Cost-Benefit of Terraforming

JoshNH4H · 2011-11-23 14:13:11

Terraforming a planet is one of the largest projects that we as a species could undertake. It is a massive undertaking that would cost hundreds of billion of dollars at a minimum, with a more reasonable estimate being somewhere in the trillions. It would likely take a long time, and there would of course be a cost in human lives, though it would not be inherent to the process and could be minimized if care was taken. Current research, however, does seem to show that the terraforming of Mars (Let's focus on Mars for the moment, if only because it has received the most attention and is thus a relatively smaller unknown) is very possible; good engineering will lead to a leveraging of resource input to levels that are comparatively similar to some of the largest megaprojects done on Earth today (maybe?-even with all of the qualifiers ).

My question is: Is it worth it? It gets difficult to project the future this far in advance, given that just about everything is on the table (after all, if you take things off the table for models' sake that are physically possible, your model loses that much in credibility).

The first question is economic return on investment. Terraforming Mars is going to cost a lot of money. What money will it return? It will make it cheaper to live on Mars and make it easier to exploit the local resources, thus making the economy more productive and therefore generating value for the economy. It will also make it more attractive to colonists and thus increase the population, which will increase the size of the Martian economy and result in a net gain for its society. Further, it may make people on Mars happier, which is something that is difficult to put a price on but has a significant value, especially when considered over large timescales.

On the other hand, there are certainly costs associated with the Terraforming of a planet. In addition to the massive initial cost of creating a biosphere on the planet, there will probably be some costs associated with maintaining it, or fixing it when it goes wrong; though biological systems inherently tend towards chaotic equilibrium, there is no reason why that equilibrium will necessarily lie in a range that is comfortable for humans. I know KSR talks about continuously releasing CFCs, HFCs, and CHCs to keep the temperature at acceptable levels; Midoshi has said that it may be difficult to create living organisms that are capable of doing this on their own, though it will be by no means impossible especially given advances in computational biology which will eventually lead to the synthesis of gene sequences that lead to the production of "made to order" enzymes that will make it possible for organisms to make these compounds, when implanted.

There may be more costs than that, however. Weather on Earth is very corrosive. I know people from LA who say that cars last nearly forever there. Meanwhile cars where I live in the northeast do not last nearly as long because of the temperature swings and the salting of the roads that is done during the winter. This will detract somewhat from the economic gains made possible by terraforming.

Further, it seems possible that terraforming may actually decrease the ultimate carrying capacity of the planet Mars. Biospheres are amazing in their ability to self-balance, but are not very efficient when it comes to turning raw solar energy into energy that ultimately makes it to humans. Terraformer has often pointed out that it should be possible to boost the efficiency of photosynthesis with time, and that is a very valid point, but even so it will probably remain less efficient than power generation. Likewise, a smaller environment contained within a hab is likely to be rather simpler than an entire biosphere and since there will be few extraneous cycles (the relatively minor cycles, after all, can be handled and much simplified with machines), will be able to support more people per square and cubic meter than a biosphere. Given the tendency of population to grow in a malthusian manner, this may become an issue eventually.

Now, the magnitude of these numbers is more or less irrelevant if you have forever to work with; even if terraformation yields a net gain of one penny for year, over enough years this will lead to it being worth it. However, one really does have to ask how many years there are. Approximately 5 billion years from now, the sun is going to explode, and it will be easier to find another planet in another system than to drag this one, which we've already terraformed, elsewhere. But there are other limits. Technology is progressing at a fantastic rate. How long will we need planets for? (Do we even really need them now?) For how long will we have physical bodies? In my opinion it will not be for that much longer. I think 300 years or less. It is very possible that terraformation will not be done in 300 years.

Also, there is always the need to consider other solutions. For example, instead of terraforming Mars, why now aeroform humanity? Wouldn't it be cheaper (and potentially have a lot more rewards) to throw money into biomedical research until people can walk on the surface of Mars, or walk on a martian surface that has been only slightly modified?

I am not well versed enough in the topic to feel confident in assigning numerical values to these; I'm not sure anyone is. But before Terraformation commences, I think that these are questions that need to be answered.

SpaceNut · 2011-11-23 16:04:19

The question of is it worth it to teraform Mars at any time in the future is a yes as just one large sized rock striking the moon or the earth would be devistrating to the only craddle of life we have known.
How we go about it depends on biological experiments as what we have found from the ISS is that evolution leaps and bounds once in earth orbit...

