In Marshal Savage's TMP the Solaria phase concerns the colonization of the solar orbital space of our solar system and the ultimate form of habitat civilization will create there. Thus it represents a sort of climax to the 'story' of that civilization's projected history. While this story continues in his Galactia phase, that phase is essentially about the spread of that Solaria civilization, a replication of it from star to star across the galaxy. And so Solaria really represents an ultimate form for human civilization as a whole.
This is a more abstractly depicted phase compared to the rest of the book, his vision of human habitation in this phase based primarily on improvement and expansion of the type of orbital habitat he describes for Asgard, repurposed into a solar orbital habitat of much larger scale and also an enclosure for whole asteroids or planetoids, hollowed out, landscaped, and transformed into internally illuminated microworlds. In preparation for Galactica, we also see the sun harnessed as a power system like never before, its poles capped by vast high energy collectors which rely on the pressure of the solar wind to keep them in their non-orbital positions and which beam their collected energy to points about the solar system and bottle anti-matter particles in vast quantities to be used as a fuel for Galactica's starships.
This is a compelling vision but seems to only provide a clear picture at the macro-scale, offering only glimpses of the lifestyles and habitat this civilization would offer and no discussion of the evolutionary process which takes us there. There's an illustrative story of an imagined 'Space Family Robinson' establishing a homestead from an asteroid and in TMP's few illustrations where we see glimpses of a fantastic shroud of golden pearls surrounding the solar system, each an exteriorly identical yet internally personal microworld inside which people live angel-like, floating in zero-g garden environments. There seems to be a parallel to the symbolism of his cellular structured Aquarius and Asgard -human civilization as a solar-system-spanning macro-organism. But just how do we get there? What is life like in these bubbles? And what of life on Earth and the presumably colonized and in some cases 'terraformed' planets?
I envision the Solaria stage in the context of two key technologies which Savage, curiously, gave little attention to but which are virtually inevitable by this period of time and may emerge together, mutually interdependent; nanotechnology and artificial intelligence. Thus I see the evolution by which we arrive at a solar-civilization as reflecting the evolution of these technologies and an evolutionary competition between a number of different modes for habitat and lifestyle they would sequentially enable.
And, as I've noted elsewhere, I see future human society as ultimately embodied by what I've dubbed a 'transhumanist spectrum' of being ranging from the purely and naturally (as 'natural' as any human can be being the product of generations of medical technological interventions) organic to the completely inorganic and virtual. Myriad and mutable, with various degrees of cybernetic or biotechnological augmentation, and yet all intrinsically human. This is the future of humanity.
Visions of the future have tended to date toward an image of uniformity. One kind of human being -usually aryan- in one kind of ultimate habitat and one ultimate ideal social system. It's as if evolution could ultimately only produce a single right answer. But nature demonstrates for us the very opposite. Evolution works because it continually arrives at new answers to the same questions. Diversification is critical to the persistence of life -and similarly critical to the persistence and expansion of civilization. And so I envision a highly diverse future. A human race which explodes in physical and cultural diversity as these key technologies enable the human mind to increasingly refashion and reengineer both environment and body for reasons practical, whimsical, and aesthetic. And I foresee a human habitat which likewise explodes in diversity as we reach out to inhabit an ever growing number of environments with an ever-burgeoning spectrum of lifestyles. We obviously cannot predict or hope to describe all the possible variations in habitat and lifestyle the future may have in store. But when we place these two key technologies in the context of a number of known environments and the forms of habitat we have previously described for Aquarius, Asgard, and Avalon, we can arrive at visions for some potentially dominant forms of habitat and start building from that a more detailed picture of our ultimate solar-civilization.
As I described in previous articles, I foresee the development of nanotechnology as progressing in a series of stages building on each other's advances not unlike technologies of the past. These stages are Statistical Assembly (where we are today), NanoLathe, NanoChip, NanoFoundry, NanoFoam, and In-Situ Assemblers. We won't go into all this again for the sake of brevity. What's important here for this discussion are the kinds of artifacts each of these stages will be able to produce and, most importantly, a series of key new materials which will effect the type, performance, and scale of habitats that can be produced. And here they are in order of their likely appearance;
Crude NanoFiber: A product of crude Statistical Assembly already realized but only beginning to develop techniques for mass production. Consisting of short loose lengths of carbon nanotubes and later short multi-fiber threads, mats, and 'felts', it's primary structural use is as a reinforcement admixture to materials which have previously employed fiber admixtures like polyester and carbon fiber (the latter made from polyester), fiberglass, and alloy fiber. This would include things like concrete and ceramic, pultruded plastics, and molded carbon-carbon composite parts (carbon-carbon composites are those made with carbon fiber reinforcement in an epoxy matrix which it then itself reduced to a graphite by heating in a carbon monoxide atmosphere) and will result in a great improvement in their basic performance. We've already discussed some possibilities of materials like these, particularly its use as a homogenous reinforcement admixture for concrete, geopolymers, and regolete or regolith-based concretes. Crude NanoFiber is also already producing a variety of similar incremental improvements in existing microelectronics, microphotonics, and micromechanical systems but the one truly new artifact it may soon produce is a non-chemical adhesive NanoVelcro technology where special pads of clustered NanoFibers work like an extremely strong Velcro on most any surface and material. We are not likely to see any really new kinds of architecture or space structures as a result of NanoFiber based materials but what we will see is an increase in spans and lightening of structure as a result of the improvements in strength-to-mass performance of these composites. This may reduce the mass of structural components -especially in vehicles and pre-fab structures- and make more radical non-Euclidean forms more common in contemporary architecture and larger than ever before.
True Nanofiber, NanoRibbon, NanoFilms. and NanoCell Foam: A product of advanced Statistical Assembly and/or NanoChip systems, these relatively simple nanomaterials will produce very great, if still incremental, improvements in many existing composite materials but will also enable entirely new forms of structures, in particular the orbital tether system based Space Elevator and new forms of habitat based on pneumatic and 'wound' hull systems of vast scale. NanoCell Foam -which should not be confused with NanoFoam described later- needs a little explanation. This would be a rigid panel material formed by cross-linking fibers in NanoFilm layers to create a cellular structure, probably with cellular inclusions like today's honeycomb panels but on a microscopic scale. It would represent the first rigid 'diamondoid' material and allow for panels mere millimeters thick to serve as flooring and bulkhead panels. Note also that with the ability to create these materials comes the ability to integrate some electronics and photonics devices into them through laminate, lithographic, and film deposition processes; particularly photovoltaics, organic LEDs, microcapsules with reactive components such as eInk and phase change materials, holographic filters, touch pads and touch screens, and more. Combining these materials with the capabilities of NanoVelcro or NanoChip based 'molecular knitting' we may be able to realize the in-situ construction of extremely vast membrane hull systems much as Marshal Savage envisioned but it remains an open question whether they can ever function in the way he originally imagined. However, the creation of very large hull systems akin to TransHab is likely as would be the easier fabrication of inner-hull systems for the EvoHab structures we've discussed previously. We can also anticipate the use of super-pressure rigidized membrane truss components as an even lighter alternative to composites. Wound hull systems -an evolution of EvoHab systems based on laminating NanoRibbon into monolithic hull skins of incredible tensile strength- offers the prospect of creating classical rotating artificial gravity habitats of scales far greater than ever previously envisioned.
On Earth, we have the potential to realize some astounding things from these materials. NanoFilm windows may replace most glass and perhaps become the basis of building systems using ultra-light pressure-rigidized components. Imagine roof beams and floor joists weighing mere ounces! Pressure-rigidized components could also replace the spar based structures of aircraft wings or the truss based structures of high performance automobiles. Permanent hurricane resistant homes able to handle most any climate and with built-in power collection and lighting could be made from structures little more than elaborate tents. Super-pressure pillow-panel domes combining NanoFilms, and NanoFiber or super-pressure truss tensegrity space frame systems will be able to achieve scales impossible today. Buckminster Fuller's dreams of enclosing entire communities under domes will be quite feasible. We may also be able to realize the first vacuum lift airship systems -dirigibles based on the use of vast tensegrity truss supported lift cells that contain a vacuum rather than a lighter-than-air gas, leading to a radical reduction in the cost of airship use and the ability to make permanent arial structures of great scale. Imagine aerial buildings little more than vast tensegrity tent structures lofted by vacuum cells or vast solar power systems consisting of just lift cells and laminate photovoltaics -possibly employed both to produce power, provide wireless telecom services, and to shade communities in locations worst effected by global warming. Tent-like structures may even be usable for habitats underwater, resisting water pressure by membrane tension rather than internal pressure.
In-Vitro Diamondoid: A product of the NanoFoundry stage of nanofabrication technique, In-Vitro Diamondoid is essentially an alternative for all materials which we currently cast, mold, lathe, or machine tool in some way. And in addition to being an alternative with incredible basic physical performance, it would also offer the ability to integrate an infinite variety of mechanisms within its structures and fashioned simultaneously with it. It's with this technology and class of material that we see nanotechnology really achieving a ubiquitous impact on the civilization, the fluid tank based NanoFoundry becoming the basic fabrication technique for most of its artifacts. It's also here that Artificial Intelligence becomes an inevitability due to the sophistication of electronics and photonics this means of fabrication affords and so would start being integrated into the fabric of civilization with so many kinds of subcomponents having the option to integrate what today would be supercomputer class digital processing capability and with so many artifacts now being made monolithic rather than assembled. What do I mean by 'monolithic'? Some readers may recall my past work on the JoeyPad portable computer project and it's 'monolithic' variant called the M-Joey and later dubbed the Geode. This device consisted of a solid ceramic composite shell integrating a solid ceramic pychromatic display, near-field-imaging touch screen, and WiFi helical antenna inside which all electronic components for the device were surface mounted and then permanently sealed inside with even power charging provided by induction or a small optical power port. With the advent of NanoFoundry fabrication, vast numbers of artifacts will take on this same approach to solid-state design, but with the bonus of diamond strength for their basic structure and the ability to fabricate-in-place extremely intricate electronics rather than having to add or assemble them. Whole devices fabricated like an individual IC chip.
