Living in Space

Living on green islands in Space

By Henry Kluytmans.

Foreword.

I had barely started on high school when I accidentally happened to stumble accross a book named "The High Frontier" by Gerard K.O' Neill. This book impressed me enormously. After reading this book I had to convince everybody what kind of mindbogling constructions, we were capable of building, even with the available technology. I was convinced that eventually humanity had to move to space, and I hoped this would happen as soon as possible.

In this book it was predicted human habitats in space would probably be build between 1995 and 2025. This time prediction appears to have been chosen to optimistic. A probable cause for this optimistic prediction is the energy crisis in the 70's (at the time this book was written), and induced by this the pessimistic expectations promoted by the Club of Rome (Limits to growth).

One of the economic motors, which was presumed to drive the immigration to space, was the production of cheap energy in space (using solar-energy satellites). The industry was predicted to automatically follow these sources of cheap energy, and with it the people required to run this industry. Regarding the pessimistic expectations at those times (with respect to the Earth's energy reserves), solar energy production in space would be economically interesting in a short time. But some years later, it appeared, the amount of natural energy reserves on Earth were much less critical then assumed before. Regrettably, at this moment, solar-energy from space has still not yet become economically attractive, but this will change in the future....

I'm still convinced humanity will move to space in the long end. With continuing exponential growth of the human population and of the energy consumption, there seems to be no other option. But it seems we will have wait a little longer. At this moment, living in space, is not yet economically viable. However with the continuing advance of technology the costs of transportation to space will decline, while economic and environmental drives will increase.

Maybe a totally different approach to transportation to space is required to really make it cheap. A completely new technical concept of transportation like the roton or the orbital tower. Or maybe a commercial mass exploitation of space-travel.

View inside a space habitat, a remarkably Earthlike scenery ! The population density in this habitat is clearly not at it's maximum.

A residence in space.

Most people still think living in space will mean keeping residence in gray metal boxes. In fact living in space will be just as convenient as living on Earth, or even more. Otherwise only very few people will be willing to really live there. A residence in space will therefore appear very similar the ones here on Earth. They will look exactly like the average houses we're so used to. They will have a gardens, and if desired by the owner, he will even be able have to put a pond in his garden. There will be different plants and animals. And looking up into the sky you will see the sun shining through the clouds!

How will this be realized technically ?

Outside view of a space habitat (O'Neill Island 3). The tilted rectangles are mirrors to reflect the sunlight to the inside. These mirrors will rotate as the cylinder so sunlight will always be reflected inward from the same angle.

An enormous bottle!

O'Neills concept of a space habitat is an air-thight bottle with a length of 30 kilometers and a radius of 3 kilometers. This bottle will look like a cylinder with two spherical endcaps. The outer skin of the bottle will be build of alternating rectangles of land-area and transparent window rectangles. The last will permit sunlight reflected by the mirrors to illuminate the opposing landareas. The bottle will rotate around it's cylindrical axis once every two minutes. This rotation will generate a centripetal acceleration equivalent to the gravity at the Earth's surface (just like an ordinary centrifuge). Air will be pumped in, untill at the landareas an air pressure of one bar is reached. (However, at the axis in the middle of the cylinder the air pressure will be considerably less.) At a height of approximately 500 meters above the landarea, clouds will form automatically from the excessive water vapor present in the air (depending on the temperature and humidity). Also in very large buildings on the Earth (like the Apollo rocket assembly hall at Cape Canaveral) clouds are known to have formed during special circumstances. The rectangular landareas will be covered with a layer of dirt. In this a layer park-like flora will be planted. And finally ordinary houses, which look very similar to the ones on Earth will be erected.

Cross-section of the space habitat (schematic dimensions used)

The amount of habitable surface area inside such a space habitat will be approximately 270 km^2 (counting only the areas with 1G gravity). There has been calculated that this surface area should be sufficient to accommodate six million people. Note that this area is not including the surface required for agriculture, industry and transport facilities. The production of food (agriculture) will take place in smaller separate cylinders. The industry will also be placed outside the living habitat. The gravity generated in the living habitat can be a disadvantage for industrial processes. Also high transportation costs, possible pollution, etc. are reasons not to place the industry inside the living habitat. The public service companies and institutes (shops, townhall, library, etc.) can be placed beneath groundlevel, and therefore do not take up any precious surface area. Also situated beneath groundlevel will be several metrolines (probably using magnetic levitation as means of propulsion). The train stations will be located to render the shortest distance from any point in the living areas less than 500 meters (i.e. walking distance), therefore only pedestal and bicycle paths are required for transport of the residents.

Suppose every residential accommodation will house on average three persons. (The space habitat will also contain families with children.) Suppose on average a house has two floors with a surface area of 5 by 10 meters and a surrounding green area of the same size. With these dimensions more than 25% of the total habitat surface area will be left available for public parks and pedestal loans. If part of the accommodations will be build as multiple floor apartment buildings (for people who stay at home less often) even more surface area will remain.

