Creating Habitable Planetary Environments

Terraforming replicator globules
Image from Anders Sandberg
A Stanleymiller Biogenesis ecoforming cluster about to seed the Mars-type planet New-Zeia (formerly YTS 3261-2610419-iv) with bionanotech replicator globules; Sagittarius Sector, Outer Volumes, 10192. Stanleymiller Biogenesis is one of a number of terraforming corporations opening up the sector's periphery to habitation.

Far from planet-dwelling being abandoned, I adhere to the vision of planets being the luxury real estate of the far future - natural homes for life where life-support is almost or completely freed from the need for technological subsidy. Thus terraforming might not just have a crucial part to play in the future of the Solar System, but more importantly, in the unfolding drama of life in the Universe as a whole. Martyn J. Fogg, Terraforming (early Information Era)


Terraforming is often used as a blanket term for all methods of making a world more suitable for life. Strictly speaking it can be divided into ecopoiesis, enabling the formation of a self-sustaining biosphere, and full terraforming, the transformation of a world into an environment where bionts can live unprotected. Terraformation has also been practiced by various species of alien xenosophont, resulting in many different kinds of environment suited to their varied biochemistries. Examples include the Thiogen worlds and the Halogen worlds.

An alternate strategy to terraformation is the alteration of the physical characteristics of colonists in order to tolerate or thrive in the environment of a world. Clades which have been radically changed in this way are collectively known as 'tweaks', and the process of adaptation is known as Pantropy. On many worlds both pantropy and terraformation processes are utilised, so that the planet is altered to some extent, and the colonists are modified to thrive in the new conditions.

Closely related to terraforming is geoengineering, including various technologies for controlling the climate, biosphere, hydrosphere or lithosphere and other planetary systems.

Already from the start there were two different philosophies of terraforming. The ecocentric approach sought to use natural means to the greatest extent, ideally nudging a planet into a life-sustaining state with a minimal effort and later keeping it there with no need for technological intervention. The technocentric approach instead would use whatever technology was available to make the world habitable, and did not shy away from installing technological systems to sustain the biosphere. The ecocentrics regarded this as both inherently unstable - what if culture did not sustain the infrastructure needed to keep the planet livable? - and inelegant, possibly even unethical. The technocentrics regarded the ecocentric view as too slow, too mild and likely unable to provide a truly human-habitable biosphere. The ecocentric and technocentric philosophies have remained within the terraforming community for millennia, producing a vast discourse on the ethics, aesthetics, economy and methods of terraforming.


The first terraforming project was Mars during the interplanetary era. Although relatively few coordinated efforts were done, the consensus on what was needed was fairly strong among the involved corporations and colonists, and they nearly independently cooperated at the task: heating up the atmosphere with greenhouse gases, releasing carbon dioxide and water from the regolith, finding ways of introducing plants to create a breathable dense atmosphere, increasing solar influx and so on. In the second and third century AT the first biotech and nanotech replicators were introduced: genetically modified plants producing fluorocarbons and oxygen, as well as nanotechnological factories digging into the regolith for nitrogen and producing gases protecting against UV radiation. Solar reflectors were aimed at the poles and later the rest of the planet, and occasional comets were re-directed to hit the planet to replenish the volatile supply. This terraforming was a mixed ecocentric/technocentric approach, well supported by a large majority of the settlers. It was sometimes violently decried by a minority of essentialist 'reds' wanting to keep Mars pristine, but they remained marginal and mainly earthbound. In 233 the first recorded rainfall fell on the planet, and by 350 Mars had become so earthlike that specially tweaked humans could survive on the surface. It would never have become exactly like Earth, with its large saline boreal ocean, thin and dry air and extensive genemodded martian pine forests, but it showed clear habitation potential. Despite the serious setbacks during the Technocalypse, Mars was a proof of concept that terraforming could work.

comet impact mars
Image from Anders Sandberg
Comet impact 21600123-5 striking Hellas Planitia, the designated main target area on the southern hemisphere of Mars. The constant stream of ice packages from the outer system striking Mars at regular intervals did not cause much problems for near-planet traffic control and did in fact keep the Mars alliances well supplied with volatiles for their orbital habitats. Only a handful of accidents did occur, the most serious when 22070712-1 hit a settlement in the Terra Tyrrhena after an unexpected very strong outgassing a few minutes before impact.

