Artist's conception of a terraformed Mars in four stages of development.

The terraforming (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 those of Earth in order to make it habitable by humans. A planet, as defined by the International Astronomical Union (IAU is a celestial body Orbiting a Star or stellar remnant that is A natural satellite or moon is a Celestial body that Orbits a Planet or smaller body which is called the primary. A hypothesis (from Greek) consists either of a suggested explanation for a phenomenon (an event that is observable or of a reasoned proposal suggesting a possible Temperature and layers The temperature of the Earth's atmosphere varies with altitude the mathematical relationship between temperature and altitude varies among five Temperature is a physical property of a system that underlies the common notions of hot and cold something that is hotter generally has the greater temperature Topography ( topo-, "place" and graphia, "writing" is the study of Earth 's Surface features or those of Planets Ecology (from Greek grc οἶκος oikos, "house(hold" and grc -λογία -logia) is the scientific study of EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001 Planetary habitability is the measure of a Planet 's or a Natural satellite 's potential to develop and sustain Life.

The term is sometimes used more generally as a synonym for planetary engineering. Planetary engineering is the application of Technology for the purpose of influencing the global properties of a Planet. The concept of terraforming developed from both science fiction and actual science. Science (from the Latin scientia, meaning " Knowledge " or "knowing" is the effort to discover, and increase human understanding The term was probably invented by Jack Williamson in a science-fiction story ("Collision Orbit") published during 1942 in Astounding Science Fiction,^[1] but the actual concept pre-dates this work. John Stewart Williamson ( April 29, 1908 – November 10, 2006) who wrote as Jack Williamson (and occasionally under the Pseudonym Analog Science Fiction and Fact is an American Science fiction Magazine. Olaf Stapledon's Last and First Men (1930)^[2] provides a fictional example in which the planet Venus is modified after a long and destructive war with the original inhabitants of the planet. William Olaf Stapledon ( May 10, 1886 &ndash September 6, 1950) was a British philosopher and author of several influential works Last and First Men A Story of the Near and Far Future is a Science fiction novel written in 1930 by the British author Olaf Stapledon. The VENUS ( V ictoria E xperimental N etwork U nder the S ea project is a cabled sea floor observatory operated by the University

Humans currently do not possess the technological or economic means to terraform another planet or moon. Since space exploration is primitive, terraforming techniques remain speculative. Based on experiences with Earth, the environment of a planet can be altered deliberately: however the feasibility of creating an unconstrained planetary biosphere that mimics Earth on another planet has yet to be verified. Mars is considered by many to be the most likely candidate for terraformation. 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. The National Aeronautics and Space Administration ( NASA, ˈnæsə is an agency of the United States government, responsible for the nation's public space program However, a multitude of obstacles stand between the present and an active terraforming effort on Mars or any other world. The long timescales and practicality of terraforming are the subject of debate. Other unanswered questions relate to the ethics, logistics, economics, politics and methodology of altering the environment of an extraterrestrial world. Ethics is a major branch of Philosophy, encompassing right conduct and good life Logistics is the management of the flow of Goods, Information and other resources including Energy and people between the point of origin and the point Economics is the social science that studies the production distribution, and consumption of goods and services. Politics Politics is the process by which groups of people make decisions Methodology (also called manner) is defined as "the analysis of the principles of methods rules and postulates employed by a discipline"

History of scholarly study

Carl Sagan, an astronomer and popularizer of science, proposed the planetary engineering of Venus in a 1961 article published in the journal Science titled, "The Planet Venus. Carl Edward Sagan ( November 9 1934 &ndash December 20 1996) was an American Astronomer, astrochemist, author Science is the Academic journal of the American Association for the Advancement of Science and is considered one of the world's most prestigious Scientific "^[3] Sagan imagined seeding the atmosphere of Venus with algae, which would remove carbon dioxide and reduce the greenhouse effect until surface temperatures dropped to "comfortable" levels. The VENUS ( V ictoria E xperimental N etwork U nder the S ea project is a cabled sea floor observatory operated by the University Algae ( sing. alga are a large and diverse group of simple typically Autotrophic organisms ranging from Unicellular to Multicellular forms Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single The Greenhouse effect refers to the change in the Thermal equilibrium temperature of a planet or moon by the presence of an Atmosphere containing gas that absorbs 3 billion years ago, the Earth had a carbon dioxide atmosphere. Blue-green algae and water evaporation changed the earth's atmosphere into oxygen and nitrogen gas. Cyanobacteria, also known as blue-green algae, blue-green bacteria or Cyanophyta, is a phylum of Bacteria that obtain their energy Later discoveries about the conditions on Venus made this particular approach impossible since Venus has too much atmosphere to process and sequester. The VENUS ( V ictoria E xperimental N etwork U nder the S ea project is a cabled sea floor observatory operated by the University Even if atmospheric algae could thrive in the hostile and arid environment of Venus' upper atmosphere, any carbon that was fixed in organic form would be liberated as carbon dioxide again as soon as it fell into the hot lower regions.

