Newsgroups: sci.space.policy,sci.energy,sci.environment,rec.arts.sf.science From: burns@latcs2.lat.oz.au (Jonathan Burns) Subject: _The Millennial Project_ Review (1/5) X-Nntp-Posting-Host: latcs2.lat.oz.au Organization: Comp Sci, La Trobe Uni, Australia Date: Fri, 24 Mar 1995 00:36:18 GMT --------------------------------------------------------------------- (C) Jonathan Burns burns@latcs1.lat.oz.au January-March 1995 The material below is Copyright; it may be copied freely, on condition that this notice appears together with it. ---------------------------------------------------------------------- The Millennial Project: Colonizing the Galaxy in Eight Easy Steps Marshall T. Savage Little, Brown and Company 1994 ISBN 0-316-77165-1 (hc) ISBN 0-316-77163-5 (hc) Review for interested newsgroups -------------------------------- 1. Introduction --------------- This book proposes the colonization of space in stages, beginning with a terrestrial marine colony project. It focusses on specific technologies; none of them new, but some of them less well discussed. The exposition binds them together, to give a convincing appearance of coherence and practicality. As well as a discussion, the book is an invitation to participate in an actual effort founded by the author, apparently in the stage of organization and early negotiation for resources. _The Millennial Project_ is 508 pages, nicely produced in trade- paperback format with diagrams, appendices, index, and a 20 page bibliography. A centre section contains 16 plates of artist's- conception paintings. Many quantities are given, a high fraction quoted from references. There is a brief introduction by Arthur C. Clarke. Several things set the book apart from the average. Compared with other discussions, e.g. T.A.Heppenheimer's _Colonies in Space_, which explore possibilities, the author's stance is boldly self- committal. He himself is establishing his Foundation, right now: do you want to join him? Throughout, Savage shifts between abstract discussion and the point of view of a cadre of colonists who have devoted their lives to space access. The attitude is not one of taking advantage of commercial and scientific demands to get a few people out there; instead, the colonists are to establish one multi-billion-dollar enterprise after another in order to open up the huge settlements they envisage. Rather than riding an economic wave, they are making one up as they go. The valiant stance is backed up by an accumulation of aesthetic novelty, in the scope and openness of the habitats. Like the changes in visualization from the early spaceship-as-U-boat, to the grand tori of _2001_, to the O'Neill colony vistas, each step in technology paints its picture of human opportunity on a larger canvas. Meanwhile the stream of quantitative argument suspends disbelief. The total effect is intoxicating. Disbelief might be suspended until the second or third reading. 2. Synopsis ----------- The eight easy steps have a chapter each, starting with step 2. In order: 2. Aquarius: Self-sufficient marine colonies. 3. Bifrost: Maglev and laser-launch space access. 4. Asgard: Biologically self-sufficient bubble-type space habitats. 5. Avallon: Nation-sized lunar colonies in domed craters. 6. Elysium: Terraforming of Mars. 7. Solaria: Occupation of the Solar System. 8. Galactia: Open-ended propagation at 0.1 c. 1. Foundation: Organization necessary to begin the above. Necessarily, the scenario becomes vaguer in the final stages, but Savage keeps up the excitement to the end, arguing the evolutionary scope of Dyson-scale human populations, and the desert nature of the cosmos. It is in 2-4 that the space vision is reworked. The Foundation chapter needs separate discussion. The first chapter lays out the design for a floating city-sized colony, moored to the continental shelf in the Caribbean, based on ocean thermal gradient energy conversion (OTEC) generators, and the consequent upwelling of nitrates from below 3000 feet depth to support large growths of algae. The Aquarius colony in full flower, is self-sustaining in food, water, power, and building material, and hosts sea-based industries. It is highly profitable, due to industry in algal protein, mariculture and secondary production, export of fresh water and energy, and to its having an internal monopoly of life's necessities. It is nearly self-reproducing, in the sense that the colony can build another colony from marine resources. An Aquarius colony is not environmentally neutral, but its net effect is limited to its immediate area, and is arguably beneficial. (With a population around 100,000 apiece, such colonies would not provide much more human living space; but in providing water and massive quantities of protein, they would permit land use to be modified in eco-friendly ways.) With a thousand colonies or so in operation, the tensions of the next doubling in world population become more negotiable. Starvation is unthinkable; electrical and fuel energy based on solar heating of the oceans is abundant. While this new ecological component expands, it is also making high profits, which are invested in the next stage. A period of a generation or so is necessary for R&D to proceed through construction of the Bifrost launcher to the first Asgard colony. A 125 mile tunnel is bored under the Serengeti Plain, and up the slope of Kilimanjaro. A magnetic accelerator is installed, for passenger or cargo capsules of 14 tonnes, and evacuated. A capsule may be accelerated to 5-6 km/s. A laser-launch system at the exit provides the boost to 8-9 km/s orbital speed. The capsules are delta-winged vehicles designed to withstand hypersonic shockwaves and re-entry. The road to space is now open. The initial cohort of engineers sets up a construction shack, and proceeds with the construction of the first Asgard colony. Both lunar and asteroid resources must be tapped to some degree, at an early stage. Asgard comprises a double silicone bubble with 2 metres of water between the layers. It contains 13 smaller bubbles in cuboctohedral packing, each in turn containing 13 bubbles of apartment size, about 6.5 m radius, 1100 m^3 volume. (The arrangement can be nested outward to awesome scale). There is no gravity. The atmosphere is pure O2 at 3 psi. Food is entirely algae-derived, using techniques developed in Aquarius; waste is totally oxidized in supercritical water oxidation furnaces. Power is provided by solar-powered steam turbines in half-silvered bubbles. The first Asgard cluster is set up in Clarke orbit. With viability established, the next step is to exploit the communications advantage of large directional antennas, capturing a global cellular-phone market. After a period of perfecting the stability of the colonies, the Moon and asteroids can be exploited for resources, and the age of true space colonization begins. In the following chapters, majestic vistas unfold, with speculations which have been canvassed in many other books. The treatment most resembles George Zebrowski's discursive SF novel _Macrolife_ [Ref.2], especially in the theme of habitats containing the means of self-reproduction, and recapitulating the change from single-cell life to much larger organisms with unprecedented powers. I will not discuss these chapters further. 3. Discussion ------------- 3.1 Aquarius: OTEC Progress and Costs ------------------------------------- (Thanks to Teresa Hamilton of the First Millennial Foundation for providing additional information in issues of the half-yearly newsletter, _First Foundation News!