A Residential Area
Emerging from the elevator your fellow passengers go their various ways as you enter a busy community without skyscrapers and freeways; a city which does not dwarf its inhabitants. The human scale of the architecture is emphasized by the long lines of sight, the frequent clusters of small fruit trees and parks, and the sense of openness produced by the broad expanse of yellow sunlight streaming down from far overhead. This is the central plain running the full circumference of the torus along the middle of the tube.
Houses are the most numerous structures. You are impressed by the architectural achievement in housing 10,000 people on 43 ha (106 acres) while maintaining a spacious environment. Spaciousness is achieved by terracing structures up the curved walls of the torus and also by placing much of the commerce (e.g., large shops, light industry, mechanical subsystems) in the volume of the torus which lies below the central plain on which most inhabitants live. Houses have plenty of window area to provide a sense of openness. Walls and doors are only needed for acoustical and visual privacy and not for protection from the weather.
Housing in the space colony (see fig. 5-4) is modular, permitting a variety of spaces and forms — clusters of one- or two-level homes, groups of structures as high as four and five stories, and terraced homes along the edges of the plain. Use of the modular components is illustrated in figures 5-5 to 5-7. (For more information see appendix B.)
As noted in chapters 2 and 3 the total projected area (defined in appendix B of ch. 3) required in the torus is 43 $m^2$/person for residential and community life, 4 $m^2$/person for mechanical and life support subsystems, and 20 $m^2$/person for agriculture and food processing.
Figure 5-8 (overleaf) illustrates these projected areas in terms of total surface area and the number of levels required for each function. By making use of multiple layers above and below the central plain, the apparent population density in the colony is reduced. Layers below the central plain are illuminated artificially. Figure 5-9, a longitudinal section of the toroid's tube, illustrates schematically the layers of the colony below the central plain. All the architecture within the enclosure of the torus must be distributed to satisfy several requirements: 1) the need for residences to be near the transportation spokes to the hub, 2) the need to balance masses around the rim of the torus, 3) the desirability of acoustically isolating residential areas from noisy commercial and service activities, 4) the need for fire prevention, and 5) the need to facilitate pedestrian traffic.
The total projected area within the torus is 678,000 $m^2$. If the height between decks is 15 m, the volume needed for agriculture and life support is $10 \times 10^6$ $m^3$. A volume of $8 \times 10^6$ $m^3$ needed for residential and community living brings the total volume ($18 \times 10^6$ $m^3$) to only 26 percent of the total of $69 \times 10^6$ $m^3$ which is enclosed by the torus. The "extra" 74 percent of the volume helps to reduce the apparent population density. The areas and volumes required and available are summarized in table 5-1.
TABLE 5-1 — FUNCTIONAL DISTRIBUTIONS OF AREAS AND VOLUMES IN THE STANFORD TORUS
| Use | Projected Area, $m^2$ | Number of Levels | Total Area, $m^2$ | Volume, $m^3$ | | :--- | :--- | :--- | :--- | :--- | | Residential | 430,000 | 3 | 1,290,000 | 8,000,000 | | Agriculture | 200,000 | 3 | 600,000 | 9,000,000 | | Life Support | 48,000 | 2 | 96,000 | 1,000,000 | | Total | 678,000 | — | 1,986,000 | 18,000,000 |
Consequently, the houses close to the elevator are already occupied. Since you are a latecomer and also only a temporary visitor, your apartment is some 400 m from where you enter into the torus. This is about the greatest distance anyone resides from an elevator, and the walk takes only 5 min. You might buy a bicycle if you were staying longer. Alternatively you can choose to walk 60 m to the ring road which passes around the torus at the edge of the plain and catch a transport car to the stop nearest your destination. Since you are a tourist and want to see what is going on, you decide to walk and start off down a tree-lined pedestrian way following the directions on the map you were given when you landed.
You are aware that the colony has filled up over the preceding 4 yr at the rate of about 2000 people per year. Equally as striking as the lack of traffic and wide roads is the presence of a flourishing vegetation. Stimulated by plentiful sunshine, brilliantly colored flowers bloom in profusion along winding walkways. You meet a colonist heading in the same direction as yourself. She tells you she is an engineer at the habitat controls center and is one of those responsible for the maintenance, modification, and control of the mechanical and electrical systems. A few questions about this gigantic and complex structure bring forth a flood of information from your companion.
To resist the atmospheric pressure and the centrifugal forces of its own mass as well as the internal masses, the shell has a skin thickness of 2.1 cm. The windows through which sunlight streams are some 65 m "above" you and are 2.8 cm thick.
Buried in the walls and under the decks of the torus are thousands of kilometers of wires and piping for electrical power distribution, water supply, waste disposal, and air dehumidifying.
Figure 5-6 — A possible apartment plan.
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Figure 5-7 — View of housing.
<!-- image -->Figure 5-8 — Allocation of space in the colony.
<!-- image -->The shell of the torus is designed to resist loads of 50 kPa of atmospheric pressure and the centrifugal forces of its own mass as well as 530,000 t of internal mass. Including the ribbed portion, the mass of the aluminum shell is 156,000 t. (Details of the design are presented in appendix A.) For the windows to resist the pressure of the atmosphere across a span of 0.5 m, the distance between ribs, the glass is 2.8 cm thick. This requires 48,000 t of glass.