While the products of NanoFoundry production will revolutionize many things, it would actually offer only an incremental improvement to the existing strategies for space habitat design, producing no new types of large structures of its own. This is because it is limited in production to what can be fabricated within a process tank providing the necessary eutactic environment for its assemblers. So to make a habitat hull shell from diamondoid would mean first erecting a fluid enclosure as large as it is or engineering some kind of mobile fluid-tight shell enclosure akin to today's sliding form systems for concrete -or one would use modular components and another similar kind of enclosure over seams to molecularly 'knit' them together. This will certainly be done for small structures but for the largest habitat development it may, due to the complexity and tricky temporary hermetic seals of these mobile enclosures, be limited to the production of modular rigid components such as space frame components. Still, the improvements in strength-to-mass, thermal, and damage resistance performance would be dramatic and we could see the integration of many devices into these components -imagine, for instance, space frames that are self-illuminating or feature actuators to function like Hoberman structures. One very significant aspect of this would be the ability to greatly improve upon the ability to make light-transmitting structures with image correction, light intensification, and integral energy collection and thermal compensation. This would allow many space habitat structures to be virtually transparent in spite of being composed of very thick materials like regolete, thus indirectly realizing Marshal Savage's dream of transparent hull habitats. This would also allow on Earth the creation of super-insulated buildings which are completely opaque on the outside yet completely transparent from the inside.
Adaptive and Polymorphic NanoComposites: This is an advance on the potential of In-Vitro Diamondoid materials deriving from the integration of micromechanisms and microprocessing into the matrix of components produced by NanoFoundry methods. These materials would actually consist of arrays or colonies of nanomechanisms with the ability to reconfigure their organization or characteristics in response to environmental conditions or commands sent through a microprocessor network integrated with them. Though the mechanisms would be composed of diamondoid materials, as a whole they would not be as strong as true solid diamondoid structures because of the limitations of the interfaces between the individual micromechanisms and may employ a solid diamondoid 'skeleton' to supplement their strength. These materials would be used primarily for things like aircraft wings which can adapt their aerodynamic characteristics on demand, artifacts with the characteristics of Hoberman devices, synthetic self-repairing and thermally adapting skin materials for various structures and machines, dynamically color-changing materials or extremely large digital displays, and sophisticated force-feedback user interface devices. In space they would find home primarily as self-sealing hull systems and thermally and optically adaptive skin systems. Again, their impact on habitat design would likely be incremental. This technology could also offer a key solution to the scale limitation of the NanoFoundry by allowing for the creation of relatively small rigid components with molecular knitting mechanisms in their edges which allow them to self-fuse into very large continuous structures.
Though referred to as 'polymorphic', these materials and components would actually have very specialized functions and a very limited range of transformation of form they could perform. However, true polymorphic systems based on nanomechanism 'colonies' with weak interface but very high and rapid morphability are likely for some robotic applications, toys, art, and possibly even small buildings with light load/strength demands.
NanoFoam: This is both a material and a fabrication technology and would represent one of the most powerful advance for the entire Diamond Age. NanoFoam is the integration of the capabilities of Polymorphic NanoComposites with the capabilities of the NanoFoundry, creating a self-transforming diamondoid matrix for colonies of eutactic assemblers. I have previously envisioned this as the product of the pursuit of increased portability for NanoFoundry systems through the development of means to self-assembling custom shaped process tank structures or 'chrysalis shells' based on the types of nanomechanisms used with Polymorphic NanoComposites. The basic limitation of Polymorphic NanoComposites is the necessary specialization of their integral nanomechanisms. At this stage in future history, true nanoassemblers with the full capability of the NanoFoundry will still require a eutactic environment; an enclosure like a tank with an uncontaminated and controlled fluid medium for them to move around in and extract molecular components from. The ambient environment is too hostile for their fragile structures. By creating a kind of hybrid colony where eutactic assemblers are protected within a skin of Polymorphic NanoComposite structures one creates a system capable of truly unlimited -albeit slow- polymorphic capability with the strength of a core diamondoid structure. You can imagine this as being rather like a living organism which has a skeleton that supports it, a flexible expandable skin that protects it, a blood stream of fluid that conveys materials internally, and a collection of cellular mechanisms that move around in this fluid medium and build and maintain all the parts for everything.
NanoFoam would represent one of the greatest technological advances in human history; a self-fabricating, self-replicating, self-transforming, self-recycling super-strong material with its own built-in artificial intelligence that can either make or assume the form and function of any artifact on-demand. It is likely to become the primary material of civilization and would both radically advance existing forms of human habitat around the solar system and enable the creation of new vast habitats whose carrying capacity could be equivalent to hundreds of Earths! It is likely to even become the physical material of life itself for the more cybernetic end of the transhumanist spectrum.
In-Situ Diamondoid: This would be a product of the advent of the In-Situ Nanoassembler. These would be the most sophisticated form of nanoassemblers; ones which can survive and function in the ambient environment. This would give them the ability to fabricate and recycle things in the ambient environment without enclosures or fluid mediums using their own microscopic structures as temporary scaffolding and a communications network as they work. In-Situ Diamondoid is essentially the same as In-Vitro Diamondoid with the exception that because it is made 'in-situ' it becomes possible to make, expand, and adapt diamondoid structures complete with their integral systems to any scale without an enclosure or chrysalis shell. In-Situ assemblers can also be freely mixed into the materials of the ambient environment -such as soil, water, air, industrial materials, and people's bodies to perform assembly and recycling operations on demand in response to various forms of 'beacons' and communications systems. It would be as though the matrix of all matter had been made intelligent, ready to be summoned to restructure itself on demand.
In-situ nanoassembly is what most people envision when they imagine what nanotechnology is. It's what both futurists and science fiction writers most often depict as 'basic' nanotechnology. But it will likely be very difficult to accomplish and, in the presence of NanoFoam technology, it would be rather redundant since the most sophisticated artifact it could produce would be structures like NanoFoam, which would be self-replicating anyway. So it's an open question whether there will actually be a need for in-situ nanoassembly when it becomes possible or if it will simply be a footnote to the Diamond Age -a minor incremental improvement to a NanoFoam based civilization.
Now that we have a picture of the new kinds of structural materials and technologies we can look forward to, let's consider Artificial Intelligence and its possible impact on all this. In the original TMP this technology was only briefly touched upon in descriptions of Aquarius, which was curious since odds are probably fairly low that it will be realized -or if realized only in some nascent form- by the time the first full-scale marine colonies are realized and largely unnecessary for doing that in any case. But it is clear that, whenever AI is realized, it will have significant logistical impact on the pattern of all civilization's development.
I foresee two stages of AI development; non-sentient AI and sentient AI. The former will likely be realized in the form of fairly specialized application software offering three basic modes of use; assistive, passive/augmentive, and autonomous. Assistive AI will take the form of features embedded in application programs or taking the form of specific AI tools such as personal assistant software. It works through an interactive dialogue with the user upon which it relies for instructions and information.
The most advanced form of this type of AI software will likely be embedded into research and engineering tools which at first will be highly user dependent but eventually evolve the capability for performing increasingly comprehensive tasks independently once given the necessary parameters. This will result in Intelligent Functional Engineering systems capable of completely designing, engineering, and testing in simulation a large range of artifacts. Also, Intelligence Research Systems which perform complex scientific research, though relying primarily on externally supplied data. These kinds of tools won't always be capable of the most elegant solutions but they will tend to be the most thoroughly analyzed and reliable because of these systems brute force capacity for quantitative analysis without mental fatigue at a vastly accelerated pace and with a very vast catalog of functional parameters. The impact on space development from this will be by its great power as a means to leverage technically skilled manpower and reduce the cost of systems R&D. Today huge teams of engineers are often needed for development of most space systems but with tools of this magnitude the design and engineering of the most sophisticated systems may literally be reduced to a one-man task!
Passive/Augmentive AI are systems which function largely behind the scenes without direct human instruction but yet in constant interaction with humans and various sources of information to which they respond by dynamic feedback. I have previously described examples of this in my transhumanism discussions with the model of the wearable and eventually implantable cell phone which augments human communication by being able to listen-in on our communication and act as an intermediary -allowing us to speak what we think to the cell phone without actually speaking by being able to intercept the sub-lingual muscle signals generated when we think about speaking and translate them into synthesized speech sent to the phone. Similarly, one could make a cell phone that automatically translates the languages of each speaker. Another model I like to use is the political lie detector. A program which listens to TV broadcasts of politicians with us and compares what they say in real-time to an Internet database of their own record and other factual information, generating pop-up notes as in that once popular Pop-Up Videos show to inform us when the speaker is lying, stretching the truth, or simply wildly incorrect about known fact. I foresee countless applications akin to this, augmenting our casual mathematics skills, filtering and collating information for us, overcoming the limits of our memory, and helping us navigate the more complex aspects of daily life and doing so in such a subtle fashion we are barely aware of it not being an extension of our own minds. The impact of this technology on space development will be just as subtle as its integration into our culture. There will be no obvious direct effect at all but in terms of its ability to augment human capabilities it may have a powerful long-term effect, altering the way we communicate, organize, and interact while incrementally immersing society into a hybrid environment where virtual reality and 'data space' overlaps the physical world -at least within the footprint of WiFi networks.
Autonomous AI consists of programs designed to perform complex tasks largely independently of human control but with pre-instructions and pre-parameters that are human set and with a requirement for periodic human interaction. I see this kind of AI finding its uses in two key applications. Robotics, obviously, but also entertainment in the form of systems designed to bring life and personality to animated characters in games, virtual and robotic companions, and simulations. Today robots have become a great focus of AI research but this is a much more costly avenue for development than entertainment simply because of the much higher cost of physical hardware as opposed to virtual hardware in a VR environment. So it seems likely that this may eventually overtake robotics as the primary venue for AI research -games clearly make more money today. This is the most advanced form of non-sentient AI, combining the capabilities of the other two types while adding systems for limited independent initiative and comprehensive human interaction. In its robotics applications, this form will likely have great impact on the pace of space development by virtue of its order of magnitude acceleration for the pace of telerobotic operations and its great enhancement of guidance control for spacecraft. This will again greatly reduce the necessary man-power for space activities putting more of them into the reach of individuals and small groups. Its entertainment applications, however, may be more critical to AI's evolution by being the basis from which Sentient AI is ultimately developed as a consequence of its purpose of emulating human personality. In order to create an effective simulation of the human personality one must, in effect, reverse engineer the human mind and in the process simulate or eventually replicate its functions.
