IN DETAIL PAPER ON SPACE SETTLEMENTS - CLICK HERE, FOR VIDEO CLICK HERE
Who?You. Or at least people a lot like you. Space settlements will be a place for ordinary people.Presently, with few exceptions, only highly trained and carefully selected astronauts go to space. Space settlement needs inexpensive, safe launch systems to deliver thousands, perhaps millions, of people into orbit. If this seems unrealistic, note that a hundred and fifty years ago nobody had ever flown in an airplane, but today nearly 500 million people fly each year.
Some special groups might find space settlement particularly attractive: The handicapped could keep a settlement at zero-g to make wheelchairs and walkers unnecessary. Penal colonies might be created in orbit as they should be fairly escape proof. People who wish to experiment with very different social and political forms could get away from restrictive social norms.
Although some colonies may follow this model, it's reasonable to expect that the vast majority of space colonists will be ordinary people. Indeed, eventually most people in space settlements will be born there, and some day they may vastly exceed Earth's population. Based on the materials available, the human population in orbit could one day exceed ten trillion living in millions of space colonies with a combined living space hundreds of times the surface of the Earth.
What?A space settlement is a home in orbit.
Pictures of Kalpana One.
Lewis One space settlement design.Where?In orbit, not on a planet or moon. Why should we live in orbit rather than on a planet or moon? Because orbit is far superior to the Moon and Mars for colonization, and other planets and moons are too hot, too far away, and/or have no solid surface.For an alternate view, see Robert Zubrin's powerful case for Mars exploration and colonization. Mars' biggest advantage is that all the materials necessary for life may be found on Mars. While materials for orbital colonies must be imported from the Moon or Near Earth Objects (NEO's -- asteroids and comets), there are many advantages to orbital colonies. Advantages include:
Later settlements can spread out across the solar system, taking advantage of the water in Jupiter's moons or exploiting the easily available materials of the asteroid belt. Eventually the solar system will become too crowded, and some settlements will head for nearby stars.
Interstellar travel seems impractical due to long travel times. But what if you lived in space settlements for fifty generations? Do you really care if your settlement is near our Sun or in transit to Alpha Centuri? So what if the trip takes a few generations? If energy and make up materials for the trip can be stored, a stable population can migrate to nearby stars. At the new star, local materials and energy can be used to build new settlements and resume population growth. How?
With great difficulty. Fortunately, although building space colonies will be very difficult, it's not impossible. Building cities in space will require materials, energy, transportation, communications, life support, and radiation protection.
Why?GrowthWhy build space settlements? Why do weeds grow through cracks in sidewalks? Why did life crawl out of the oceans and colonize land? Because living things want to grow and expand. We have the ability to live in space (see the bibliography), therefore we will -- but not this fiscal yearThe key advantage of space settlements is the ability to build new land, rather than take it from someone else. This allows a huge expansion of humanity without war or destruction of Earth's biosphere. The asteroids alone provide enough material to make new orbital land hundreds of times greater than the surface of the Earth, divided into millions of colonies. This land can easily support trillions of people.
A Nice Place to LiveA few features of orbital real estate are worth mentioning:
If there were a major collision today, not only would billions of people die, but recovery would be difficult since everyone would be affected. If major space settlements are built before the next collision, the unaffected space settlements can provide aid, much as we offer help when disaster strikes another part of the world.
Building space settlements will require a great deal of material. If NEOs are used, then any asteroids heading for Earth can simply be torn apart to supply materials for building colonies and saving Earth at the same time.
Power and WealthThose that colonize space will control vast lands, enormous amounts of electrical power, and nearly unlimited material resources. The societies that develop these resources will create wealth beyond our wildest imagination and wield power -- hopefully for good rather than for ill.In the past, societies which have grown by colonization have gained wealth and power at the expense of those who were subjugated. Unlike previous colonization programs, space colonization will build new land, not steal it from the natives. Thus, the power and wealth born of space colonization will not come at the expense of others, but rather represent the fruits of great labors.
When?How long did it take to build New York? California? France? Even given ample funds the first settlement will take decades to construct. No one is building a space settlement today, and there are no immediate prospects for large amounts of money, so the first settlement will be awhile. If Burt Rutan's prediction of affordable orbital tourism in 25 years is correct, however, it's reasonable to expect the first orbital colony to be built within about 50 years.If the first settlement is designed to build additional settlements, colonization could proceed quite rapidly. The transportation systems will already be in place and a large, experienced workforce will be in orbit.
Unless...Space settlement is extraordinarily expensive because launch vehicles are difficult to manufacture and operate. For example, the current (2004) cost to put an individual into orbit for a short time is about $30 million. To enable large scale space tourism by the middle class, this cost must be reduced to about $1,000-$10,000, a factor of 3 to 4 orders of magnitude. Space tourism has launch requirements similar to space settlement suggesting that a radical improvement in manufacturing technology may be necessary to enable space settlement.One candidate for a major improvement in manufacturing technology is molecular nanotechnology. An important branch of nanotechnology is concerned with developing diamonoid mechanosynthesis. This means building things out of diamond-like materials, placing each atom at a precise location (ignoring thermal motion). Diamond is 69 times stronger than titanium for the same weight and is much stiffer. If spacecraft were made of diamonoid materials rather than aluminum, they could be much lighter allowing more payload. For an excellent analysis applying nanotechnology to space development, seeMcKendree 1995
Diamond mechanosythesis may enable a radical transportation system that could allow millions of people to go to orbit each year -- an orbital tower. An orbital tower is a structure extending from the Earth's surface into orbit. To build an orbital tower, start construction at geosynchronous orbit. Extend the tower down towards Earth and upwards at the same rate. this keeps the center-of-mass at geosynchronous orbit so the tower stays over one point on the Earth's surface. Extend the tower all the way to the surface and attach it. then an elevator on the tower can move people and materials to and fromorbit at very low cost. There are many practical problems with orbital towers, but they may be feasible.
An orbital tower is in tension so it won't collapse, but it must be very strong or it will break. The point of greatest strain is at geosynchronous orbit, so an orbital tower must be thickest at that point. The ratio of the diameter of the tower between geosynchronous orbit and the ground is called the taper factor. For steel, the taper factor is greater than 10,000 making a steel orbital tower completely impractical. However, for diamonoid materials the taper factor is 21.9 with a safety factor the same as McKendree 1995 . Thus a diamonoid orbital tower 1 meter thick at the ground would be only 22 meters thick at geosynchronous orbit. Fullerene nanotechnology, using carbon nanotubes, may be even better than diamonoid allowing a smaller taper factor. Calculations suggest that the materials necessary for construction of such an orbital tower would require one asteroid with a radius between one and two kilometers. These calculations assume the tower is built from diamonoid material with a density of 4 g/cm^3 and the asteroid has a density of 1.8 g/cm^3 and is 3% carbon.
Thus, molecular nanotechnology may enable space settlement.
To the space settlement home page.
Author: Al Globus
I'm a thinker, dreamer, doer and a strong follower of stoicism. I have a passion to learn and apply that to make the world a better place.