Thirty years ago, Princeton Professor Gerard K. O'Neill published his scenario for space settlement.

"Is the surface of a planet the best place for an expanding technological civilization?"  O'Neill's question to his advanced physics students inspired a young generation of thinkers to examine the possibilities of space migration.  In the middle 1970s, the accomplishments of Apollo were fresh in our minds and the next steps forward seemed only paused but not yet abandoned.  We still dared to have great dreams, and great choices seemed to be opening up.

The results of Dr. O'Neill's initial classroom think tank were described in his Physics Today article in 1975.  His 1976 book The High Frontier explored the subject in more detail.  As others became enthusiastic about the idea, many articles appeared in magazines and newspapers around the world.

O'Neill never wanted the space settlement movement to be a one-man show, and he was happy to see a proliferation of books expanding on the idea.  Stuart Brand of Whole Earth Catalog fame published a book called Space Colonies, a thought-provoking anthology with ranges of opinion impossible to find in government and academic writings.  (A lightly censored version is archived at NASA's Space Settlement pages.)

In the mid-1970s I had occasion to ask one of the contributors, Paul Ehrlich, his opinion of the space colony idea.  He laughingly dismissed it, saying, "Maybe the Army Corps of Engineers will build it."   His skepticism was based on some of the early rhetoric that population problems could be addressed by space migration, an idea he rightfully dismissed on mathematical grounds alone.  A few years later he published (with Anne Ehrlich) Ecoscience: Population, Resources, Environment.   One chapter contained a discussion that showed a good deal of further thought about space colonies, especially the problem of creating stable ecosystems from scratch, even in such large volumes as O'Neillian habitats.

This remains a major challenge, and requires a body of knowledge we have scarcely begun to gather.  Just as the Human Genome Project is mapping out the intricate details of our genetic code, there will need to be the equivalent of a Gaia Genome Project to take inventory of the varied ecosystems across Earth, mapping out the interaction between the environment and its inhabitants.  It may be that certain soil bacteria, insects, and plants are critically important in as yet unknown ways.  When these subtle complexities are better understood, we can more intelligently design and build closed-cycle ecosystems in space.

Unfortunately, human expansion on Earth is in the act of displacing and erasing more and more pieces of the ecosystem. Those who would compile such a massive study of the Gaia system may soon be in the position of trying to copy the pages of a document that is burning and falling apart before their eyes. 

Time is of the essence in deciding if there will ever be a space settlement effort, on this and other critical fronts.

As the initial tide of space colony interest waned in the late 1970s, there was less talk of visionary ideas and more about economic justifications.  The main industry was seen as mass-production of solar power satellites, collecting energy in space and beaming it down to antenna farms for use on Earth.  When the second round of 1970s oil shortages hit at the end of the decade, the idea looked even more attractive.  But this was in the day when oil was rising from $15 a barrel to $37 by 1980.  By 1986, oil was down to $15 again, and the sense of urgency faded.  Today, with oil running over $50 a barrel and the supply a constant source of uncertainty, such a novel energy source could begin to look more inviting again.

Visions of space colonies and space power industries faded in the glare of some harsh realities: the Shuttle not living up to its selling points, the space station's protracted birth agonies, and the dwindling prospects for going beyond Earth orbit. 

If the ideas for space settlement have engineering validity, they deserve to be kept ready so they can be considered as an option when the times become right.  The English Channel Tunnel was an idea gathering dust on shelves since the days of Napoleon, long predicted never to happen, but suddenly the work was done and now the tunnel is taken for granted, as if it always existed.

It's time for a new generation to be made aware of the possibilities of space settlement.  One motivation that may be compelling--more than the Earth-saving energy production scenario, worthy as that is and even more than the thrill of just going out there--is the idea of living in a small but independent world of one's own choosing. 

There are now practically no new nations created on Earth without episodes of bloodshed.  Short of revolution and war, there are few options available for those who dream about establishing a new society somewhere, as various ideological and religious groups have historically done.  But even today, there are many people who would welcome the chance to settle a new frontier, where new ways of life could be tried.  If enough people believed there was an opportunity to leave whatever they didn't like about society behind and start over with a new nation aligned to their shared passions, I believe that could stir the pioneer spirit that still slumbers in many.  

Space settlement may really get started if the idea finds appeal in influential circles, especially among world leaders.  Several Great Themes have successfully circulated among leaders of the industrial societies, such as the need to avoid nuclear war, the importance of economic ties, and the need to make and honor international agreements. A Great Theme of establishing a permanent human presence in space--as a way to develop new energy sources to maintain high standards of living for the growing population of Earth, and as a way to back up Earth's living populations and preserve our collected knowledge, and to create new living spaces for those wanting new ways of life--would provide a guiding principle for vital policy decisions.

During the Kennedy era, when Project Apollo was presented, many influential people recalled the Colliers symposium articles and the Disney space television special.  The idea was already real to them, so they instinctively knew it could be done.  It was just a matter of priorities.

Having a technological civilization that's able to afford nice things like space travel depends on the infrastructure not being destroyed by wars or natural disaster.   The ability to "back up" our selves and our gathered knowledge may not always be possible as it is today.

As long as we live in a world where limited resources must be allocated among a growing population, we are ultimately doomed.  All our efforts to increase food production and extend individual longevity will end up trading a sooner catastrophe for a later one of greater scope.  So far, we are succeeding in a kind of pyramid scheme with Earth's resources, but in time the pressure of human numbers will strain and drain them. When resources become scarce and populations dense, individual freedoms are unaffordable luxuries.

If civilization is to be allowed to spread beyond Earth, it must take place before the world's resources are forcibly redistributed or squandered and disrupted by major wars.  In recent history, we have seen we have seen our ability to reach the Moon thrown away to pay for a massive military effort that only managed to delay the communist takeover of South Vietnam by 10 years.

We have lost precious decades of establishing a beachhead in space due to wavering priorities and economic downturns.  We cannot assume conditions will always be as right as they are now for such bold ventures as space travel.  Instabilities tug at the house of cards that we call civilization.  We still have time to accomplish the miracles we know are possible to achieve, but we need to begin the work while we can still afford to do it.

Don Davis (donaldedavis.com) is the artist most responsible for making space colonies look like a good place to live.  He won an Emmy for his work on Carl Sagan's TV series Cosmos.  Today he is the leading astronomical artist for full-dome theater shows in planetariums worldwide.

NOTE: The views of this article are the author's and do not reflect the policies of the National Space Society.

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