_.) OTEC has been a modest runner in the renewable-energy stakes since at least the mid-'70s: less has been heard about it than most, probably because the scale is too large for small bands of enthusiasts. (OTEC was characteristic of what I would like to call the High Appropriate wave of technological optimism, which ran from the mid-'60s into the '70s, and disappeared with the end of the "Oil Crisis" and the entrenchment of a world recession. The period was notable for concepts of ambitious scale: giant wind towers and solar collector fields, sea-current turbines, evacuated maglev rail-tunnels, arcology cities, fuel crops and more. The United States' ERDA deserves credit for much of the research on unconventional concepts; but it has been accepted in later years that progress would be piecemeal, and grand designs were left for the next century. Savage is not so timid, though...) Savage lists 18 direct references on OTEC, mainly papers for U.S. ERDA and the Ocean Energy Conference series. The state of the art is represented by these (from the FFN newsletter): National Energy Laboratory of Hawaii Authority (NELHA): A 210 KW open-cycle OTEC is in operation (appears from diagram to produce 187 KW net electrical). (FFN, June 1994) GenOtec has designed a 5 MW shore-based closed-cycle OTEC, for a proposed resort on St Croix, U.S. Virgin Islands, to cost $32 miliion. "If the resort gets its venture-capital funding, GenOtec will most likely get theirs." (FFN, Dec. 1994) "Sea Solar Power is in final design phase of floating OTEC for delivery to India." This is supposed to be a full 100 MW (net electrical) plant, installed in a 25,000 ton ship. Cost: $250 million. (FFN, Dec. 1993. A more detailed decription was promised for the following issue, but has not appeared.) I am not sure what to conclude from this. It may be that NELHA is limited by funding, but at least they are bending metal. The GenOtec figure sounds plausible, but it sits awkwardly with the article on NELHA, in which Savage states: "A barrier to the successful commercialization of closed-cycle OTEC is the cost of fabricating and deploying the cold water pipe... As soon as a flexible pipe system is developed, closed cycle OTEC will be ready for market." My guess is that a 100 MW plant is nowhere close to being built, and that research to that point will be more costly than Sea Solar Power's estimate of $100 million. As a final point, from an article by Phil Kopitske in FFN, "... the technology challenge of OTEC is to get the capital cost of the plant down to $2 million per MW where it can compete with coal plants. Luckily, small OTECs can make more money selling fresh water and air-conditioning chill water than they can on electricity, which makes small plants economically viable." Note the quoted cost of GenOtec's plant is $6.4 million per MW. (FFN Dec. 1994) And this, I think, spotlights the equivocal nature of OTEC at present. It's a synergy: power and water from one source: appropriate for an island without either utility. But the synergy can be devalued piece by piece, if either benefit can be more cheaply supplied, e.g. by imported natural gas. But if OTEC can be shown to work at the 100 MW scale, it is also appropriate, say, for a tropical coastal city with a rising population, an aging power utility, and a fresh water supply increasingly required for agriculture and salinated downstream. A combination we will surely see more often. Sea Solar Power is proposing an appropriate solution for India, at least. And if the solution could be proven for $100 million, that would be a bargain. 3.2 Aquarius: Preliminary Steps ------------------------------- Aquarius is to be a floating city, with a capital cost of $ 8 billion at current prices. Nobody solicits credit like that on the first try; so Savage's proposal for the initial core group of the Foundation is to start a popular magazine on the lines of _Omni_, which will explore all these concepts while making some money. This will support an experimental colony in the Caribbean, something of an expeditionary camp, in which a social structure can be shaken down, and the members can get a feel for how much they can live without. I imagine something like the Iron Age project in Britain, an archaeologists' attempt to mock up the living conditions of pre-Roman times. Some cash flow will come from visitors. On the basis of this experience, a more ambitious settlement is proposed: a resort in the Seychelles, OTEC-powered, with gardens planted on one of the coral reefs. The algal-bloom from deep-water nitrates concept will get its first real trial; a worthwhile experiment, since the steps from algae to usable soil on a major scale are unclear as yet. A sufficiently determined group of people should have a fair chance of making this work. Whether they can turn it into a $100 million per annum business is another question. Note that an OTEC-supported resort is already being considered for St Croix, and may (it is hinted in FFN) be willing to take on the Foundation as partners even at this stage. Also that the Foundation would be in on the ground floor of an industry with $100 M p.a. potential, per installation, if it proves out on the basis of present high-risk trials. There should be plenty on money to be made from adding value to real estate, whether barren atolls with no fresh water reserves, or island communities with existing tourist industries. Let us assume the Foundation are successful, and finally fund their first Aquarius cluster as planned, in international waters some 200 miles off the coast of equatorial Africa... 3.3 Aquarius: Algae-based farming --------------------------------- Aquarius' critical resource will be the artifical upwelling of nitrates. Mariculture products account for over 75% of the estimated mature revenue stream of $ 8 billion per year. Savage makes much of _spirulina_, an algae which will make very efficient use of the nitrates. In principle, it makes a terrific human foodstuff: wholly digestible, 65% protein by weight, loaded with beta-carotene, but also chlorophyll. You can buy this in health-food shops: it is bright green, and is reported to me as tasting vile, unless the pigments are removed. Beta-carotene is highly valuable in itself. A critical assumption is that natural regions with high fish production result from nutrient upwelling and algal increase; and that articial upwellings will likewise become rich in marine life. There is also the phosphorus question. Savage claims that nitrates are the critical limitation on algal growth, but from his tables, spirulina looks to be about 30% phosphorus by weight. The mariculture prospects will be illusory if there is not enough in solution at depth. (To make matters more confusing, recent experiments in Antarctic waters seem to have confirmed that iron is the critical nutrient for much of the microscopic food chain.) A more delicate assumption is that one particular algal species, spirulina, can be multiplied to the exclusion of others. We are familiar with toxic blooms at sea and inland waterways, resulting from phosphorus and other nutrients in domestic and agricultural runoff. There is also the danger of stirring up sediment in quantity from the seafloor. Marine biology to the present may be able to predict adverse algal responses; my guess is that the science is not yet that firm, and that a deep-water 100 MW OTEC would pay for itself in pure research in the long run. It also seems that a thorough program to investigate marine food chains would be a necessary precondition to implementing Aquarius on a continental scale: because one cannot tell what possibly critical link in a chain might be poisoned by radically larger algal densities. (Human sewage streams already constitute informal experiments in this area.) Mariculture is only a moderately large industry at present, although it provides some countries with up to half their fish. Shortage of exploitable coastline seems to be the reason. Aquarius would be a real innovation in the field. Savage foresees areas on the km^2 scale, devoted to salmon, oysters, lobster and other high-value sealife. Seaweed is to be cultivated as well, for the silk-like protein algin. Genetic engineering of algae to produce proteins to order, is another capability of Aquarius' mariculturists. This is a natural idea; but I believe it would be barred by existing world agreements. The