Geoengineering had become necessary in the meantime on Earth, where massive climate disasters threatened billions. Methods for cooling the planet using dust launched into the stratosphere, local heating through space mirrors, weather control and the use of nanotechnological carbon sinks had become commonplace. In a similar fashion the space colonies led to the development of ecodesign, the deliberate construction of stable and productive ecosystems.

There were many discussions about terraforming Venus, the Moon or even the Galilean satellites of Jupiter during the interplanetary era, but no serious effort. Any such project would have had an exorbitant cost, and in many cases political issues made it impossible. The Mars project was highly dependent on outer system water, and the Mars powers had to constantly deal with the Genetekkers to continue their effort. The Orbital Alliance was on far less cordial terms with the outer system and would hence never be able to get enough volatiles to improve the Moon. Meanwhile, some Io Genetekker factions were attempting ecopoiesis using radiation-resistant thiophilic and thermophilic bacteria living in geothermal vents, supplied with ice from Europa, but the project never gained momentum.

The next world where terraforming was attempted was Nova Terra in the Tau Ceti system. Although a much more suitable target than Mars in many geoengineering respects, a combination of lack of experience, an inefficient ecocentric approach (Charlie biobugs plus comet redirection) and unstable politics made the initial terraforming fail. The planet was properly terraformed first during the Federation era.

Several other early terraforming projects failed, some spectacularly. Zeta Tucanae II suffered an uncontrolled massive cometary bombardment as the subturing mining systems in the Kuiper belt launched too many comets at the planet. After the bombardment had ended and algae had re-emerged among the craters, the planet was in fact successfully life-bearing, but none of the initial colonists survived. Penglai and Pacifica were successfully terraformed but it took much longer than expected. The terraformation of Arcadia resulted in a cycle of warm and cool periods that made colonisation challenging, while Zarathustra turned out to be the most successful case of terraforming in this period, largely because it was almost perfect for terraforming from the start.

The First Federation Megacorps

It was during the First Federation period that terraforming went from expensive gambling to industry. The lessons learned from restoring the biospheres of Earth and Mars, together with the new data from the colonies and the help from ecotect hyperturings made terraforming a viable option. The new methods developed as new systems were colonised and the terraforming corporations grew to prominence. Since they could earn rents from their planets in perpetuity, terraforming stock became the greatest and safest investment method for over 3000 years, and were the basis of the emergence of many major houses.

At first, terraforming took centuries to complete, but after the end of the Federation era extensive use of synanotechnology and megascale engineering such as mirror arrays, orbital rings, sunshades, solettas and magshields brought down the average time of terraforming to decades. Using even more technocentric approaches the scale could be reduced further in many cases, down to mere years for very Earth-like planets.

The record was the 4033 terraforming of Golden Egg (today Gozany) by the Solar Dominion. As a demonstration of power and skill, a massive terraforming effort turned the venusian planet into a biological paradise over the span of just 10 months. It relied on having hyperturing-directed replicators turn a local asteroid belt into a partial Dyson shell, disassembling two ice moons in the outer system, massive nanotechnological remodelling of the planetary surface combined with element synthesis and an array of orbital rings for cooling. Although Golden Egg became a very successful biosphere, the sheer expense of this ultra-technocentric approach make further projects of this kind unlikely.

After the era of early interstellar expansion terraforming grew increasingly selective. Due to the expense and the demonstrated problems of attempting to terraform suboptimal worlds, and the vast selection of potential colonisation targets, consolidation era terraforming mainly aimed for easily terraformable worlds. In the following millennia long-range colonisation has been of this kind, while secondary colonisation of systems near previously settled 'ideal' systems often involve terraforming less easy worlds. This has resulted in the typical cluster structure of interstellar expansion: a central system with a terraformed world, surrounded by a number of younger secondary colonies with some terraforming, in turn surrounded by tertiary and younger colonies.