Sagan also visualized making Mars habitable for human life in "Planetary Engineering on Mars," a 1973 article published in the journal Icarus. ICARUS International Journal of Solar System Studies is a premier Scientific journal dedicated to the field of Planetary science. ^[4] Three years later, NASA addressed the issue of planetary engineering officially in a study, but used the term planetary ecosynthesis instead. Planetary ecosynthesis is defined as "the making of a home for life on a planetary scale ^[5] The study concluded that it was possible for Mars to support life and be made into a habitable planet. Planetary habitability is the measure of a Planet 's or a Natural satellite 's potential to develop and sustain Life. That same year 1976, one of the researchers, Joel Levine, organized the first conference session on terraforming, which at the time was called "Planetary Modeling. "

In March 1979, NASA engineer and author James Oberg organized the "First Terraforming Colloquium," a special session on terraforming held at the Lunar and Planetary Science Conference in Houston. James Edward Oberg (born 1944 (often known as Jim Oberg) is an American Space Journalist and Historian, regarded as an expert on Oberg popularized the terraforming concepts discussed at the colloquium to the general public in his 1981 book, New Earths. ^[6] It wasn't until 1982 that the word terraforming was used in the title of a published journal article. Planetologist Christopher McKay wrote "Terraforming Mars," a paper for the Journal of the British Interplanetary Society. The Journal of the British Interplanetary Society ( JBIS) is a technical Scientific journal, first published in 1934. ^[7] The paper discussed the prospects of a self-regulating Martian biosphere, and McKay's use of the word has since become the preferred term. During 1984, James Lovelock and Michael Allaby published The Greening of Mars. Dr James Ephraim Lovelock, CH, CBE, FRS (born 26 July 1919) is an independent scientist author researcher environmentalist and ^[8] Lovelock's book was one of the first books to describe a novel method of warming Mars, where chlorofluorocarbons are added to the atmosphere. Motivated by Lovelock's book, biophysicist Robert Haynes worked behind the scenes to promote terraforming, and contributed the word ecopoiesis to its lexicon. Robert Hall Haynes ( August 27, 1931 &ndash December 22, 1998) was a Canadian Geneticist and Biophysicist. Ecopoiesis is a Neologism created by Robert Haynes. The word was formed from the Greek οικος, house, and ποιησις

Beginning in 1985, Martyn J. Fogg began publishing several articles on terraforming. Year 1985 ( MCMLXXXV) was a Common year starting on Tuesday (link displays 1985 Gregorian calendar) Martyn J Fogg (born July 3 1960 is a widely acknowledged expert on Terraforming. He also served as editor for a full issue on terraforming for the Journal of the British Interplanetary Society in 1991, and in 1995 published the book Terraforming: Engineering Planetary Environments. Year 1991 ( MCMXCI) was a Common year starting on Tuesday (link will display full calendar of the Gregorian Calendar. Year 1995 ( MCMXCV) was a Common year starting on Sunday. Events of 1995 ^[9] Fogg also maintains an active website called The Terraforming Information Pages. ^[10]

Fogg used the following definitions for different aspects related to terraforming:

• Planetary Engineering: the application of technology for the purpose of influencing the global properties of a planet.
• Geoengineering: planetary engineering applied specifically to the Earth. It includes only those macroengineering concepts that deal with the alteration of some global parameter, such as the greenhouse effect, atmospheric composition, insulation or impact flux.
• Terraforming: a process of planetary engineering, specifically directed at enhancing the capacity of an extraterrestrial planetary environment to support life as we know it. The ultimate in terraforming would be to create an open planetary biosphere emulating all the functions of the biosphere of the Earth, one that would be fully habitable for human beings.
• Astrophysical Engineering: taken to represent proposed activities, relating to future habitation, that are envisaged to occur on a scale greater than that of "conventional" planetary engineering.