Terraformer · 2011-11-24 10:37:30

One should not abandon terraforming on the assumption of a technological singularity making it irrelevant. Prediction is hard, especially about the future, and the singularity is already on shaky grounds.

Primarily, the unknown in the cost-benefit analysis is the first part - we can get quite a good idea of the benefits under different schemes. Would a cold, 100mb, Arctic Mars be better than the current state? Sure, you have to insulate your habitats more, but the pressure difference is lower. The winds are going to be stronger, but if you can get a hydrological cycle going, you won't get sandblasted each time there's a storm. Though that brings it's own problem, namely risking glaciation... what we need to do really is to find conditions that would trade off the pro's and con's of a scenario to find if there'd be a net benefit. For example, a cold, 300mb Mars with just enough free water to find the soil tight but not much else would allow the building of very large domes colonies, very cheaply, and homesteading would become viable. A warm, 50mb Mars with an active hydrological cycle would allow modified crops to be grown on the surface, freeing up pressurised space for humans and animals. How much would it cost to get Mars to this stage? Depending on how much CO2 is available, we may be able to use bacteria to cheaply get it to such a state. This could possibly be one that would allow it to reach the 300mb pressure state without any more human input. 300mb of atmosphere on Mars would be ample radiation shielding, so houses wouldn't have to have rock piled on them, and people wouldn't be limited in the time they could spend on the surface by the risk of radiation sickness.

I don't understand why you think terraforming would lower to ultimate carrying capacity of Mars. If it's anywhere near that point, most of the planet will be intensively farmed anyway, and if they need to they will greenhouse the farms, for a much lower cost that it would be on a non-terraformed planet. I seem to recall that plants can't handle intensities of more than 100W/sq.m anyway - clear skies could perhaps make up for the greater distance? As for your point about power generation being more efficient than plants... yes, humans can't (yet) eat electricity, so it's got to be used to make food anyway, which results in significant inefficiencies.

Glandu · 2011-11-25 03:22:48

This book I am currently reading points out how environments can collapse, and take with them the society living off them. Collapse can come from climate change, man-made environment destruction, or both. Most climate changes he states come directly from solar activity(especially destructive for the first scandinavian settlement in Groenland) - something that we don't control - even on a terraformed planet.

My understanding of Josh's message is that controlled biospheres are less vulnerable to natural or man-made environmental destructions. I'm not sure of it, but it is definitively a point to take in account. Biomes we make a living from are definitively not forever, and the fate of medieval Groenland or Easter Island are a definite warning. The slower the environment is to rebuild itself is, the easier it is for us to destroy it forever - and to die.

Grypd · 2011-11-25 05:07:01

There are three stages in the terraforming process these are Initial, Partial and of course full.

Mars at the present does not have a carrying capacity the missions sent there will have to be housed in specific habitats with the same tolerances as if they where in deep space and if it comes to leaving Mars at this state then the new home of Humanity will be O'Neill type colonies in space. These will be safer and have access to much more wealth in the form of asteroidal material than any Mars colony.

Certainly I dont want Mars to be the equivalent of an Antartic research base. This is a deliberate statement as Mars does have water and volatiles locked into its surface and if we stick a building on top and add heat we have building damage.

So we want to Terraform Mars well the first step is to add light and heat. Soletta arrays increasing the suns luminosity on Mars will be the cheapest option. Soletta arrays are large mirrors of thin reflective material and we have been testing the development of these as sails. This will have two effects the first is of course Mars gets brighter and Warmer and we begin to notice an increase in Air pressure. But the effect is also to improve our ability to grow crops and of course to create Farms.

Bioengineered crops designed for the low light enviroment of Mars grown in CO2 pumped in from the Martian atmosphere filled Farms could produce our first product available to the rest of the solar system. It will be cheaper to grow a lot of food on Mars and to deliver it across the solar system than to send it up from Earth. We have to assume and rightly that Mars will not be our only point of interest and that we will be resource hunting in the asteroids and of course developing the Moon and further out. Mars has less gravity and we could build larger farms without the need to provide artificial lights if we go this way. This means in any economy that using NIMF rockets or mass driver technology Mars could provide food across the solar system to our other outposts where the further they go out the less sunlight they have and of course space used up for plants is less space used up for something else. Of course extra light and heat also allows solar power to really begin to function and as air pressure increases so can we use windmills this provides us with more electrical power on the surface but that is just a bonus.

