Training Materials and Teacher Tools

The information at the links below is provided to assist participants in doing calculations and understanding basic concepts that are integral to completing a proposal for entry in our global event. 

Note to Teachers and Advisors: Above all, SSDCs are designed as innovative learning experiences that will help you inspire students. Although we feel that students derive the most benefit from going through the entire Competition process, educators are welcome and encouraged to use the materials as tools for other classroom and extracurricular activities.

Updates in progress

Space Settlements, or Space Colonies, first received serious attention in the mid-1970’s, with interest primarily fueled by two NASA-sponsored studies led by Dr. Gerard O’Neill and conducted at Stanford University during the Summers of 1975 and 1976. Participants in these studies published books and articles that first appeared in the aerospace technical community, and eventually were popularized through book clubs and general-circulation magazines. Science fiction authors wrote stories and novels about characters living on space settlements. Technical societies sponsored conferences where details of construction and operations were presented. Architects designed prototype communities as a model for how humans would live in space. College degrees were earned with Masters theses about space settlement design. At the peak of their popular attention, the counterculture Whole Earth Catalog enthused about the concept of space colonies, and Dr. Timothy Leary (yup, the LSD guy) did lecture tours, and interview shows on TV and radio, about how wonderful life would be in space.

From their beginnings, the most contentious issue concerning settlements-in-space was the huge development, maintenance, and logistics cost, primarily due to the expense of launching thousands of tons of goods and materials into orbit. In order to make the concept work, a compelling economic necessity had to be found, and conveniently presented itself in the energy crisis and oil embargo of the early 1970’s. Solar Power Satellites became an almost obvious solution to the energy crisis: build a structure in space up to three miles wide and 20 miles long, cover the structure with solar panels, and generate ten gigawatts of electricity. Such large structures would, however, require humans to build them and human attention for maintenance. There would be demand for lots of Solar Power Satellites, so we would need places for their builders to live in space, and space settlements would provide an environment in which they could feel right at home. This whole scenario may have been a bit naive, but the studies were done, dreams were kindled, and a lot of people decided they would be ready to pack their belongings and go live on the new frontier in space just as soon as the first space settlement was ready to go. An organization called the L5 Society was founded, proclaiming in its By-laws that its last meeting would be held on the first space colony, its purpose for existing then having been fulfilled (the L5 Society merged with the National Space Society, and consequently that By-laws provision no longer exists).

Although numerous concepts were sketched for space settlements, the research of the 1970’s produced three primary designs, each solving the design challenge with a somewhat different approach. Figure 1a shows an exterior view of a Stanford Torus, the design that the NASA-sponsored studies developed to an impressive level of detail. The torus is one mile in diameter, and rotates at one rpm in order to produce one g of acceleration to simulate gravity. The cross-section of the torus interior is about 420 feet, and it could accommodate a population of 10,000 living inside, with all agricultural crops and services required to sustain them. Other major features are a large mirror “floating” above the settlement, reflecting sunlight to solar panels that generate power and smaller mirrors around the hub that then direct daylight into the living areas of the torus; and a facility for refining lunar ores to be used in Solar Power Satellite construction, which is isolated from the habitable areas by a six-mile-long transportation tube. Figure 1b represents a residential area of the Stanford torus, and shows that the designers envisioned an environment with open space, greenery, and low-rise housing. Some artists’ Stanford Torus interior views showed brooks and jogging trails.

The Bernal Sphere, shown in Figure 2a, was a spherical approach to the design problem. This design was also intended for a population of 10,000, who would live in the spherical volume in the middle. Sunlight is directed into the interior of the sphere by mirrors at either “end” of the spherical section. The banded toruses, extending from either side of the habitation sphere, house the agricultural areas. This shape made construction easier, and could afford the possibility of maintaining different climates or seasons in different toruses in order to grow a variety of crops. Figure 2b shows an interior view of a Bernal Sphere, again illustrating the designers’ priority for providing green areas and the appearance of low-density housing.

The most ambitious of the space settlement designs was Island Three, shown in Figure 3a. The twin counter-rotating cylinders are four miles in diameter and twenty miles long, claimed to be large enough to accommodate a population of up to ten million people. The cylinders are made up of three land areas about two miles wide, alternated with three window areas of the same width; mirrors angled from one end of each cylinder reflect sunlight into the windows. The small pods ringed around the other end of each cylinder provide agricultural and manufacturing areas. The interior view shown in Figure 3b depicts almost a rural population density; written descriptions noted village-like population centers dotted over hundreds of square miles of terrain.

A general consensus of space settlement designers was that a logical place for these structures is at one of the Earth-Moon libration points. There are five Lagrange libration points in a system where a large body is in orbit around a much larger body (e.g., the Moon in orbit around the Earth); these are places where the gravitational forces due to both objects “balance out” in a way that enables a settlement to stay in one spot relative to both objects. Figure 4 shows these places, called “Libration Points”. “L4” and “L5” are the most stable of the five; they are on the same orbital path as the Moon, one-sixth of the way around in either direction from where the Moon is (equivalent to the locations where the Trojan asteroids have collected in the Jupiter-Sun system). Because of the perturbations of other objects in the solar system, these are not discreet spots; objects placed in these areas will go into large orbits around the actual points. Indeed, a large number of space facilities could be placed “at” L4 and L5. The other three libration points act somewhat like “saddles”–if an object is perturbed and drifts a small distance, it will tend to continue drifting away until it assumes a more normal orbital path. Objects could, however, be kept in these locations if their engines are used to continually nudge them back where they belong.

Some of the best data developed during the NASA space settlement studies resulted from analyses of human needs. Excerpts from some of the Tables that presented these data are included.

In the late 1970’s, NASA funding for space settlement research was discontinued, and gradually the enthusiasm waned. Most people forgot about the energy crisis, and for a time the priority of space enthusiasts was to save any manned space program at all. Only a few individuals expressed the conviction that it was still inevitable people would eventually live in space on a large scale, although they knew that the hoped-for timetables (“L5 in ’95!”) would not be met.

In the past few years, however, more brave souls have been revisiting the idea of large-scale habitats in space, and some venturesome individuals are again publicizing the idea that Solar Power Satellites are a reasonable alternative to conventional power plants. The key to a revival of serious consideration of space settlements is transportation costs. Government and industry are beginning to demonstrate a commitment to develop launch vehicles that could lift payload into orbit for as little as $500 per pound. That is still a huge expense, but makes some commercial ventures feasible that could not possibly generate a profit with today’s launch costs of $2,500 to $10,000 per pound. There also is also finally a funded program for returning missions to the Moon; establishment of a lunar base could lead to mining operations that would provide a relatively inexpensive source of materials for space settlement construction.

Table 1. Summary of Community Space and Area Allocations (from 1975 NASA Summer Study)
Space Use
Surface Area
Estimated Ht.
Public and semipublic
    Assembly (church/halls)1.510
    Rec. and entertain13
Public open space1050
Service industry46
Misc. infrastructure7.14
    Plant growing areas4415
    Animal areas515
    Food processing, collection, storage, etc.415
    Agriculture drying area815

Table 2. Average Daily Space Settlement Diet (g / person) (from 1975 NASA Summer Study)
Source Amount
Source Cal’s
Dry Plant ProduceWheat180608130.13.624.3
and Fruit
TOTALS 18142445417.149.7100.2
Note: current understanding of human nutrition and health may change the recommended diet

Figure 3. Animal Food Requirements (from 1975 NASA Summer Study)

Beef steer:  1 steer for 11 persons
    Harvested at 400 kg after 16 months
    Metabolic requirements for 1 / 11  250 kg steer
        300 g sorghum mix/day
        200 g soybean mix/day

Roasting Chicken:  5.6 chickens / person
    Harvested at 2.6 kg after 25 weeks
    Metabolic requirements for 5.6 kg at 1.1 kg each
        37 g fish meal/day
        150 g soybeans/day

    Harvested at 3.4 kg after 125 days
    Metabolic requirements for 2.8 rabbits at 1.8 kg each
        100 g sorghum/day
        100 g soybeans/day
        20 g corn/day

Dairy Cattle
    400 g cow produces 12.45 kg milk/day
    Metabolic requirements for 1 / 16.6 cow at 400 kg
        350 g sorghum mix/day
        100 g soybean mix/day

Laying Hens
    1.5 kg hen lays 5 eggs/week, 54 g/egg
    Metabolic requirements for 6/10 hen at 1.5 kg
        20 g soybeans/day
        30 g corn/day

    Harvested at 2 kg in 1 year
    Metabolic requirements for 26 fish at 1 kg each
        100 g soybeans/day
        81 g animal meal/day

Figure 4. Crop Yields (from 1975 NASA Summer Study)

Anticipated Settlement Yields
Crop     g/m2 / season     season  g / m2 / day
Wheat        2800           90        31

Rice         3192           90        35

Soybeans     1800           90        20

Corn         5300           90        58

Sorghum      7560           90        83

& Lettuce    9240           70       132

Space Characteristics and Resources

Space is not a friendly place. Mostly, it is nothing: vacuum, and apparent lack of gravity. What little there is in space is mostly hazardous, even the things that are assets.

