!) result of the political leanings of much of the population.) Careful, sustainable, husbandry of natural resources is permitted and nature tourism is allowed – but carefully managed. Indeed, there is a growing ‘naturist’ movement in certain areas and it is seen as very trendy amongst younger generations. The PCs are caught up in either a protest by groups trying to push the boundaries of what they’re allowed to do; or the government cracking down on resource use which is going “too far” and damaging, or likely to damage, the environment; or both simultaneously.

Author’s Note: My thanks to Jeff Zeitlin for some interesting and useful suggestions on a draft of this article as well as the inspiration for adventure seed #4.

Further Reading:

https://en.wikipedia.org/wiki/Space_colonization
https://phys.org/news/2016-02-colony-alien-world.html