Extraterrestrial environments are earthly
Taken literally, the concept is to gradually improve the alien planet into an Earth-like living environment, and humans consciously transform a potentially habitable star into an Earth-like atmosphere, temperature, surface landform or ecological structure to suit future human habitation. If a planet becomes the interstellar colonization of future humans, then the earthliness of the alien environment will surely be realized. But is humanity's ultimate dream to reproduce and colonize the entire galaxy? How will this be achieved? Theoretically divided into two parts, the first part is ecological synthesis, which transfers life on Earth to a disintegrated alien ecological environment, with the purpose of accelerating the restoration of the ecological environment; the second part is topographic suitability, building a habitable walled site on an alien planet, and eventually countless such walled living bases are spread across the planet.
Terraforming is a planetary project in which the surface environment of a celestial body is artificially altered to make its climate, temperature, and ecology similar to that of the Earth's environment. Sometimes the term is used to refer to planetary engineering. The idea of earthliness is rooted in science fiction and real science. The coin created for the word was probably Jack Williamson, in a novel published in the journal Astounding Science Fiction in 19421. But the concrete idea of terraformization predates this. Olaf Stapledon's 1930 Last and First Man tells the story of a long war against the primitive inhabitants of Venus who opposed terraformisation.
Basic content
Space exploration is still in its infancy, and many plans for earthization are still in the envision stage. From what we know about our own world, it is feasible for human influence to alter the natural environment, although the feasibility of building an Earth-like biosphere on another planet that is not controlled by nature has yet to be proven. Many people think that Mars is the most viable candidate for terraformization. There has been a lot of research on heating the surface of Mars and changing its atmospheric composition, and NASA has even chaired a debate about it. However, there is still a big gap between now and other celestial bodies such as actively terraforming Mars. The length of time it will take to terraform and its possibilities remain to be explored. Other issues waiting to be addressed include ethical, logistics management, economic, political considerations, and specific ways to change the environment of the world beyond the earth.
Astronomer and popular science writer Carl Sagan published an article in a scientific journal in 1961 titled Planet Venus, proposing planetary engineering for Venus. Sagan envisions spreading algae through Venus' atmosphere to absorb carbon dioxide, thereby reducing the greenhouse effect until the surface temperature drops to "moderate." 3 billion years ago, the Earth's atmosphere was also dominated by carbon dioxide, and later hydrogen and oxygen components appeared due to the evaporation of blue-green algae and water. Later observations found that due to the mass of Venus's atmosphere, it was impossible to change it with algae. Even if algae are found to survive in Venus's harsh, dry outer atmosphere, they will be oxidized into carbon dioxide by falling from carbon dioxide-fixed organic matter to the hot inner atmosphere.
In 1973, Sagan published an article in Icarus magazine titled "Planetary Engineering on Mars" discussing the possibility of making Mars habitable,[4] Three years later, a NASA research project formally addressed the issue of planetary engineering, but by the name planet ecosynthesis. The conclusion is that there are currently no known obstacles to modifying Mars to make it a habitable planet capable of sustaining life. That same year, Joel Levine, a scientist on the research project, organized the first scientific conference on earthliness (then known as "planetary simulations").
In March 1979, NASA engineer and author James Oberg organized the first "Symposium on Earthization" at the Lunar and Planetary Science Conference in Houston. In 1981, he wrote the ideas raised at the conference into a popular book, New Earth. In 1982, planetary scientist Christopher McKay published an article in the British Planetary Society Journal titled "Terraforming Mars", the first time the term "terraforming" was used in a formal scientific publication. The article discusses the Martian biosphere with self-regulation. In 1984, James Lovelock and Michael Allaby published a book titled "Greening Mars",[8] which first proposed ways to add hydrocarbons to the Martian atmosphere to heat Mars.
Since 1985, Martyn J. Fogg has published several articles on earthliness, edited a 1991 special edition of the British Planetary Society Journal, and wrote a book in 1995, "Geochemistry: Environmental Engineering for planets". He also has a website dedicated to geochemistry for geodescibility information.
Fogg uses the following terms to distinguish between different aspects of globalization:
Planetary Engineering: Using technology to influence the overall properties of a planet.
Geoengineering: Planetary engineering specifically for earth, but only includes processes that affect the world, such as changing global warming, atmospheric composition, etc.
Geoscience: Planetary engineering is used to alter the environment of an extraterrestrial planet to enable it to support life. The ultimate goal is to create an environment that operates autonomously, simulates the full function of the Earth's biosphere, and is perfectly suitable for human habitation.
Astrophysical Engineering: A more extensive range of habitable works than planetary engineering.
He also proposed the following classifications that distinguish between human habitability:
Habitable Planets: Planetary environments similar to Earth's, which can support the comfortable and free survival of humans.
Biologically Viable Planets : The physical environment on the planet's surface allows organisms to multiply. If such planets themselves have no life, they can change the environment by introducing organisms without the need for terraformization.
Easy-to-earth planets: Without the need for a large number of starships or robotic resources, small-scale planetary engineering can be turned into biologically viable planets.
Fogg believes that Mars was a pre-earth planet in its early years, but its current environment is very difficult to earthize. However, Mars is the most suitable for earthization near Earth. Robert Zubrin, founder of the Mars Society, had developed a plan for humans to permanently settle mars and eventually terraform.
The main purpose of globalization is to establish an ecological environment suitable for human habitation. But some researchers claim that the space station is the right means of space colonization from an economic point of view. Of course, if nanotechnology and other chemical technologies continue to advance rapidly, the process of terraforming could accelerate from taking decades to centuries. But in turn, these technologies can also be used to alter human physiology so that people can survive comfortably without relying on the oxygen/nitrogen atmospheric composition and gravity of the earth today. These changes will reduce the need for geo-transformation or make it easier.
In fact, there is only one minimum requirement for maintaining life - energy source. However, there are many geographical, geochemical, and astrophysical requirements for a planet to be habitable, especially to allow complex multicellular, rather than just single-celled organisms, to survive.