One asset abundant in space, at least out to Mars orbit, is power, in the form of energy from the Sun that can be converted into electricity. The supply of power from the Sun is continuous and uninterruptible, and it is 6 to 15 times as intense in Earth orbit as on the Earth’s surface (solar energy intensity is absorbed by Earth’s atmosphere). Solar energy does, however, present hazards, in that it is harmful to humans who are not shielded from it. The sun is also the source of flares producing intense radiation deadly to unprotected humans and equipment.

The Sun is not the only source of hazardous radiation in space: cosmic rays, gamma rays, and X-rays are also part of the ambient space environment, at sufficient intensities to be damaging to humans. Earth’s magnetic field prevents most of this radiation from reaching low earth orbits and the planet’s surface; it also, however, traps dangerous levels of protons and electrons in the Van Allen radiation belts, which begin at 250 to 750 miles altitude, and extend to between 37,000 and 52,000 miles altitude.

The primary law of space is Orbital Mechanics, which determines where things can stay and where they can go. Everything in space is moving, attracted by gravitational fields (usually interacting) of every major object in the vicinity. Which orbit an object is in depends on its position and velocity at any particular time. Orbits are changed with acceleration due to thrust, usually from rockets.

Satellites are constrained to be far enough above most of any atmosphere that an orbit can be sustained for a few days before decaying through friction with the atmosphere (about 100 miles above Earth’s surface; a 150-mile Earth orbit can be maintained for about five years, a 250-mile orbit for about ten, with variations depending on solar activity and other factors that can cause the atmosphere to expand or contract).

Objects with bigger cross-sections experience faster orbital decay. Higher velocities put objects in higher orbits; an object achieving “escape velocity” (25,000 mph for Earth) will leave the influence of its “host”, and go into orbit around something else. Orbits are also not perfectly stable, requiring that satellites use small rockets for “station-keeping” to stay where desired. Some quirks of orbital mechanics cause gravitational forces due to two large bodies (e.g., moon and Earth, or Earth and Sun) to balance in some locations, creating “Libration Points” that are either unusually stable (L4 and L5) or are unstable but provide opportunities for maintaining spacecraft in otherwise impossible locations (L1, L2, and L3). All five libration points can host multiple small objects in local orbits: around stable L4 and L5, these orbits are large and apparently elliptical; around unstable L1, L2, and L3, orbits are convoluted but viable with station-keeping propulsion.

Solid objects in space are also both hazards and assets. Debris is a nuisance: at orbital velocities, even paint flecks can do damage, and small bolts or rocks can puncture spacecraft cabins. Most human-caused debris is in Low Earth Orbit (LEO), Geosynchronous Earth Orbit (GEO), and Molniya orbits used for Russian communications satellites; all objects larger than three inches in diameter are tracked by the United States Air Force, and warnings are provided when collisions are predicted.

Natural debris is primarily dust, which can degrade materials that stay in orbit for long periods of time. The Moon and near-Earth asteroids, however, represent vast reserves of relatively easily accessible resources; getting to them requires much less energy than launching materials from the Earth. The lunar surface is 99% oxides, of silicon, iron, aluminum, calcium, magnesium, and titanium. Asteroids are of several types, and can contain nickel, iron, water, carbon, and carbon compounds.

The space environment near Mars is even less hospitable than near Earth. With no magnetic field, Mars lacks the equivalent of Van Allen radiation belts that provide some protection for human operations in GEO. Solar radiation in Mars orbit is only 36% of the intensity near Earth, requiring larger solar panels to produce the same amount of electricity. Moons Phobos and Deimos are close to the planet; at 5825 miles altitude, Phobos is below Mars synchronous orbit. Neither of the two tiny moons has enough gravity to produce a Martian equivalent of libration points.


A common difficulty for Space Settlement Design Competition teams is the business of figuring out the types of space vehicles that are needed to support construction and operations of a space settlement.

In order to get your group thinking about this topic, first think about where they want to go, and the different kinds of vehicles that would be required to get to each place. The Space Settlement Design Competition description of the company Northdonning Heedwell gives some clues. First, we can tell from that description that in the foreseeable future, nobody will develop the Millenium Falcon, the starship Enterprise, the shuttle Galileo, or any ability to teleport or “beam up”. We will have to use more conventional methods.

The primary factor in determining the efficiency of an aerospace vehicle is weight. The more an aircraft or spacecraft weighs, the less paying cargo it can carry with the same engine power, or the less distance it can go with the same amount of fuel. When carried to the extreme, an aircraft could be so heavy that it would not be able to get off the ground. The Space Shuttle typically carries up as much as 50,000 pounds to a 150 mile orbit. If it needs to go farther, perhaps to 350 miles, it can only complete the mission with 20,000 pounds or less. If it were flown with no cargo at all, it would not be able to get more than 600 miles above the Earth. Because so much energy is needed to get off of the Earth’s surface, most of the Space Shuttle’s weight on the launch pad is fuel. On the other hand, satellites or other vehicles that are already in orbit can move to different orbits with relatively little fuel.

We can anticipate that three basic types of transportation vehicles will need to be considered in Space Settlement Design Competition proposals. Although there can be different vehicle designs in each of these major vehicle categories (to account for passenger vs. cargo operations, or different kinds of cargo), the judges will be looking for teams’ appreciation of limits imposed by foreseeable technology on vehicle operations:

Launch Vehicles

The space vehicles we are familiar with in real life are launch vehicles. Their job is to get cargo (satellites, experiments, crew, and Space Station supplies) off the Earth’s surface, through the atmosphere, and into orbit. Their principal features are huge fuel tanks, engines, and shapes with insulation that enable them to survive a high-speed boost through air. The Space Shuttle Orbiter weighed about 200,000 pounds (empty) at landing, and carried about 50,000 pounds of cargo. As a Space Shuttle stood on its pad just before launch, it weighed 4.5 million pounds–almost 95% of which was fuel, the weight of the tanks that contain the fuel, and the engines that burn the fuel. All launch vehicles have smooth aerodynamic shapes to reduce drag through the atmosphere, and large reusable vehicles like the Space Shuttle need wings, tail(s), landing gear, and thermal protection systems for the mission home; after these vehicles reach 150 miles of altitude, all of this stuff is useless weight, which requires additional fuel to push it around to wherever the vehicle needs to go.

Studies are being conducted on space elevators to do the job now accomplished by launch vehicles. The concept starts construction by deploying counter-balancing ribbons from a terminus in geosynchronous orbit, one down to Earth’s surface and the other an equal distance up. A vehicle would climb or descend on the ribbon between the surface and space. The Competition Co-Founders are watching this research; although the physical principles appear sound, no material currently exists that can be manufactured into a cable or ribbon strong enough to withstand the forces induced by this application. On-orbit experience with space tethers also shows that unexpected effects may delay development of this technology. Design Competition proposals that include space elevators will be penalized.

On-Orbit Vehicles

Unless a space settlement is located at about 250 miles of altitude or less, it is not practical to consider routine operations of launch vehicles directly to the settlement. Special on-orbit or orbit transfer vehicles will not need huge fuel tanks, wings, tail(s), thermal protection systems, and most of the other physical features (weight) that distinguish launch vehicles. Most on-orbit vehicles will fire their engines for only a few minutes at a time, and coast through the vacuum of space to their next destination. Indeed, even the engines are smaller; the engines the Space Shuttle uses for its on-orbit maneuvers generate only 6000 pounds of thrust. These vehicles also can be boxy or oddly shaped, since streamlining provides no advantage in the vacuum where they live. Of course, for cargo and passengers to get from the Earth’s surface to a space settlement’s location, they will need to transfer from a launch vehicle to an on-orbit vehicle, and it can be expected that some sort of Space Station or on-orbit Port facility would provide services to support this operation.

Space vehicles that need to go to destinations outside of Earth orbit, however, will have somewhat different design requirements. The huge distances involved in getting to other destinations in the solar system make it necessary to carry larger fuel tanks than would be needed by Earth-orbit vehicles. Exotic propulsion systems also become interesting, including ion engines (very low thrust engines that operate continuously for long periods of time), solar sails, or perhaps nuclear engines.