The ultimate result of all this -the Sentient AI- will likely take the form of a largely self-contained piece of software perhaps initially dependent on somewhat specialized hardware architectures -at least until the mainstream computing infrastructure catches up to them- but ultimately becoming highly portable. (serial processing systems with monolithic operating systems would not be conducive to this type of software. A more fluid massively parallel OS-less environment where software exists as discrete entities and resource allocation is passive and transparent is much more likely) AIs may sometimes employ robotic platforms but it's my suspicion that if they originate in entertainment systems based largely on virtual environments they will tend to favor life in virtual environments simply because, for a long time to come, the 'experiential resolution' of the 'avatar' based virtual body image will tend to be far greater than that possible by robotics. In other words, it's easier and much cheaper to replicate the entire compliment (and more!) of human senses and abilities purely in software than to replicate them with artificial mechanisms mimicking the architecture of the organic human being, with the end result is also likely to be much more aesthetically pleasing and socially acceptable. It's a choice between looking and feeling acceptably human but only on a video display or having more direct interaction with the 'real' world but looking and feeling like an escapee from The Hall of Presidents or a SciFi movie. And there is much to be said for the lifestyle benefits and essential economy of the virtual habitat even if its interfaces to the 'real' world may initially be limited. This assumption could prove wrong, however, if the state of nanotechnology at the time Sentient AI is realized is so far advanced that the replication of robotic systems as intricate as organic life becomes commonplace. In that case a hybrid lifestyle of simultaneous presence in both real and virtual habitats is likely.
Sentient AI would not at first represent any practical benefit over the use of non-sentient AI from the perspective of the organic human being. In fact, they would be cumbersome. We treat tools as extensions of ourselves. It doesn't help our productivity to have to question and contradict us. But these won't be 'tools' to enhance human ability. Rather a new kind of independent person with great practical advantages as a potential space colonist. There is potential for a great acceleration in the pace of space development as a consequence of Sentient AI, however it would potentially come completely independently of organic human colonization depending upon the relationship this AI society establishes with its organic counterpart and how much interest it actually has in space. AIs would be supremely well suited to habitation in space because their needs are so minimal compared to organic humans, they have the safety advantage of being able to back-up their software in many forms and locations, and because of their ability to travel -literally- at the speed of light via radio and laser telecommunications. So were they so inclined, they could quite easily become the dominant form of life in the solar system in a quite short period of time. But owing to the fact that they are effectively immortal, they have little reproductive imperative beyond the desire for more individuals to interact with. And their habitat needs are so minimal and so indifferent to conditions that would be intolerable to organic humans, a very large amount of terrestrial space abandoned for any practical use by organic humans would be fully available to them. So 'leibensraum' is hardly an issue for them. And because they would be social organisms just like organic humans and initially relatively few in number, they would still tend to be dependent on the organic human society as a source of social interaction. Space habitation brings with it the social disconnect imposed by telecom latency and while AIs would be able to commute freely to and from locations in space in minutes to hours, they could not maintain meaningful interaction with the organic human society from a space location without having those organics with them in space. So they may be less inclined toward independent colonization unless there is something more critical compelling them to space ahead of humans. In my discussions on the M3 computer game I've eluded to one such possible issue; persecution leading to terrorism by segments of the organic human society. This is a distinct possibility considering human history to date and the current trends encouraging the growth and political empowerment of religious fundamentalism.
When combined with the emerging capability of nanofabrication, the potential of AI to accelerate space development is further amplified. The telerobotic settlement that once may have required a host of automated facilities to support itself might need only a few variations of the basic NanoFoundry to handle the majority of its production needs. And, with the advent of NanoFoam, everything you send to space would become its own AI factory with unlimited industrial capability. A payload as small as a soccer ball might be all that's needed to establish a complete settlement with structures of vast scale and comprehensive resource development in a matter of months totally without human intervention, this small package carrying with it the totality of the civilization's industrial and technological potential and the necessary local intelligence to deploy it -indeed even having the possibility of being a sentient being itself. With this kind of power space settlement could actually become a completely personal endeavor, any single person affording the means to create worlds of their own anywhere in space that's within reach within their lifetime.
Given this picture of the technology and key materials anticipated by the time of Solaria, what can we anticipate about the design of habitats across this eventual solar-civilization and the lifestyles they offer? I envision a number of important types of habitat that might emerge. Let's have a look at them.
These habitats may be the first solar-orbital habitats and would be a direct product of the Asgard phase's pursuit of asteroid mining. This concept was originally proposed in Marshal Savage's TMP as the basis of his vision of space 'homesteading' based on asteroid mining as a family venture. That may or may not come to pass but the habitat concept proposed is quite likely. The Shell Habitat is simply based on the excavation of an asteroid's interior volume through mining until one has created a vast hollow microgravity shell similar to the EvoHab habitats except that, instead of relying on an urban tree, the primary habitable structures would be spaces hollowed out of the rock of the asteroid with the habitat's core truss reserved for use as a lighting system consisting of a vast holographic diffuser fed by light gathered from vast external heliostat structures or using electric power. One or more MUOF like truss based structures would be anchored to the asteroid during its initial mining exploitation and would function as materials processing, docking, and launch facilities as the asteroid's interior is hollowed out, perhaps using systems similar in some ways to the large bucket excavators employed in terrestrial strip mining. Initial habitats would be quite similar to the excavated modular pneumatic hulled habitats described for Avalon, though based on a microgravity environment. Once sufficiently large, the interior of the hull would be sealed by the application of ceramic or epoxy coatings. The inner surface of the habitat would host most farming activity with the residential spaces shaded behind vast grids of hydroponics. A great deal of strata would need to be retained to maintain the structural integrity of the hollowed asteroid and so these structures may not be as thin shelled as Savage originally envisioned or feature the vast porthole domes while the unusual shapes found with many asteroids may lead to the use of multiple smaller chambers since they may be limited to a spherical or cylindrical forms.
The remoteness of the Shell Habitat would dominate the lifestyle of its early inhabitants. These will be places best suited to people with a high degree of self-sufficiency and a traditional farmer's attitude toward the pace of life. Savage was not far off in the suggestion of the asteroid as 'homestead' because, early in the history of asteroid exploitation, it may take such very vast reserves of resources to provide the necessary redundancy to insure a large enough margin of safety for a small remote community. But survival may require communities of a tribal scale, rather than the largely ineffectual 'nuclear family' of the 20th century. As nanotechnology enables a shrinking in the scale of systems in a life-support infrastructure and the solar-system-wide transit infrastructure grows more robust the Shell Habitats may evolve to a more urban aspect but for some time they may be quite private and isolated worlds relying on small communities of unusually capable people with a powerful pioneer spirit. Long-term -and with the advent of NanoFoam- these Shell Habitats are likely to evolve into the BioSphere's described later.
Geopolis Ring: This form of habitat was briefly mentioned in my past pieces and represents the ultimate evolution of the GEO based Asgard-type Earth-orbital settlements integrated to the orbital tether Space Elevator technology. It's actually based on an old idea described in abstract form in one of the legendary inspirations for the Space Elevator concept; Arthur C. Clarke's novel The Fountains of Paradise. At the end of the book Clarke describes a vision of the ultimate form of the Space Elevator; a series of tethers like the spokes of a bicycle wheel linked by a ring of urban habitat structure running entirely around the GEO orbit. As fanciful as this idea might seem, a habitat like this represents a logical extension of the technology from which the Space Elevator would be built combined with the technology of the EvoHab. An orbital ring structure would act as a stabilizer for the entire collection of SE tethers around the Earth's equator, allowing their expansion to larger scale and their additional deployment in locations that are less optimal than the initial marine locations. And as a habitat, this ring structure could ultimately become Earth's single largest community, with marine and land arcologies at its downstations and a vast collection of habitat structures along the ring. It may also become the greatest 'carbon sink' for the Earth, going far to ameliorate the atmospheric carbon load of the planet due to its great demand for carbon from which to build its Nanofiber and diamondoid structures. Being based in Earth orbit and needing only some of the first of the new Diamond Age materials to be realized, this may be one of the first kinds of 'superhabitats' -space habitats of urban megastructure scale- to be realized.
The Geopolis Ring would be built using the same technology the Space Elevator itself would employ, consisting of a Nanofiber/NanoRibbon tether just like the space elevator extending horizontally from the point of the GEO upstation. Using the technology of the EvoHab, this tether would take the place of a core truss structure for EvoHab manned habitats, MUOF facilities, solar power arrays, and hybrid rotating habitats, housing in its corrugated interior a linear motor driven transit system, communications, and power conduits linking together all the structures along its length. The interior organization and structures employed within the Geopolis habitats would be much the same as those described for the large EvoHabs of the Asgard phase -at least until the advent of NanoFoam where this material is likely to replace a great deal of the modular component structure originally employed in Asgard phase settlements. The key difference between Geopolis and Asgard settlementsis the potentially great open space of its habitat segments. Enclosures hundreds of kilometers long become possible, allowing for 'urban tree' habitats of vast scale akin to the Linear City arcologies that may appear on Earth.
The lifestyle offered by the Geopolis Ring would be basically identical to that described for the habitats of Asgard but its scale would be vast allowing for the creation of a diversity of more culturally and aesthetically specialized sub-communities. The basic technology of the EvoHab would be fully elaborated, allowing for these sub-communities to freely experiment in different variations on its aesthetics and function. Considering the very great length of the ring and the likely steadily shrinking costs of EvoHab construction, quite large habitat structures could even be built on the ring as personal residence. There is a possibility that, with time and experience, the Geopolis Ring may become dominated by either microgravity habitats or rotating artificial gravity habitats, the latter being more costly to construct but with the difference in cost narrowing with the advent of more sophisticated nanofabrication technique. Luckily, the flexibility of the structural technology on which this habitat would be based eliminates the need to pre-determine the use of any specific type of habitat structure. It can freely employ microgravity and gravity habitats and switch between them as needs change. It could even become dominated entirely by MUOF structures as a host for a completely inorganic community. As with all habitats of the Solaria phase, the replacement of its original structures with NanoFoam is a likely eventuality.