We have not considered the living area in the spherical endcaps of the cylinder. Here the effective gravity will decrease from 1 Earth gravity to 50% (0.5G) at a location at a 60 degrees angle. However lower gravity can be a considerable advantage for the elderly and the handicapped people (and for people with some special diseases). Probably this will be an ideal place for elderly houses and hospitals. Also it could be a fun place for practicing sports like : 0.1G swimming or 0.2G ballet . . . etc.

The placement of agriculture in separate smaller cilinders has several advantages:

Plant-life is more resistant to mutations caused by harmful radiation than humans. Therefore the agriculture cylinders will require less shielding against radiation than the living habitat. They can have a lighter construction and thus be cheaper.
For plant-life the gravity will not have to be 1G. This also results in a lighter construction.
The appearance and position of the solar disc is of no concern to plant-life. Therefore the mirrors required for the reflection of sunlight can have a less complex thus cheaper construction.
Atmospheric constitution (proportion of the gases oxygen, carbon-dioxide and nitrogen) can optimized for plantlife. The same can be done for temperature, the amount and type of sunlight, length of days and seasons, etc.
Because of the total separation from the living habitat the probability of contamination by humans is extremely low. Think of insects, bacteria and viruses carried along by humans and animals. In the rare case of contamination the complete agricultural cylinder can be decontaminated by increasing the temperature for an extensive period (to about 200 degrees Centigrade).
Because of the exactly controlled climate in the agricultural cylinders the yield is much more reliable and greater than rendered by the same amount of surface area on Earth.

Is this all technically possible ?

Using materials produced by conventional technology, a living habitat with the geometry of a cylinder and a diameter of 6 kilometers can be realized (using steal or aluminum). The feasibility can be easily calculated using the same methods as are applied today for designing ships or bridges.

In the future when new materials will become available with a strength equivalent to diamond (or even better) it will be possible to construct cylindrical space habitats with a radius of 500 kilometers. Large window areas like in the constructions described above will not be practical in cylinders of this size. Sunlight will have to be directed inside using different methods. Without large window areas and with a length of 10.000 kilometers the total amount of living area in such a habitat will be 62.800.000 km^2 . With the same population density as the cylinder of 30 km, this will be sufficient to accommodate a thousand billion people !!!

How do we get the construction materials to space ?

Not !

The materials for building these enormous constructions we can obtain from space itself. In space there are known to drift large amounts of material in the form of asteroids and planetoids (rocks in space). A rock of, for example, half a kilometer diameter contains more than sufficient resources for building a cylindrical space habitat with a length of 30 kilometers.

A asteroid rock can be transferred to Earth orbit using a rocket engine based upon an electromagnetic accelerator. As propellant part of the rockmaterial itself can be used.

There has been calculated that the total amount of material present in the asteroid belt between Mars and Jupiter, should suffice to create space habitats with a total surface area equivalent to 3000 times that of Earth.

Another possibility is to exploit the resources of the moon and to shoot them into space cramped into small packets using a electromagnetic accelerator. This is possible because the moon does not posses an atmosphere which will decelerate these projectiles.

Why settle in space.

If humanity continues it's current exponential growth we will have to. Besides there are several advantages of human settlements in space :

Groups with a social and cultural differing attitude can separate themselves from the rest of humanity much easier, because in principle space habitats will be totally self sufficient. Each habitat will be a separate biosphere totally independent from Earth.
The survival of humanity is better ensured against global disasters, because of the spreading of the population over multiple separate biospheres. In the beginning the biospheres are only being spread throughout the solar system, but later they will spread even further. After human settlements are present in space, disasters as result of impact by an asteroid, global nuclear war, or a biological cause are incapable of causing the destruction of the whole of humanity.
The climate inside a space habitat is controlled. Imagine, no weather-forecast, but a weather program!
Much more efficient means of transportation are possible. In stead of being spread over a surface area the population centers are spread out over a three-dimensional space. The average traveling distance, for an equivalent population size, can be much smaller across a part of space, than an equivalent size of surface area on Earth. Furthermore space is airless so transportation can be much faster and more energy efficient (no resistance).

A Solar Power Sattelite being constructed in orbit.

Links for more information :

Island One Society Organization named after the smallest O'Neill habitat.
Space Settlement Plans of the Nasa for space-habitats.
Space Studies Institute Institute founded together with Gerard K. O'Neill himself.
The First Millennial Foundation Organization for colonization of space during the next millennium, suggests settlements floating on the Earth's oceans as an intermediate step.
Molecular Manufacturing Shortcut Group A (faster) shortcut way to start space settlement using molecular nanotechnology.
The Artemis Project Colonization of the moon.
Space Settlement The site of another space colonization enthusiast (with some good stories and lots of pictures).

Back to INDEX Last updated 20-09-97