Landers and Atmospheric Vehicles

Because of huge launch costs for getting materials from Earth, it is expected that some (perhaps most) materials employed in space settlement construction will be acquired from extraterrestrial sources. The Moon is an obvious materials source, and some asteroids with orbits that bring them close to Earth could prove very useful. Every destination will present its own priorities for vehicle design. Lunar landers will need landing gear and engines for landing and ascent. Asteroid mining vehicles will need some means for staying attached to their targets, and for harvesting, processing, and transporting large quantities of ore. For Space Settlement Design Competition scenarios that involve settlements on or near other planets (e.g., Mars), atmospheric and environmental characteristics must be considered in designs of the vehicles that service these communities.

Practitioners of engineering design learn early in their careers that successful designs respond to requirements. Although the Space Settlement Design Competition Request for Proposal (RFP) lists the customer’s basic requirements for your team’s space settlement design, there are a lot of implied requirements in the requests for a "pleasant living and working environment" and "a comfortable modern community environment". Your team needs to think about what the judges will be expecting–think of your space settlement as a place where people will raise their families and build their careers, and think of the judges as the people who need to be convinced that they will want to live there. The better your team’s design proposal shows a space settlement that will be a pleasant place to live, the more likely your team is to win an invitation to the Finalist Competition. Participants will also come up with better designs if they develop an appreciation for why the RFP includes what it does.

The design requirements for space settlements derive from the simple question "what do people need that doesn’t exist in space?"; the simple answer to this question is "just about everything".

During the Finalist Competition, we use a tool to help participants appreciate just how much "everything" really is. The "BRAINSTORMING" SESSION is a process that gets a group of people with knowledge about the problem into a room, sets their minds free to release any thought that occurs to them, and captures those thoughts for further analysis. Typically, brainstorming sessions are used in industry to solve problems. For Space Settlement Design Competitions, this is a very useful technique for helping participants identify the problems that their designs must solve.


For Brainstorming to work, very rigid rules must be established. There are three distinct parts to the process:

  • Free-wheeling non-critical idea-generating session
  • Review ideas–toss unworkable, frivolous, and redundant ideas; group similar ideas
  • Document the ideas generated–make sure all participants get a copy of the idea list

This process may be iterated by doing further sessions to develop detailed ideas that will make a concept feasible.

Brainstorming has gone out of favor in industry, mostly because people usually only do the first step, and not the critical follow-up exercises. The first step is what’s fun, but the ideas are only cemented and made useful through analysis and documentation.

The idea-generating session itself can have some pitfalls, too. If the following rules are followed, however, there is no better tool for rapidly developing a wide-ranging collection of creative ideas:

  • The statement of the problem to be addressed is agreed to with all participants
  • Participants say every idea that they think of
  • Every idea is written by the facilitator or an assistant, so that all participants can see (on large sheets of paper, overhead projector transparencies, or a projected computer image)
  • No idea is criticized during the session
  • The facilitator(s) and scribe(s) only add ideas generated by the participants

It is essential that every idea be written, no matter how dumb, and that no idea be criticized during the idea-generating session. Dumb ideas that occur to creative people act like dams; until the dumb idea is released, it will stop the flow of more creative ideas. By not allowing criticism, there is no stigma attached to announcing a dumb idea, and it can be removed during the second step of the process. Oddly, release and documentation of a dumb idea will frequently ignite a creative spark in another participant, and may lead to the idea that provides the best solution to the problem. These sessions can get pretty frisky, and it is generally accepted that an optimum size for a Brainstorming group is between 10 and 15 (you want everybody to contribute ideas; with a smaller group, nobody has an excuse for not speaking up). If there is extra room, split the participants into two groups, have them run separate Brainstorming sessions, and compare the results.

Problem Statement

For Space Settlement Design Competitions, we generally conduct Brainstorming sessions with the following problem statement:

What does a community of humans need to stay alive, healthy, and happy in space?

We are constrained for time during Space Settlement Design Competitions, and will usually only run the idea-generating session for 10 to 20 minutes. During that time, it is not unusual for the scribe(s) to get a list of ideas six or seven hand-written transparency pages long. Sessions based on this problem statement can easily last for 30 to 45 minutes (sessions in industry often run for one and a half to two hours). The facilitator can keep the session going by asking questions that will direct thinking processes out of a rut, perhaps coming back to a thought pattern that didn’t appear to have played itself out, or steering thinking along a different track. If participants have been concentrating on the "healthy" part of the question, the facilitator may suggest that the question also includes "happy". The facilitator may remind participants that the question includes the word "community". Sometimes, just the reminder that you want participants to "speak up!" or "tell me ANYTHING that comes into your head!" will get the ideas flowing again.

When you analyze the list your team ends up with, you will find what we have found in dozens of experiences with Brainstorming on this problem statement: the first few minutes will concentrate on "technical" needs, but the majority of the ideas would apply to any community of humans anywhere. The Brainstorming session ends up being a terrific tool for reminding participants that people have the same needs no matter where they live, and we must make sure that our personal needs are met by the technical design. Incidentally, no significance should be attached during analysis of your list to specifics of the order in which the ideas were written.

When you finish categorizing, fleshing out, and documenting the ideas that come from your Brainstorming session, you will have a set of requirements from which to start developing design details, especially those regarding interior design and general habitability. The customers’ RFP defines minimum requirements for the project; winning teams both meet the requirements and develop a design in which the customer would like to live.

Perhaps the most challenging parts of the Space Settlement Design Competition proposal to develop are the schedule and cost estimate for settlement completion. This is not by accident–schedule and cost estimates are also the most challenging part of “real life” proposals in industry.

The Space Settlement Design Competition judges are engineers and managers in industry, and are familiar with the challenges of schedule and cost estimating. They will not base their selections of Finalist Competition invitees on the shortest schedule or the lowest cost. What they will be looking for is that the teams have gone through the thinking processes that would lead to reasonable numbers.

Schedules are based on insight into how engineering companies complete projects. The figure summarizes the process by which product ideas are turned into designs and ultimately become real things. Notice that at nearly any point in the process, something can go wrong that sends the whole process backwards for more design work. Extra time always needs to be allowed in the schedule to absorb these when they happen.


How long it takes to go through the process depends on the size and complexity of the project. For a new kind of mousetrap, it may take only weeks to develop a prototype, test it, and go into production; selling the idea to wholesalers, however, may take years. For the Space Shuttle, research into design concepts started in 1969 and the first flight was in 1981, without having to accomplish the last few parts of the standard process. Space Settlement Design Competition judges do not expect every team to come up with a perfect and thoroughly realistic schedule for their designs. It is expected, however, that they allow schedule time for detailed design, analysis, and testing before they show any manufacturing activities. The schedule needs to show time for transportation of materials and population to the settlement. The teams also need to consider that it takes a finite amount of time after the structure is completed to finish off the interior, establish farms, and move the residents into their new homes.


Estimation of costs is the most frustrating challenge for Space Settlement Design Finalist Competition participants, especially since it is the last thing they do, it’s getting late at night, and they are exhausted when they try to do it. They start out by thinking they don’t have a clue about how to figure out what the project might cost. When they come looking for help, we show them that they already have some pretty good ideas about how much things cost–they know about how much a car weighs, and about how much it costs; the cost per pound is a good rough estimate for costs of ground vehicles and robots. We tell them that the cost of a year’s work from a typical technical employee (including overhead and benefits) is about $150,000 per year; we also caution them that if they think they can spend trillions of dollars a year, there are not enough available workers in the economy to spend that much money. We also point out that the primary cost driver for building anything in space is transportation; even at a bargain-basement cost of $500 per pound launch costs from Earth, very few things would cost as much to acquire as they cost to launch.

Acquire additional insight into realistic schedule and cost estimating by observing construction projects in communities and by researching news reports about major construction projects worldwide. Reports of aircraft orders will provide costs and delivery schedules. Business journals report numbers of employees in major companies. News media report on costs and construction times of airports, skyscrapers, sports arenas, and government buildings. Source data are all around us–we only need to realize that they are useful to us.

Although teams need not compute orbits for Space Settlement Design Competitions, it is important to recognize orbital mechanics as a restriction on where things can go and stay in space. Some calculations can illustrate this.

Orbits are ellipses, and the body being orbited (the Moon and most satellites orbit the Earth; planets and interplanetary satellites orbit the Sun) is at one of the foci. For the purposes of Space Settlement Design Competitions, it is sufficient to generalize by considering only circular orbits:image missing

Use this equation to figure out how fast the Space Shuttle goes, or how fast the Earth moves around the Sun. An exercise is included here that demonstrates use of this equation for figuring out altitudes of geosynchronous satellites.