Fogg also devised definitions for candidate planets of varying degrees of human compatibility:

• Habitable Planet (HP): A world with an environment sufficiently similar to the Earth as to allow comfortable and free human habitation.
• Biocompatible Planet (BP): A planet possessing the necessary physical parameters for life to flourish on its surface. If initially lifeless, then such a world could host a biosphere of considerable complexity without the need for terraforming.
• Easily Terraformable Planet (ETP): A planet that might be rendered biocompatible, or possibly habitable, and maintained so by modest planetary engineering techniques and with the limited resources of a starship or robot precursor mission.

Fogg designates Mars as having been a biologically compatible planet in its youth, but not being in any of these three categories in its present state, since it could only be terraformed with relatively greater difficulty. Mars Society founder Robert Zubrin produced a plan for a Mars return mission called Mars Direct that would set up a permanent human presence on Mars and steer efforts towards eventual terraformation. The Mars Society is an international Space advocacy Non-profit organization dedicated to encouraging the exploration and settlement of Mars. Robert Zubrin (born 19 April 1952) is an American Aerospace engineer and Author, best known for his Advocacy of manned Mars Mars Direct is a proposal for a relatively low-cost manned mission to Mars with current rocket technology ^[11]

The principal reason given to pursue terraforming is the creation of an ecology to support worlds suitable for habitation by humans. Ecology (from Greek grc οἶκος oikos, "house(hold" and grc -λογία -logia) is the scientific study of However, some researchers believe that space habitats will provide a more economical means for supporting space colonization. A space habitat, also called space colony, orbital colony, space city, or space settlement is a Space station intended as a Space colonization (also called space settlement, space humanization, Space habitation, etc If research in nanotechnology and other advanced chemical processes continues apace, it may become feasible to terraform planets in centuries rather than millennia. Nanotechnology, sometimes shortened to nanotech, refers to a field of Applied science whose theme is the control of matter on an Atomic and Molecular On the other hand, it may become reasonable to modify humans so that they don't require an oxygen/nitrogen atmosphere in a 1 g gravity field to live comfortably. Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14 Gravitation is a natural Phenomenon by which objects with Mass attract one another That would then reduce the need to terraform worlds, or at least the degree to which other worlds' environments would need to be altered.

Requirements for sustaining terrestrial life

Main article: Planetary habitability

The only absolute requirement for life is an energy source, but the notion of planetary habitability implies that many other geophysical, geochemical, and astrophysical criteria must be met before the surface of an astronomical body is able to support life. Planetary habitability is the measure of a Planet 's or a Natural satellite 's potential to develop and sustain Life. Of particular interest is the set of factors that has sustained complex, multicellular animals and not merely unicellular organisms on this planet. Research and theory in this regard is a component of planetary science and the emerging discipline of astrobiology. Not only are there planetary requirements, there are theories as to the type and age of the star.

Artist's conception of a terraformed Mars. This realistic portrayal is approximately centered on the prime meridian, 30 degrees north latitude. The Prime Meridian is the meridian (line of Longitude) at which longitude is defined to be 0° Latitude, usually denoted symbolically by the Greek letter phi ( Φ) gives the location of a place on Earth (or other planetary body north or south of the The hypothesized oceans are depicted with sea level at approximately two kilometers below average surface elevation. The kilometre ( American spelling: kilometer) symbol km is a unit of Length in the Metric system, equal to one thousand The ocean submerges what are now Vastitas Borealis, Acidalia Planitia, Chryse Planitia, and Xanthe Terra; the visible landmasses are Tempe Terra at left, Aonia Terra at bottom, Terra Meridiani at lower right, and Arabia Terra at upper right. Vastitas Borealis ( Latin, 'northern waste') is the largest lowland region of Mars. Acidalia Planitia is a Plain on Mars. It is located between the Tharsis volcanic province and Arabia Terra to the north of Valles Chryse Planitia (Greek " Golden Plain " is a smooth circular plain in the northern equatorial region of Mars close to the Tharsis region to the Xanthe Terra is a large area on Mars, centered just north of the Martian equator Tempe Terra is an area in the northern hemisphere of Mars and part of the larger Tharsis region Sinus Meridiani is a feature name for an Albedo feature on Mars stretching east-west just south of that planet's Equator. Arabia Terra is a large upland region in the north of Mars. It is densely cratered and heavily eroded Rivers that feed the ocean at lower right occupy what are now Valles Marineris and Ares Vallis, while the large lake at lower right occupies what is now Aram Chaos. Valles Marineris ( Latin for Mariner Valleys, named after the Mariner 9 Mars orbiter Ares Vallis is a Valley on Mars which appears to have been carved by fluids perhaps Water. Aram Chaos, centered at 26°N 215°W is a heavily eroded Impact crater on the planet Mars.