This is initial terraforming and cost/benefit analysis is reasonably cheap cost to build and maintain with a very large benefit.

Partial terrforming where we get to the point air pressure is such that we have plants growing outside will depend on how we get about it. We need to increase the atmosphere and to provide more heat be it large heat producing reactors on the surface or to start a super greenhouse effect by use of chemical plants etc. Do we send kuipler belt snowballs to Mars to impact on the surface, possible? We may not need to do that depending on just how much volatiles are locked up in the surface and poles of Mars. The cost is unknown but large but the benefits is to safety and that carrying capacity of the planet. If we only need a face mask and warm clothes to walk around the planet that is much better than full spacesuits.

Full terraforming now that is hard to speculate. Just how do we give Mars a magnetic field?

Last edited by Grypd (2011-11-25 05:10:20)

Terraformer · 2011-11-25 10:00:29

Well, I don't think we're ever going to really "fully" terraform anywhere, in terms of having a breathable atmosphere that is stable over billlions of years, but partial terraforming (Proteroforming) is feasible most places, even if it just means a 50mb CO2 atmosphere. The benefits of radiation protection and less stress of habitats, meaning vast inflatable domes can be built, are significant. Depending on how much it costs to get to this state... certainly, if food can be grown on the surface for relatively minor alterations costing in the low dozens of billions, someone would do it.

SpaceNut · 2011-11-25 10:01:23

Steps all in the process based on cost to garner progress and efforts by the masses to establish beyond the elite few.
Mars does have remant magnetic fields maybe there will be a way to link them to start the process.
From exploring or own field we have learned that a thick atmoshphere and planets body mass are part of the overall equation also proximity to the sun, rotational speed ect....

Midoshi · 2011-11-25 13:03:28

Terraformer wrote:

Well, I don't think we're ever going to really "fully" terraform anywhere, in terms of having a breathable atmosphere that is stable over billlions of years...

I don't think that's a very fair criteria. Earth itself has only been well oxygenated (i.e. able to support aerobic megafauna) for about half a billion years. And even over that time the O2 pressure has undergone fluctuations of over 100%.

I completely agree with you that "full" terraformation is much more difficult (and not necessarily as desirable) as simply making a planet moderately clement to life. I just want to disabuse you of the notion that a highly Earth-like terraformed planet would have as much long term stability as you seem to think. Not that it wouldn't be possible to construct such a system artificially, but it would be a level of geoengineering even beyond terraforming.

JoshNH4H · 2011-11-25 15:17:22

I'm glad to see that this topic has incited so much discussion! I find that terraforming is a very interesting branch of engineering, but I have been less than fully interested in it in the past for the reasons I detailed in the above post.

With regards to specific people's points:

Spacenut- Just because we are not terraforming Mars does not mean that we will not have self-sustaining colonies there. It is very possible to have self-sustaining colonies without terraformation, though day-to-day operating costs will be higher. That is where the cost-benefit comes into play.

Terraformer- I don't doubt that just about anything along the steps of terraforming would be an improvement over the state of Mars as it currently exists. My question is rather if it is worth the cost of getting it to that state. Given that earlier steps along the terraforming process will probably be easier than the later ones, they may indeed be shown to be worth it. With regards to why terraforming may actually reduce the ultimate carrying capacity, Glandu was exactly right; using electricity to, for example, complete the water cycle is a hell of a lot less land and resource intensive than using nature.

Further, with regards to uploading/otherwise having little use for planets, it might be very hard to predict but it is nevertheless worth thinking of, given that it is a very legitimate possibility. The future is always weirder than we imagine it to be. After all, how could the imagination of any one person or any group of people be greater than the combined efforts of humanity to make their world better?

Terraformer · 2011-11-25 17:17:52

Well, I consider it unlikely that I would upload, were the option available. It's a very big stretch to imagine everyone doing so, even if most have the implants that would lead to it (it would also be quite a shame, as well - an advanced society that could have had the stars, turning in on itself...). If we reach that point, then all bets are off, and we'll probably terraform simply for it's own sake, because if you have the resources to throw at the project, why not?