An interesting feature of orbits is that the faster a satellite is moving, the higher the altitude of its orbit. Because the distance required to travel completely around the orbit grows directly as a function of altitude (perimeter of a circle is pi x d), it takes longer to complete a higher orbit than a lower one. This produces an odd phenomenon: if the Space Shuttle follows the International Space Station in the same orbit, the Space Shuttle must slow down and drop to a lower orbit in order to catch up for a rendezvous with Space Station. Use the orbit equation to figure out the relationship between orbital altitude and the time required to complete an orbit. image missing

Orbital mechanics also determines how long it takes to get from one place to another. The most efficient way to get from one orbit (place) to another in space is to perform a “Hohmann Transfer”; this is an elliptical orbit that has one end of the ellipse on the orbit that is being left, and the other end of the ellipse on the destination orbit, as shown in the figure. The people who calculate orbits for a living are most interested in the amounts of energy that will cause the satellite to leave its original orbit on the proper trajectory, and will cause it to stay in the new orbit. For Space Settlement Design Competitions, we are most interested in the amount of time required to get from one place (orbit) in space to another.

The time of flight for a Hohmann Transfer between two orbits is defined by the following equation:
image missing

An exercise is included that shows how to use this equation to calculate the time required to get to Mars. If we were to do this calculation for other orbits, it would yield the following travel times between possible destinations in the solar system:

Consider this table of transfer times from earth:

the Moon 5 days
Venus 146 days
Mars 259 days
the Asteroids 1.23 years (average)
Jupiter 2.74 years
Saturn 6.04 years

These mission durations can be reduced if more energy (fuel) is expended to accomplish the orbital change. Expending less energy will simply not get the satellite to the intended location, so these represent maximum durations of direct missions to these destinations.

Getting to these destinations is complicated by the fact that there are only certain times when you can go–you must select your departure time so that you and the planet arrive at the same spot on the planet’s orbit simultaneously–if you choose another time, you will get to the planet’s orbit, but it won’t be there. For the Moon, this is merely a matter of selecting the appropriate time of day. For the planets, however, mission planners may have to wait years for Hohmann Transfer opportunities. For Space Settlement Design Competitions, we do not expect teams to select actual mission dates; we do, however, expect them to consider travel time to space settlement locations in their schedules.

Where do communications Satellites Orbit?

Communication satellites are in geosynchronous orbit, which means that they orbit around the Earth at the same rate the Earth spins on its axis. They therefore appear to remain in the same spot over the Earth.
image missing

This is the ONLY conventional circular orbit that is geosynchronous. Think about what a satellite’s orbit would look like from a point on Earth if it were at this altitude, but inclined with respect to the Equator. Remember, the orbit must be around the center of the Earth. (It is not possible for a conventional spacecraft to stay above a single spot that is not on the Equator. A design suggested by Dr. Robert Forward would, however, enable a spacecraft to remain at a stationary location above a different latitude through use of a solar sail; this “stacked orbit” technique has not been implemented.)

How Long Does It Take to Get to Mars?

The time of flight for a Hohmann Transfer between two orbits is defined by the following equation:
image missing

The International Space Settlement Design Competition judges expect that your team of students will design a Space Settlement that provides artificial gravity for its occupants. Although there are some schools of thought advocating zero-gravity habitation in space, the Foundation Society considers this a strong “quality of life” issue; any proposal for a space settlement design that does not provide artificial gravity will need a very compelling argument in order to win favor with the judges.

The judges will, however, favorably consider proposals that advocate other than one Earth gravity. Proposals should justify their selection of artificial gravity acceleration; the judges are mostly concerned that the students have considered implications of their decision (e.g., less acceleration enables structural integrity with less weight; more acceleration could enhance health and fitness of the occupants).

The judges only know of one way to produce artificial gravity with technology that will be available within the foreseeable future: the settlement must rotate. If students come up with any other scheme for providing gravity, they must provide compelling justification. The judges are also familiar with studies that predict occupants will become ill if subjected to rotation rates greater than three revolutions per minute; they will look most kindly on rotation rates of one revolution per minute or less.

The judges also expect that a settlement which provides artificial gravity through rotation will have circular cross-sections in those volumes that are rotating. The figure (from a mid-1970’s NASA study) shows suggested configurations for rotating space settlements. Your team may choose one of these or a hybrid of several. Non-circular designs would need very strong justification.

The amount of “gravity” induced by spinning can be calculated, and it is expected that Space Settlement Design Competition proposals will specify both rotation rate and the magnitude of artificial gravity produced. An exercise is included that demonstrates this calculation.

EXERCISE: Artificial Gravity How fast does a Stanford Torus spin to have acceleration equivalent to one Earth gravity?
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Suggested Shapes for Rotating Space Settlements
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Despite improvements in physicists’ ability to understand and measure forces due to gravity, rotation remains the only known reasonable means to provide artificial gravity (or pseudogravity) for settlements in space. Living in a rotating environment can, however, be disorienting.

Simply stated, for a rotating volume to be comfortable for normal people and to provide a practical amount of “gravity”, it must be big. Although it is generally accepted than many humans can tolerate a rotation rate of three revolutions per minute (rpm) for long periods of time, it is also recognized that quality of life for a wide range of human ages, activities, and fitness requires a rotation rate of one rpm or less. This means that a community providing the equivalent of one Earth gravity must be at least one mile in diameter.

The issue is that rotation produces not only the outward or centrifugal acceleration simulating gravity inside a rotating structure, but it also induces an effect called the “Coriolis force”. Coriolis is not a real force; it is not detectable by a person who stays still in a rotating environment. It does, however, feel very real to a person who is moving or watching something move in a rotating environment. It is due to the fact that we expect things to move in straight lines, according to the laws of Physics, but our senses don’t recognize that the “ground” in a rotating settlement is moving in a curve.

In order to visualize the Coriolis effect, imagine a hamster wheel with an inside surface “paved” with paper. Imagine that you draw a straight chalk line on the paper in the rotating wheel, by moving the chalk toward you from the far rim to the near rim. When you take the paper out of the wheel, you will notice that your line is curved. In a rotating space settlement, a ball thrown from one rim toward the other will appear to follow that same type of curved path.

The amount of Coriolis force that is felt or sensed depends on the speed of rotation. The Earth itself is a rotating environment, too, but at a rotation rate of one revolution per day, the Coriolis force is imperceptible. We do, however, know it is there, because it affects the weather and the direction that water swirls as it goes down a drain. In a one-mile diameter settlement rotating to produce the equivalent of one Earth gravity, however, the effect is very noticeable. When an object is dropped, where it hits the “ground” is about 10% off to the side from where we expect it to land. A three-point basketball toss is offset by several inches. A long football pass is offset by a few feet.

To make the situation worse, the direction of the offset appears different, depending on the direction in which the ball is thrown. Imagine again the curved line on the paper in the hamster wheel – if the line were drawn from the other side of the rotating wheel, it would curve in the opposite direction. A spider sitting on the paper in the rotating wheel would see one line curving from left to right, and the other line curving from right to left. Motion parallel to the direction of rotation produces another Coriolis effect: if you run in the direction of the rotation you will feel heavier, and a ball thrown in that direction will go straight but will appear to fall faster than it should. If you run opposite to the direction of rotation, you will feel lighter, and a ball thrown in that direction will also go straight but will appear to loft higher than expected.

Aside from the visual disorientation, there is a physical effect, too: Coriolis force makes people and animals feel sick. This is due to its effect on the fluids in the inner ear, which give us our sense of balance. Turning one’s head rapidly or rounding a fast corner on a bicycle in a rotating settlement causes these fluids to move in ways that our brains were not designed to interpret; we feel dizzy, our vision becomes distorted so that stationary objects seem to move, and we feel an effect like seasickness or spacesickness (more appropriately called “Space Adaptation Syndrome”). Elderly people whose sense of balance has deteriorated can become debilitated by these effects.

Although our bodies and brains are extremely adaptable, there are limits to how much adapting we can do. If space settlement residents stayed in the same equivalent gravity all the time, they could eventually adjust to higher rotation rates. But that is not what they will do. Many will work in the micro-gravity manufacturing facilities, laboratories, and docking bays for visiting ships; they will “commute” daily or even several times per day between zero gravity and one gravity. Some will return to the non-rotating sections for zero-gravity recreation and games. They must re-adapt frequently to both zero gravity and rotating environments. In time, nearly everyone who is motivated to live in space can make these adjustments with rotation rates of one rpm. They will feel more comfortable, however, living with lower rotation rates.

Although solar energy is abundant in the inner solar system, collecting enough of it to provide electricity for a large population of humans is a non-trivial matter.

The first comprehensive studies of large-scale solar power generation in space were conducted over three decades ago. Legend has it that the concept of Solar Power Satellites was first envisioned by Dr. Peter Glaser as he sat in an early-1970’s gas line. At the time there was an Arab oil embargo, an energy crisis, and global concern about increasing use and decreasing availability of energy. People sometimes waited hours in lines at the few stations that had not run out of gas, sitting in cars that got 15 miles per gallon and had a range around 200 miles. There was plenty of time to think.