Photorealistic conception of a terraformed Mars. In the middle is the hypothesized Mariner Bay, currently part of the Mariner Valleys, up in the extreme north part of the Arctic is the Acidalia Planitia Sea. Valles Marineris ( Latin for Mariner Valleys, named after the Mariner 9 Mars orbiter Acidalia Planitia is a Plain on Mars. It is located between the Tharsis volcanic province and Arabia Terra to the north of Valles

Further stages of terraforming

Main article: Ecopoiesis

Once conditions become more suitable to life from Earth, the importation of microbial life could begin. Ecopoiesis is a Neologism created by Robert Haynes. The word was formed from the Greek οικος, house, and ποιησις ^[9] As conditions approach that of Earth, plant life could also be brought in. This would accelerate the production of oxygen, which theoretically would make the planet eventually able to support animal and human life.

Prospective planets

Mars

Main article: Terraforming of Mars

See also: Colonization of Mars

There is some scientific debate over whether it would even be possible to terraform Mars, or how stable its climate would be once terraformed. The terraforming of Mars is the hypothetical process by which the climate, surface and known properties of Mars would be deliberately changed with the goal of making Mars is the focus of much speculation and serious study about possible human colonization which might be possible It is possible that over geological timescales—tens or hundreds of millions of years—Mars could lose its water and atmosphere again, possibly to the same processes that reduced it to its current state. Indeed, it is thought that Mars once did have a relatively Earth-like environment early in its history, with a thicker atmosphere and abundant water that was lost over the course of hundreds of millions of years. The exact mechanism of this loss is still unclear, though several mechanisms have been proposed. The lack of a magnetosphere surrounding Mars may have allowed the solar wind to erode the atmosphere, the relatively low gravity of Mars helping to accelerate the loss of lighter gases to space. A magnetosphere' is a highly magnetized region around and possessed by an Astronomical object. The solar wind is a Stream of charged particles&mdasha plasma &mdashthat are ejected from the upper atmosphere of the Sun. The lack of plate tectonics on Mars is another possibility, preventing the recycling of gases locked up in sediments back into the atmosphere. Plate tectonics (from Greek τέκτων tektōn "builder" or "mason" describes the large scale motions of Earth 's Lithosphere The core of Mars, which is made of mostly Iron, originally held up the magnetic field of Mars. However, once the core cooled down, the magnetic field weakened. The lack of magnetic field and geologic activity may both be a result of Mars' smaller size allowing its interior to cool more quickly than Earth's, though the details of such processes are still unrealized. Re-heating the core of Mars is considered an impractical solution; one only theoretically practical (but still impossible) method would be to hold some sort of giant 'magnifying glass' over the planet to melt it, and possibly re-liquefy the core. However, none of these processes are likely to be significant over the typical lifespan of most animal species, or even on the timescale of human civilization, and the slow loss of atmosphere could possibly be counteracted with ongoing low-level artificial terraforming activities. Terraforming Mars would entail two major interlaced changes: building the atmosphere and heating it. Since a thicker atmosphere of carbon dioxide and/or some other greenhouse gases would trap incoming solar radiation and the raised temperature would put the greenhouse gases into the atmosphere, the two processes would augment one another. Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single Fossil fuels are the best way to increase the temperature on Mars. ^[12]

Venus

Artist's conception of a terraformed Venus. The VENUS ( V ictoria E xperimental N etwork U nder the S ea project is a cabled sea floor observatory operated by the University

Main article: Terraforming of Venus

See also: Colonization of Venus

Terraforming Venus requires two major changes; removing most of the planet's dense 9 MPa carbon dioxide atmosphere and reducing the planet's 500 °C (770 K) surface temperature. Terraforming of Venus is the (theoretical process of engineering the global environment of the planet Venus in such a way as to make it suitable for human habitation The colonization of Venus has been a subject of much speculation and many works of science fiction since before the dawn of Spaceflight, and is still much discussed The VENUS ( V ictoria E xperimental N etwork U nder the S ea project is a cabled sea floor observatory operated by the University The kelvin (symbol K) is a unit increment of Temperature and is one of the seven SI base units The Kelvin scale is a thermodynamic These goals are closely interrelated, since Venus' extreme temperature is due to the greenhouse effect caused by its dense atmosphere. Sequestering the atmospheric carbon would likely solve the temperature problem as well.

