Terraforming or terraformation (literally, “Earth-shaping”) of a planet, moon, or other body is the theoretical process of intentionally altering its atmosphere, temperature, surface topography, or ecology to be the same as the atmosphere of Earth to make it habitable by Earth-like life.
In our previous articles, we have discussed different ways we could employ to terraform the moon, the Sun, and Ceres.
Today, let’s explore how exactly we could terraform Mercury.
Mercury would be a hard planet to terraform (not as hard as Venus, though). It has many characteristics that are decisive for terraforming, including a lower surface gravity (similar to Mars), an inner dynamo that generates a magnetic field (which is particularly vital as a radiation guard so close to the hot Sun), and many stores of organic compounds and water-ice in its mysterious polar craters.
Humans could build initial habitats mostly underground to install a continuous human presence on the planet before final terraforming. However, the colonies’ above-ground would need to be pressurized and self-contained, similar to a space station. This is because Mercury’s surface pressure is close to zero due to proximity to the Sun and its low gravity.
Terraforming Mercury –
Completely terraforming Mercury would require first protecting the planet from dangerous solar radiation before commencing the installation of an atmosphere on Mercury. Mercury’s natural magnetic field is 1/100th of Earth’s. This is tiny; however, if only considering Mercury’s magnetic field and low gravity, Mercury should have an atmosphere similar in thickness to our next-door neighbor, Mars. However, Mercury’s proximity to the Sun means that it encounters a much more intense solar wind pressure, three times greater than that faced by our Earth. The extreme solar wind has barred Mercury from incorporating an atmosphere thick enough to be suitable to humans.
This is why creating an atmosphere would only be achievable once a proper shielding unit (such as cosmic solar shades) has thrown some of the solar radiation pressure away from Mercury’s surface. There is a chance that harmful gases from the solar wind would start accumulating to form a thin atmosphere around Mercury. Still, future human terraformers would want to properly thicken that atmosphere to make the planet’s surface more healthy for future colonists.
Unlike Mars, which carries frozen gases locked up inside the valleys across its surface, Mercury’s rocks’ gaseous components have long been wholly baked away. Gases to create an atmosphere would have to be brought to Mercury from elsewhere in the Solar System. Since excess heat is a significant obstacle for a planet so close to the Sun, greenhouse gases like carbon dioxide or methane would have to be kept to a bare minimum. Nitrogen for Mercury’s new atmosphere could come from Jupiter’s Titan. Future humans could redirect icy comets to Mercury to flood craters with water to form seas. An abundant supply of oxygen would be needed, which could come from the water’s oxygen and hydrogen.
These are the steps needed to terraform Mercury.