I had mentioned in the
Semi-Official 6.x Suggestion Thread that we could use more options for terraforming (at higher tech levels). But I just came across some real-world proposals for terraforming Venus and I wanted to discuss the potential for some of this as game suggestions.
Granted, while the gravity is about right, Venus is otherwise incredibly inhospitable. The temperature is insane and so is the atmospheric pressure. Even considering that... According to the AuroraWiki article on
Terraforming, it would take a single terraformer about 96,000 years to reduce the pressure to a tolerable 4 atm!
That just sounds
insane to me.
I would point out this Wikipedia article on
Terraforming of Venus. And I want to emphasize that these are
serious proposals published by scientists and other professionals. (See the
References.) And they would require much,
much less than tens of thousands of years to implement.
I want to discuss a few of them:
- Floating Cities - At a certain high altitude the temperature and atmospheric pressure is actually habitable to humans. The only problem is the atmosphere is caustic and unbreathable. But you could have enclosed dome cities that float by the simple virtue of having a nitrogen/oxygen atmosphere, which is lighter than CO2.
It was estimated that, eventually, Venusian floating cities may become economically viable. They can also remove and process the CO2 in the atmosphere, converting it into needed oxygen, carbon, and - with an import of hydrogen - water.
CO2 removal could be accomplished by various methods. Here are some relevant articles:
Aside from algae or bacteria specifically bred or engineered for CO2 removal or H2 gas generation (such methods exist), let's not forget the simple virtue of being large greenhouses, naturally converting CO2 to oxygen and plant matter/soil.
The carbon that is removed could also be made into carbon nanotubes or graphene sheets, very suitable for construction. Thus, such cities could use the CO2 as raw material to expand.
With huge numbers of such cities, they would reflect/absorb a significant part of the sun's rays while removing a lot of CO2.
- Introduction of hydrogen - This involves bombarding Venus with hydrogen. It can react with the CO2 to produce carbon and water by the Bosch reaction. Venus is so hot that the reaction can work, with the catch that it needs an aerosol of iron as a catalyst to speed it up. The hydrogen can be mined from one of the gas giants or, as ice, from their moons. It also requires large volumes of iron (and/or nickel). But many asteroids are mostly iron and nickel, anyway.
Estimates predict this could reduce it to 3 bars of atmosphere and produce so much water that it would cover about 80% of the surface!
- Capture in carbonates - The idea is to use magnesium and/or calcium to serve as a sink for both carbon dioxide and sulfur dioxide. A lot of this could come from mineral deposits on the surface. (By one estimate that alone could reduce Venus to 43 bar.) But more could be imported.
While not related to Venus, I also want to mention
methane. This gas is not uncommon on planets with an atmosphere. Most significantly, methane has 25 times the global warming effect as an equivalent amount of carbon dioxide! So the presence of methane can have a
huge impact on temperature.
With growing concerns over global warming, there has been interest in
Sequestering Methane (article).
There are several methods possible. In nature, atmospheric methane reacts with the hydroxyl radical (OH) in the troposphere or stratosphere, which gradually breaks it down. There's also a "methanotrophic bacteria" in the soil that oxidizes methane into CO2 and water, using it for energy. Some of it can get stored as methane hydrate, such as in ice, too.
So... What's my point?Why couldn't there be more methods to terraforming beyond just building planetary Terraformers or Terraforming ships with Terraforming modules? That is, how about some new approaches that, with enough research and enough of the right resources, could speed up the process for certain planets with certain types of atmosphere?
The only minerals we mine are Trans-Newtonian. (The rest are considered "trivial"...?) But among
Trade Goods we have Chemicals, Precious Metals, and Plastics.
Suggestion 1: If we could mine
Hydrogen (and/or
Iron), perhaps we could use it in a new terraforming option to
convert an excess of oxygen pressure (atm) or carbon dioxide pressure (atm) into water (as a liquid, solid, or vapor, depending on temp)?
And aside
from using
Hydrogen, there are many easier ways to reduce an excess of
Oxygen as it readily oxidizes many materials (including iron, magnesium and calcium). Such a job should
not require huge and expensive terraforming facilities to do this over a period of centuries.
Similarly, for planets with too much
Methane, one could mine
Oxygen and introduce that. A reaction with oxygen would produce carbon dioxide and water. Assuming that oxygen can be readily mined and imported, this should be much easier and faster than a "scrubber" or filtration.
Suggestion 2: Or maybe we could mine
Magnesium or
Calcium and use it to
Sequester Carbon Dioxide or a few other gases, such as
Sulpher Dioxide.
Suggestion 3: Instead of the above, maybe we could have a new terraforming option to do similar without the hassle of mining/buying and transporting new materials? Currently, we must
remove a certain gas for the purpose of reducing atmospheric pressure. Likewise, currently, we can add a generic "greenhouse gas" to warm up a cold planet or add an "anti-greenhouse" gas to cool a hot planet.
With high enough research, how about new choices like "CO2 Sink", "Methane Sink", or "Nitrogen Sink" to represent newly researched methods to sequester certain gasses? (That is, methods that are faster that direct removal, such as filtering it out of the air and compressing it.)
Suggestion 4: For certain planets where the atmospheric pressure is too high and the colonization cost is astronomical (like Venus), perhaps we could have an option to build an equivalent to a
Sky City? In game terms it might cost less than building on the surface, but perhaps it would not allow building certain types of facilities on the surface? Or, perhaps it would have a specific population limit and require a certain amount of Trans-Newtonian elements to build?