Europa (moon)

Europa, a moon of Jupiter, is a potential candidate for terraforming. TemplateInfobox Planet.--> Europa (jʊˈroʊpə; or as One of the advantages to Europa is the presence of liquid water which could be extremely helpful for the introduction of complex life. ^[13] The difficulties are numerous; Europa is in the middle of a huge radiation belt around Jupiter, and a human would die from the radiation within 10 minutes on the surface. This would require the building of massive radiation deflectors, which is currently impractical. Additionally, this satellite is covered in ice and would have to be heated, and there would need to be a supply of oxygen,^[14] though this could, at sufficient energy cost, be manufactured in situ by electrolysis of the copious water available.

Other planets and solar system entities

Artist's conception of what the Moon might look like terraformed, as seen from Earth.

See also: Colonization of the Moon, Colonization of Mercury, Colonization of the outer solar system, and Colonization of Ceres

Other possible candidates for terraformation include Titan, Mercury, Ganymede, Io, Callisto, Luna (Earth's Moon), and even the dwarf planet Ceres. The colonization of the Moon is the proposed establishment of permanent human communities on the Moon. Mercury has been suggested as one possible target for Space colonization of the inner Solar system, along with Mars, Venus, the Moon Some of the moons of the outer planets of the Solar system are large enough to be suitable places for colonization Ceres has been proposed as one possible target for human colonization in the inner Solar system. TemplateInfobox Planet.--> Titan (ˈtaɪtən, or as TemplateInfobox Planet.--> Ganymede (ˈgænɨmiːd, or as Greek TemplateInfobox Planet.--> Io (ˈaɪoʊ, or as Greek TemplateInfobox Planet.--> Callisto (kəˈlɪstoʊ, or as Greek Ceres (ˈsɪəriːz Most, however, have too little mass to hold an atmosphere indefinitely (although it is possible, but not certain, that an atmosphere could remain for tens of thousands of years or be replenished as needed). In addition, aside from the Moon, most of these worlds are so far from the Sun that adding sufficient heat would be much more difficult than even Mars would be. The Sun (Sol is the Star at the center of the Solar System.

Paraterraforming

Also known as the "worldhouse" concept, or domes in smaller versions, paraterraforming involves the construction of a habitable enclosure on a planet which eventually grows to encompass most of the planet's usable area. The enclosure would consist of a transparent roof held one or more kilometers above the surface, pressurized with a breathable atmosphere, and anchored with tension towers and cables at regular intervals. Proponents claim worldhouses can be constructed with technology known since the 1960s. The Biosphere 2 project on Earth proved that it is not quite so simple. Biosphere 2 is a 314-acre (127 ha) structure originally built to be an artificial closed ecological system in Oracle, Arizona ( USA

Paraterraforming has several advantages over the traditional approach to terraforming. For example, it provides an immediate payback to investors; the worldhouse starts out small in area (a domed city for example), but those areas provide habitable space from the start. The domed city is a kind of Urban complex or Space habitat that appears repeatedly in Science fiction. The paraterraforming approach also allows for a modular approach that can be tailored to the needs of the planet's population, growing only as fast and only in those areas where it is required. Finally, paraterraforming greatly reduces the amount of atmosphere that one would need to add to planets like Mars in order to provide Earth-like atmospheric pressures. By using a solid envelope in this manner, even bodies which would otherwise be unable to retain an atmosphere at all (such as asteroids) could be given a habitable environment. Asteroids, sometimes called Minor planets or planetoids', are bodies—primarily of the inner Solar System —that are smaller than planets but The environment under an artificial worldhouse roof would also likely be more amenable to artificial manipulation.

It has the disadvantage of requiring a great deal of construction and maintenance activity. The extra cost might be ameliorated to some degree through the use of automated manufacturing and repair mechanisms. A worldhouse might also be more susceptible to catastrophic failure in the event of a major breach, though this risk can likely be reduced by compartmentalization and other active safety precautions. Meteor strikes are a particular concern in the absence of any external atmosphere in which they would burn up before reaching the surface.