My point about the theoretical Martian carrying capacity still stands, because if we're hitting the maximum, the planet will be absolutely covered with domes and polytunnels by that point, with the internal environment being perfectly regulated anyway - while still taking advantage of the radiation protection and pressure provided by the atmosphere. Nevertheless, such a project would only be required if Mars was to be a Hive world, supporting a population in the 100s of billions. I don't think carrying capacity will be an issue for some time...

Ultimately, a cost-benefit analysis comes down to cost. If a warm wet Mars can be (re?)created cheaply enough, I think it offers too many benefits to not do. After that comes the long drawn out task of generating Oxygen (Birch-esque thermal reduction of the regolith using highly focused sunlight notwithstanding). This may turn out to be supportable for a comparatively low cost per year, and involve nothing more than managing the peat bogs and forests to ensure Carbon is locked up (in the process giving Mars it's own fossil fuels...).

JoshNH4H · 2011-11-25 18:03:49

It is and always has been my contention that uploading will not be a choice made at some point but rather a slow process which happens largely without anyone else noticing. It's already begun; how much of your interaction with people occurs over the Internet (This includes people whom you do not meet in person, such as myself)? What proportion of the information that you have access to at any given time is not located within your brain (Yes, this includes paper. In a sense, civilization is the story of humankind slowly spreading their consciousness off of carbon/water based computers and outside the boundaries of their skull)? How many people do you know who are inseparable from their smartphone?

It will at some point be the natural extension of this to have direct mental interaction with machines without the intermediary of slow appendages and inaccurate and limited sensory organs. From that point, it is likely that more and more of people's consciousness will be held on these machines. At some point, the biological components will inevitably die. But the portions of the person on the computer can live on. Further, if the biological component was but a small piece of the total consciousness, it can continue unhindered. In the alternate situation where we can prevent biological death, we are presumably not far down the line from engineering biological superbeings. In either case, terraforming becomes extraneous. Further, without bodies, travel to the stars becomes all the easier. We, after all, don't need to go to Mars because the Earth has run out of room (Whether we have or not is up for debate; going to Mars won't solve the problem).

In this case, all bets are not off. The facts of resource acquisition and usage remain the same, but merely differ in detail. Just because we have uploaded to computers does not mean that we will have trillions of dollars (equivalent) just lying around to terraform a planet for no reason.

In the alternate situation: Yes, I am talking about a hive world, or something close to it. Essentially, slow paraterraforming. It seems much less resource intensive than building a whole atmosphere and complex biosphere from scratch, as well as the fact that it will be able to sustain more people.

Midoshi · 2011-11-25 20:52:59

One thing everyone seems to agree on is that "proteroforming" Mars to a marginally habitable state is (relatively) easy and high payoff. Going further becomes increasingly expensive for a decreasing short-term benefit.

In my view, paraterraforming is not a replacement for most of the benefits of engineering Mars' climate, especially with regard to thickening the atmosphere. One major benefit is the reduction of atmospheric variability, which stabilizes not only diurnal temperature swings but also makes aerobraking and aerocapture in the upper atmosphere more predictable and therefore safer and easier. It would also allow for aerodynamic spacecraft landing, doing away with expensive, less scalable, and less reliable landing techniques like lithobraking and the sky-crane in favor of the simpler and better tested/understood capsule+parachute or lifting body configurations used for Earth. If the atmosphere was thick enough, designs originally intended for Earth reentry could even be reused with little or no modification, which would have huge R&D savings. Thickening the atmosphere would lessen the flux of small meteorite impactors and greatly reduce the impact velocity of larger objects. None of these things can be accomplished by paraterraforming. There are also a slew of scientific questions about Mars' past and planetary science in general that could be addressed by using the planet as a sort of massive climate experiment.

Now don't get me wrong, I think paraterraforming will begin first and be synergetic with climate engineering later. But I do not think it qualifies as an easier alternative to terraforming, and therefore cannot be used as an argument against it.

JoshNH4H · 2011-11-25 21:16:03

I'm not necessarily arguing against the idea that terraforming is "worth it." Rather, I would just like to point out that (Given that this debate was popularized IMO by KSR in his Mars Trilogy), the question of whether or not to terraform is viewed more in ethical terms rather than economic ones (with the relatively obvious answer to the ethical question being that there is no ethical problem with terraforming); I think that the economics of terraforming does need to be looked at because if it's not worth it then terraforming simply as a matter of course is a tremendous waste.

