Terraforming is a process, in which a planet or other object, such as moon, is transformed to resemble the Earth. Terraforming requires often changes to planets atmosphere, temperature and other factors. Often these changes require importing of additional resources, which are not found on the planet we are planning to terraform. With terraforming, humans, plants and animals could live on a foreign object just like on Earth.
Requirements and methods
To be able to support life, planet has to have certain features, which could be created by terraforming. None of the planets we know have all the required properties for lifeforms we are aware of, but many objects have qualities that are quite near optimal.
Water is an essential element to life. Water is an abundant on Earth, but unfortunately the closest objects to us, such as Venus and Mars, are lacking great amounts of water. Water consists of hydrogen and oxygen, so it can be also used to produce oxygen. If water isn’t readily available, we could import hydrogen to create water, if oxygen is already available.
Breathable atmosphere is also an very important element with water. Without these two, people are unable to live on the planet. Ideally, the atmosphere would consist of nitrogen, oxygen and other elements, such as carbon dioxide. The atmosphere should be thick enough to allow breathing, and it also creates a greenhouse effects, which helps to keep the temperatures stable.
Temperature should be quite optimal for humans to thrive. The planet we’re trying to terraform should have areas, in which the temperature is above the freezing point of water. Temperature can be controlled with greenhouse effect. If this is not enough to raise the temperatures, the temperature can also be increased with mirrors pointing solar light to the planet. Alternatively, if the temperatures are too high, solar shades can be used to decrease the temperature.
The soil should allow plants to grow, which requires vast amount of different minerals. Its probably, that we need great amount of soil transformation, with help of fertilisers, to be able to grow plants. Its also possible, that we could genetically engineer plants to be able to survive in the harsher conditions. The soil should be also safe for life, as, for example, the soil of the Moon may be harmful to humans.
One of the important features of magnetic field is its ability to protect inhabitants from space radiation. Space radiation is very harmful for humans and other life. Without a magnetic field, humans wouldn’t be able to roam freely on the terraformed planet. Only a couple of the possible objects for terraforming are protected from space radiation. An artificial magnetic field could be created with a network of strong orbiting magnets, or we could try to restart the internal process on the planets that create a magnetic field.
For comfortable life on a planet, the rotational speed should allow day-night cycle that resembles the one on Earth. Even though most animals and plants would probably be able to withstand different cycles, temperature changes on long days and nights would pose an additional problem. Therefore, the cycle should be about the equal to one on Earth. Increasing or decreasing rotation speed is extremely hards, but mirrors could be used to create an artificial day-night cycle.
The process we would use would vary, depending on the object we’re trying to terraform. Most likely the first step would be the creation of atmosphere, which would help with controlling the temperature and allow breathing. If all the required elements for breathable atmosphere are not available, they should be imported from somewhere else. Atmosphere could include strong greenhouse gases, if the object is far from the Sun.
After this we could start transforming the soil to allow the plants to grow. Plants would help with keeping the oxygen and carbon dioxide levels in check, and would also provide food for the settlers. When the atmosphere and the soil would have been transformed, we could start thinking about the ways to solve other problems.
There are multiple objects in our Solar System, that we might be able to terraform in the future. The planets closest to Earth, Venus and Mars, are especially targets of interest. They are located in a zone, where there is plenty of sunlight available and they contain most of the elements needed for life. According to some speculations, Mars might be terraformed with the current technology.
Objects farther in the universe that could be terraformed, are for example, moons of Jupiter and Saturn. Jupiter and Saturn could serve as a place where resources could be brought to the Moons for terraforming. The problem might be the distance from the Sun, so before we are able to terraform these objects, we should find out a way to artificially make them warmer.
If terraforming the planet or object is too hard, we might be able to use technology called paraterraforming to create conditions suitable for life. Its very possible, that we might paraterraform some objects before trying to terraform the completely.
Paraterraforming means, essentially, building of large domes. These domes would rise to heights of many kilometres, and would contain breathable oxygen. Domes would allow a creation of mini-climate, which could be controlled easier than a climate of a whole planet. If its impossible to terraform the whole planet, a planet could be almost completely filled with these domes.
Lack of technology
At the current moment, we’re lacking technology to reliable terraform any object. If we would concentrate our research on terraforming technologies, ways to terraform some planets could be developed quite fast. Controlling the climate is hard, however, as we’re not able to even control the climate on Earth.
Even though terraforming would give us an option to use vast amount of resources, its currently not profitable. Terraforming requires a lot of capital, and there are still resources left on Earth. In the near future, the situation is probably going to change, as we are running out of resources.
We don’t know the composition of possible objects for terraforming well enough. Its possible, that some of them might contain life that we couldn’t even have imagined. Terraforming a planet would most likely kill all these alien lifeforms. Therefore, before terraforming an object, we should be sure that it does not contain life.
Solar System outside of the Earth has usually been defined as neutral area. Through international treaties its common property of the humankind. Problems might arise, when a state or company decides to terraform an object. Would other people also have the right to use resources on the terraformed planet? Before terraforming, agreement with control of the planet should be made.
Terraforming is an interesting concept, that might be used in the future. Terraforming is almost necessary, if we want to ensure survival of humankind in the future, if a catastrophe would destroy the Earth. Terraforming would allow efficient resource harvesting and human survival outside of the Earth.