Many terraforming corporations, suggesting that it was better to meet the planets halfway by adapting colonists to the conditions but fixing the worst drawbacks with terraforming, began to incorporate pantropy and radical tweaking into their strategies during the First Federation era. These corporations with their mixed approach could achieve habitability much faster than the more technocentric corporations, but their worlds were only suitable for adapted modosophonts.
Worlds that were too cool, too hot, or which had elevated levels of various toxic elements or compounds were the result of these endeavours; many part-terraformed worlds had high levels of CO2 or radiation, for example, which required the colonists to be radically tweaked. This meant that visitors to such worlds would need advanced medical procedures before arrival, or they would need to wear suitable envirosuits at all times.

Terraformation megacorps that adopted such strategies could get a much faster return on investment, since they could deliver habitable worlds much faster and with less expenditure; but the hidden costs of such worlds were considerable, especially for unmodified visitors. Each of these worlds required a specially adapted ecosphere to suit the non-standard environment, making ecopoiesis a significant part of the process. The mixed-approach megacorps therefore became known as specialists in ecopoesis. A large fraction, over 76% of the ecopoiesis corporations eventually joined into the growing conglomerate Birnam Ecotech. Birnam had made ecopoiesis and bioism to its corporate religion, refining them not just ideologically but also practically into an art of terraforming sometimes called birnamism. As the corporation joined the Conver Ambi, ecopoiesis became the ideological norm of the empire. This in turn made ecopoiesis a political statement, and many of the other empires deliberately moved in a technocentric direction. As the Conver Ambi was destroyed in the Second Empires War much of the strength of the ecopoiesis movement vanished. It was restored by the Softbot Coordinator Systems clade of superiors, which developed into the Softbot Cathedrals. After their destruction the "Great Green Tradition" was continued by the Negentropy Alliance. The economy of energy and work and reverence for the natural state emphasized by ecopoiesis fitted their ideology perfectly.

As an opposing strand the technocentric approach was mainly developed in the Solar Dominion and the MPA. The MPA excelled in megascale engineering and many dramatic and creative forms of terraforming - everything from building worldhouses to attempts to make toroidal worlds. The emphasis was mainly on concepts, ideally every world should be totally unique and unusual in one way or another. The Solar Dominion was far more conventional, but instead saw terraforming as a political tool. By the creation of terraforming orders linked to the Divine Order such as the Disciples of St. Fogg and the 268 Planetologists they both gained living space, gave the Divine Order rents and ecological control over formally independent worlds and also could determine what kinds of habitats (and hence clades) to encourage.

A trademark of the Dominion is the "solarian suns", or "sol-sols". Planets with too slow rotation are hard to speed up, but the Dominion has mastered the use of a massive soletta in polar orbit around the planet combined with a solar shade at L1 to give the planet an arbitrary artificial day. Near the poles the climate is equatorial, as the reflected sunlight passes overhead every day. At the equator there is instead a short year as the planet turns, shifting between polar days and nights with a period equal to half the rotation period. The result is often a much gentler climate than found on any natural world.

Sunshade technology Kirch
Image from Anders Sandberg
Kirch, a former venusian world in the outer Solar Dominion is in the final stages of terraforming by the Disciples of St. Fogg. A solar shade is located outside the picture several million kilometres to the left, keeping the planet in the shadow-cone. Above the planet the main soletta orbits, reflecting sunlight onto the planet. It is surrounded by control solar sails and maintenance stations. Around the moon Frial the local garden can be seen, currently in the process of growing the seed biosphere of the planet. Frial was used as a source of reducing material to reduce the atmosphere of Kirch; the structure currently acting as garden produced energy to drive several thousand mass drivers launching iron, calcium and magnesium dust at the planet.
The To'ul'hs early began their own projects to "touhlform" venusian worlds. It turned out that this was fairly easy compared to terraforming them, although some conflicts over planets suitable to both ensued. Toulhforming mainly aims at setting up the correct atmosphere biology and adding requisite amounts of needed elements and chemicals. Various To'ul'h clades have developed their own preferences, and in the MPA and Keter dominion many radically different To'ul'h worlds now exist.

Today terraforming has been a mature discipline for many millennia, and most terraforming is performed using a multi-decade timescale for cost reasons. Due to the extreme expense and long-term investment, many clades do not employ terraforming at all and use habitat construction or paraterraforming instead. However, given the relative scarcity of habitable worlds and the strong demand for a "natural" environment from many clades, terraforming is still a very lucrative market.

