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by Kjetil Gjerde, M.Sc. Autumn 2000 from TheTerraformingInformationPages Website
This research deals with terraforming - the process of transforming the climate of a planet until it is acceptable for higher order terrestrial life.
I will consider the development of this research - from science fiction till today where the research is on the threshold of getting accepted as serious.
The difficulty and extent of the process is sharply defined by the present condition of the planet. The contemporary research considers mainly terraforming the planet Mars – due to the simple reason that Mars represents the basis which is closest to earth, and therefore is the easiest planet to terraform with the current technology. In this report the historical development of this research, which began as pure science fiction, is discussed.
Furthermore, a short introduction is given of the currently most reliable plan of how to terraform Mars based on technology of today. To get acceptance in a serious and established scientific research environment is not simple when the ideas originate from science fiction literature. This is a new and exciting area of research, with unthought-of possibilities.
Those who dare to lay hold of this, may have a great possibility of becoming pioneers within the area. Or will history judge the task as being impossible to solve – as was the case for the medieval alchemists. In that case the researchers which were bold enough to do research in this field will disappear into a false trail within applied science research. The growth of such a new field of research is a little bit different from the growth of new paradigms in basic (scientific) research in not having to leave an old paradigm.
However, different models arise within the research field, which do belong to different paradigms. As new knowledge becomes available, the different models and theories will be verified or falsified, in the latter case allowing new models to develop.
This process often leads to internal
struggle in the research environment.
David Hume expressed this as follows (A treatise of human nature 1740):
Schopenhauer meant that it was not the intellect we discussed with, but the will. It is not easy then to conduct meaningful discussions between people from different paradigms.
The strategic and tactical elements overcome rationality. Kant declared once that one must suspend knowledge in order to allow faith. In order to understand a theory and with that be able to believe in it, one must have a lively perception of it.
And that is not always simple if one
initially is hostile towards it.
Heinlein published the first science fiction book that was about terraforming. More well-known is perhaps Arthur C. Clarke who wrote a novel that included the terraforming of Mars in 1951 (The Sands of Mars).
But in this time everything concerning terraforming was still considered as pure science fiction, and not as a serious research – something that it at this stage neither was. However, it is often the case that science fiction shapes the minds of young people set to become the researchers of the next generation. The individual that perhaps has meant most in gaining approval of terraforming as serious research is possibly Carl Sagan.
Several of his articles from the early 1960’s dealt with the possibility of terraforming Venus and the introduction of microbiologically life. His doctoral thesis also dealt with Venus and presented an explanation to the elevated temperatures on Venus as certain observations indicated. This thesis treated the greenhouse effect – something that is quite important also in the contemporary serious research on terraforming.
Sagan’s article was published in 1961 at the same time as the space probe (soviet) was on its way to Venus in order to do the first ever in situ measurements. This article is the first scientific article referring to terraforming, even though the concept itself is omitted. Principally the article discusses the climate and the atmosphere one Venus, and ends with a philosophy about how we can precipitate the CO2 currently in the atmosphere, by the use of blue green algae.
Through this the temperature should
decrease, and Venus should end up with a far less hostile
environment.
Then speculations on how to travel to the moon or journeys underneath the ocean were common. Science fiction in its time, but something that was conceivable with the technology of those days, or at least something that could be reasonably achieved in a foreseeable future. New thoughts and science fiction have a tendency to represent something ahead of the actual technology, but not something unimaginable in a nearby future. Then a technological revolution when it concerns exploration of space took place in the 50’s and the 60’s.
We were on our way to the moon. We
launched space probes to explore other planets. It happened in its
time, and made possible steps forward in the world of imagination.
It was now possible to consider the possibilities of terraforming.
According to his model of terraforming Venus, the planet would end up covered in a several hundred-meter thick dust layer of precipitated carbon, given that his model would work in the first place. Such a dust layer could not be consistent with terraforming. New knowledge about the conditions of Venus has made the problems of terraforming the planet with present or near future technology so big, that research is increasingly focusing on the terraforming of Mars.
This terraforming is something we can imagine as a natural extension of the technology and knowledge of today. We can achieve a lively perception of the feasibility of the project. The theory of the models is perceived, at least by the supporters, as likely – and therefore credible. However, some basic assumptions about the present condition of Mars are made.
Even if different methods have been
proposed and modified for the terraforming of Mars, the main model
seems to have survived the acquisition of new knowledge. This model
can now be considered as a subparadigm within the more general
paradigm of terraforming. I will return to the assumptions and
theories within this subparadigm shortly.
