Terraforming

Terraforming or Earth-shaping is the hypothetical process of deliberately modifying the atmosphere, temperature, surface topography or ecology of a planet, moon, or other astronomical body to be similar to the environment of Earth, with the goal of making it habitable for humans. The concept of terraforming developed from both science fiction and actual science. The term was coined by Jack Williamson in the science-fiction short story "Collision Orbit" in Astounding Science Fiction in 1942. American astronomer Carl Sagan later gave one of the first scientific propositions of terraforming with the planetary engineering of Venus in 1961. 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. While Venus and the Moon have been studied in the subject of terraforming, 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 for the terraforming of Mars may be within humanity's technological capabilities, but according to Martin Beech, the economic attitude of preferring short-term profits over long-term investments will not support a terraforming project. The long timescales and practicality of terraforming are also the subject of debate. As the subj