The masses of the main components of the habitat (except for the extraction plant) are listed in table 5-2; the principal internal masses are summarized in table 5-3.
Figure 5-9 — Partial longitudinal section.
<!-- image -->TABLE 5-2 — SUMMARY OF HABITAT COMPONENT MASSES
| Component | Mass, t | | :--- | :--- | | Torus Shell (Aluminum) | 156,000 | | Windows (Glass) | 48,000 | | Spokes | 3,000 | | Hub | 1,000 | | Secondary Mirrors | 1,000 | | Main Mirror | 1,000 | | Radiator | 1,000 | | Solar Power Plant | 1,000 | | Total Habitat Structure | 212,000 | | Passive Shield | 9,900,000 | | Total Habitat Mass | 10,112,000 |
Arriving at your apartment house you bid the other colonist goodbye. The house is a combination of two duplexes and two studio apartments (see appendix B). Each of the studio apartments on the third floor has a small balcony on which some plants are growing. On a neighbor's balcony is an impressive stand of cherry tomatoes and lettuce in a few pots. Small patios below each balcony are surrounded by dwarf apple and peach trees.
Although small (49 $m^2$) your apartment is completely furnished in a compact, convenient and attractive way. Furniture and the few ornaments are made of aluminum and ceramics, a constant reminder that wood and plastics must come from Earth or be made from carbon, nitrogen and hydrogen brought from Earth. It takes a while to become accustomed to the almost complete absence of wood and plastics.
Although the apartment has a kitchenette, you decide it will be more convenient and pleasant to eat in one of the neighborhood community kitchens where you can meet and get to know neighbors as you dine with them. So you walk to the closest of these kitchens.
TABLE 5-3 — SUMMARY OF INTERNAL MASSES
| Item | Mass, t | | :--- | :--- | | Soil | 443,000 | | Water | 50,000 | | Vegetation | 1,000 | | Structures | 30,000 | | Atmosphere | 6,000 | | Total Internal Mass | 530,000 |
A glance around the dining area reveals young adults and a few children. Briefings before you left Earth had informed you that the community of the space habitat consists of men and women between the ages of 18 and 40, a few hundred children who came with their parents from Earth, and about a hundred children who were born in the colony. The population mix is that of a typical terrestrial frontier — it is hardworking, concentrating intently on the manufacture of satellite solar power stations and the construction of the next colony, a replica of this one.
As you sit down to eat, one of the few colony elders tells you of the philosophy behind the productivity and growth in the colony.
Despite the narrow focus of activities in the colony, he explains, there is considerable stimulation and innovation by the new settlers. The rapid growth of the settlement sustains a sense of dynamic change; but he warns that the stabilization of the community upon reaching its full size may result in the dissipation of that sense (ref. 1). A community as small and as isolated as the colony may stagnate and decline in productivity and attractiveness. The answer to the problem is continued growth by the addition of more colonies. Growth is important economically as well as psychologically, because as time passes the population will become more like that of Earth in its age distribution, with the productive fraction of the population diminishing from about 70 percent to between 30 percent and 40 percent. If more colonies are not established, the amount of production will decrease with time. He points out that only if the total number of people grows rapidly can production in space be maintained at its initial level and be increased sufficiently to meet growing demands of Earth's markets for satellite solar power stations. Furthermore, he explains, the aggregation of habitats into larger communities will enable the colonies to develop cultural and technological diversity similar to that which permits the larger cities of Earth to be centers of innovation and disseminators of cultural and technological change.
The colony experiences the egalitarianism of a frontier reinforced by the esprit of a group of people working together with a sense of mission on a common task. His face glowed with enthusiasm as he declared that this spirit, more than heroic adventures or romanticized challenge, is what makes the colony a rewarding place to live. Egalitarianism is tempered by certain realities within the colony. The entire colony has a sense of elitism simply because each individual colonist was selected as a settler. A distinction developing between those with clean and "shirtsleeve" jobs and those who work in hazardous, heavy industry, or zero atmosphere jobs, has only small effects and will not produce marked socio-economic differentiation for a number of years.
He excuses himself, saying he has a meeting of the "elders" to attend.
You continue eating alone. Your meal is satisfying — chicken, peas, and rice followed by apple pie for dessert — hardly the fare which science fiction writers led you to expect. There are no dehydrated "miracle" foods or algae cake because the colony is equipped with extraordinarily productive farms that raise food familiar to people on Earth. Your interest is aroused and you decide to tour the agricultural area next to see how this food variety is achieved.
Figure 5-10 — Section showing distribution of residential and agricultural areas.
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An Agricultural Area
To promote diversity and to build in redundancy for safety's sake the torus is divided into three residential areas separated by three agricultural areas. The latter is segmented into controlled zones which may be completely closed off from other zones. This arrangement permits farmers to use higher than normal temperatures, carbon dioxide levels, humidity and illumination in the controlled zones to force rapid growth (fig. 5-10). Partitioning also inhibits the spread of any disease of plants or animals from one zone to another.