analogy is the Green Revolution. Originally, this was a matter of selective breeding and interbreeding from world- wide varieties, to produce grains with superior yield, blight resistance, etc. Only recently have true transgenic varieties been tested, having genes from very different species. In these trials, the watchword is that a new variety must be unable to transfer the new genes to a wild kindred species; a condition surely impossible to meet with algae. For the sake of argument, imagine an algae which turns out to produce botulinus toxin, or the "red tide" palytoxin. Perhaps these are easily avoided; but any new variety acting adversely on marine food chains would be bad enough. This is a pity, because providing an industrial-scale resource for a Third-Stage Green Revolution would be a major world contribution for Aquarius. Savage expects mariculture would provide $ 6.2 billion p.a. of a total $ 8 billion gross revenue. Tourism is to bring in another $ 1 billion; services, mainly in information technology, $ 450 million. Hydrogen, magnesium, etc are minor additions. One more major technology is proposed for Aquarius: formation of light concrete sheets for its construction, made by depositing dissolved calcium and magnesium carbonates electrolytically on steel or magnesium mesh. The references to this are mainly due to one Wolf Hibertz, who has a number of articles and patents between 1979-1984. An elegant concept; I can only guess that it has not been used because of electricity costs. I remember mention some years ago of a scheme to build artificial reefs in this way, disposing of scrap steel. 3.4 Aquarius as contributor to global resources ----------------------------------------------- Early in the book, Savage argues that Aquarius will open up technologies which will help keep the world from a population and resources crisis in the coming century. 1) Food. A mature Aquarius, according to Savage's figures, can produce 320 tonnes per day of spirulina powder, with the carotene and chlorophyll removed. One-tenth of a pound of this, added to a pound of flour, will provide the daily protein requirement for an adult. Thus the daily production would upgrade carbohydrates to sustain 320 * 2240 * 10 = 7.2 million people, if need be. A thousand Aquarius clusters would feed the human race. This is at odds with economics, at least currently. As I write, the Australian Commonwealth government is at odds with the Clinton administration, for continuing to sell skim milk to the Philipines, having assured us that our market there would not be compromised. Worldwide agriculture would be in chaos if the world suddenly turned to algae-fortified cornflakes for its staple. Still, the assurance of sustainability is welcome; and spirulina powder stores well. The 7.2 million figure really spells out the inefficiency of our diets, especially the animal parts and products. Probably, cheap spirulina would show up as an animal-feed supplement. Any advance which reduces the need for grazing land, makes more arable land available; and anything which reduces the need for arable land, makes more available for other uses - habitation, recreation, topsoil regeneration, reafforestation, etc. Algae- farming should count as an extra degree of freedom in the resources-environment equation. 2) Fresh water. The OTEC open-cycle process produces fresh water by evaporation at low pressure. Savage estimates the fresh water production of Aquarius as 175 million gallons per day. (In the newsletters, he has shifted allegiance to the closed-cycle process, which also produces fresh water by condensation.) Fresh water from the continental shelf would allow equatorial cities to grow and remain healthy, despite agricultural demands on river water. It may be that better management of water would be cheaper than supply; but storage from the monsoon season through the dry requires large dams. Also, if fresh water could be pumped inland, it would take pressure off the river systems, bringing them back toward a natural state of affairs. It seems to me that river systems are such a critical ecological component, that the ability to keep them serving their natural functions would be worth very large amounts of money in the next couple of generations. In an attempt to verify these thoughts for the Australian context, I looked up the CSIRO report, _Greenhouse: Planning for Climate Change_. Our prospect for the next 30 years is apparently: increased rainfall in the tropics, erratic or lessened rainfall in the temperate south; more frequent storms and higher winds; and more topsoil loss in the southern wheat-growing areas. Almost every adverse effect in this is due to excessive land clearance. Reafforestation, not water shortage, is our problem. (We have major arid regions, true. But it is not just a matter of adding water. Those regions do not drain to the sea. Add water, and the underground salts rise, resulting in saline bogs.) Having an Aquarius-sized OTEC system offshore would seem to be like having your own little cloud, permanently on tap. For tropical nations with long coastlines, e.g. Indonesia, the technology might be a real boon. 3) Power. Aquarius is in a position to export 300 megawatts, as electricity or as hydrogen. At 2 KW per capita, this would meet the needs of 150,000 people. As mentioned above, an OTEC scheme for present-day implementation estimates the cost as $ 6.4 million per megawatt, where coal is $ 2 million. However, Savage estimates that the mature Aquarius would be able to generate power for $ 1.5 million. If workable, this puts OTEC on the list of power generation technologies available to city and province size utilities. The energy source is very diffuse, but seafloor is a little- used resource. A specialized power plant could use the area at the same time for wind, solar or wave generation. Savage writes as if he sees OTEC as a comprehensive solution to the world's power needs. As an order-of-magnitude estimate though, 10 billion people * 2 KW = 20 million megawatts, or the output of 66,666 Aquarii. 4) Carbon sequestration. That CSIRO report models (n.b does not predict) that global warming will cause a rise in sea-level of 1 metre over 30 years, due to thermal expansion. Then there are the weather changes, and as Savage points out, the danger of water vapour, a greenhouse gas, increasing to the point of positive feedback. This is largely beyond calculation at present. However, suppose the worst... Savage reckons that an Aquarius colony could harvest 600,000 tonnes of carbon per year as algae, and sink it to the seabed. "With 10,000 marine colonies in operation, a billion tons of CO2 could be removed from the atmosphere each year. This, together with the reductions resulting from replacing fossil fuels, could halt and even reverse the build up of carbon dioxide." 3.5 Aquarius: environmental hazards ----------------------------------- Although Savage's model is benign compared to land-based ways of achieving the same goals, it would have a potential for danger if used on the supposedly world-saving (10,000 colony) scale. OTEC plants continually bring up water from below 3000 metres. If this depth is near the seabed, sediments will come up too, with a general increase in turbidity. More seriously, the colonies are supposed to add 800,000 tonnes of biomass to the world per year, including nitrogen and phosphorus which will continue to feed algae as they are recycled through plankton, fish, humans, etc. The possibility should be watched, that blooms of inimical wild algae will result. I have no specific knowledge here, but I note that diebacks on the Great Barrier Reef are being attributed to turbidity and over-nutriation, caused by farm water runoff along the coast. This is no reason not to proceed with Aquarius. Rather, the opportunities to research algal growth, useful and inimical, and the effects of seafloor agitation, are benefits which the colony could sell. Another thing to watch will be the effects on higher sea creatures of Aquarius colonies with their pipes, pumps, mooring lines, membranes, etc. The analogy is driftnet tuna fishing, snaring dolphins, turtles, etc. We still have little solid data on the effects of the noisier modern ocean on hearing-guided animals; how noisy is an OTEC? This is to say that some adverse effect might keep these marine cities from expanding to world scale. But one might say the same about agriculture. Aquarius would give the world more options; let the world sort out the least or least costly of evils. 