Nevertheless, spreading black dust on the polar caps is certainly simple enough to be worth it the cost. If at that point methane and ammonia releasing microbes could survive on the surface (IE to warm the planet using methane and ammonia as greenhouse gases, keeping in mind that they will survive longer in the Martian atmosphere due to a combination of lower UV (farther from the Sun), lower exobase temperature (according to Midoshi, an atmosphere with less CO2 has a lower exobase temperature), and having less oxygen in the atmosphere.

Beyond that, though, things get more expensive; and when we're talking engineering on a planetary scale, more expensive is quite a proposition.

As a simple terraforming method, though, what does everyone thinking about grinding up Carbon real fine, and letting it go in the midst of a dust storm?

SpaceNut · 2011-11-25 22:22:38

I was looking at this in the near term as far as my last post JoshNH4H and not to a long term sustainable settlement but what is the size population that marks a permanent colony rather than a transitory state of a site having a population that changes every 5 years. How far off is the permanant status declared (a decade or hundreds of years) to once the flag and foot prints are done. Were does the cost line up with a mass transit system to get its quantity to mars for this settlement.

As Midoshi pointed out a thicking of the atmosphere even if not breathable sure makes the EDL a less costly event as a simular earth entry shielding would be useable but where is the threshold of this level or altitude...

It appears that there is a chance that underground biology may be producting methane but to what level can we ramp up its out gassing to satify the thickening quantity and for how long would this process need to go on to get results.

Midoshi · 2011-11-25 22:42:17

Hm, I always figured the economic issues were more obvious and important than the ethical issues. If it's not practical to do it, then any ethical debate is academic and ultimately pointless. I suppose it does make for a more engaging novel though.

I have always been of the opinion that focusing the first stage of climate engineering on the polar caps would be the most efficient approach. They only comprise ~1% of the planet's surface but contain the vast majority of the volatiles which are readily releasable. Whether by lowering albedo, using impactors, increasing insolation with orbiting mirrors, releasing greenhouse gases (which will concentrate near whichever pole is experiencing seasonal CO2 condensation), or (more likely) a combination of the above tactics, I think this will be the starting point for any practical terraforming program.

JoshNH4H · 2011-11-25 22:58:10

Spacenut, fair enough. I think that we can at least agree that enough work to vaporize the polar caps and perhaps a little beyond that will be worth the cost; beyond that is of course up for debate.

SpaceNut · 2011-11-25 23:45:01

Melting Mars To Create A New Earth

They found that a compound known as octafluoropropane, whose chemical formula is C3F8, produced the greatest warming, while its combination with several similar gases enhanced the warming even further.
The researchers anticipate that adding approximately 300 parts per million of the gas mixture in the current Martian atmosphere, which is the equivalent of nearly two parts per million in an Earth- like atmosphere, would spark a runaway greenhouse effect, creating an instability in the polar ice sheets that would slowly evaporate the frozen carbon dioxide on the planet's surface.

The polar ice cap is boiling off into the atmosphere! But don't worry - these 'melting' icebergs are on Mars

Mars has dramatic carbon dioxide atmospheric shifts
Great image showing concentration to 30% higher than other areas. This melted would get the atmosphere to twice what it currently is.

Terraformer · 2011-11-26 08:19:10

But the question is, how many gigatonnes is that?

Terraforming Mars might turn out to be the only way we'll find out if there's life... hmmm, terraform initially without using biology, check for any life coming out of it's dormant state, and then proceed with biological terraforming?

We need a damp Mars before we can get the microbes going. That might only be a mere doubling or tripling of the current atmosphere.

Whatever we do, though, Mars will take centuries of climatic shift once we've got it initially Proteroformed, as the ice sheets will take quite some time to melt.

JoshNH4H · 2011-11-26 09:30:02

Life is pretty versatile; the more we adapt Martian conditions the easier it will be for them, but we could conceivably get them going quite soon.

You'll have to jog my memory as to what proteroforming vs. whatever other stages we set semi-arbitrarily are. I do believe that thread was some time after 2008. Keep in mind, however, that a warmer Mars does not mean a Mars where ice caps are unstable- Earth's average temperature is much higher than Mars', yet we still have ice caps.