The Heliopolis Ring takes the concept of the Geopolis Ring to its logical conclusion in the form of a solar orbital habitat, most likely located in orbits just outside that of the Earth's orbit. It has the potential to be the single largest type of structure human civilization may ever create with a carrying capacity literally equivalent to hundreds of Earths!
Based in a true solar orbit just outside Earth's orbit and perhaps originating as a way-point facility for materials transported from the asteroid belts, the Heliopolis Ring has the option to begin in a fashion similar to that of the Geopolis Ring but without the core Nanofiber tether structure, using instead an axial truss conduit linking its various functional and habitable structures and with those habitable structures relying on much more heavily shielded hull systems. it's ultimate form, however, would be dominated by the creation of a single vast rotating habitat structure based on wound NanoRibbon hull technology as described in the article on Asgard but expanded to very great scale.
Marshal Savage was quite negative toward the notion of the artificial gravity habitat because of the obvious high cost of development the classic space colony concepts of the 1970s would have required. They seemed like overkill and there is no question that they would be impractical for the initial settlement of orbital space as outlined in Asgard and that they will always be less efficient in pressurized space utilization as only their microgravity core and perimeter inside surface will offer functional space. They also tended to present a certain Catch-22. They could not be built without a massive orbital industrial infrastructure and yet were assumed to be the basis of that very same infrastructure despite the fact that they would be uninhabitable until completed. But with the advent of diamondoid materials, advancing nanofabrication techniques, and AI to drive the exploitation of space resources the difference in structural and logistical complexity and development cost between the microgravity and artificial gravity habitat narrows. Savage bet heavily on the notion of the discovery of a fairly simple clinical solution to the problem of the physical deterioration caused by microgravity. It's a fair bet, but still speculation. If there is ultimately no practical clinical solution then there will be no other choice. Without that, full gravity habitats will be mandatory for permanent organic human habitation in space -with even surface settlements becoming only temporarily habitable. Certainly, the artificial gravity habitat is the only option for the full re-creation of terrestrial biomes. The notion of terraforming is misleading. We may eventually make planets like Mars seem Earth-like but any life we cultivate there will have to be re-engineered specifically for its very different environment and gravitation. It will not be a host to Earth life, only derivatives of it. There's nothing wrong with that but the engineering of new self-sustaining ecologies of new organisms is likely to be a very time consuming and unreliable process. Only where we have complete control of all environmental parameters -including gravity- will we be able to accommodate and transplant the full compliment of natural terrestrial life forms and their pre-existing ecologies and so for those for whom that is a specific goal -be it for aesthetic reasons or as an insurance policy for Earth life- rotating habitats may ultimately be the only option. And one must account for simple preference. Microgravity has its charms but also its inconveniences and while first waves of settlers will likely be willing to overlook the differences in their new home, subsequent waves of settlers may be progressively less inclined toward compromise on what they think 'home' should be like. If all things were equal in terms of safety and cost (and they may get quite close given the potential of nanotechnology and AI in concert), which would you choose? Thus one is compelled to consider the contingency of the artificial gravity habitat.
What is particularly interesting about the use of such habitats with Diamond Age materials, with their incredible strength-to-mass performance, is that their potential design becomes radically simplified while scale becomes vastly greater than anything imagined in the 70s. NASA studies have suggested that with Nanofiber based materials scales a hundred times greater than original proposed habitats become possible. With the more monolithic diamondoid materials, this shoots up to many hundreds of times greater. And thanks to the technology of EvoHab and its wound hull systems, it becomes possible to evolve such habitats to such scales over time, overcoming the critical logistical problem of such huge habitats having to be built all at once and over vast spans of time before they can become inhabited.
Heliopolis represents the ultimate evolution of such structures and we can imagine the Heliopolis settlement starting quite modestly, with a typical Asgard era EvoHab facility which adopts the use of wound NanoRibbon hull technology to create a modest initial rotating cylinder habitat most likely relying on optical conduits and light collectors at its ends to provide interior illumination through an axial holographic membrane diffuser wrapped around its original Asgard-style core truss. This would likely be a 'hubless' structure with microgravity facilities near its ends disconnected from the main rotating structure and accessed by shuttle vehicle deployed at the habitat core which rely on magnetic or thruster counter-rotation when they are launched. This overcomes the great complexity and cost of developing pressurized counter-rotating hub systems.
The wound hull technology -previously described in the article on Asgard- leaves an exposed portion of structure on its exterior to which modular shielding and other functional components can be attached just as with all EvoHab structures. This also allows new truss structures to be attached, serving as temporary scaffolding or as new permanent structure, allowing for the habitat to incrementally grow in all dimensions even as it's inhabited and in full rotation. The priority in habitat growth is likely to be in circumference before length as this expansion is less obtrusive to the inhabitants (it's all going on 'underground' from their perspective) and larger circumference translates to slower rates of rotation at the core making transition much easier. At the start the habitat may seem quite spherical in form as it makes most sense to start with the widest circumference one can even if it means a relatively narrow band of functional circumferential space. But the advance in materials strength is not going to be linear and so there will likely be a shifting between shorter phases of radial expansion interspersed in a more continual progression of axial expansion.
That axial expansion is what will eventually result in an arc structure and eventually a complete ring, filling an entire orbit. The arc of the solar orbit will be quite tiny in relation to the sectional diameter of the hull and so, rotating with its axis on the vector of the orbit, the colony can literally arc as its grows and continue to turn in place, the minor deformations in structure well within the natural elasticity of even diamondoid materials. And so what this eventually becomes is a vast torus rotating in place perpendicular to its circumferential axis while also traveling at orbital velocity parallel to that axis.
Of course, achieving that full ring would be the work of many generations and would produce a habitat of truly astounding scale. Using diamondoid materials, Helipolis has the option to achieve a sectional diameter of some 100 kilometers! Multiply that by the circumference of a near-Earth solar orbit and you get an interior surface area that could be hundreds of times that of Earth itself! A true ringworld but without the superscience. Whether the colony ever would actually achieve this scale is not clear or really that important. The settlers of this region of orbital space may simply never need that much space or may prefer a series of pocket worlds that can be more culturally self-contained. What's important is that the freedom of expansion through this design offers the option of this solar ring long-term should the civilization desire it and that this massive habitat offers the prospect of societies with populations many times greater than the entire Earth society without any of the population pressures.
The large potential size of the habitat and orientation perpendicular to the sun calls for some different strategies for the functional elements of the habitat. Rotational and orbital velocity would be corrected by use of a plasma-sail system which exploits the solar wind as a motive force on a dynamic basis, induction coils integrated into the hull switching on and off relative to the axial rotation of the structure to control both its rotation rate and orbital velocity by deflecting the natural stream of solar particles. The effective thrust of this system would be quite small but across the the large scale of the structure it would be significant while the very high inertia of such a massive structure would produce very high stability to begin with so corrections would be done over a very long time. The use of plasma ejectors would be used where even more thrust is needed -effectively creating a vast solar sail many times larger in area than the cross-section scale of the habitat itself. This system would also be employed as an active radiation shield during solar flares, its plasma ejectors used to generate a kind of magnetosphere around the habitat in advance of high especially intense particle streams. Using this system as a means of propulsion, the habitat would also have the option to traverse to higher orbits, the ring disconnecting to allow it to expand to larger circumferences. The simultaneity of coordinated orbital and rotational corrections would be sophisticated, since it needs to compensate for communication latency across the circumference of the orbital path. Across these distances, even the speed of light is rather slow and accumulated correction errors take as long to fix as to create, resulting in strains that could tear the structure apart. Thus a sophisticated network of sensors, dynamic structural modeling, and optical communication would be employed to give the entire hull structure of Heliopolis its own sort of sophisticated situational awareness -a sort of distributed neural network of vast area that gives the structure the ability to look ahead in time and synchronize its responses or even respond in anticipation.
Because of its orientation, Heliopolis would not be able to rely on sunlight communication and thermal radiating from its ends alone after it reached a certain length. Thus a means of both collecting light and dumping waste heat across the actual hull surface of the structure becomes necessary. The classic space colony designs were keen on the concept of deploying vast windows integrated into the hull system for light to enter from vast exterior mirror collectors and this was one of their most critical engineering challenges since these windows needed to have the same tensile strength as the rest of the hull system and be fully repairable in-situ without degradation to their optical properties as they encountered countless micrometeoroid hits over time. As I've noted previously, I feel that technologies of light 'transmission' rather than transparency is a more practical option and this is especially true here because, with a structure axially aligned perpendicular to the sun, it's no longer possible for hull windows to be static in position relative to the sun. So even if they were used, the light would be constantly shifting on and off over its interior surface. So, as an alternative, Heliopolis would exploit that external frame mounting feature of the wound hull system to allow for the attachment of a transmissive light collection and radiator array -effectively turning the entire hull surface into a single static window and thermal radiator.
This system would consist of arrays of holographic film panels stretched over space frame struts which create a kind of 'fly's eye' array over the whole outer surface of the structure, with half of it collecting light at any time as the hull rotates. Each panel would concentrate light into a terminal for a hollow vacuum core optical fiber cable which is linked to others in a fan-out concentrator network gathering light into large optical trunks which then penetrate the hull and direct the light along a few regularly spaced towers into the central core of the habitat. Here a light emitter port directs it into a tubular holographic light diffuser stretched along a tensegrity truss in the core, creating what appears like a long series of giant fluorescent tube lamps running through the core between the tops of towers. The arrangement of the collection networks would be such that the main trunks oppose each other in pairs or triplets so that the internal towers would appear like the spokes on a wheel in groups of two, three, four, or six and alternating in interval along the length of the structure. This way the light level transmitted into any section of diffuser is constant relative to the rotation of the outer hull surface. Inside these towers the light would also be filtered for energy use, the optical trunks running through them using concentrated photovoltaics and spectrum-specific membrane filters to extract energy from undesired portions of the optical spectrum, such as UV and IR. The towers would also control light levels to the core diffuser to generate a day and night cycle, putting all its incoming light to PVs when not used for illumination. This is a technology I expect to be pretty well developed by the time of Heliopolis as a result of its deployment in both Asgard and Avalon phases of settlement as well as with the Geopolis colony.