3.6 Aquarius: Profitability --------------------------- One problem in evaluating a synergy is, that the proponents can keep shifting the ground. You say, "We can do this part cheaper"; and they reply, "But there are all the other benefits; and since we can re-use the infrastructure, we're still ahead." Demolition of the total scheme has to be in detail and cumulative. Aquarius is a synergy. If you invest in the OTEC for power, you get the nutrients and the water-condensers as well, so why not exploit them? And so on round the circle. Consider the alternatives. There are competitors to ship coal, and uranium, worldwide. Fresh water can be managed far better than it is, by the relatively cheap means of planting catchments, building reservoirs, and investing in modern sewage treatment and water-recycling plant. Agriculture is so productive that the question is now competition for markets. If suppliers in each of these areas were asked to judge their optimum single-use technology versus Aquarius, each one would find the single-use technology cheaper - even though the total cost of the several decisions were substantially greater than Aquarius. I note that the proposed GenOtec startup on St Croix is playing the water card, for air-conditioning and ice, because it is not the cheapest electricity solution. If St Croix were not an island, no deal. But there is a good reason to foresee the OTEC synergy being adopted. Equatorial countries with extensive coastlines count for many of those in which population is rising rapidly, with tens of millions of births per year between them. Towns are becoming cities, and cities "megacities". These countries are floundering in virtual debt-peonage, largely because of the necessity to provide utilities and industrial infrastructure for the younger generation. Their situation is urgent, and they are responding by concerted programs of modernization. This means that their multi-year decisions on water, power, roads, communications, housing, etc, tend to overlap, rather than be initiated several years apart under separate administration. Under these circumstances, a unitary solution to various needs stands a better chance of appraisal. It could look good as an investment. A solution whose plant is largely offshore, and need not involve the disruption of existing habitation and production, could look even better. This is to say, that if Aquarius can be made to work at a modest profit (forgetting the billion-dollar space project), over a period of say 10 years, it might catch on spectacularly. The mariculture aspect alone is one that any city will turn into a market with thousands of jobs. Aquarius' main problem might be fielding enough staffpower to franchise their technological expertise; which is all they would really have to offer, since all components of Aquarius (saving some important patents) are in the public domain. Anyone could have done the OTEC thing, years ago. It's just that the World Bank (and who can blame them) likes to lend money for proven, off-the-shelf solutions, but not for wild-eyed High Appropriate experiments. The game is other than Savage would have it, I think. If Aquarius worked, in the form he pictures, it would not be left to enjoy a monopoly for long. The larger synergy would indeed be dismantled, and reassembled by parties content to run it at lower profit margins; as public utilities, or as a basis for say, oil drilling. Any competitor could flood the world with magnesium or beta-carotene, and leave Aquarius with 370 tonnes per day of expensive cattle-feed. But, Aquarius doesn't need a monopoly; any more than Westinghouse needs a monopoly on nuclear power plants. What each needs is a proven ability to install the technology, on time, on cost, and with sensitivity to local conditions. Inasfar as there are only a few companies working on OTEC at present, the original Aquarians have a fair chance to become, and remain, the best in the business. Given that, additional opportunities will arise. For instance, the Aquarians will necessarily become superlative marine engineers in general, or go bankrupt. They will need to understand things like corrosion, wave properties, algal fouling, plumbing, and so way on. There will be patents in every problem. Assume it so; and assume the competition. Will Aquarius make enough to run their own space project? I have no answer, so I'll answer a more modest one. Yes, the opportunities in implementing the Aquarian system are (either completely illusory or) sufficient to allow them also to break into radically different technologies, including tunnel construction, maglev transportation, and high-power electron beams. 3.7 Bifrost Technologies ------------------------ The goal is a 125-km evacuated tunnel containing a 10-g magnetic levitation and accelerator track; rising to 5000-6000 metres above sea-level, where the vehicles exit to atmosphere at 5 km/s. A battery of 6 free-electron lasers then accelerates a vehicle by explosively evaporating water propellant contained in it, increasing its speed to 8-10 km/s, sufficient for orbit. In the book there is one of those photos, of a vapour-wreathed superconducting disc, a few ounces weight, floating over a group of magnets. Now visualize a superconducting assembly supporting 150 tons, including its own weight; and the homopolar generator needed to generate the field. Now visualize an 80-mile tunnel lined with such generators every few metres. That is the electromagnetic transport component of Bifrost. In the final second, the vehicle covers 5 kilometres; the generators are being activated that fast. In this phase, kinetic energy is being delivered to the vehice at 4 gigawatts. Coilguns have accelerated small payloads to several kilometers per second. At another extreme, maglev railways are practical for trains around the mass of the Bifrost vehicle, travelling at 200-400 kilometers per hour. Bifrost would be the world's largest coilgun, delivering 1000 times the power of a maglev railway. The energy requirement is estimated as 60,000 kilowatt-hours. The energy is to be supplied from an Aquarius module (300 megawatt capacity), and stored in six superconducting magnetic energy storage (SEMS) rings. (Savage calls these "capacitors", which may mislead some readers.) For comparison, some figures from the leading article in _IEEE Plasma Science_, Oct. 1994. In this issue, a variety of high- power microwave generators are showcased, laboratory models ranging from kilowatts to megawatts output. But the expectation is that they can be scaled to 100 megawatts apiece, and will meet the requirements of the planned 0.5-1 Tev electron-positron linear collider, which will deliver a short burst of power peaking at several terawatts. Among the generators are free- electron laser designs for microwave frequencies. From an article in _IEEE Spectrum_, 1994, an experimental SEMS system with 1 gigawatt peak discharge is in the planning stage. Homopolar generators are a proven way to generate high currents for short periods, having been used in particle accelerators for at least 40 years. This suggests that Bifrost might not be the largest or most powerful electrical machine of its time. By the time Aquarius could reach its mature earning potential, the Bifrost technology might be an engineering project with few unknown factors. Savage's position, consistent with the rest of the book, is "We will build it"; as