Terraformer · 2011-11-26 09:52:05

Proteroforming, as I use it, means a habitable (for a given definition of "habitable", which may extend down to 200K and 50-60mb) atmosphere which isn't breathable - basically, one where humans don't need a pressure suit to survive. Crops may or may not be grown on the surface. For example, a warmer Titan with a few modifications (to remove the more toxic constituents of the atmosphere) would be proteroformed.

Midoshi · 2011-11-26 10:10:47

As I recall, we chose the name in reference to Earth's Proterozoic Eon. The name means "early life", so "proteroforming" would suggest "early forming" or the first stages of making a planet habitable. The idea is that a stable biosphere of primitive microfauna (and even mesofauna like nematodes and tartigrades) could be possible with some low level aerobic activity, but megafauna (like humans) are not yet supportable. In other words, a climate analogous to Earth's Proterozoic. I think that is also fairly consistent with Terraformer's description.

JoshNH4H · 2011-11-26 19:08:59

Midoshi and Terraformer, thanks for jogging my memory. I was pretty sure that that was what you were talking about but I didn't want to take the risk that I was mis-remembering.

In any case, I do agree that that degree of terraforming would be relatively easy, and would almost definitely pay off in the not-very-long-run though following stages would likely be rather difficult.

Terraformer · 2011-11-27 08:39:24

Hmmm. Perhaps we will end up following a mixed approach, involving liberating as much CO2, N2, and O2 as is feasible to do so before it becomes uneconomical, perhaps resulting in a Mars that is ~-20 deg. c. with a ~200mb atmosphere, and then Paraterraforming beneath this. The pressure difference will be significantly lessened for a start, and construction would be an easier matter due to being able to use Airships (giant Hydrogen filled Hexagons?). Pressurise it to say 300mb, and you have 10kPa/m^2 trying to lift the sky off. Leaks will be less of a problem than with a low grade vacuum on the outside as per standard paraterraforming scenarios, and we won't have to worry about impactors destroying the world sky. If we can make it biologically self repairing, such a worldhouse could last for millenia without human intervention, so even if the society on Mars regresses to primitivism, they'll be safe. Oxygen levels could be maintained at the desired level by slowly mixing the atmosphere with that outside, eventually leading to full terraformation, though the worldhouse might have to be maintained to keep the temperature above freezing (I trust a giant greenhouse which can be repaired by a planet bound society more than I do a set of giant space based mirrors). Overall, I think this is a scenario which offers the best outcome for Mars within a reasonable time scale. Depending on oxygenation rates, we may be able to leave gaps in the worldhouse roof?

I'm rereading my terraforming book in case they ask me about it at my interview at Cambridge...

JoshNH4H · 2011-11-27 14:34:02

Well, paraterraforming can proceed as necessary. There's no need to go building a worldhouse right away, given that quite simply there is no need for it. Dome what needs to be domed, and perhaps eventually Mars will be paraterraformed, if necessary. If we don't upload or otherwise shuck our physical bodies in the meantime, or invent drexlerian nanotech, or become godlike superbeings.

SpaceNut · 2011-11-27 19:22:27

Did a little search on the Nasa web site to be surprised at the results as well as the respective age...

http://nai.nasa.gov/news_stories/news_detail.cfm?id=212
http://quest.nasa.gov/mars/ask/colony/E … orming.txt

First, greenhouse gases, like chlorofluorocarbons that contribute to the growing ozone layer on Earth, will be released into the atmosphere. This traps the heat from the Sun and raises the surface temperature by an average of 4 degrees Celsius. In order to achieve this, factories would manufacture chlorofluorocarbons derived from the air and soil. A single factory would require the power equivalent of a large nuclear power plant.
The increasing temperature would vaporize some of the carbon dioxide in the south polar cap. Introducing carbon dioxide into the atmosphere would produce additional warming, melting more of the polar cap until it has been vaporized completely. This would produce an average temperature rise of 70 degrees Celsius.

Even schools get into wanting to be a colony of the future...
http://quest.nasa.gov/qna/research/marscolony.html

Of course an atmosphere protects us when we go
http://quest.arc.nasa.gov/mars/ask/huma … ilding.txt

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Cost-Benefit of Terraforming

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