In 1973 he published an article on the possibility of vaporising the polar caps by covering them in a dark dust layer. This would lower the caps’ albedos, thus contributing to a temperature increase. At this time there was a theory that claimed that the climate of Mars varied between a dry winter condition, and a summer condition somewhat more humid. This was supposedly due to the precession of the equinoxes of Mars.
The period was estimated to around 50 000 years. It was assumed that by heating up the polar caps artificially, it should be possible to speed up this process and thus ending the long winter within a century. Sagan proposed also that instead of dark dust, it should also be possible to use plants (!) which could grow on ice and had a low albedo.
Newer knowledge has at least shut this
last proposal out, and has also made the first suggestion less
appealing.
On an international congress on genetics
in 1963, the distinguished and highly respected geneticist
J.B.S.Haldane declared that intentional genetical modification of
humans surely had to lay millennia into the future. Today genetic
manipulation of plants and animals (in laboratories) is common.
If the church did not accept the theories, the risk was that one could end up on the bonfire, as Bruno did for his thoughts about the universe in 1600.
He claimed that the heliocentric system of Copernicus was indeed the correct one, and that the sun also moved through an infinite universe. For this the church burned him. Copernicus who invented the model in the first place was cleverer. He presented it as a pure mathematical model in order to avoid trouble with the church.
He showed that the observations also were compatible with such a model, but officially claimed that it was just a mathematical model without any relevance for the reality. However, the situation within the research of terraforming has changed during the last ten years. It has developed from being something most people considered as wild speculations which could perhaps be done in some thousands of years, into a research area that has gained legitimacy.
Many scientists also within the conservative space agency NASA have published articles on this topic. One of the most active nowadays is Dr Chris Mckay, employed at AMES Research Centre (NASA).
Actually NASA already conducted in 1976 a research survey named On the Habitability of Mars: an Approach to Planetary Ecosynthesis. The basis of this report was models similar to those proposed by Sagan, but they included research on the development of appropriate organisms that could affect the climate on Mars.
The conclusion of this report was that the terraforming would require approximately 100 000 years if all the oxygen in the atmosphere would be produced by microbiological organisms. Furthermore, the report concluded that terraforming was possible, and that the process probably could be accelerated with new technology.
Even though many of Sagan’s theories
have been left or strongly modified due to new knowledge, his models
have been stimulating on newer research. The thinking of today is
still strongly influenced by his scenarios, and we can say that the
research still remains within the paradigm established by Sagan.
The organizers found the original name of Planetary Engineering to daring. In more established scientific groups the term was still regarded as unserious and speculative. But it was no more only science fiction writers and the odd ‘eccentric’ scientist (as Sagan) that wrote about the topic. An environment had started to develop. The area attracted people, who were open to new ideas. In 1979 the conference The First Terraforming Colloquium was held. It was a true success.
The interest was big and it culminated in a book New Earths published in 1981 by James Oberg. The book presents a survey on the state of the art on that time. In addition, several articles on the topic were published. But then a quiet period arrived. Several of the participants on the early conferences had been young students or newly graduated students.
These peoples were now focused on real, and serious, research. They could not conduct unserious research, which could destroy their careers, at least not before they had gained sufficient respect within their respective research areas. Terraforming regained new momentum in the late 80’s. Fogg, Haynes and McKay were important for the reviving of the research. In 1989 the first scientific periodical that only treated terraforming was published. Furthermore, a big scientific article (Making Mars Habitable by McKay, Kasting and Toon) was published in Nature in 1991.
This publication was important since
Nature is a scientific journal of international standing.
Terraforming received therefore a stamp of seriousness. Later, film
documentaries were produced, and the first textbook has been
published. In this last period from 1987 around 40 different
scientists have published articles concerning terraforming.
The greatest expert from industry on the field is probably Dr Robert Zubrin.
The work of Zubrin – the numerous
popular science writings and his scientific articles – has
contributed greatly in gaining acceptance for the research area.
Then in 1995 the first technical textbook on terraforming, written
by Martyn Fogg, was published. Time only will show whether or
not this book will become a classic textbook in a new branch of
science.
Such a coincidence could be a meteor impact on earth with subsequent transport of organisms to Mars.
Isn’t man himself equally a cosmic coincidence?