Ethical issues

Main article: Ethics of terraforming

There is a philosophical debate within biology and ecology as to whether terraforming other worlds is an ethical endeavor. The ethics of terraforming has constituted a philosophical debate within Biology, Ecology, and Environmental ethics as to whether Terraforming On the pro-terraforming side of the argument, there are those like Robert Zubrin, Martyn J. Fogg, and Richard L. S. Taylor who believe that it is humanity's moral obligation to make other worlds suitable for life, as a continuation of the history of life transforming the environments around it on Earth. Robert Zubrin (born 19 April 1952) is an American Aerospace engineer and Author, best known for his Advocacy of manned Mars Martyn J Fogg (born July 3 1960 is a widely acknowledged expert on Terraforming. Richard Lionel Sidney Taylor is the author of "Moon Maps" and a leading supporter of Terraforming other planets ^[15][16] They also point out that Earth would eventually be destroyed if nature takes its course, so that humanity faces a very long-term choice between terraforming other worlds or allowing all terrestrial life to become extinct. In any case, terraforming totally barren planets, it is asserted, is not morally wrong as it does not affect any other life. Some more cautious thinkers believe terraforming would be an unethical interference in nature, and that given humanity's past treatment of the Earth, other planets may be better off without human interference. Still others strike a middle ground, such as Christopher McKay, who argues that terraforming is ethically sound only once we have completely assured that an alien planet does not harbor life of its own; but that if it does, while we should not try to reshape the planet to our own use, we should engineer the planet's environment to artificially nurture the alien life and help it thrive and co-evolve (or even co-exist with humans). Christopher McKay can refer to Christopher McKay (planetary scientist, planetary scientist at NASA Ames Research Center Christopher McKay (footballer ^[17]

Economic issues

The initial cost of such projects as planetary terraforming would be gargantuan, and the infrastructure of such an enterprise would have to be built from scratch. Such technology is not yet developed, let alone financially feasible at the moment. John Hickman has pointed out that almost none of the current schemes for terraforming incorporate economic strategies, and most of their models and expectations seem highly optimistic. ^[18] Access to the vast resources of space may make such projects more economically feasible, though the initial investment required to enable easy access to space will likely be tremendous (see Asteroid mining, solar power satellites, In-Situ Resource Utilization, bootstrapping, space elevator). Raw resources and minerals could be mined from an Asteroid in space using a variety of methods A solar power satellite, or SPS or Powersat, as originally proposed would be a Satellite built in High Earth orbit that uses Microwave In Space exploration, In-Situ Resource Utilization (ISRU describes the proposed use of resources found or manufactured on other planetary bodies (the Moon Mars etc This is the history of bootstrapping or booting which began in the 1880s as a leather strap and evolved into a group of metaphors that share a common meaning a self-sustaining A space elevator is a proposed structure designed to transport Material from a celestial body 's Surface into space.

Some advocates of space colonization have argued that the same financial investment required to terraform Mars or Venus could produce a larger area of "land" if used to build space habitats instead. Space colonization (also called space settlement, space humanization, Space habitation, etc A space habitat, also called space colony, orbital colony, space city, or space settlement is a Space station intended as a They argue that a civilization that knows how to live in space can survive anywhere in the solar system, whereas terraforming Mars will only help us to live in one place. Some view terraforming as planetary chauvinism. Planetary chauvinism is a term coined by Isaac Asimov to describe a belief held by certain individuals that human society will be planet based rather than space-based despite

Political issues

Further information: Outer Space Treaty

There are many potential political issues arising from terraforming a planet, such as who gets to own the extraterrestrial land on the new planet, with contenders being national governments, trans-national organizations like the United Nations, Corporations or individual settlers themselves. Key points of the Treaty The Outer Space Treaty represents the basic legal framework of international space law The United Nations ( UN) is an International organization whose stated aims are to facilitate cooperation in International law, International security Such settlements may become part of national disputes as countries try to make parts of other planets part of their own national territory. Rivalries between nations continue to be a primary motivation for shaping space projects. ^[19]