The idea of using solar cells to generate electricity in space was nothing new. Communications satellites had been doing that for years. Indeed, the most distinguishing characteristics of most Earth-orbiting satellites, even today, are their arrangements of solar cells. A common configuration is a cylindrical shape with the entire exterior covered in purplish-blue solar cells. Non-cylindrical satellites have large “wings” covered with solar panels. The crewed laboratories Skylab, Mir, and International Space Station all had or have large solar cell arrays that generate power for the satellites’ use.

The difference between existing satellites and Solar Power Satellites (SPS) is that an SPS would generate more power–much more power–than it requires for its own operations. Studies in the 1970’s by Glaser, NASA, and major corporations produced a myriad of design concepts. Their single most distinguishing characteristic is that they were huge-with up to 60 square miles of surfaces covered with solar cells. The figure shows an example of a concept developed during that time. A common goal of designers was to put enough solar cells on a structure in space to generate 10 gigawatts, approximately equal to the output of ten nuclear power plants. The idea was not entirely far-fetched; advantages over Earth-based solar power facilities were that the GEO locations typically proposed for SPS were almost always in sunlight and only rarely eclipsed, and the amount of energy available to a unit area of solar panels is 6 to 15 times greater than for the same area of solar panels on Earth, because sunlight in space is not filtered by atmosphere.

Once having generated electricity in space, however, it is necessary to get the power to where it is needed on Earth’s surface. The solution selected in the 1970’s, and still valid today, was to convert power into microwave energy that could be beamed to Earth’s surface. Microwaves pass through atmosphere, clouds, and precipitation with no loss of energy. Experiments on Earth with transmission and reception of energy converted to microwaves proved the concept. The antennas designed to transmit the huge amounts of SPS power were, however, huge (although dwarfed by the sizes of the solar panel arrays). Typical designs were a half mile or kilometer across; examples can be seen near the ends of the design shown in the figure.

Antenna sizes were probably dictated not so much by constraints of materials or technology as by concern for safety. A highly concentrated power beam would be a tough sell for people concerned about airplanes being zapped out of the sky or entire migratory flocks of birds being cooked en route. Large antennas in geosynchronous orbit, combined with the physics of an expanding microwave beam, resulted in receiving antenna (rectenna) designs six to eight miles across (10 to 13 kilometers), with maximum intensity at the center of the microwave beam less than five times greater than standards for kitchen emissions from a microwave oven. These facilities would convert the microwaves back to energy, and contribute their power to the energy grid in the same manner as a hydroelectric dam, coal-fired plant, nuclear reactor, ground-based solar facility, geothermal plant, or field of wind turbines. The benign radiation environments under these widely-dispersed beams would enable air traffic, radio, TV, and birds to continue their normal activities with no impediments. Even so, safety concerns (and the importance of not wasting power by beaming it away from the rectenna) dictated that the microwave beam was kept centered on the target rectenna by a “guide beam” reflected back to the SPS. Because the rectenna structures would be ten to twelve feet off the ground and designed to capture all of the microwave energy in the beam, the land under the rectenna would be available for agriculture. It was speculated that birds would avoid the rectennas during Summer months and congregate in them during Winter months, because they would experience a slight warming sensation. Dr. Peter Glaser himself offered a standing bet that he would provide fine wine and salad to the person who would eat the first fowl to venture into the microwave beam; his point was that the bird would be very much alive and unwilling to be eaten.

Dr. Glaser hasn’t yet had an opportunity to pay off on his wager, because no SPS was ever built. As oil production increased, cars used less of it, and prices came down, the interest in SPS waned. There was a low-level continuing interest in energy-dependent countries like Japan, but the concept faded from the public vision.

Until recently. Occasional threats to energy supplies, projections that coal and oil reserves will eventually be depleted, and concerns that burning hydrocarbons contributes to environmental damage are providing inspiration for new interest in Solar Power Satellites. New technologies have, however, changed some of the parameters involved in constructing a viable SPS. Solar cells can now convert sunlight to power much more efficiently than when the first designs were envisioned, resulting in new designs about half the size of the originals for the same amount of power generation. Even so, any viable SPS of the future will still be huge.

The implication for a space settlement is that the need for power–assuming it is provided from a solar source–will be a significant factor in the settlement’s configuration and a major feature of its design. The need to orient solar panels toward the sun or a rectenna toward its power source will determine how the entire settlement is positioned in space. The Space Settlement Design Competition organizers anticipate that future non-industrial human communities will require about 10 megawatts per 5000 people. Industrial communities will require more. The physics of microwave transmission have not changed. Whether a space settlement is designed with its own solar panels or with a rectenna for receiving power generated elsewhere in space, the equipment for providing power will be a major part of what is seen when the settlement is viewed by approaching spacecraft.

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In the Space Settlement Design Competition, you and your team members are emulating the way companies work when they are bidding to win contracts for new business. Preparation of a winning proposal is a large, complex task, which requires a variety of skills. In industry, the technical skills required to win and perform a contract exceed the abilities of individuals working alone. Hundreds, thousands, or even tens of thousands of employees must work together to achieve the goal of producing products that do what they are supposed to do, are ready when promised, and can be made for the predicted costs. Each piece of the design may be created by different people or groups, yet the entire integrated product must operate as if it were one thing.

Just collecting skilled people in a building and telling them to go to work will not make a product happen. In the Design Competition, just collecting your team in a room will not make your design and proposal happen. Each person has different skills, different priorities for what is important in the design, different ideas about what the design should include, and even different perceptions about what the RFP requests. If your team is to produce a winning proposal, design decisions must be made, team members must agree on how all the components fit together, and disagreements must be resolved.

Teams in industry go through the same processes. As companies grew and products became more complex, companies invented organizational hierarchies that enabled their teams to create designs and produce products without becoming paralyzed in disagreement and personal agendas. Many different types of organizational structures have evolved, to meet the needs of many different companies. Huge organizations that produce a single, large product line (like an airplane or spacecraft) have different organizations than huge companies where most employees work on several different small projects. Successful companies find organizational structures that work. Some companies fail because their organizational structures inhibit communication or suppress good ideas.

The business of making organizations work is called management. Being a manager is not like being King. The modern manager feels uncomfortable being considered a “boss”, and must behave more like a leader. The manager’s task is a combination of coaxing employees to be innovative, committed, and productive; keeping customers happy and enthusing them to buy more products; assuring the press and the public that the company behaves responsibly; balancing income and expenditures so that the company makes a profit and the stock value increases; and using technical knowledge to make or approve product decisions, resolve design disputes, and improve production processes. Each individual manager will have more or fewer of each of these responsibilities–and will take the blame for anything perceived to be imperfect about the work done or decisions made by people reporting to him or her. It is hard, frustrating, demanding work. It is not unusual for managers to work eight hours per day attending meetings and tending to their employees’ concerns, and another four hours per day doing their own work–typically preparing presentations for meetings, reviewing reports and budgets, getting smart for technical decisions, and making plans for the future of the organization.

Some of these management challenges will be experienced by teams in the Space Settlement Design Competition. No one person will prepare all aspects of the design, or write all of the text in the proposal. Individuals must be assigned to create every part of the design, write every section of the proposal text, and prepare each figure and chart. There will be some parts of the task nobody wants to do; management must find a way to get it done. There will be differences of opinion or conflicting ideas about designs; management must resolve them. The proposal may have too many pages, the dimensions of adjacent parts of the design may not match, two different functions may need to go in the same place, the cost data may have missed a few parts of the construction process. It all has to be fixed.
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The Competition co-founders define an organization structure for the Finalist companies (companies are made up of trios of Finalist Teams) that at least provides a structure for resolving differences; it is shown in the Figure. This is a simplified version of a very basic and traditional organizational structure that was common in aerospace companies during the 1960’s and 1970’s. Each of the engineering departments roughly corresponds to the requirements described in a section of the RFP. A Director in charge of each engineering department is expected to make sure everything in the corresponding RFP section is addressed in the design and documented in the proposal. Each engineering department, however, also must communicate with the others: Structural Engineering must allocate a part of the settlement for facilities (e.g., homes, water treatment, robot maintenance) designed by the other departments, every department needs computer and robot services designed by Automation Engineering, and so on. It is the responsibility of the Engineering Vice President to make sure this communication happens, and to resolve design conflicts (e.g., Human Engineering may want a lake in a park, and Operations Engineering may have difficulty transporting enough water to fill the lake). The Marketing Vice President is responsible for making sure the entire Proposal comes together and coherently describes the space settlement design (i.e., sells the product). Marketing needs to get the data from Engineering, and may want to influence the design or enhance text to produce a more sellable product. If these disputes cannot be resolved between Engineering and Marketing, the President must either find a consensus, get a compromise, or edict a decision. The President has overall responsibility for making sure everything gets done, and the proposal is completed by the deadline. This includes assigning responsibility for meeting requirements in RFP sections that don’t correspond to engineering departments. This process will probably include setting schedules that identify deadlines for finalizing design decisions, completing text sections, reviewing all the materials, resolving incompatibilities or “filling holes”, and sending the completed product to the judges.