Terraforming raises undoubtedly many interesting questions, and there will probably be many different opinions about this theme. Some maintain that the rocks and shape of the landscape itself have intrinsic value. This is an extreme point of view called cosmic preservationism. The ecocentrists are somewhat more moderate. They mean that microbiological life has a right to exist, excluding any terraforming at all if, and only if, microbiological life or higher lifeforms exist.
All this is a lot simpler for the anthropocentrists. The base for an intrinsic value is the individual’s ability for rational thinking and moral acting. Commitments towards the nature are then only indirect: everything that serves man is good. From this point of view terraforming of Mars remains acceptable as long as its serves man.
Discussion on this topic will inevitably occur.
But can dead material really have a genuine intrinsic value, unless it has been assigned by a living organism? Does the condition of Mars have any consequence for life on earth at all, and would there be any difference if Mars only existed in the mind of man?
The intrinsic value of dead material is
closely linked to the perception living creatures have of it.
This is the theory of wormholes which seems to permit travel over vast distances and perhaps through time also. Of course this theory may be falsified in the future, but it illustrates the point that a lot of the achievements of science and technology begins as imaginative thought experiments, and when they are published it is called science fiction.
The parts that have the right to exist will eventually end up as pure science. Those scientists that dare to lay hold of these new ideas in the age in which they live, and develop them further, are those scientists which may be remembered. This is the way it has been in the history of science, and this is the way it will continue to be. The condition of being a useful researcher is that one has the ability to lay hold of new ideas before others do.
If you are an established and serious researcher, you are declined to hesitate before accepting the new thoughts, and therefore it will be to late to do something revolutionary within a new research area. Those who invent and develop new paradigms are often young people, who are not established, or people that come from another field of research.
This has been typical throughout the history of science. Isaac Newton was in his early twenties when he established the basic thoughts of his paradigm in a chair in the countryside in the 1660s – and then he spent the rest of his life developing the details, as individual laws and theories, within his paradigm. Lavoisier was a lawyer who came from outside and brought clarity to the chemical nomenclature. Einstein worked as a young man alone in a patent office in Switzerland but his thoughts had far-reaching consequences.
This is also the way things have been in terraforming. Carl Sagan was in his mid twenties when he published his first article on terraforming in 1961. Those who bring forward the science of terraforming today, as McKay, Fogg and Zubrin, were all young when terraforming gained momentum in the late seventies.
It was these people as who delivered
momentum to the process a decade later.
This will probably involve some brute-force engineering. However, when this is achieved, biological microbes may be introduced. This first biological stage in terraforming, introducing microbiological life into a sterile environment and creating a sustainable ecosystem, is known as ecopoeisis.
Ecopoeisis can be the goal in itself for
the reengineering of the climatical conditions, or it may only be a
step in a longer process of a complete terraforming. If one chooses
to end the human intervention on this stage, a new sustainable
ecosystem has been given the opportunity to evolve by itself. To
continue with a complete terraforming would be a more more lengthy
task.
Given the current knowledge of the different planets and moons in the solarsystem, Mars is the only object we know once had liquid water flowing on its surface. Despite its present somewhat hostile environment today, Mars had once a big ocean on the northern hemisphere, a dense atmosphere composed mainly of carbon dioxide and significant amounts of freshwater in lakes and rivers.
These conditions are assumed to have existed in the first one billion years of the solar system. By a gradual absorption of the atmosphere into the soil and partial loss to space, the atmosphere presumably became so thin that a self-reinforcing cooling of the planet began. It is in this statement one of the most serious weak points of the terraforming of Mars lies. If too much of this early atmosphere was lost to space, a recreation of it will be a lot more difficult.
On the contrary, if most of it has been
absorbed by the regolith or frozen in the polar caps, the recreation
is far simpler. Regarding the water, we know almost certain that the
northern polar ice cap consists mainly of pure ice. The southern cap
is assumed containing a lot of carbon dioxide. In addition there are
strong indications on big amounts of water frozen in the permafrost
of the regolith. Especially in the north water may be present in the
regolith.
To achieve an ecopoeisis, we are dependent on four main issues.
By satisfying these four terms, an ecopoeisis should be achieved.
However, a certain amount of oxygen must be introduced in order for plants to survive. These four points are closely correlated. By complying with one, also the other terms will be improved.
By increasing the temperature, carbon dioxide from the regolith and the polar caps will be released, thereby contributing to additional increase in both temperature and atmospheric pressure. This will raise the temperature in some equatorial areas above the freezing point of water, thus resulting in liquid water. Increased water vapor in the atmosphere will also contribute to an increase in temperature.
