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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. 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. |
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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 liberation
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 settlement.
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.
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; 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 providing 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. |