Industry relies on professionals who are experts in different fields to work on design details, and engineering managers with more general knowledge to integrate the pieces together. Nobody in the organization needs to know everything required to complete the design process; the organization does, however, need both “jacks of all trades” and “masters of one”. In the Finalist Competition, this situation is emulated by having every student attend one of five training sessions, depending on each person’s position in the organization chart. The Technical Sessions on Structural Engineering, Operations Engineering, Human Engineering, and Automation Engineering provide background information and teach skills to help team members in preparing the corresponding parts of the design. They also learn how every department both owes products to each of the others, and needs to get products from each of the others. In the Management Session, Presidents and Vice Presidents of the four competing companies learn about customer priorities, management responsibilities, and interpersonal situations that will have to be resolved in order for companies to achieve design decisions and produce briefings that will be presented to the judges. Qualifying Competition teams can emulate this kind of knowledge distribution, by assigning some individuals to research and understand certain aspects of the design in depth, while others seek general understanding of the space settlement design priorities. Managers can do research to help themselves perform their tasks, too; books like The Complete Idiot’s Guide to Project Management, The Brass Tacks Manager, and Eliyahu Goldratt’s novels The Goal and The Critical Chain can provide background information.

For the Finalist and Semi-Finalist Competitions, a real manager from industry or government is assigned to serve as CEO of each competing company, with responsibilities to help keep team members communicating and focussed on the goal to prepare and present a design by the deadline. Your team is also welcome to recruit people who are managers in real life to serve as CEO or provide other assistance in your preparation of a design and proposal for the Qualifying Competition. The Teaching Materials section on “Mentoring Teams” describes how non-students can participate with your Space Settlement Design Competition team. Please remember, however, that your team will be assigned a new CEO if you are invited to the Finalist Competition.

Alumni of Space Settlement Design Competitions tell us that achieving effective communication is often the most challenging task of the weekend. This is true in industry, too. It is probably also true for most Qualifying Competition teams. If your team managers concentrate on effective communication, every other aspect of the design process can be accomplished more smoothly.

A key attribute of Space Settlement Design Competition scenarios is that the first settlement is built very quickly–in about a dozen years. The real reason for this is that the Competition organizers want to offer a chronology of widely varying scenarios that participating students could see during their working careers, or at least during their natural lifetimes. It would be less interesting for students to work on a space settlement design planned to operate a half-century after they expect to retire.

The Competition organizers do believe that once the first settlement is built in space, and a mining, refining, manufacturing, and transportation infrastructure is established, economics and ingenuity will enable large settlements to be built in fewer than 15 years. This is akin to a “Southern California freeway phenomenon”, wherein a new freeway is built into a remote area with very little population, and in just a few years the freeway is clogged with traffic because the access it provides enables communities and businesses to be established on its flanks. Having infrastructure in place makes it easier to get more infrastructure in place.

But the first settlement is different. The first settlement starts with nothing. In Earth orbit there is vacuum, a variety of environmental hazards, unrealized access to extraterrestrial resources, and solar energy. Nothing more. There is no scheduled transportation service, no port to put into for supplies or repairs, no grocery store, no refueling station, no building supply store, no dirt to grow food in, no water. Nothing.

We do offer an incentive for why it would be important to build the first settlement quickly. Whether or not one believes that global warming is a real threat, if conclusive evidence were provided that it would cause global extinction within a lifetime, then unlimited resources would become available to stop it. Studies have shown that a solar shield at the Earth – Sun L1 libration point (a point in space about 900,000 miles away where orbital mechanics enables a satellite to stay in place between the Earth and Sun) need only reduce sunlight by 0.5%, and the entire global warming threat goes away. The shield would have to be almost the size of Texas. The Space Settlement Design Competition scenarios are based on the premise that the first space settlement would be built as a construction base for such a solar shield. The urgency of saving the Earth would put a high priority on building that space settlement as quickly as possible. So, how do we propose that the very first space settlement–named Alexandriat in the Competition–could be built in only a dozen years? Even the optimistic NASA studies of the 1970’s predicted a 22-year construction schedule for the first settement.

The simple answer is that construction happens quickly because it has to happen quickly; the situation for the Earth is urgent. The only question for the designers is HOW to get it operating quickly. We start with the assumption that Alexandriat doesn’t have to be beautiful or elegant or even durable enough to last longer than the construction process for the solar shield. It has to be functional, it has to be self-sufficient, it has to be comfortable enough that the people living there won’t go crazy, and it has to provide facilities for building the solar shield. Anything else is fluff.

We also add an assumption that the solar shield–with the space settlement required for its construction–is such a high priority for the world’s peoples that conventional practices of protecting company proprietary data and national technologies are set aside until the project is completed. As in World War II, innovative designs developed by one company are licensed to other companies and even other nations, in order to get the job done. No one company could fulfill a contract to complete this project. Even with unlimited budget, there are not enough qualified engineers and technicians in any one nation who could be made available to complete this project quickly. The effort must be inter-company and multi-national. Money may be no object, but the number of available engineers and technicians limits how fast it can be spent.

The Foundation Society initiates the project by assembling a team of top managers and engineers from established aerospace companies. The stakes are high, so virtually anybody who is needed can be excused from current duties. The core team is relatively small, to enable quick decision-making; perhaps five executive managers, ten technical managers, and 100 engineers. Before beginning the design process, this team establishes design requirements and guidelines that make the settlement easier to build. Artificial gravity of 0.5 g and a 10 psi atmosphere are entirely adequate for human existence, but these reductions from Earth surface conditions reduce the stresses in the structure so that construction is more feasible. To save design time, the basic torus shape described in the 1970’s studies can be defined as the baseline. The details, however, are completely new–different materials, different construction techniques, modifications to accomplish the solar shield construction project, updated interior features.

Simultaneously, a Human Resources team arranges for the employees who will work on the project. The most challenging aspect of building a huge project quickly is hiring and coordinating the tens or hundreds of thousands of people needed to make it happen. With nearly full employment of technical people in the United States, Canada, Western Europe, Australia, and Japan, the necessary employees must be found elsewhere. The companies of these nations are contracted to do more of what they do well–in support of the project, they build and operate more assets that it is known will be needed: launch vehicles, rocket engines, special-purpose satellites, space tugs (modified for long-distance cargo deliveries), and space stations. They conduct the research to develop new materials, control systems, robots, and improved manufacturing methods. Although no crewed lunar landing craft has been built since the early 1970’s, corporations open up their vaults of proprietary designs and reveal that valid conceptual designs exist to augment Constellation program vehicles; they were just waiting for somebody to pay for development. Construction of all aspects of needed transportation infrastructure is underway within seven months.

The vast majority of effort on the settlement and solar shield, however, is the “grunt work” of detailed designing, analyzing, testing, building, transportation planning, and assembly scheduling of the required components. For these tasks, the Foundation Society taps into vast reserves of underemployed but well-trained and highly skilled individuals in Russia, Eastern Europe, India, Pakistan, China, Brazil, and several other countries not typically considered at the forefront of innovative space technology development. Specialized training is provided as required, sometimes in cooperation with universities. Coordinating all of these efforts worldwide is a huge task. The core team compartmentalizes the requirements into portions that can be accomplished by the various teams world-wide. They very specifically define the interfaces between the pieces that are designed by the different teams. They travel extensively to assure that each team has the information it needs, and is on schedule and producing its own products as expected. As each team finishes a part of the project, another part is assigned. Early tasks define details that enable construction to begin on the overall shell of the structure and the solar shield manufacturing facility. The designers proceed into deeper and deeper details–for example, electrical power distribution, sewage processing, farming techniques; then street maps, municipal buildings, and parks; finally the details inside individual businesses and residences.

Quick construction of the space settlement requires development of new techniques and unconventional methods. Transportation from Earth’s surface to space is a bottleneck, so utilization of non-terrestrial resources speeds the process. Some of the tools proposed in the old NASA 1970’s studies are “dusted off” and improved, most notably the electromagnetic mass driver concept for efficiently launching materials off the moon. Refining vast quantities of materials in space requires time to develop zero-g refining processes and build the refineries, so use of materials in their natural state also speeds the process. The ideal situation would be to build the settlement from dirt. And, as much as possible, that’s how it’s done.