Using these same external mounts and fan-out networks from these towers the habitat would construct a radiator system using pneumatically rigidized membrane radiator panels stretched 'vertically' between the posts holding the horizontal light collectors. Linked to a network of coolant pipes paralleling the network of light collector cable, these would passively dump heat when they are angled away from the sun, turning half the hull into a radiator at any time. These external structures would, of course, offer no particular resistance to micometeoroid impact but they would still function even if punctured and when sufficiently degraded would be replaced and their materials recycled. This maintenance would be continuous and so, in addition to the optical and thermal network lines, there may also be a maintenance robot track following the fan-out network to allow for routine replacement. All these functions might thus be integrated into a single system of retrofit components.
Spacecraft access to the habitat is similarly complicated by its axial alignment and great length. Many industrial activities would be conducted on MUOF-like facilities largely independent of the rotating structure of the main habitat -orbiting independently nearby- and as the habitat grows the traffic volume funneled through its ends would become progressively greater. If the habitat went full-circle, there would be no ends to funnel traffic through at all, and so one needs to consider a very different strategy for spacecraft access. The solution I envision is a counter-rotation tram. This would take the form of a kind of inverse-railway where the tram vehicle hangs by its sides from a rail line consisting of a loop running around the sectional circumference of the habitat hull. Using mag-lev propulsion, the tram accelerates to counter the rotation of the habitat and achieve a microgravity state. It can then extend telescoping docking ports or transfer platforms for a brief temporary link to a spacecraft. This, of course, favors the use of containerized cargo and in some cases an entire small specialized spacecraft -most likely shuttles designed for accessing nearby microgravity facilities- might be locked-down whole to be carried by the tram. Once transfer is complete, the tram simply decelerates until it has matched its rotation to the hull and can dock at stations along the track loop. These stations would, logically, be located at the base of the same interior towers used for the radiator and light collection systems. This strategy might seem complex but may be less complex than the engineering of continuously counter-rotating hub systems.
Though Heliopolis may feature hundreds of thousands of such tram rings -especially if it achieves its full orbital ring shape- the distances between their stations would still be rather great along the circumference of the structure and so a sophisticated internal transit system would be necessary. But interior open surface area is precious and would never be squandered for exposed roadways so transit system integrated into the infrastructure of the habitat would seem more likely. I see this taking the form of two systems; a conventional PRT/PPT network integrated into sub-structure decks and a more specialized core transit system. The open space surface area of the habitat would be reserved primarily for residential and park use and for the cultivation of naturalistic biomes with simulated landscapes. But beneath this would be multiple levels of vaulted decks used mostly for farming, industrial activities, and storage with additional deck spaces within simulated landscape forms serving to seclude various 'underground' dwellings. It is within these subterranean spaces that the PRT network would be built -much in the same way as the PRT of Aquarius would be implemented. By this period the common propulsion for such systems is likely to be mag-lev with these PRT systems capable of very high speeds and vertical and horizontal travel, thus making them useful for both surface and core access. But the distances along the circumference of Heliopolis would be incredible making the use of even mag-lev rail systems too slow while the use of conventional high speed aircraft may be impractical even with such vast interior spaces. Thus a different means of transit in the form of a core based system may become necessary. This would consist of a magnetically propelled shuttle vehicle which relies on the microgravity conditions of the core and an extremely aerodynamic shape to allow for very high speed travel. The system would rely on an array of magnetic accelerator/decelerator loops behind the core light diffuser membrane tube organized in four or six conduits provide rail-like transit at near super-sonic speeds. Over time this may evolve to support much higher -possibly hypersonic- speeds with the addition of a NanoMembrane sheath surrounding the loop-way and allowing the conduits for the vehicles to contain a vacuum. Such a structure may be employed from the beginning with the construction of the core diffuser as a mean of reducing light attenuation along its length, just as with the evacuated optical conduits that would be used in the towers to bring light to the core.
With so many functional systems relying on those internal towers, it is likely that these would concentrate a great deal of activity and thus become a concentration of human residence. This coupled to the scale of the structures -as much as 50 kilometers up to the core of the habitat!- suggests that these would take on the nature of arcologies with a broad sloping series of Aquarius-style 'tectonic' terraces radiating out to the 'ground' plane of the habitat interior. The residential space design in these terraces might have many similarities to Aquarius style residence, though rather than the concrete materials of that early phase the predominant materials would be much lighter and much stronger diamondoid composites which could be even lighter still because their structures are functioning in tension between the opposing sides of the cylindrical hull, allowing for NanoRibbon cables to function as primary structural elements the buildings are 'suspended' from. These towers would be grouped in pairs, triplets, or quads around the circumference of the habitat, looking rather like the spokes of a wheel. Most of their height would be in lowered gravity environments with lesser practical use as residence and so these tower designs would likely feature broad bases and thin spires expanding to a node structure at the microgravity core akin to the 'urban tree' habitats of the Asgard phase.
We thus get an interesting vision for the environment of Heliopolis; a series of terraced urban zones dominated by arcology-like spires which blends into vast areas of naturalistic landscape interspersed with hobbit-like terrace residences and occasionally more visible public structures. Owing to the vast scale of the structure, both the sectional and orbital curves of the habitat's interior surface would be largely imperceptible. The perception would be that of a vast valley with walls rising into a hazy blue brightness running in a line overhead. Only at night would the 'tunnel' be made apparent by the star-like lights of residence windows and walkway lights. The view from the core would be much more tunnel-like. Owing to the use of holographic diffusers, the light from the core would be dimmed from the point-of-view at the core allowing inhabitants there to perceive the cylindrical landscape stretching off into a haze in either direction, and then transforming into a tunnel of stars at night. These core urban tree structures would have the same freedom of design as their Asgard counterparts and some may be more industrial or urban in nature while others may attempt a more naturalistic appearance and even attempt to create vast trees. Attempts to create a variety of landscapes and biomes are likely with the urban zones the likely demarcation between them. Even ocean zones might be a possibility, though likely quite shallow.
Initially, space in the Heliopolis settlement would come at a premium because the basic concept of the rotating habitat is inherently space-inefficient with such vast volumes unusable for anything more than containing air, hence the early establishment of a tradition of placing most habitable structures 'underground' instead of wasting surface space on free-standing structures that would be much better used for landscape and biome cultivation. But as the ease of fabrication for the habitat by virtue of advancing nanotechnology grows with its scale, a very low residential density may actually result -especially when one considers that increasingly great life spans and standards of living are often coupled to a decline in population growth. And so eventually an entire biome region or intervening urban zone might be home to a few hundred thousand people or less. And yet even in the most sparse of biome zones, a full urban level of convenience would be the norm with most homes featuring door-to-door PRT/PPT access. People would tend to congregate in the urban zones not for reasons of work but primarily for reasons of social interaction with the core urban trees dominated by recreational and entertainment activity -since permanent residence there may be unhealthy.
While originally started with the wound hull technology of Asgard, Heliopolis would likely evolve to incorporate NanoFoam composition long before it ever reaches full circle. The adoption of this technology would be interesting in itself, the NanoFoam structure essentially consuming the original structure in place with no change or interruption in any of its functions. The NanoFoam based Heliopolis would be essentially identical in organization but its structural elements would be transformed into integrated structures of the monolithic NanoFoam matrix. Hence the light collection and radiator systems once based on modular components would now become formed-in-place elements of a complex self-repairing hull system with a networked intelligence throughout. Similarly, the interior features and landscapes of the habitat would take on a more homogeneous sub-structure with land forms composed of a very light foam-like substructure rather than the space frame sub-structures previously used. The NanoFoam Heliopolis would become home to a composite artificial intelligence that overseas its vast ecology of distributed sensing, analysis, and control systems and which the inhabitants would be in constant dialogue with, requesting local changes to their personal spaces and the handling of a variety of work tasks. It would be quite akin to the transcendent macro-intelligences Savage envisioned would result from the critical mass of technology and population in the Solaria phase and would tend to be a common characteristic of all large habitats of any form based on NanoFoam composition.
The lifestyle of Heliopolis residents would tend to revolve -pun intended- around the crafting and cultivation of the biomes they create within the habitat -especially as nanotechnology advances to the point of making a great deal of human labor redundant. These biomes would not have a strictly functional purpose. Most agriculture would be performed 'underground' where it can be managed with the highest resource efficiency and with extensive use of automation. And as nanotechnology advances, many forms of food products would become either cultured or synthesized using nanotech systems. So the primary purpose of the biomes would be aesthetic, recreational, and related to the idea of expanding and preserving terrestrial life in space. By the time of Solaria, most of the common driving forces of daily life would become obsolete. Today daily life for most of our society revolves around the earning and preserving of wealth and property. For the already wealthy (wealthy enough that this wealth becomes largely self-perpetuating), life often revolves around either hedonistic distractions or the pursuit of political power and social status -immortality, after a fashion, through a name in the history books. Even for the corporate CEO, the job is really more about personal prestige than anything else -precious few among the upper class today are actually intelligent enough to do anything truly practical with hundreds of millions or billions of dollars in personal wealth... By the time of the solar civilization, most work would be replaced by automation, most forms of wealth would become irrelevant (money is primarily an abstraction of manual labor, which would become essentially 'price-less' in the Diamond Age, and while real estate may hold value, it may no longer be fungible), and most nations and governments as we know them today a fading memory or hollow anachronistic cultural artifacts like today's European monarchies. And so human culture would tend to become focused on aesthetic, creative, intellectual, sensual, and social pursuits. Experience -intellectual or sensual- would be the primary motivations to daily life and most 'jobs' would be voluntary pursuits in fields of art, craft, science, engineering, design, and entertainment with the reward not wealth but 'social credit' in the form of community social status and cultural significance. Fame, freedom of expression, knowledge, and experience will be the capital of the future. So one can easily imagine the inhabitants of Heliopolis -and most any other human habitat of the solar covoilization- coming to regard it as a vast art, science, and social project which they just happen to also live in.
SolarSnowflake and SolarRibbon:
These two habitats represent the logical conclusion to the concept of the MUOL and MUOF and they are grouped together here because the former has the potential to become the latter at any time. Though likely integrating some manned habitat structures of the kind developed in the Asgard phase, they would primarily be host to a settlement of artificial intelligences -perhaps non-sentient initially but eventually sentient. And so this represents the primary form of orbital habitat for the inorganic end of the transhumanist spectrum of future society.