a pure investment in space colonization. Aquarius' profitability is supposed to be sufficient, at $ 4-5 billion per year. This is about one-third of the NASA budget. The Bifrost lasers are to deliver 250 megawatts each. Today's performance is approaching 10 megawatts (continuous wave). This contrasts with a few kilowatts for gas lasers of the late '60s. The limits of free-electron laser technology are hard to predict. Savage quotes Aviation & Space Week, for a report of 40% efficiency, and another suggesting that most of the remaining 60% of power can be recovered. As noted above, microwave FELs with 100 megawatt output are currently being proposed. The other major component of Bifrost is the launch vehicle. This dart-shaped craft has to negotiate the multi-gigawatt driving field; the shockwave on entry to the atmosphere at 5-6 km altitude; the laser evaporation of the ice propellant at 900 atmospheres and 10,000 degrees C; and re-entry. In all, the Bifrost project appears to require believable advances in technology already demonstrated. The scale is that of a major aerospace weapons or launch system, or of a major particle accelerator project: say Apollo, or the B-2 bomber, or the Superconducting Supercollider. Savage gives a costing of $ 25 billion. 3.8 Bifrost: Financial Basis ---------------------------- How plausible is it, that a "nation" of a few million could come to dispose of so much money, and of such technological expertise? The answer depends on timing, and on how successful the Aquarius experience has proven in establishing a distinct society. At each step so far, the founding colonists have been faced with challenges. There are easier ways to make a living, after all. Whatever the differences among the Aquarians, they have it in common that the only reason they are going through with this is to get somebody into space - themselves, their children, a later generation. Success breeds success, in terms of credibility, recruitment and alliances. If the Foundation can make a success of the resort business, and their first major OTEC works, their credit will be good for similar projects. It may take a few contracts, but if they can stay on track, they can afford to build the first OTEC module for Aquarius; and so on. Mariculture will be a business before Aquarius construction begins; the electrolytic magnesium production and CaCO3 deposition techniques will have been tried in small, and scaled-down floating structures built. The finance can be developed in stages, as the city rises over 7-10 years. With Aquarius up, the revenue may take the form Savage envisages, or not. The marine-engineering techniques will be ready for exploitation, and the sea-farming can be expanded to what the market will bear. Plausible enough, so far. So let's allow that $ 4-5 billion per year... We have a mini-nation, 100,000 strong, not counting expatriate supporters, where the Big Science tail wags the National dog. The general idea of a modern country is one in which most of the population are absorbed in earning the necessities of life, which also earns them the choice of additional goods and services. Work and leisure occupies much of their time. Education is a classification system, which most people do not turn directly toward any vocation. Despite the technical excellence supporting the consumer products, a modern country need not be intensely technophilic. Research and development make up a small part of corporate and government budgets. Savage would have Aquarius spending 50-60% of the gross domestic product on research. Aquarius directly supports 100,000 citizens in food, housing, clothing, transport and information. Once the colony is constructed, how many are required for maintenance, farming, merchandising, hospitality, medicine, social services? Education is up-to-date, and technically oriented to a high degree. It is really quite a narrow society, rather like an army. Its goals are clear. It gets things done. If you don't like it, you can leave. As Savage says, it is a large company store, with little consumer choice. However, by virtue of that simplification of life, there are few laws, and government, an ad hoc electronic democracy, can be municipal in scale. Just how Aquarius conducts trade, and how it recruits, are not much considered in the book. There will be legal questions in various countries concerning the taxation status of activities carried out by their citizens while "abroad". Aquarius will be located beyond the 200-mile limit; but will it choose to benefit by franchising the technology for coastal operations? Above all, how will it develop the high-tech expertise for the Bifrost stage, stuck out in mid-ocean? 3.9 Aquarius to Bifrost: Economic Alliances ------------------------------------------- (Here my opinion goes into areas that the book does not. I don't think it actually contradicts Savage philosophically, but it may not be what he has in mind.) As I suggested above, the Aquarius concept is a natural partner for coastal cities needing power and water. The colonists should therefore not be shy about making alliances with equatorial governments; of whom, to some degree, they can take their pick. Given a sea-grown installation which supplies power and water to a city, the obvious next step is to bore the conduits. This would give the marine engineers a necessary initiation in tunnelling machinery, and a new product line. Tunnelling can be developed in the same gradual way as electrolytic sea-construction: start small, make a profitable thing of it, consolidate experience, then lay down your money for the big one. London and New York, to take two examples, are coastal cities which once benefited from cheap labour, to build underground railways. For some time, these carried a fairly high percentage of the commuters, and it still causes disruption when they are closed down. Third-world cities are growing rather too fast to benefit in the same way. It is easier to lay roads. Electric transport is more expensive, but in the long run more economical in land-use, as well as hedging against oil price rises. Here then is a way for the Aquarians to gain experience in their next two technological specialties, tunnelling and maglev, singly or in combination as the customer would have it. It is true that maglev is a relatively expensive kind of railway system, and more suited to high speed than short haul. But there is the basis for a genuine partnership, with employment for local labour, and a market for electric power, and possibly magnesium or aluminium. Aquarius has a potential advantage as an investor: it can wait for its profits, spacing the returns on investments out along the curve of its financial requirements over ten or twenty years if necessary. Being based on the Equator, it has an interest in local currencies, which can buy labour in its region. It is equally important to gain political allies, and social involvement at many levels of the societies with which the colonists must deal. Savage's book implies a somewhat aloof, "We are but guests upon the Earth" attitude on their behalf; this is part of an ideology of complete self-sufficiency, motivating import-replacement at every step. It is valid, in fact I think it is vital. But so is the acceptance and testing of political interdependence. The Project dare not lose the Equator. Therefore they must not be seen as aliens, or as a soft touch, against whom the Equator can be held hostage. If on the contrary, they can get themselves seen as partners, and disseminators of high technology in "the South", then the eventual prospect of Quito or Kilimanjaro as the road to space will be more negotiable by far. Nor should the potential for recruitment be overlooked. 