Venus Cloud Cities

As we found out earlier, Venus is not too good of a first multi-planetary colonization target. However, we could come back to Venus and build efficient yet simple structures that could harbor life in the upper atmosphere of the planet. How?

Floating Cities

No matter how far we progress technologically, setting up a city on a 50 kilometer high pole made out of whateverite exposes us to a huge risk with every major weather condition it has to withstand. So, let's just not do it. Similarly to a weather balloon that naturally rises to their operating level high up in the atmosphere, we could make our Cloud Cities float in the venusian atmosphere. They would float at a level where pressure is equal inside and outside of the habitat and could be constructed out of light material, as long as they are resistant to the sulfuric acid raining down on Venus.

Tensegrity structures

Tensegrity is a term invented by Buckminster Fuller, especially known for popularizing geodesic domes similarly to the one we would want to use on Venus. It's a blend word for "tensional integrity" and refers to an architectural and engineering system that consist of a combination of tension and compression elements.

These structures are composed of a network of rigid bars or struts, which are connected by a series of continuous tensioned cables or wires. The unique characteristic of tensegrity structures is that the struts do not touch or directly support each other, but are instead suspended and stabilized by the tensioned cables.

Utilizing tensegrity or, for example, a Buckminster Fuller dome, we could achieve lightweight but strong construction of our Cloud City. Earthlike air inside of it would not only support earth life inside but also act as a lifting gas to let our colony float in the habitable region of the atmosphere.

Since pressure levels outside of the habitat are similar to Earth, we also have no need for clumsy spacesuits that not only take literal hours to a full day to take on but also make it hard to do any physical work in. The lower pressure also enables us to build more lightweight structures and save significant amounts of materials because we don't have to build to withstand 10 tonnes per square meter of outwards pressure, like for example on the ISS.

Ingredients for life

One of the biggest players when it comes to the ingredients for life surely is Nitrogen. Muscles, blood, skin, hair and nails all need nitrogen when growing or replacing their cells. All kinds of tissue repairs require nitrogen and catabolic processes require proteines in the form of nitrogen to break it down into amino acids that are necessary for providing cells with their necessary energy. Nitrogen is pretty rare usually, but the atmosphere on venus consists of about 5 times the amount of Nitrogen in Earth's atmosphere, so we probably won't fall short on that. We would effectively never run out of nitrogen for plants and could potentially even supply surrounding Space Habitats with it.

As we already sorted out earlier, there is arguably hardly accessible water vapour in the atmosphere of Venus, but we could extract it via chemical methods or through the use of Solar Furnaces that heat the sulfuric acid.

Last but not least, for CO₂, there is no need to put in all the effort it would take us to extract it from a near vacuum on Mars since it is readily accessible in the atmosphere.

Construction

"Creating" the necessary construction materials to expand and build new Cloud Cities in the atmosphere of Venus is quite literally the same as in Minecraft Skyblock. Now, this might sound like the dumbest shit on this website, but please, hear me out:

Once you have water and CO₂, which we just realized we do have, you're only missing some trace elements and soil to grow trees in our habitats. These could come from Earth in the early days of our colonies of Venus but could later be extracted by asteroid mining. Once you have all four of those, you can basically grow trees directly from the atmosphere.

There is a great explanation by Richard Feynman about how carbon dioxide and water react with a plant to supply it with it's necessary ingredients for growth.

Since trees are 90% either just water or CO₂, most of the mass of our trees is extracted directly from the atmosphere, enabling us to literally "spawn" construction material - wood - out of "thin" air. You might get why I made a Skyblock reference now, although it's much easier to execute this in Skyblock, gotta give you that. Anyway, wood isn't resistant to sulfuric acid, so we yet have to figure out how to build resistant glass to cover our habitat in and could use the wood for construction within our habitats. This should not be an impossible task in the long term since the surface of Venus is partly covered in sand that could be extracted and heated to form glass tiles.

Man, this section is filled with Minecraft references, although the latter one wasn't even intended.

Conclusion

What's the learning of this chapter? Easy. Venus atmosphere is a great colonization target for once we learned how to elegantly navigate planets by rockets and whatever other method of interplanetary transportations might await us in the near future. However, it would be a much less fancy and more minimalistic existence than living on a terraformed Mars that's basically mimicing the conditions on Earth.

It is yet to be determined if humans will ever find the hardships of colonizing Venus bearable for the lifes humans could live on it. All I tried to explain here is if it was possible and the answer is "yes!". It certainly could. Time will tell if it's going to.

Additional Resources

1.
Robert Walker created a very thorough article about Venus and potential issues on it on Science2.0. Feel free to check it out if you want to go into greater detail on this.
2.
If you find Tensional Integrity equally as interesting as I do, check out the Tensegrity Wikipedia Page, it's surprisingly good at explaining them.