Dirt has been proven, by several methods, to be a fine construction material for structures in compression–arches and domes that are designed to keep their shape against the pull of gravity. Acceptable structures for a mining camp on the lunar surface can be built in a matter of days, and the construction technique is simple enough that it can be automated with robots. “Superadobe” construction is accomplished by compacting dirt–any kind of dirt–into long tubes of flexible material. Rugged fabric that can handle the space environment was developed for the Mars Pathfinder mission in the mid-1990’s, and with some minor adjustments to the manufacturing process, miles of lightweight superadobe tubing are available as soon as the necessary vehicles can ship it to the lunar surface. Robots are programmed to fill the tubing and stack it, layer upon layer, to form domes for buildings; the process is much like stuffing sausage casings. Each layer of superadobe is about six inches high and two feet thick. After the domes are formed, some additional shielding is provided by piling loose dirt on top of them, and they are sealed to be airtight with a glaze on the interiors. The additional dirt also provides insulation to protect the interiors from the extremes of lunar temperatures.

After the lunar base buildings are completed, the robots continue to pack superadobe tubes. When the mass driver is completed, it is immediately employed in the business of launching superadobe. The technology of electromagnetic levitation that makes the mass driver work had not been implemented on a commercial scale when the 1970’s NASA studies were conducted; now, essentially all that is required to build a lunar mass driver is to deliver components of the tracks on which high-speed trains operate, and to modify and adjust the power and control systems for this new application. As proposed in the 1970’s NASA studies, the mass driver only sends material to a collection point in space, from which it is transported to the space settlement construction site. One of the design teams conducts a “trade study” to optimize the size of each mass-driven package and the frequency at which packages are sent; another team identifies an easy way to bind each superadobe package so it will stay intact through the launch process (the 1970’s study proposed launching 40-lb packages at the rate of one or two per second; larger packages are preferred to enable longer lengths of superadobe to be sent in each package). The mass driver requires a lot of power; continuous solar power is acquired on the moon by building at one of the poles.

In order for superadobe to be useful as a construction material for the space settlement, however, a means must be found for keeping it stable in tension–the settlement’s rotation puts forces into the outside surface of the structure that act to pull it apart. Some of this force can be reacted by using a superadobe tubing material that is exceedingly strong in tension. Only the outside surface needs this capability, however, so it is not necessary to go to the expense of making all of the tubing from more exotic materials. It is sufficient to build a mesh or net of high-strength fibers–perhaps similar in appearance to chicken wire–to encase the outer surface of superadobe. More stability is acquired by weaving the superadobe to form the torus; the relatively short lengths that can be launched by the lunar mass driver are as strong as continuous superadobe coils when they are woven. The necessary wall thickness for radiation shielding is acquired by weaving multiple layers of superadobe.

Also adopted from the 1970’s studies is the location for the first settlement, an orbit around the Earth-Moon L5 libration point. It’s closer and easier to get to than the solar shield construction location, and there are advantages for future infrastructure development. Only the materials for the solar shield, with a minimal construction crew, need to go all the way to the Sun-Earth L1 libration point for solar shield assembly.

The construction process for the settlement starts with minimal materials. A small spherical hub is built as a “construction shack” for the engineers and technicians who are responsible for assembly of the settlement. They attach thick kevlar ropes (coated to prevent deterioration by the sun) to the outside of the hub. The first narrow woven strip of superadobe (reinforced to withstand tension) is over three miles long. Its ends are joined in a hoop and the ropes from the hub are attached at regular intervals. When small ion engines spin the hub, the ropes tighten, and a spindly mile-wide “wagon wheel” takes shape. From that point, the spokes and rim are built up to their final dimensions as more material arrives and can be added. Living quarters on the rim are added, sealed, made habitable, and populated in small sections, so that at various stages of construction the structure resembles a large necklace of chunky blocks. After several hundred residents arrive, the solar shield manufacturing area is added to the hub, so that Alexandriat’s primary function can be fulfilled as quickly as possible. Construction is automated as much as possible, with robots programmed to assemble sections of superadobe into the torus sections and seal them in preparation for use.

Some other materials required in large quantities are also acquired from the moon. They do, however, require refining of the native materials, and ores are harvested from various lunar sites to acquire the desired elements. Oxygen, silicon, titanium, aluminum, iron, magnesium, calcium, and sodium are present in significant quantities on the moon, all bound up in oxides. Separating the components can be a difficult business, especially when rare (on the moon) catalysts like carbon are required for conventional processes. The elements are there, however, and unleashing thousands of creative chemists world-wide inspires some breakthrough separation and refining technologies. Silicon is made into solar cells; sodium makes a fine reflective coating for reflector mirrors; composites, glass, and ceramics are made from several of these materials; and each of the metals is used in appropriate applications. Composites and ceramics are easier to make from lunar materials than metals, and are used for most interior applications–walls of housing units and other buildings, furniture, plumbing and fixtures, bodies and chassis of vehicles for interior use, paving for streets and walkways, doors, cabinets, housings for computers and other equipment, robot bodies, and components of common appliances. As many products as possible are made from lunar materials to reduce the imports required to be launched from Earth. Some of the most mundane materials cause the greatest challenges, and dozens of teams work simultaneously until a solution is found for each–processes are developed to make cloth, string, paper, inks and dyes, flexible tubing and insulation, bicycle tires, paint, coatings for various uses, adhesives, cleaning agents, and other products either exclusively or primarily from lunar materials. With the exception of station-keeping motors and computerized control systems, the entire solar shield is constructed of lunar materials. The importance of the assignments brings out the utmost creativity in every person working on them, and miracles occur.

The most difficult substances to acquire from the moon are ironically the ones that are most common on Earth, air and water. At first, there is no choice; huge quantities of air and water are transported from Earth. Recycling and reclamation are refined to an art form; any losses must be made up with very expensive and time-consuming shipments. Ultimately, technologies are developed to divert small comets and asteroids to augment lunar resources.

With the introduction of microbes, lunar soil provides suitable growing media for agriculture. The early diet of Alexandriat’s residents is carefully planned to yield the most nutrition possible for the least amount of land area, resources, growing time, and risk of crop failure. Yield per acre is increased by use of hydroponics for many crops. Quick growing times for vegetables, squash, and some berries causes these foods to be much more common in the early diet than grain-based breads and pastas. Recipes adapted from primitive subsistence cultures provide good food that can be grown with less expenditure of resources. Rabbits and chickens augment lentils and beans as a source of protein. With time, a greater variety of foods is produced in the settlement, but highly processed foods like most breakfast cereals and salted snacks require manufacturing resources that the settlement can ill afford to expend on alternative flavors and textures of calories. A few tins of Pringles tucked into the precious weight allowance of a passenger from Earth are cause for a party at Alexandriat.

With commitment, cooperation, virtually unlimited budget, and a lot of luck, it can all come together in a mere dozen years. Humans have done it before and have legends to prove it: the P-51 Mustang went from concept to production in just months during World War II, one of Henry Kaiser’s companies built an entire ship in one day, the Apollo project went from a Presidential speech to a lunar landing in less than a decade, the Trans-Alaska Pipeline went from idea to completion in 12 years (only three years of actual construction). And the most amazing thing happens when these miracles occur: people accept them as normal events. Some of the technology stretches that build Alexandriat are adopted to improve processes on Earth. The influx of income into Third World countries raises the level of prosperity as economies are jump-started. Teams of engineers that cause miracles to occur for Alexandriat turn their attention to miracles that need to be performed at home. Perhaps more importantly, great human achievements inspire people to realize that they really can create miracles. When that happens, anything is possible.

Mars Areological Research Surface Utility Vehicle (MARSUV) Exercise

The following pages provide materials for a miniature version of a Space Settlement Design Competition scenario, in which participants design a vehicle for use in exploring the surface of Mars. This could be a design project for a small group, with a design process lasting as little as an hour, and concluding with a presentation about the design. It could be a competition lasting a few hours or half a day, with presentations by the competing teams and selection of a winning design. It is intended to be a small, self-contained exercise that can be conducted quickly and without additional reference materials. It is not recommended that these materials be used for a design exercise or competition lasting for a day or more; with more time, design teams can get into issues that require more extensive reference materials (e.g., daily quantities of food, water, and waste associated with humans; construction techniques and sources of materials; maps of Mars to determine likely terrain a surface vehicle would encounter).

The MARSUV materials provide information about infrastructure presumed to be available on Mars in 2051, and some examples of future technologies that may be available at that time. Background material about the customer organization is provided for context-why would anybody want to go to Mars, and how would they get the money to live in space? A list of Mars attributes summarizes some of the challenges associated with designing equipment to operate on the planet’s surface. The final page is the Request for Proposal (RFP), or description of requirements that the customer wants the vehicle design to meet. The RFP is arranged to show how four engineering departments could divide the tasks to get the design completed. Note that there is some communication required between the groups handling separate tasks–the departments must communicate their work to each other so that the whole design comes together (e.g., Human Engineering determines requirements for water, Operations Engineering figures out how to provide it, Automation Engineering controls the recycling of it, and Structural Engineering figures out where the systems go in the design).