3.10 Research Alliances ----------------------- The one thing the Foundation absolutely cannot get on without, at this stage, is brains: the one-in-100,000 kind who can push gyrotrons to the limit, extract valid aerodynamic data from shock-tube trials, or get down among electron orbitals to determine what makes superconduction work. It is possible that in the process of raising Aquarius, the Foundation will have recruited the research force necessary. If not, a surplus of $ 5 billion per year would still allow them to operate more or less as NASA does. They could endow scholarships, let out contracts, host conferences, and maintain a network and library resource; up to the point at which they could confidently lay out the money for the 10-year Bifrost construction effort. They could grow their own garden of externally developed patents, funded on the sole condition that the Foundation be able to exploit them for their leap into orbit. There would be opportunities for further cooperation with the Equatorial states, which I proposed above would be natural customers for the Aquarius technology, paying by stages in their own currencies; i.e. principally in their own peoples' labour. The economic situations of these countries - I am thinking of Indonesia, India, Mexico, Kenya - are various, and volatile. Generalizations should not be taken too far. But generally, these economies are growing; they are hospitable to foreign investment, in agriculture, manufacture and tourism, but not so much in local high-tech innovation. They include a rapidly increasing population of youngsters, for whom it is difficult to provide stability, more so schooling, and still more so real economic opportunity. In doing their best to provide infrastructure and up-to-date capital equipment, these states have borrowed so heavily, that significant fractions of the domestic product are committed to repayments; and especially in the smaller ones, this has come to the point that they are allowed further credit only on condition of virtual dictation of economic policy by their creditors, the IMF or the World Bank. Now consider Aquarius. As a simultaneous solution to several urgent utility needs, an offshore OTEC platform offers a lot of bang for the buck. The full Aquarius package as Savage estimates it, is $ 8 billion, but this is for a complete self-sustaining model city. The essential structure appears on Savage's figures to be more like $ 2-3 billion, of which $ 1.2 billion is for the OTECs themselves. The Foundation might be able to offer a deal on the order of: $ 1.5 billion up front, in borrowed foreign currencies, paying for the OTEC and other components which are cheaper for the Foundation to buy than to manufacture; plus $ 1.5 billion payable over ten years, of which $ 1 billion is in the home currency. With this, the Foundation can buy factory structure and services, as well as things like metals; and the services of local engineers and factory workers. After working a few such deals, the Foundation can get what it really wants, which is a world-class production system for high-power electromagnetic and aerospace components. The allied countries get an engineering elite, owning significant patents of their own, who can attract new investments in export opportunities. It is really a matter of focussing talent already present and partially employed, putting economic demand on universities and so on, in a way that the more usual investments in semi-skilled labour do not. I recognize that this goes against Savage's principle of maximal independence, from financial entanglement and from government regulation. I suggest it because it appears to serve the interests of both sides, because it makes the most use of resources which Aquarius can generate (from the sea and from its peoples' experience), because it gains the Foundation much of the Bifrost structure relatively cheaply; because it would somewhat further the cause of economic equality between the North and South ... and because it might save the Foundation from putting all its political eggs in one basket. 3.11 Bifrost: Political Dangers ------------------------------- Some irony may be seen in my posting this section. Savage's appeal is going primarily to Americans, and if the Foundation gets going the nucleus of pioneers will be mainly American. Their patriotism is not to be doubted; and yet years of discussion in the Internet space groups shows ingrained dissatisfaction in Americans with their government's space policies, and considerable distrust for government in itself. Savage postulates a clean start for the Foundation, asking nothing from any government. The first-stage colonies will have their own constitutions, and the colonists will work out their own social arrangements, taking advantage of electronic communications: the first net government, or anarchy or whatever. In the Aquarius phase, this seems likely to meet with only minor resistance from the USA. There may be some quarrels over taxation, citizenship, voting in state and national elections. But Aquarius itself is an innocuous project, in international waters; and if the colonists were to deal with other governments, it would be no more than any trading corporation. With Bifrost however, the Foundation will be seeking pre-eminence in several of what the USA has to regard as strategic technologies: aerospace, advanced materials, communications, high-power microwave and lasers. At some point, America's military planners will notice that the Foundation means what it says; roughly, at the same time it is generally realized that the magnetic-launch idea is practical. Given that homopolar generators, SMES, and 100 MW microwave emitters are practical right now, and being scaled up, it may be that the next few feasibility studies on coil-gun propulsion will declare a launch system achievable in short order. Conceivably, the USA could be inspired to bypass Aquarius and lay out tens of billions for a launch system based on Hawaii or Cape York, Australia. Or then, perhaps not. But if not, how will they regard these upstarts scooping militarily and economically critical technologies, while declaring themselves immune to the security and safety strictures of the American research labs? (Especially when the upstarts are talking about building gigawatt lasers in orbit, and ablatively nudging space debris to re-rentry!) By implication, Savage is saying that the Foundation will take on the responsibility for ensuring that orbital technology is never misused, e.g. for microwaving comsats into oblivion. Where are the Ballistic Missile Defense Organization's Brilliant Pebbles then? Would the Foundation accept them as cargo, for example? Sooner or later, the matter must be made subject to international law. The question is, will the Foundation have taken care that it has a say in nominating the umpire? Purity of motive might gain the Foundation credibility in some trading negotiations: the fact of being committed to the long haul would keep them honest in the short run. But that wouldn't save them in an argument over aerospace security with the American defense establishment. The easiest measure against the Foundation is restriction of their access to American research. For instance, there was that tedious period ten years ago, when personal computers were declared strategically important, and Australian companies were having to fill out COCOM forms before they could import Apple Macs. This is the political argument for the Foundation fostering independent research bases in the South; and also for winning support among those governments, against the day when treaties are signed, or the UN votes, or the World Court weighs up the pleas. (Savage says some things in the book which betray economic and political positions not thought out. For instance, there is the picture of Aquarius-built airships ferrying spirulina to famine-struck Third World villages: a band-aid application which misses both the values and the dangers of cheap protein, and could be quite offensive to peoples who have been working to build up their agriculture with modern varieties, with debt, capital starvation, and consequent poverty as the reward.) 