Candidate Worlds

Several kinds of worlds can be terraformed:

The easiest target are Earth-like but lifeless worlds, similar to pre-biotic Earth or young Mars or Venus. The goal is just to set up an oxidising atmosphere and thriving biosphere. This can usually be achieved fairly simply using nanotechnology and extensive ecotecture. Converters are set up to produce oxygen (usually replicating solar-powered nanomachines or macrotechnology). Algae and later higher animals are seeded across the surface, and slowly the planet is turned into a biosphere.

The second easiest category is perhaps surprisingly cytherian worlds and especially so-called wet greenhouses where much water is still retained in the atmosphere. Here the task is to remove the thick and hot atmosphere, cool down the surface and set up a biosphere. Several methods exist. Some worlds are amenable to "green sky" conversion by floating algae or nanomachines. Others can be handled by planetary chimneys and atmosphere sequestration underground. Solar shades are placed in front of the planet, allowing it to cool off. Reducing agents are added to absorb excess carbon dioxide. Needless to say, venusian worlds are best amenable for the technocentric approach.

Martian worlds are more cumbersome, as they often have too little volatiles to work with. Either they have to be released from underground storage, produced in place or supplied externally. The challenge is to heat up the planet and make the atmosphere dense so that liquid water can exist, as well as get a sufficient greenhouse effect going to keep the temperature up. Usually this is done by releasing stored volatiles and by dropping large amounts of ice from asteroids or comets onto the planet. It is often possible to achieve ecopoiesis on martian worlds using more ecocentric approaches, but it takes time.

It is possible to give even moon-like worlds a dense atmosphere with some work, although this is seldom economical. Gas giant moons are sometimes warm enough to be usefully terraformed, although commonly solettas are needed to provide them with light due to tidal locking. Heavy rock moons like the Earth's moon can retain an atmosphere over tens of millennia if supplied with enough volatiles, although it will constantly seep away and they often have a troublesome length of the days.

Tidally locked worlds such as Twilight were difficult to terraform in the early days; the constant sunlight on the hot side and the cold on the dark side required the terraformers to add extra amounts of volatiles to keep the hydrological cycle running and often massive landscape re-engineering to promote ice to move towards the terminator to melt. Today sunshades and mirror arrays, or advanced Weather Machines are often used on desirable worlds with tidal locks. Weather machines are useful for many purposes- small, floating bubbles fitted with adjustable mirrors, they can cool a hot planet or heat a cool one, and transport heat and light to the dark side of a world.

Target solar systems are usually systems that are fairly young, since it has been found that it is more likely that younger planets have sufficiently active geological cycles that can sustain an ecosphere. Without it many otherwise suitable worlds will not be able to return carbon dioxide from carbonate sediments into the atmosphere without artificial help ("assisted breathing" as some terraformers call it). A minor drawback with young planetary systems is that they often are still quite meteor rich, but modern defensive systems can usually handle it. In fact, the large number of comets is beneficial in getting enough water many terraforming projects. Without extensive comets or Kuiper belt objects it is common to use icy gas giant moons, but the energy costs are much heavier.

Daffy being terraformed
Image from Anders Sandberg
Psi Serpentis V in the middle stages of being terraformed by Lander Geotech (approximately 2049). The formerly hot greenhouse world has been cooled using solar shades and the atmosphere thinned by Sagan algae. A relative simple terraforming target, although the high level of nitrogen in the geosphere and the occasional flares of the star made it somewhat hard to balance ecologically.


The main issues that have to be dealt with in terraforming are achieving a habitable temperature, atmospheric composition, pressure, a hydrosphere, lack of hazardous radiation and meteor impacts as well as setting up a stable biosphere. Usually all these problems are interlinked: for example Mars lacked much atmosphere, which kept it cold and dry and allowed UV rays and meteors to hit the surface. By adding extra solar power, making the atmosphere denser and adding more greenhouse gases, frozen carbon dioxide and water began to thaw, adding to the atmosphere. This made it even denser, allowing further thawing supported by Neumann replicators and neogen plants. Eventually a break-even point was reached where Mars "popped" into a new warmer and wetter equilibrium (helped by several major ice meteors). The eventual addition of a Lagrange Magshield ensured that the new conditions would be protected against the solar wind; similar magshields are commonplace in the Current Era throughout the Terragen Sphere.