The SolarSnowflake is a quite simple structure whose design would mimic that of Space Solar Power systems and which may actually originate for that purpose in a solar orbital location providing beamed power to more distant locations and projected-energy-powered spacecraft in other regions of the solar system as well as way-station or refinery services. It would consist of a planar space frame structure organized into four basic layers; a sun-facing 'energy layer' composed of solar panels or arrays of solar thermal collectors with power management systems behind them, a 'neural' layer composed of arrays of computer systems interspersed with optical communications trunks, an 'industrial layer' composed of MUOF style facilities surrounding a series of geometric bay openings, and a 'thermal layer' composed of surface-mount radiator panels. Along the edges of this layered structure would be power beaming and telecommunications arrays, docking and spacecraft service structures, as well as some optional EvoHab style habitat facilities and farming structures. These features may also be integrated into some large bays interspersed across the surface of the structure. A transit system integrated into the truss structure would be used to move cargo throughout the habitat. It would be similar to conventional PRT systems but based on mag-lev propulsion and use both container and pallet vehicles which, owing to the evacuated microgravity environment, could transition between various conduits supporting slow local speeds and hypersonic long distance trunks. These layered structures would be formed into large sections or 'tile' modules which are arrayed about the perimeter of the main structure as it grows in a fractal pattern, hence the name SolarSnowflake.
The SolarRibbon is what the SolarSnowflake would evolve into as it reaches its maximum practical radius -possibly some thousands of kilometers- and, like the Heliopolis colony, has the potential to encircle an entire solar orbit. Multiple SolarRibbons are a possibility as well, later ones being placed in orbits off the ecliptic to reduce their light blocking on the ecliptic. This kind of habitat is possible at the MUOF's level of technology and would see little change in its basic structural composition and organization until the advent of NanoFoam. With that the modular component structure would be replaced by a more monolithic and homogeneous self-fabricating structure which would replace most of its more specialized facilities with formed-in-place structures and use materials transport based mostly on fluid medium transport using peristaltic and magnetohydrodynamic propulsion. It would have a similar layered organization but likely be much thinner, its component factories replaced by local in-place nanofrabrication and its docking facilities used primarily as raw materials processing centers which 'digest' unrefined or recyclable materials to break them down into a kind of 'nanosoup' of packaged molecular components in a fluid medium that courses through the habitat like a bloodstream. This NanoFoam variation on the structure would probably lose its fractal 'snowflake' appearance, taking on the form of a simple monolithic disk or ovoid form.
To understand the lifestyle this habitat would offer, one needs to understand the basic lifestyle of the sentient AI since this would be essentially the same throughout all the habitats they employ -on Earth or in space- owing to the fact that it is independent of the architecture of the physical structures employed or the environments they are in. For the possible organic or augmented human inhabitant of this habitat, the mode of life offered would be identical to that of any large EvoHab or BioZome structure (which we will describe soon). But for the AI the habitat is essentially a support system for a vast supercomputer which hosts the Virtual Reality habitat they actually reside in. This habitat would be a complex multi-dimensional environment combining private spaces, public or privately managed but publicly accessible spaces, all variously integrated.
What do I mean by 'variously integrated'? All architecture in the VR habitat would be metaphor based, each virtual space built around a basic environmental model which defines its dimensional topology (usually either 'finite and bounded' or 'finite and unbounded') and characteristic simulated physics. Some metaphors are 'realistic' in that they attempt to simulate the sensual and physical characteristics of environments in the natural world or Actual Space, such as the normal terrestrial biomes and landscapes or existing urban environments. Others would be more fanciful or deliberately un-bounded by the conventions of normal physics. Imagine environments where gravity is a very local phenomenon. Buildings might have it but beyond their floor structures there is none so if you step off a terrace you float away and the building as a whole is simply suspended in space. These different environmental metaphors present different topologies which don't necessarily link-up. For instance, how does a 'space' designed to be like the deep sea which is dimensionally finite but unbounded connect to a 'space' that is an air-filled microgravity similarly finite and unbounded? Some environmental metaphors may link up because they have common topological characteristics, one can be contained by another, or they can otherwise share view space. For instance, one could make an 'island' or 'planet' with a particular kind of environment within an unbounded microgravity space. How spaces based on different metaphors integrate is most important in public spaces where an architectural continuity would be desired and so a meta-metaphor might be adopted for which all other public spaced connected them them must fit within. But others may have to be linked by 'portals' which bridge otherwise isolated metaphors that can't integrate and which might take any number of simple or fanciful forms. Private and/or non-connected spaces would, of course, be accessible only by a kind of virtual teleportation or though the use of on-demand portals which 'dial-up' different destinations.
There would also be some 'merged' environments where the Virtual Space overlaps Actual Space through the use of systems of telepresence in order to allow organic humans and AIs to freely and causally interact. In its earliest forms this may consist of simple rooms which use 'virtual window-wall' displays to make a location in Virtual Space seem adjacent to a location in Actual Space by communicating the window view two-way. Or it may take the form of 'virtual arenas' or 'viewquariums' where an enclosure of virtual window wall displays -eventually evolving to be holographic- surround a location in Actual Space making it appear like a kind of stage from the Virtual Space POV or a cylindrical array of such displays which create a stage-like space from the POV of Actual Space.
A more advanced form of merged space would be based on the organic human use of 'casual' VR telepresence devices such as eye-glass or contact lens displays and wearable cell phones integrated by WiFi and using an advanced form of GPS tracking. Discussed by both SciFi writers (such as Vernor Vinge) and computer technology futurists in recent years, this approach to merging spaces would model large areas of the organic human habitat for representation in the Virtual Space while adding to its structures virtual 'augmentation' that enhances or disguises the appearance and features of the Actual Space structures from the POV of the Virtual Space. Using those simple telepresence devices, the organic human being would view a combination of both the Actual Space and its VR enhancements while being able to view and interact with virtual objects and AIs that would be invisible to those not wearing those VR devices. Meanwhile, the AIs -as well as other people wearing those VR devices- would see their organic human counterparts with avatars much like their own. This sort of system would rely on interaction with organic human beings to expand the detail and area of the merged space by allowing the live 'scanning' of different locations with observation cameras or laser imaging systems and by 'painting in' the details according to what's viewed by the VR device wearer which, through its own built-in video cameras, records what the wearer sees in Actual Space then models it in real-time for the benefit of the inhabitants of Virtual Space. In this way the organic human can serve as a guide to the Actual Space by leading their AI counterparts to new areas which are scanned on-demand into the VR representation. The limitation of this system is that the Virtual Space can only visually and audially communicate with Actual Space, not physically/tactilely interact, while Actual Space can physically interact with objects in Virtual Space but without any tactile feedback. In the more distant future we may see the development of free-space holography which would allow for the full two-way spacial merging of Virtual and Actual Space within the confines of specific room areas but without physical interaction. Later some or full physical interaction may be possible with such systems, though limited by the environment physics of Actual Space.
And as if this all wasn't complicated enough, many inhabitants of the Virtual Space as well as temporary organic human visitors may be employing POV Filters. These would be image processing programs that modify the sensory input from Virtual Space to make it adopt a desired aesthetic effect according to the user's personal tastes. For instance, using these programs one person might paint his view of reality so it looks dark and Gothic, or another might paint it to seem more cheerful and colorful, while others might go for an abstract art inspired sense of reality.
One can see this is a very complex yet engaging environment likely to cultivate an equally complex culture. I have often likened the lifestyle of the AI to that of the fairies of European folklore, seeing as they would be effectively immortal, able to change their form, appearance, and environment spontaneously as a means of self-expression, and reside in a fluid mutable world crafted out of pure imagination that coexists invisibly beside the conventional world.
One constant problem with the habitat of Virtual Space, though, is latency. The underlying data processing architecture which supports the Virtual Space would be distributed, transparently networked, and homogeneous so an AI resident has no direct perception of it and the data comprising an individual AI entity doesn't necessarily have to reside in the same location as the environment he is interacting in or, for that matter, the other people he's communicating with. Indeed, an individual's personal software might be distributed in some parts quite widely over the Internet and backed up in many different places. AIs wouldn't actively 'think' about this any more than we organic humans think about our bodies' circulatory system or nerve network. That's all transparent to our perception. But in some situations the communications latency across the Internet would demand the localization of a person's software to overcome it. A person may become aware of this latency through artifacts appearing in the way they perceive feedback from their environment or other people -much as is noticed by the players of some on-line games today- or these artifacts may be precluded by background systems which sense or predict latency before it can be perceived and perform software transfers to more local systems automatically without the person even being aware of it.
On Earth, the future infrastructure of the Internet will likely support bandwidths and link redundancy of incredible magnitude. However, in space latency will be so great that the Virtual Space habitats located there would become completely disconnected temporally from the Virtual Spaces of Earth or other locations in space. Simultaneous communication is not possible at the speed of light over such distances and so public spaces could not integrate. People would have to transport their software whole to these distant places to interact with their local inhabitants and environments. Space travel for AIs would, of course, be quite easy by radio transmission and perceptually instantaneous. An AI space traveler need only use the same kinds of portals and teleportation programs they use to access any other disconnected region of Virtual Space. But across space this transit incurs a 'time lapse' for the data transfer of minutes to hours -eventually days, years, or decades as civilization reaches farther out into space- which the traveler would become aware of on arrival. This precludes any of the sort of direct interaction across these distant segments of the Virtual Space. Only asynchronous communications such as email would be possible. So these space habitats would be almost as disconnected from the terrestrial civilization as organic human space habitats would be, though with a time lapse within hours frequent commuting would not be especially inconvenient. And as the scale of the habitats in space grows -particularly at the SolarRibbon scale- it would be Earth that becomes the small far-flung outpost in comparative habitat scale.
While the aesthetic characteristics of Virtual Space would tend to be an open free-for-all, it is likely that space habitats like the SolarSnowflake would adopt public spaces with environmental metaphors thematically consistent with their location and make extensive use of 'virtual window' and 'merged space' environments based on exterior video cameras and other sensors. This suggests that a likely basic public environment metaphor for the SolarSnowflake and SolarRibbon habitat may be that of a kind of urban tree or urban ring in microgravity but devoid of any enclosing hull and in a virtual representation of the open space environment -a sort of abstract representation of the Actual Space structures hosting them.
