Terraforming is the process of changing the environment of a planet to make it more like Earth. Many scientists have proposed terraforming Mars as a way of dealing with over-crowding on Earth. Nobody knows exactly how terraforming would work, and whether it would have a damaging effect on Mars’ natural environment, but in theory, Mars could be transformed into a second Earth, where many forms of life could live naturally. The diagrams to the right show how it could be done.
Terraforming or terraformation (literally, “Earth-shaping”) of a planet, moon, or other body is the hypothetical process of deliberately modifying its atmosphere, temperature, surface topography or ecology to be similar to the environment of Earth to make it habitable by Earth-like life.
The concept of terraforming developed from both science fiction and actual science. The term was coined by Jack Williamson in a science-fiction short story (“Collision Orbit”) published during 1942 in Astounding Science Fiction, but the concept may pre-date this work.
Even if the environment of a planet could be altered deliberately, the feasibility of creating an unconstrained planetary environment that mimics Earth on another planet has yet to be verified. Mars is usually considered to be the most likely candidate for terraforming. Much study has been done concerning the possibility of heating the planet and altering its atmosphere, and NASA has even hosted debates on the subject. Several potential methods of altering the climate of Mars may fall within humanity’s technological capabilities, but at present the economic resources required to do so are far beyond that which any government or society is willing to allocate to it. The long timescales and practicality of terraforming is the subject of debate. Other unanswered questions relate to the ethics, logistics, economics, politics, and methodology of altering the environment of an extraterrestrial world.
