Terraforming a celestial body is possible only if we provide the correct amounts of minerals.
Overall[]
Life, as we know it, depends on a big number of minerals, that must be in the correct amount. Extremophiles can survive in harsh environment, but majority of plants and animals will require a certain ground, air and water composition. The lack or excess of certain elements can be a big problem. Some chemical compounds are also of high importance, while others are extremely toxic.
For example, on Titan, the global underground ocean was found to be as salty as Dead Sea [1]. The ocean of Enceladus is also found to contain salts, but the geysers show that it is not as salt [2]. If we want to terraform titan, we have to do something with the excess of salt.
Possible solutions[]
Pioneers will have to do something to make their new worlds better homes. On Earth, similar processes were done in some places.
Sequestration is the process that moves an element or a molecule into a place where it can be deposited without affecting the environment. For example, carbon dioxide might be separated into oxygen and carbon. The excess of carbon can then be deposited on the ocean seabed, where it cannot ignite.
Transformation is a process that changes structure of a substance. For example, chrome V is soluble in water and is dangerous for the environment. Chrome IV is not soluble and so it will not affect living organisms. Iapetus contains hydrogen cyanide, toxic for life. this substance can be transformed into something less dangerous.
Natural transformation will occur once the terraforming process goes on. When temperature gets to a new value, many chemical compounds will transform or interact. in the same way, once we add oxygen to an atmosphere, it can oxidation reactions will take place slowly or violent, transforming many potentially dangerous molecules. On the other hand, new potentially toxic chemicals might get formed.
Evacuation will require moving dangerous compounds away from the planet. It might be useful for substances that are in small amounts and can be easy separated.
Insertion is the process that allows new substances to be inserted to the planet. For Luna or Mercury, it was proposed to bring water by diverting comets. The same process can be used to bring to a planet (or to a region of a planet) microelements needed for life.
Replacement is a local process, that requires mining for a selected microelement and bringing it to surface. In the same time, other substances can be inserted deep underground. This process might have lower costs then insertion.
Costs and timeline[]
Depending on planet, these costs might be less then 1% or up to 50% of entire terraforming costs. The steps that are most probable to be followed, are these ones:
- Creating the best mineral composition maps. First of all, a geological research needs to be done, in order to get as much information as possible about the planet.
- Then, some substances need to be evacuated or sequestrated immediately. For example, if we detect a crater full with cadmium and scientists argue that the crater will meltdown and all cadmium will get into the new seas, it must be removed before any other action.
- When the main phases of terraforming are going on (changing the temperature, modifying atmosphere, adding first forms of life), pioneers must keep an eye on possible dangers. Some of them might be predicted, some not. For example, from ground probes, scientists might know that a certain ice layer contains dioxin, so that a treatment facility can be built when water from that ice melts, it will be clean.
- Once the environment is almost changed, scientists will have an average view of how the future planet will look like. So, they will start bringing those microelements that are missing. For those in excess, a special chemical treatment is needed. Once this is done, plants and later animals can be added to create an ecosystem.
- After terraforming process has ended, problems will still exist. Underground water might extract toxins from the rocks. Also, some unpredicted chemical transformations might occur in the new environment.
Pioneers will have many options. They could do the minimum work for the new planet, leaving the rest to future generations. Or, they could do their best, creating a better world for their children.
Terraforming process is probably the most ambitious thing humans will ever try to do. It will require high and complex knowledge and will always be full of surprises. There is no universal model. Each celestial body has to be treated separately.