Furthermore a development as such will drastically lower the dangerous radiation from space due to an increased atmospheric pressure. By introducing microbiological organisms ecopoeisis would be achieved. Due to synergies, the task is considerably reduced in complexity.
Modeling has shown that the southern polar cap is very close to evaporation, and an increase in the mean polar temperature perhaps as small as 4 K would lead to its evaporation. This would give Mars an atmosphere with a pressure between 50 and 150 millibars. There is a little uncertainty of how much carbon dioxide that is frozen into it.
Compared to the current pressure of the atmosphere on Mars on approximately 7 mbar, this increase is in any case quite dramatic.
Figure 1 Illustrated relation between the pressure of the atmosphere
and the temperature
on the southern polar cap
From figure 1 we can see that the relation between the polar temperature and the partial pressure of carbon dioxide in the atmosphere has two equilibria, one stable and one unstable.
Mars is today at the stable equilibrium marked A. A slight increase of the polar temperature will cause these equilibria to approach one another. When they meet, we will get a self-reinforcing effect as the more CO2 released from the polar cap the more the temperature is increased and the more of the polar cap evaporates.
This results in a complete evaporation of the southern polar cap, and we will end up with a pressure and a temperature a lot higher than initially. The initial heating of only 4 Kelvin of the southern polar cap could be done by solar reflectors in orbit. Additional heating will then take place due to outgasing from the regolith due to increasing temperature.
This will again be self-reinforcing. In order to establish a permanent hot condition on Mars, it is generally assumed that we must introduce supergreenhouse gases. These are gases with a greenhouse roughly 10-20 thousand times stronger than CO2. An example of such a gas is SF5CF5, which is 18 to 22 thousand times more effective than CO2 and has a lifetime of 3500 years on Earth.
By the help of such gases, we will
achieve above freezing point temperatures in an ever-increasing
equatorial belt.
Terraforming benefits from astronomy, geology, environmental science, physics and biology. This is perhaps typical for a young field of research, but also very common for this kind of applied scientific research. Anyway, such co-operative projects in new areas very often carry fruits regarding new ideas and thoughts. More basic research experiences co-operation as useful only if there is a theory present that indicates that co-operation is necessary.
This is also valid here. The whole concept of terraforming requires a wide co-operation between several disciplines. One of the most exciting things about the terraforming of Mars is perhaps that through this process we will understand the principles of climatic variation on earth, to understand the correlation between the climate and the biosphere.
Problems with co-operation are greatest
when the theories are mature, that is when the different disciplines
have grown into their own perceptions about how things are connected
or should be done.
As we can see, the paradigm of terraforming Mars is based upon a number of assumptions and theories.
Some of them are more critical when it comes to the survival of the current paradigm for terraforming of Mars, than others are. The amount of water is not very important for the method used for terraforming, but very important for the final result. The amount of carbondioxide is very important. If the amount of volatile CO2 is small, this must be obtained by other means.
Methods for this have already been proposed. For example manipulation of the orbits of some asteroids in order to get them on a colliding trajectory with Mars.
An asteroid impact would release big amounts of CO2 in the collision, because this is bounded in the rock itself. So even if the concept of terraforming is not a scientific theory in itself, which in that case should be falsifiable, the assumptions and theories are falsifiable. When new knowledge is gained we may be forced to change some of the theories and assumptions. This is the way development of research happens. New investigations give new knowledge that either supports the previous theories or render them impossible.
In the latter case, new methods to
achieve the goal must be developed. This is in compliance with
Popper’s demand of falsifiability.
One example of this is Kepler’s odyssey of the future, The Dream, where he took the reader on a journey to the moon. This was the first imaginative journey to the moon – at least that has been committed to writing, but by far the only. Numerous people have travelled on imaginative journeys to the moon after this, and then we arrived there in 1969.
The idea came when someone realised it was possible. In those times they did not have the technology or knowledge that was required, but they had ideas about how it could be done. And ideas drive the growth of knowledge ahead. But a lot of physics and mathematics had to be experienced and understood before Kepler’s dream came through.
Today we can see that a new dream is beginning to get its scientific shape. The dream about terraforming, that humanity and the entire biosphere may have several worlds on which to evolve.
The future will show just how much technology and knowledge we actually lack before we accomplish the project. Perhaps the political, ethical and economical problems will prove to be the most serious barriers to overcome.
But eventually it will probably go as
did the dream of Kepler, because the thought exists and we have
acquired a lively perception of it.
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