Transports of large amounts of material are expensive, and shipping water or atmosphere constituents to a planet lacking in them is extremely expensive unless it can be automated and the raw materials produced cheaply at a local source. Often Kuiper objects are used; they are towed inwards, cut up into manageable chunks and allowed to impact a dry to release their ice. Care has to be taken with course control, as the space around a world being terraformed is often very busy.

Removing unwanted atmosphere is harder. It can be blown off by meteor impacts, but this is impractical. Instead it can be converted into a solid form and sequestered underground, or scooped off using solar-powered scoopships. Sequestration consists of converting excess carbon dioxide with nanotechnology into diamondoid that can be buried (or exported) and oxygen; similar schemes can be used to free atmospheres of other gases. Planetary chimneys are megastructures extending up to orbital ring systems, acting as enormous mass drivers heating and pumping away atmosphere into space. The method is regarded as inelegant and wasteful, and requires enormous energy supplies (usually matter-energy conversion or massive partial Dyson swarms).

Temperature can be up-regulated by adding greenhouse gases such as freon, carbon dioxide or water vapour, making the surface darker by planting dark plants or spreading dark dust, or adding solar reflectors ("solettas") in orbit to heat up the planet locally or globally. Similarly, it can be down-regulated by adding reflective dust in the stratosphere, increasing the surface albedo or by placing solar shades in the Sun-Planet L1 point (usually called "homebase" by many terraformers, as this point is often the headquarters of the effort and the locus of many megaengineering systems).

Solettas exist in a variety of forms, from the small lunettes merely adding light to otherwise dark regions, over the agrisolettas improving agriculture or biological production to the major climate control solettas that heat up entire planets. Most are simply extremely thin films placed in a statite position above one of the poles of the planet, reflecting sunlight down on the surface. In terraforming gas giant moons large frameworks are placed in the L4 and L5 positions around the moon and adjustable reflectors reflect extra sunlight onto the planet.

Biological bootstrapping often is done as the other terraforming occurs. First hardy, strongly modified organisms are implanted to help the terraforming by binding loose soil, dust, darken surfaces or convert carbon dioxide into more complex chemicals (a popular scheme with wet greenhouse worlds is the so-called Sagan green atmosphere, where floating algae in the atmosphere are used to decrease the greenhouse gases and shade the planet). Later a succession of species is introduced, bootstrapping ecosystems of increasing complexity and productivity. Eventually the climax ecosystem is seeded, hopefully producing a stable biosphere. It is common to build a orbital "garden" in the vicinity of the planet to act as a greenhouse and breeding habitat for plants and animals to be transported downplanet.

A different approach, pseudoterraforming or paraterraforming, is often used. It does not attempt to change the entire planet, but just set up a livable environment within an enclosed region. As these regions grow, they can come to encompass a sizeable fraction of the planet or the entire world, such as Bolobo and Secharia in the Inner Sphere; such worlds are very common throughout the civilised galaxy. These "worldhouses" consist of transparent roofing held up by multi-kilometre pillars. Due to their height clouds can form, and as they are extended laterally temperature differences (often carefully regulated by partitions, of course) create winds and weather. In the largest worldhouses entire climates develop. Naturally, such structures require constant maintenance and will fail if not repaired. One early pioneer in the practice of paraterraforming was Benedita Bluesky DaCosta, who travelled all over the Inner Sphere and Middle Regions creating her distinctive blue worldhouses.


It has been noted that the ships and installations of Disciples of St Fogg are occasionally attacked by the Birchian Brotherhood, who consider the DOSF "slackers and heretics."

This is less serious than the strife between the BB and the Gaian Church of the prophet McKay. Far from being heretics, the Foggists actually occupy the sane middle ground between the two.

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Appears in Topics
Development Notes
Text by Anders Sandberg
additional material by Steve Bowers
Initially published on 28 January 2001.