Remember, the primary reason for doing a design process of this type is to demonstrate techniques for managing a complex task in a short amount of time. It provides a means for developing team-building skills, and shows how tasks get accomplished in industry. Those are hard lessons to learn, but this is a means for having fun during the learning process!

The Customer

The Foundation Society is an organization founded for the purpose of establishing human settlements in space. Its first settlement became operational in 2025, and served as the construction base for the huge solar shield at the Earth-Sun L1 libration point. The solar shield succeeded in reducing sunlight on Earth by 0.5%, reversing effects of global warming that were predicted to have adverse impacts to the world’s economy. The success of the solar shield resulted in enormous financial compensation for the Foundation Society, enabling it to pursue its goal to move increasing numbers of its members into space.

The organization now operates three settlements in Earth orbit and one on Earth’s moon. Each settlement meets residential, business, and recreational needs of between 10,000 and 20,000 permanent residents. Each settlement also provides a unique element of infrastructure for human activities in space: a manufacturing and materials processing center (the "rust belt" of space), a financial and commerce center (a sort of "Singapore-in-Orbit"), a center for research and development of technology (the "Tech Torus", with tenants from several Silicon Valley companies, and the main campus of The University of Space), and a lunar mining and tourist center.

The Foundation Society was a partner in the five commercial Mars exploration missions that took place during the past decade. These missions studied only a few promising sites for mining operations, yet they showed that the abundance of resources on the planet has potential for providing materials for in-space construction projects at much less cost than Earth-based sources. Studies have only begun to address the economics of tourism, science, and inspiration for human creativity in the unique Mars environment. The Foundation Society is now committed to its own ambitious global survey of the planet, which will identify candidate sites for a future surface settlement. The Mars Areological Research Surface Utility Vehicle (MARSUV) will be a critical element of this mission.

The most important construction at Mars is a settlement being built in orbit above the planet by the Foundation Society. Partial operations will begin at this settlement in 2057, and the settlement will be ready for its permanent residents in 2063. The intent of this settlement is to provide a "Port of Entry" for Mars-a place where interplanetary ships will transfer their cargo to landing ships that deliver goods to locations on the surface. This settlement will also serve as a construction base for future settlements on Mars, and will serve as a supply and shipping center for mining operations in the asteroid belt.

Your Company

Marsotronix, Inc., was founded to conduct research applicable to commercial enterprises on the surface of Mars. It began its studies in 2007 as an entrepreneurial partner with NASA for missions to Mars, and has been involved in every commercial Mars expedition. It currently is headquartered in facilities leased from the Foundation Society’s settlement on Earth’s moon. The lunar location enables the company to test its products in a harsh space environment. Suppliers on the moon and at space-based materials processing and manufacturing facilities provide most of the raw materials and components the company requires for its assembly operations.

The company’s early contributions to Mars missions focused on accurate and speedy data analysis to aid in planning of future Mars missions. As its experience, reputation, clientele, and revenues grew, it grew its business base to encompass more of the expertise involved with humans’ relationships with Mars. Marsotronix built the surface structures for the first human crew that landed on the planet and conducted scientific research there. It designed the laboratories in use at the first permanent Mars base, and has had a role in each of the other two bases on the planet. Each base is little more than a collection of radiation-shielded shelters and small labs; due to their vulnerability to maintenance failures, Marsotronix provides a staff technician at each base, to identify maintenance and support challenges before they become emergencies.

The company is at the forefront of innovation for developing technologies appropriate for operations on Mars. It has created automated landing systems that can pinpoint a probe’s position within a few yards; drilling systems that can recover soil, rock, and ice samples from 50 feet below the surface; and vehicles that can safely operate up to 40 miles from their bases. It developed the radio beacons that mark "roads" in the vicinity of the Mars bases; the beacons are placed every half mile and provide both navigational aids for vehicles and communications back to the base. Marsotronix designed the small rocket craft that, in an emergency, can get to almost any location on the planet to conduct a rescue mission, if a suitable landing area can be found.

The most ambitious project undertaken by Marsotronix is a fleet of cycler ships to provide scheduled transportation between Earth orbit and Mars orbit. These large ships will remain in their orbits, with only small adjustments to compensate for perturbations in orbital mechanics. Transfer ships will rendezvous with them in the vicinity of Earth and Mars (the Mars transfer ships will be based at the Foundation Society’s Mars orbiting settlement), unloading imported goods and delivering export cargo for shipment. The first of these ships is completing its first cycle between the planets; others are under construction and will enter service during the next five years.

Mars Environment

Although considered this solar system’s best opportunity for productive human settlement away from Earth, Mars in 2051 is still a very hostile place, at the frontier of human existence. The few score of human visitors have confirmed what robotic probes revealed near the end of the last century: it is cold, desolate, dangerous, eerily beautiful, and seductively beckoning humans to come and plant roots.

Gravity 38% of Earth’s
Distance from Sun average 141.6 million miles (Earth is 93 million miles)
Minimum Energy Orbit Travel Time from Earth 259 days
"Windows" for Optimum travel from Earth about one month, at two-year intervals
Length of Day 24 hours, 37 minutes
Length of Year 687 (Earth) days
Diameter 4,218 miles
Surface Area approximately equal to Earth land area
Magnetic field insignificant
Atmosphere less than 1% of Earth’s pressure, mostly carbon dioxide
Surface Temperatures average -30°; range from -100°F to just above freezing
Radiation Environment equivalent to interplanetary space from above
Weather Some clouds, winds to hundreds of miles per hour
Storms winds can cause months-long global dust storms
Seasons due to axis tilt and elliptical orbit, southern seasons are more extreme-southern winter is longer and colder; southern summer is shorter but warmer
Surface composition ample silicon, aluminum, iron, magnesium, and calcium
Resources concentrations and accessibility of ores and useful minerals similar to Earth
Water substantial quantities, mostly frozen underground in northern basin
Terrain primarily rocky plains, with plentiful quantities of very fine dust
Topography Large, deep basin in the northern hemisphere
Heavily cratered highlands in the southern hemisphere
Several very large and tall volcanic mountains
A few very large ancient river valleys, with steep canyon walls up to two miles high
Polar Caps northern polar cap water ice; southern polar cap mostly carbon dioxide ice
Moon: Phobos 13 miles across
Orbit altitude 5,800 miles from Mars center
Orbits three times per Martian day
Moon: Deimos 7.5 miles across
Orbit altitude 14,600 miles from Mars center
Orbits once per 1.3 Martian days
Hazards to Long-Term Operations Dust causes premature wear and breakdowns of mechanical equipment
Wind-blown dust at high speed has sandblasting effect on surfaces
Dust storms restrict visibility and reduce effectiveness of solar cells

For a good read with some great information about Mars, check out Kim Stanley Robinson’s trilogy, Red Mars, Green Mars, and Blue Mars.

Request for Proposal

  • Date: February 2051
  • Re: Mars Areological Research Surface Utility Vehicle (MARSUV) Contract


This is a request by the Foundation Society for contractors to propose the design of a vehicle to enable long-term surface exploration on the planet Mars, for the purpose of identifying candidate sites for a future settlement on the Martian surface.

Statement of Work

Basic Requirements – The MARSUV must provide a safe and pleasant environment for a crew of eight engineers and scientists to engage in exploration missions for periods of up to six months with no resupply or support. The vehicle will be designed to enable the crew to go out on the surface in space suits.

Structural Engineering Requirements

  • Define exterior design — provide a drawing showing vehicle size and shape
  • Show installations on the vehicle of all major components
  • Show arrangement of interior functions
  • Show tires, treads, or other means for providing mobility on the planet surface
  • Identify locations of storage compartments
  • To enable transportation from construction in Earth orbit to landing on Mars, MARSUV must fit in a standard 15 foot square by 30 foot long cargo container, and weigh less than 30,000 pounds

Operations Engineering Requirements

  • Identify means for providing electrical power
  • Provide engine design, and identify fuel and storage needs
  • Identify means for providing communication
  • Provide heating, cooling, environmental control, and recycling systems
  • Determine means of providing food and water for the crew during MARSUV missions

Human Engineering Requirements

  • Provide "cockpit" enabling crew visibility and adequate control of the vehicle
  • Design furniture, meeting and dining space, and sleeping areas
  • Design kitchen and hygiene areas
  • Specify requirements for food, water, and clothing for six-month mission durations
  • Provide opportunities for crewmember privacy

Automation Engineering Requirements

  • Provide navigational systems for location, route selection, and hazard avoidance
  • Computer must monitor vehicle status, and control atmosphere and recycling functions
  • Computers provide data processing, communication, and entertainment for crew
  • Computer and robotics systems will aid collection and analysis of samples
  • Automate tasks that would be dangerous or boring for the crew