The BioSphere -or Ukiyo habitat to use a more romantic name- is essentially the ultimate form of both the EvoHab and the Solarian habitat envisioned by Marshal Savage and is a specific advent of NanoFoam whose properties facilitate its very sophisticated form of hull system. It could begin as, and evolve from, an EvoHab structure associated with any orbital settlement but its maximum scale would be realized from those in Lagrange Point locations or solar orbits, likely associated with asteroid mining or materials transport waypoints.
The EvoHab concept was based on two key architectural concepts; the expandable modular component light transmitting hull structure and the core-truss-based urban tree habitat its contains. These structures are based on the use of modular component construction but the advent of NanoFoam would allow them to evolve into new forms based on its monolithic self-fabricating structure. The BioSphere hull would be a kind of very thick -though still quite thin relative to its enclosure scale- intelligent membrane which integrates a vast assortment of functions, serving as both pressurized shelter for a vast air-filled microgravity environment as well as the primary functional structure of the habitat. It would appear rather like the membrane bubbles envisioned by Marshal Savage, but would be perhaps a hundred meters thick with many functional layers. With sophisticated formed-in-place optics, the hull would be both light transmitting and image corrective/enhancing, appearing virtually invisible as a structure from a distance and creating an illusory Earth-like sky during daylight hours. This optical system would also integrate light filtering and energy accumulation elements such as photovoltaics which extract energy from unused portions of the solar spectrum and store the energy as packaged molecules within a 'nanosoup' fluid in a kind of internal circulatory system which also stores all the raw materials 'digested' by the hull and used for its maintenance. The hull would also integrate a series of fin-like radiators emerging from its shadowed side, though its efficiency at absorbing and storing the energy of the habitat's own latent heat would be quite high presenting a rather small IR signature. The hull's thickness would be its primary form of radiation shielding but it would also feature a series of magnetic loop and plasma emitters which would supplement this during solar flare activity and function as an attitude control thruster system based on solar wind deflection. Though seemingly quite rigid at the smaller scale of things, across its full area the hull would be a rather flexible structure -almost like a water-filled balloon- which uses a sophisticated mass and topology modeling system to assist its attitude control management. Docking station 'blisters' formed in strategic locations about the hull -mostly on its shadowed side- would provide booms for telecommunications arrays and the docking of spacecraft, bays for the nanofabrication of spacecraft and other large artifacts, as well as 'digester' facilities which convert or recycle materials delivered to the habitat for nanosoup storage. The whole hull area would also function a bit like a 'digester' to handle micrometeoroid impacts and their damage, healing itself and also capturing the debris for recycling! It might even employ temporary thickening of regions of its structure in anticipation of larger strikes or perhaps even create special shock absorbing capture zones to deliberately collect and digest streams of material launched in its direction. Permeating the entire hull would also be a computer 'neural' layer much like that of the NanoFoam version of the SolarSnowflake habitat, allowing it to host the same kind of AI habitat in combination with its organic human habit.
There are many similarities here to the hull system of the Heliopolis habitat, but because this is a microgravity habitat, it need not deal with the forces of a rigid rotating structure and thus its cross-section span could be vastly greater. Imagine a habitat enclosing a great air-filled microgravity space thousands of kilometers across! In effect, these could be great hollow planetoids. BioSphere's also have the option to evolve into ring structures completely encircling solar orbits and with a carrying capacity perhaps equivalent to thousands of Earths!
Within this vast space a new form of urban tree habitat would evolve along with a number of other structures. Devoid of any single central core truss, the BioSphere would deploy numerous clusters of urban tree structures suspended on nanofiber cables or employing active station-keeping based on the use of compressed air thrusters. These structures would also be NanoFoam based with their own individual circulatory systems supplemented by small tanker robots which communicate nanosoup in different concentrates between them and the hull -mostly for the purpose of communicating power packaged in chemical form. Each one the scale of a large town or small city, these clusters would likely employ a free-form organic design which freely integrates living plants through the use of a NanoFoam life support growth matrix which provides anchoring and nourishment for the plants akin to the gel based growing mediums sometimes used in plant culturing today. Personal residences would take the form of clusters of soft-walled chambers and netted terraces whose NanoFoam core structure grows them in place and provides all the other services and fixtures a normal home might require through formed-in-place fixtures such as furniture, lighting, ventilation, various appliances, and the like. And, of course, the structures would be changeable on-demand through a dialogue with the computer systems hosted in the NanoFoam neural matrix which could instruct the NanoFoam to restructure itself as desired.
Freed from the constrains of both gravity, low strength materials, and even the geometries of modular component systems, these NanoFoam urban trees would be free to employ non-euclidean architectural schemes we can scarcely visualize today -with only the architecture of the Virtual Space having more freedom. Some may be deliberately designed to emulate trees in roughly spherical form, borrowing on a design tradition perhaps established in the Asgard phase. Others may assume more enclosure-like forms, creating special interior open environments in the manner of a courtyard or atrium but volumetric.
In addition to these urban trees, there may be a great assortment of diverse structures of different functional and aesthetic purpose. Free-roaming sculpture-like structures may be created purely for their artistic value or to host small lounges and rooms as meeting places. Various tree structures created purely for the purpose of plant cultivation and to host similar meeting places are another possibility.
Arena spheres may be created as recreational venues, consisting of enclosures which are designed to host the various forms of microgravity recreation cultivated since the time of Asgard. Some may be designed as public theaters for new microgravity based forms of live performance.
Large free floating open rotating cylinder habitats may be created to allow for the cultivation of terrestrial biomes and provide housing for people preferring a gravity habitat. Much smaller than the Heliopolis habitat, they could nonetheless achieve scales approaching that of the classic space colonies, relative to the scale of the Biosphere as a whole, of course.
Whole asteroids may be enclosed within the BioSphere, hollowed out to create interior habitats while their exterior surface is cultivated with plant life. These structures would have no particular functional advantage over similar NanoFoam structures but could be the remnants of Shell Habitats which a BioSphere settlement originated from, retained for its historic or aesthetic value.
Large electrostatic fan and filter grids may be used, suspended from fixed anchors and serving to both clean and circulate the interior atmosphere.
Large water droplets or 'hydrospheres' may be created, shepherded by cages of surrounding electrostatic fan grids or contained in frame supported membrane enclosures. These would serve for both recreation and aesthetics, functioning like vast swimming pools and/or aquariums for hosting certain marine biomes and hosting some habitable structures within them.
Transportation in the BioSphere would be mostly derivatives of those developed to support travel within the EvoHab settlements of the past, with the anchor lines holding some structures used for CableWays and elevator-like capsule vehicles and individuals using wearable compressed air or nitrogen thrusters. But owing to the very large scale of the BioSphere, other more complex transportation may become necessary. The use of electric powered ducted fan vehicles and similarly propelled robots may become necessary for some work activities, though with so much of the population preferring their freedom to personally fly around few of these vehicles would be allowed. In the largest of BioSpheres magnetically propelled high speed shuttles much like those of the Heliopolis core shuttle might be created using anchored tensegrity structures to support their 'loopways' and NanoMembrane enclosures. Should a BioSphere evolve into a ring structure, this may take the form of a transit conduit akin to the core shuttle of the Heliopolis habitat.
The lifestyle offered by the BioSphere is probably the closest Actual Space can come to paralleling the lifestyle of the AI inhabitants of Virtual Space. As described previously, with the advent of robust nanotechnology the focus of daily life at the time of the solar civilization would be shifted radically from the pursuit of life support to the pursuit of experience through creative, intellectual, social, recreational, entertainment, and sensual activity. This would become consistent throughout the solar system as the Diamond Age progresses. However, the inhabitants of a BioSphere would, by default, qualify as an 'augmented' branch of humanity because their permanent habitation in a microgravity calls for a clinical means of compensating for continuous microgravity deterioration. Marshal Savage envisioned a fairly simple clinical solution to this problem but, in fact, it's proving to be a much more complex issue than previously thought and so it's not unlikely that this may ultimately require the use of colonies of medical nanomechanisms hosted continuously by the human body, constantly working to repair cellular damage and provide a kind of continuous medication created from the body's own molecular resources. Such a ubiquitous and intimate integration of this technology is also likely to lead to a host of other forms of cybernetic augmentation since they would come at little to no extra cost or inconvenience or have any impact on one's appearance. Thus one can anticipate the environment of the BioSphere to become a highly 'merged' habitat where a great deal of the features of the environment are virtual reality constructs perceived by the inhabitants because they have been 'wired' for continuous communication with the vast neural matrix dispersed among all the BioSphere's NanoFoam elements, This may lead to an organic human culture much more closely integrated to the culture and AI society of the Virtual Space than anywhere else. BioSphere inhabitants may be in a constant dialogue with systems, artifacts, and AI personalities which would be completely invisible to visitors lacking their necessary augmentation. They may frequently shift their degree of personal immersion into the Virtual Space according to their varying activity, freely moving between these two realms as readily as we move between rooms of a house. This may even call for some architectural accommodation in the form of comfortable 'pods' people can discreetly 'store' their body in while fully immersed in the Virtual Space. Indeed, one can imagine the peculiar scenario of people climbing into pods as a normal human being and then -from the POV of similarly augmented people in this merged environment- emerging as their virtual 'avatar' so they can carry on some activity specific to the Virtual Space. It is then a very short leap of the imagination to envision this leading to a rather steady exodus of human life from organic existence as people realize the lack of compromise in this shift and find their organic forms increasingly inconvenient with age -even if their basic nanotech augmentation may lead to average life spans in the hundreds of years.
Add to this that, as Savage has predicted, solar orbits may become the majority habitat for all life in the solar system and we can see that this remarkable and impossibly complex mode of life could very easily represent the general state of civilization by the time of Solaria.
The BioZome is ostensibly a NanoFoam based evolution of the surface habitats described in the section on Avalon but would not only become the dominant form of habitat in surface locations in space but also on Earth and any terraformed planets. It even represents the ultimate form of Aquarius marine colony, as NanoFoam ultimately comes to replace its inorganic material structure. BioZomes may also find use as a basic form of small scale orbital habitat, though they may not tend to stay that way for long in favor of the BioSphere form which they would have a natural tendency to evolve into as their resident populations increase.