3.12 Bifrost: Operational Costs. -------------------------------- Very little space in the book is given to the stage between the building of Bifrost and of the full-blown space colony Asgard. Unfortunately this elides several interesting issues. Savage has Bifrost commencing operations as a short track up Kilimanjaro, cargoes and trained personnel shooting the tube at 30 gravities. Before this, the testing period could be quite long. The array of homopolar generators would seem to need a lot of maintenance. They must be tested on the "waverider" delta-shaped vehicles in all configurations of loading, imbalance, partial failure, etc. If one of the generators stuttered, the following ones would have to switch instantly to stabilizing and decelerating modes. The interaction of generator and vehicle through the speed-range, in the presence of vibration, air leaking into the tube, and so on, is a new physical phenomenon, which must be checked empirically against simulations. Also, having got waveriders into orbit, the art of getting them down again would have to be explored, by teleguidance presumably, before humans are ready to go up. Savage specifies a vehicle with a crew of 6, plus up to 25 passengers, or cargo; payload mass 4 tons, payload bay about 8 metres long. I miss any mention of a de-orbiting rocket system; this would have to be contined in the 5-ton vehicle structure. Ideally, Bifrost could launch vehicles at a rate of one each five minutes. At the point where one or two per day becomes reliable, they can undertake the deployment of the Valhalla construction shack. A crew of six could live in and out of the payload bay for weeks, a la Shuttle. A rendezvous of several ships in orbit would give plenty of redundancy for emergency re-entry. A dozen crews could work on the Valhalla job together. Compare this with Shuttle-borne operation. Discussions in the Internet sci.space group a few years back, about the costing of Space Station Freedom, assumed two or three Shuttles in service, and very few astronauts on the job. Every EVA hour counted, and was costed according to the Shuttle launch cost. Having built Bifrost, at whatever cost, the Foundation is in a very different economic situation. Savage has only a line item, "Launch capsules, 0.25 x $ 10^9". Does this mean, apiece? His entire position hangs on the vehicle cost. Other discussions of coilgun or laser-launch systems have assumed that the vehicles will be cheap, and usually that they will mass a ton or less. Savage's "waverider" vehicles as described above, would be engineering marvels. Savage postulates a launch rate of 3 per hour. If each vehicle takes a day to return to Bifrost, a fleet of 72 is required; for a 6 hour round trip, a fleet of 18. If the fleet is to cost only $ 250 million, that is $ 3.4 - 13.6 million apiece. I find it hard to believe that such a high-performance craft could be built so cheaply; also, Savage proposes that the 30,000 C shockwave temperature is to be handled by an ablating layer on the craft. Re-surfacing and other maintenance must be added to the round-trip time. Alternatively, a fleet of 72 at $ 0.25 billion each, is $ 18 billion; to be compared with Savage's $ 25 billion for Bifrost as a whole. Operating costs are assumed to be about the same as the capital costs, over 30 years of operation; i.e. $ 0.83 billion per year. $ 50 G / 4 kg G = $ 12.5 A launch rate of 3 per hour, times 5 tons per launch, gives 360 tons per day, 131450 per year, or about 4 million over 30 years. Cost per kilogram is given as $ 15 - 20, which accords with $ 50 billion / 4 billion kg = $ 12.5 / kg. If the vehicle costs were an extra $ 30 billion, we would get $ 20 / kg. Now even $ 100 / kg, or $ 100,000 / ton, would open radically new space markets. Communications satellites could be launched in hundreds; private endeavours in materials processing would be affordable. Rather than destroy the market for rocket launchers, Bifrost would seem to open a new one, in lightweight rockets or components massing a couple of tons, with delta-v of a few km/s. Asteroid prospecting would be immediately practical, although extraction and processing would need larger-scale, possibly crewed installations. In particular, the Moon is in reach for life-support cabins or additional Valhalla bubbles propelled by lightweight rockets. Moon-base and mass-driver components can be landed and assembled, and in a couple of years a flow of materials Earthward can commence from the Moon. Earth-orbit-crossing asteroids are to be mined for kerogen, a kind of tar; this being the most accessible source of carbon and hydrogen. 3.13 Valhalla to Aquarius: Profitablity --------------------------------------- Valhalla is the bootstrap by which the fully-fledged Asgard bubble-cluster raises itself. In this scenario, it should be remembered, the Aquarians and associates have had a generation to design and test components. It is a matter of scaling up the initial bubble and eliminating faults on the spot. Savage considers communications to be Asgard's major service, taking advantage of large microwave reflectors with very precise Earth-surface resolution, to dominate the personal phone market. I find it hard to believe that the market could be taken from other communications companies, unless the Aquarians are able to beat them consistently to patents, along with all their other activities. However, as with Aquarius, the terrestrial benefits of the synergy should be noted. (These are commonplaces of the perennial debate on the value of space; but to some extent, they have seemed less worthy of discussion as the O'Neill space colony vision of the '70s receded. I think they are always worth another look, whenever the period discussed covers the first half of the 21st century.) 1. Biotechnology. In space, the "third green revolution", recombinant genetics in algae, bacteria and fungi, can proceed without danger of contamination. Only the non-living end products need emerge from the cultivation vessels, after irradiation to kill the remaining cells. The same could be done on Earth; but space distances and solar radiation make for a very effective quarantine barrier. 2. Electric power. Solar power satellite proposals have tended to founder on launch costs and on the bulk of radiators, conversion and transmission systems, etc. The first kind of objection is presumably wiped out by Bifrost's capacity, hundreds of kilotons per year. Current advances in microwave generation make a dent in the second kind. Seen in isolation, SPS was not a good reason for space transport; in Savage's picture (as in O'Neill's) it is part of a synergy: if we make the effort at all, we get high-power microwave beaming thrown in. (Savage's power unit is a 200 meter bubble generating 17 MW(e). 100 of these make 1 GW(e), if transmission and reconversion efficiency is 60%.) As mentioned above, OTEC can take up a reasonable projected demand for power, a few kilowatts for each of 10 billion people, with tens of thousands of plants each turning over gigaliters of sea-water per day - and possibly liberating imprudent quantities of nitrates. However, an Aquarius platform at any latitude would make an excellent base for a microwave rectenna array, receiving periodically from power satellites in off-equator orbits, and storing it in SMES or as hydrogen. As a secondary scenario, radioisotopes from terrestrial nuclear power generation could be shipped up Bifrost in hundred-kilogram lots, which could never be supported at Shuttle costs. 