Terraforming Mars

What is it and how would it work? Can we do it at all?

Baseline of things

Now, assuming the marsian population didn't collapse due to an epidemic, technical difficulties, cultural clashes, war or a rogue AI taking over, we still die once we leave our housing modules, no matter how big the city. You could build domes and fill them with parks and grassy fields, but that would be a huge effort and Mars would still be a place too dangerous to live in for the general public. Let's try and solve that.

What is terraforming?

Terraforming means changing the environment of a planet or moon to make it like Earth so that humans and other Earth-based life forms can live there. This involves altering the planet's atmosphere, surface, and climate to create a habitable environment. The goal is to create a new home for humans and other living beings in space.

In the context of Mars, we would do that by introducing greenhouse gases to the marsian atmosphere to warm it up so that the poles melt and water gets re-liquefied.

What we have to do

To be able to determine the necessary outcome of our terraforming process, we'll have to assess what is currently preventing life from surviving on Mars. As of right now, the marsian atmosphere doesn't support liquid water because the atmospheric pressure is below the triple point (opens in a new tab), preventing anything from existing in a liquid state. Plants and animals also need oxygen, but micro-organisms are relatively easy to satisfy, so we might use micro-organisms to create oxygen for us. More on that later.

Technologies to use

Admittedly, finding this out has been the most time-consuming part of my research for this project. Many concepts have been presented, few have been fleshed out, and even more rarely has evidence been provided. I couldn't find a concept that actually worked efficiently enough for my taste, which is why I have prepared my own - a combination of various suggestions - for you. Much of the concept comes from James Lovelock's, who first presented his in 1984. Of course you can find more sources in the list of additional resources. Now let's jump into the details.

Super greenhouse gases, so-called perfluorocarbons (PFCs), for example tetrafluoromethane (CF₄), hexafluoroethane (C₂F₆), sulfur hexafluoride (SF₆) or octafluoropropane (C₃F₈) are to be introduced into the Martian atmosphere. This would be done with the help of hundreds of production facilities, each about the size of a car, which would be using sunlight and the Martian soil to enrich the PFCs. These super greenhouse gases absorb the energy generated by sunlight and the regolith rock.

It would be efficient to use greenhouse gases with maximum heat potential to ensure that the atmosphere produced will last for many years. Thus, we minimize the supply of these greenhouse gases, which will be needed within 1,000-10,000+ to maintain the martian atmosphere. By creating a compound of tetrafluoromethane, hexafluoroethane, and sulfur hexafluoride, one will be able to reduce the required mass of greenhouse gases from several billion tons (if CO₂ alone is used) to a few million tons. Fluorine could be released into the atmosphere and would be combined with carbon dioxide to form tetrafluoromethane. In addition to this, breathable oxygen would be produced in the reaction.

This much more efficient method would allow the realization of the project earlier than often assumed. That being said, there is a lot of debate going on around how we should terraform Mars. Kurzgesagt (opens in a new tab) for example has a great video about terraforming Mars with lasers. Feel to check it out if you think you're more of a visual learner!

Duration

After about 100 years, temperatures on the surface of Mars would average about -40 °C - instead of the previous -60 °C. The air pressure would rise from 0.3 to 2 bar. However, it would take another 500 years until the water in Mars would liquefy and reach the surface. The increased atmospheric pressure would prevent the evaporation of water we previously explained through the triple point. After time, lakes and seas would form again.

After a total of 600 years, Mars would be restored back to its former state, because the living conditions on the red planet were not always as threatening as they are today. Investigations of NASA prove that Mars fulfilled all conditions for life 3.8 to 3.1 billion years ago.

Additional Resources

1.
You can get more detailed information on SpaceX plans to terraform mars on SpaceX dedicated Mars page.
2.
Kurzgesagt has a truly great and beautifully animated video about the process of terraforming Mars which might make it easier to understand.