A BioZome is essentially a contiguous mass of NanoFoam which has assumed a 'tectonic' (ie, landscape-like) macroform and serves host to a vast assortment of habitable spaces and sub-structures self-formed from its structural matrix. This is a concept first envisioned in the 1960s by megastructure visionary Rudolph Doernach who imagined the imminent invention of what he called an 'intelligent plastic' in the form of a self-replicating foam which he envisioned would form the basis of floating artificial islands which would be made habitable by instructing the foam to self-form various chambers in its simulated landscape to serve as homes and buildings. The BioZome would function much the same way except that its structure could form in place an infinite diversity of functional elements, giving it the means to adapt itself to and be used in virtually any environment. BioZomes would be able to intersperse with the landscape they are 'planted' in like an organism, forming habitable structures both above and below the landscape surface and obtaining directly from it energy and many raw materials for their self-fabrication through the use of vast webs of root-like structures.
In surface locations in space the BioZome would employ an assortment of subterranean structures while simultaneously engaging in a kind of 'terraforming' through the construction of BioSphere-like domes in sprawling clusters over the existing landscape inside which a naturalistic biome might be cultivated. As with the Heliopolis habitat, subterranean spaces would be preferred for most farming (which by this time may be reduced to industrial culturing or direct nanofabrication of foodstuffs) and industry so as to not squander surface landscape better used for the cultivation of biomes and the creation of surface residence structures. In harsher environments -as determined basically by radiation levels- the BioZome may employ primarily subterranean structures, excavating by 'nanodigestion' large chambers and using its root structures to fabricate-in-place a strong reinforcement structure within the natural strata to allow for even larger underground spaces than even lowered gravity environments might afford while also installing a hull structure able to compensate for (and extract energy from) latent geothermal heat. Used with larger asteroids and smaller planetoids, the entire surface and most, if not all, of the natural strata may be absorbed into the BioZome's structural matrix to create a massive settlement.
In orbital space, BioZomes would take the form of organic clusters of linked chambers -some featuring BioSphere style hulls- interspersed with smaller personal residence chamber clusters and with the whole complex adorned in petal-like solar and radiator arrays creating a rather plant-like appearance. These may be used as smaller scale planetary orbital facilities and may characterize the composition of the Geopolis Ring habitat as it too evolves to accommodate NanoFoam composition. It could also become the basis of Cyclic Shuttle spacecraft as well later Galactia interstellar spacecraft -these requiring a more rigid and dense structure than the BioSphere might afford.
On Earth and on terraformed planets, BioZomes would form the basis of arcologies and linear cities, their transportation links and utilities systems, and a vast renewable energy and materials recycling/processing infrastructure both above and below ground and dispersed across the seas. Arcologies may become the dominant mode of urban habitat on Earth thanks to a trend initiated by Aquarius and the compulsion for community efficiency driven by both dwindling fossil energy resources and a growing awareness of the environmental impact of simple habitat itself. NanoFoam would incrementally replace the original structural composition of these communities, linking them together into a vast intelligent structural matrix managing energy, materials, and space on a global scale while playing host to most of the planetary population. These terrestrial BioZomes would offer complete architectural freedom but with all of the human habitat linked together -even if it is only subterranean communications and materials transport links invisible at the surface. Much of the Earth's subterranean space may play host to a vast NanoFoam structure called a RhiZome which serves like a vast neural matrix for the planet and its organic and inorganic inhabitants. Only sea and aireal habitats may be physically disconnected from the dispersed terrestrial BioZome, though still based on BioZome structures of their own linked by telecommunications.
BioZomes may ultimately represent the essential means by which civilization colonizes the rest of the galaxy. Any natural body in the galaxy could be colonized by the simple deposition of a small NanoFoam payload which would then be instructed to begin structuring itself to scavenge its local environment for materials and energy and growing a habitat to any scale. Vast settlements could thus be created long before a single human being arrives to live in them.
While the above descriptions seem to imply a habitat more like a cybernetic version of The Blob than anything we might call 'home' today, the NanoFoam would actually be quite effective at disguising itself through the crafting of surface structures and finishes indistinguishable from natural materials and would be capable of assuming an infinite variety of design forms. Since it could also serve host to living plants as well, it could be made quite indistinguishable from even natural landscape. The only effective difference between conventional materials and NanoFoam would be its high core strength and ones ability to digitally communicate with it to tell it what to form itself into. Earth BioZomes in particular would likely most often seek to mimic traditional styles of architecture and in some cases the only hint that community habitats are part of a BioZome's contiguous structural matrix would be the way blister-like structures form around portions of buildings when the NanoFoam is reforming or adding to them. In space, the BioZome nature of the habitat would be made more apparent by its use of very different macrostructures, such as the clusters of BioSphere-like domes enclosing surface habitats or volumetric clustering of organic spaces in an orbital habitat. But at the human scale, the NanoFoam structure might still emulate any variety of natural materials for sake of comfort and aesthetics -or for that matter employ them in ways that might be impossible for the natural materials. For instance, one can imagine endless seamless structures of carved marble, wood, or fabric.
As with all habitats of the later Diamond Age, the BioZome would tend to produce a leisure-dominant culture due to NanoFoam's ability to effectively automate any form of work and provide inhabitants with life-support at no cost. And like the BioSphere, the structural matrix of the BioZome is itself also a neural matrix hosting a vast Virtual Space that could be home to a large community of AIs as well as hosting innumerable communications and information services for the organic human population. This could easily host a 'merged' environment akin to that of the BioSphere, though surface inhabitants may have less incentive to adopt the same degree of cybernetic augmentation their orbital space dwelling counterparts would since -thanks to a gravity environment- they may have less or no need for the kind of medical nanosystems aids to life support. Still, it's not unlikely for the BioZome lifestyle to go very much the same way as the BioSphere lifestyle as cultural integration of cybernetic augmentation progresses.
The RhiZome is the natural body surface equivalent of the Solar Snowflake habitat, intended primarily as a means of remotely exploiting the natural resources of planets and moons while also serving as a settlement primarily for sentient AI inhabitants. The habitat gets its name from the biology term 'rhizome' which refers to the biome for microscopic life that exists amidst the roots of plants in natural soil. In nature, the RhiZome would be quite similar, consisting of a NanoFoam matrix that had been adapted to intersperse itself throughout the subterranean regions of a planet, moon, or asteroid producing rather plant-like structures above the surface to function as solar and communications arrays or atmospheric processors, a vast network of subterranean root structures to tap materials resources and latent geothermal heat, and a great circulatory system for NanoSoup to store and communicate materials and energy coupled to optical data communications trunks. Small BioZome-like structures may also be included to host organic human life, to cultivate biomes for scientific purposes, or to create spaces for the fabrication of vehicles and other artifacts while subterranean mag-lev vehicles may be used to quickly transport passengers and goods around -though the need for that would be rare and probably associated with hosting organic human residents. RhiZomes may average no more than a hundred meters in thickness yet expand to such vast areas that they completely encompass a planet like a kind of gigantic brain and circulatory system.
RhiZomes may be established on every major body in the solar system by the time of Solaria and even Earth itself may host them. Even without the advent of sentient AI, a RhiZome-like structure makes sense as the logical basis of a late Diamond Age infrastructure. It is, essentially, the ultimate form of Internet matching computing and communications to an energy and resource network rooted in nanotechnology. Some RhiZomes may originate as teleoperated settlements of the Avalon phase which simply never evolved to become organic human settlements or which were abandoned for that purpose or in some way stalled in their development -not an unlikely possibility considering the tenuous economics surface settlements will originally face. These pre-NanoFoam RhiZome habitats would be largely identical to the excavated teleoperated settlements except for their focus on the creation of vast subterranean data processing banks as opposed to pressurized habitat structures and a possible greater focus on the development of geothermal energy systems that would reduce reliance on above-surface structures.
RhiZomes could also become the basis of comprehensive terraforming programs by using their globally dispersed infrastructure to establish vast systems for the transformation of surface environment. A fully developed RhiZome would be in the unique position to process and manage the energy and material resources of a planet wholistically with global coordination as if it had become a kind of active intelligence for that planet. It can thus freely redistribute resources globally, simultaneously 'grow' large sophisticated machines all over a globe, and engage in complete physical restructuring of a planetary surface landscape. One can easily envision an AI community engaging in such activity for much the same reasons that inhabitants of a Heliopolis colony cultivate their own diversity of biomes; simply for the aesthetic and scientific value of cultivating a vast garden.
The lifestyle offered by the RhiZome would be essentially identical to that described the SolarSnowflake and every other structure that hosts a Virtual Space habitat except for any organic human residents who might also reside in a RhiZome settlement would live in smaller surface-style BioZome habitat structures integrated into the RhiZome. Because RhiZomes would have so much materials at-hand while not being concerned with the limitations of transport within a gravity well, they would have the ability to grow at a much greater pace than their orbital counterparts and so may actually gain some preference in their development with the AI community.
As we can see, the solar civilization could offer a large and interesting diversity of habitats while realizing the super-community envisioned by Marshal Savage. Toward the end of his description of the Solaria phase, Savage posed the interesting notion of a society so vast in number and so well integrated by communications and computing technology that it spontaneously produced a series of collective macro-intelligences inhabiting the networks of the civilization's infrastructure and functioning rather like demigods. He was, however, rather abstract about the nature of the technology that might realize something like this. My vision of Solaria suggests a very specific technology where this might actually be a possibility; NanoFoam. As we've seen in this sampling of habitats, NanoFoam or something akin to it will become the fundamental material composition of the civilization, hosting both organic and inorganic life together, merging their habitats, and linking it all together in a single information network interspersed within the material matrix of every artifact, structure, and habitat the civilization creates. This network could thus conceivably realize the kind of macro-intelligences Savage envisioned as a kind of semi-sentient intelligence embodied by the habitats we reside in. Savage commented that one would not be able to invite these intelligences home to dinner but, in fact, maybe we could since people -be they organic or AI- would be in constant dialogue with the systems of their habitat which might be represented by a kind of AI assistant program for the sake of convenient user-interfacing which we would simply talk to in the manner of the ship's computer in Star Trek. That computer embodied the 'personality' of a single starship but here we have the possibly of an entire civilization and the sum total of its collective knowledge being similarly embodied. It would be as though the individual and the collective universe could literally engage in casual conversation!