3. Transportation. One major reason for this increased electrical supply is, that we will be wanting to shift most transport to some kind of methane-hydrogen-electrical economy over the next couple of generations. Growing cities will need more substantial electric-rail systems than we now expect, and more traffic in liquid natural gas. Space-to-vehicle microwave transmission is also a possibility. Health and communications issues may present impassable snags, but technical feasibility at present does not seem to be in doubt. With moderately large transmitting antennas, a microwave beam can track a target a meter across. Small helicopters have been driven in microwave beam experiments as far back as the '60s; lighter-than-air cargo vessels would seem to be appropriate applications. Whether electric motors have the power-to-weight ratios for something like a present-day passenger aircraft is another matter. To see how far this can be taken, see _The Future of Flight_, by Dean Ing and Leik Myrabo [Ref. 3], where it is proposed that mighty aircraft and SSTOs be powered by gigawatt laser beams from above the atmosphere. The Millennial Foundation ought to make it a priority, to have Baen Books re-publish this visionary classic. To step back to space applications, two kinds of light interplanetary ship would be available to Valhalla at a fairly early stage. One is their standard solar-collector "power bubble", 17 MW(e) at 35% efficiency, employed as a solar thermal rocket (50 MW) using Lunar oxygen as propellant. For higher power, a laser could track a target that size for thousands of miles. Once they can set up a laser system in orbit (not forgetting the radiators), an Earth-to-orbit vehicle could be reloaded with ice and kicked off at 4-5 km/s. 3.14 Asgard and Beyond ---------------------- Beyond this point, Savage's argument merges with O'Neill's space-colony scenario. O'Neill started his investigation by asking his students, "Is the Earth's surface the right place for an expanding industrial civilization (think big now)?" The scheme required Space Shuttle costs to be much lower than they turned out to be. In the context of Savage's arguments, the whole scheme is ripe for reappraisal, from the initial question on. Much of _The Millennial Project_ remains without comment here. Readers familiar with the perennial space debate will be surprised and maybe skeptical at the proposal for zero-gravity, oxygen-atmosphere spheres, rather than traditional tori or O'Neill syle cylinders. Neither is there any discussion of tethers, or nuclear fission. I don't fault the treatment for this; it would be impossible to compare many competing options while keeping the clarity of the proposal. It is sufficient that Savage presents one option which, if it works at all, works as a self-replicating unit for interplanetary colonization. In Savage's own terms, I note one gap in the integrity of the total project: the relatively small capacity of the Bifrost system. Ultimately, the book comes out with some tens of billions of humans living on Earth, trillions in space; and connecting them, a few launch systems capable of a few million people per year. 3.14 Conclusions ---------------- _The Millennial Project_ issues a challenge to everyone who sees space colonization as a rewarding policy for the 21st century. It is possible, says, Savage, to bypass the present dependency on government for launch-system research. Further, it is possible to bypass some of the implications of the rocket equation, and go straight to a system which can be extended to several million tons to orbit per year. For myself, the more important challenge is the Aquarius concept. This could be proven starting immediately, by undertaking a few researches, each valuable in its own right. These are: (1) OTEC applicability on the large scale; (2) controlled algal blooming using deep-sea nutrients; (3) marine construction by electrolytic deposition from seawater. Should Aquarius prove practical, it would meet one of the pressing needs of the present time: a utility structure suitable for rapidly-growing tropical coastal cities, which can be produced from abundant natural resources, and which is powered from a still-abundant naturally replenished energy source. All the alternatives have costs, potentially severe: overuse of natural fresh water supplies; import costs for fuels; committal of valuable land areas to energy generation; facilities for securing and reclaiming radioisotopes in quantity. Failing to meet these costs implies failures of the system; succeeding in meeting them implies decades more of economically impeding indebtedness. For these reasons, Savage's proposal ought to be considered by people with expertise in the relevant fields. His Foundation would pay handsomely, if it only succeeded in mounting the conferences and publishing the findings, on the critical Aquarius technologies. The Aquarius agenda offers hope to environmental, developmental, libertarian and pro-space constituencies. There always was potential for alliance among these, for developing cleaner high-tech solutions in food, water, energy and transport; but the solutions so often were too expensive, that the debates foundered, and the futile confrontations of the '60s and '70s re-emerged. _The Millennial Project_ is the welcome return of the High Appropriate technological vision, this time claiming not only a cleaner, more hopeful Earth, but an open road to space. 4. Personal Postscript ---------------------- Any discussion of space has to play against the backdrop of 21st century prospects. Is civilization about to hit the limits, or will we coast through on innovations financed by higher prices and more effective research? There is a general craving for solid figures, and if we can't get those, we will probably quote flaky ones anyway. I presume that the probability of achieving any given figure is a function of how many tickets we buy in technological lotteries. At present it's a buyer's market in labour, and a seller's market in intellect; unequalizing as that is, it does reward the educated, which continues to feed research. I also think, sadly, that the price of the research tickets will increase, while the winnings will be increasingly taxed. The environmental impact statements will grow longer; the number of parties disadvantaged by innovation but protected by law will grow larger. Individuals will be jealous of diminished choice, regions of their natural resources. It will become harder to implement technologies on the large scale. (Nothing could be more innocuous, at first glance, than the personal computer; still, Silicon Valley was a public health scandal for a number of years; for example.) It is no longer enough to find a new way to accomplish a task. We have to find ways that are sustainable, clean, and economical. Research is a critical environmental good. I think the emergence of new technophile initiatives such as the Millennial Foundation would be a good thing. I think it would be a good thing for the nations of the South to become research leaders as soon as possible. Finally, I think it will be a very good thing when, inevitably, we set up in space, and can vigorously carry out research in such areas as radical biotechnology, nanotech, and high- energy materials processing, without infringing anyone's health or rights. Final note. In a section of this review which I've edited out, I wrote about Savage's envisaged Millennial Colonists: "There has never been a nation quite like them; or a business, or a religion." Which made me wonder if that was true. I thought about it; and shortly thereafter, took a week away from the review, reading the history of the pre-WW2 Zionist settlements in Palestine. I found myself intoxicated with admiration, and appalled at the unforeseen inevitable tragedy. It also left me in no doubt that what Savage proposes is possible - if he can find men and women of the same stuff. 4. References ------------- %T The Millennial Project %S Colonizing the Galaxy in Eight Easy Steps %A Marshall T. Savage %I Little, Brown and Company %D 1994 %G ISBN 0-316-77165-1 (hc) %G ISBN 0-316-77163-5 (pb) %T Macrolife %A George Zebrowski %I Futura Publications Ltd %C Great Britain %D 1980 %G ISBN 0-7088-8060-0 %T The Future of Flight %A Leik Myrabo and Dean Ing. %D 1985 %I Baen Enterprises %C New York, N.Y. 10018 %G ISBN: 0-671-55941-9 -------------------------------------------------------------------