Popular culture

Main article: Terraforming in popular culture

Terraforming is a common concept in science fiction, ranging from television, movies, novels and video games. Terraforming has been well-represented in Popular culture, usually in the form of Science fiction. The concept of changing a planet for habitation precedes the use of the word 'terraforming', with H. G. Wells describing a reverse-terraforming, where aliens in his story The War of the Worlds change Earth for their own benefit. Herbert George Wells (21 September 1866 &ndash 13 August 1946 He was an outspoken socialist and a pacifist, his later works becoming increasingly political The War of the Worlds (1898 by H G Wells, is an early Science fiction Novel which describes an invasion of England by Also, Olaf Stapledon's Last and First Men (1930) provides the first example in fiction in which Venus is modified, after a long and destructive war with the original inhabitants, who naturally object to the process. William Olaf Stapledon ( May 10, 1886 &ndash September 6, 1950) was a British philosopher and author of several influential works Last and First Men A Story of the Near and Far Future is a Science fiction novel written in 1930 by the British author Olaf Stapledon. Recent works involving terraforming of Mars includes the novels in the Mars trilogy, by Kim Stanley Robinson. Kim Stanley Robinson (born March 23 1952) is an American Science fiction Writer, probably best known for his award-winning

Terraforming has also been explored on television and in feature films, most prominently and famously in the Star Trek universe. In the Star Trek movie The Wrath of Khan, the film's antagonist Khan steals the "Genesis device", a device developed to quickly terraform barren planets, and wields it as a weapon. Star Trek II The Wrath of Khan is the second feature film based on the Star Trek Science fiction Television series, following In the fictional Star Trek universe Project Genesis was a process of rapidly Terraforming worlds to make them suitable for settlement and food production A similar device exists in the animated feature film Titan A.E. which depicts the eponymous ship Titan, capable of creating a planet. Titan AE is a 2000 Post-apocalyptic animated science fiction Adventure film from Fox Animation Studios

Also in the Star Trek universe, humans terraformed Mars in the 22nd century by redirecting comets towards Mars' north and south poles. In the episode "Terra Prime" the Enterprise crew uses one of the comets to avoid being detected by the antagonist. "Terra Prime" is the title of the penultimate Star Trek Enterprise television episode from its final season

In Joss Whedon's short-lived hit television series Firefly, and its feature film sequel Serenity, giant "terraformers" (ships or factories designed to generate atmosphere and perform other functions of terraforming) were used to transform the ecosystems of dozens of planets and hundreds of moons across a huge solar system into human-livable environments. Firefly is an American Science fiction Television series created by writer/director Joss Whedon, creator of Buffy the Vampire Slayer Serenity is a 2005 space western Film written and directed by Joss Whedon.

It is shown in the movies Alien and Aliens. Alien is a 1979 science fiction / Horror film directed by Ridley Scott and starring Sigourney Weaver. This article is about the film for the video games see Aliens (Square computer game and Aliens (arcade game. In the first film, the atmosphere of LV-426 is unbreathable and John Hurt's character must wear an environment suit; 60 years later an atmospheric factory has been utilized to withdraw sulphur and replace it with oxygen; producing a stormy but breathable atmosphere. LV-426 is a fictitious planetoid appearing in the films Alien (1979 and Aliens (1986 John Vincent Hurt, CBE (born 22 January 1940 is an English Actor.

In the anime Cowboy Bebop humanity has terraformed dozens of moons and planets after a hyperspace gate accident fractured the Moon, raining debris on Earth. is a Japanese animated television series. Directed by Shinichirō Watanabe and written by Keiko Nobumoto, Cowboy Bebop was produced by Asteroids have also been colonized to sustain human life. Also, the manga and anime series Aria takes place on a terraformed Mars. is a Science fiction Manga by. The series was originally titled when it was published by Enix in the magazine Monthly Stencil, being retitled when In Dragon Ball Z movie 4, the evil "Lord Slug" terraforms the Earth to make it suitable for his soldiers and to kill humanity. Lord Slug redirects here For the character in the film see List of extraterrestrials in Dragon Ball Dragon Ball Z Lord Slug, known As well as the video game Armored Core 2, which takes place on a newly terraformed Mars. Armored Core 2 is a Mecha video game in the Armored Core series

In Stargate SG1 episode "Scorched Earth" an alien ship terraforms a planet recently inhabited by Enkarans with the help of humans. Season four of Stargate SG-1, an American - Canadian Television series, began airing on June 30, 2000 on This is a list of the human civilizations featured in the television series Stargate SG-1. The movie Blade Runner alludes to the existence of "Off-World Colonies" which are advertised as having a more suitable living atmosphere than the polluted Earth: the story is based on the escape of individuals designed as labor forces for the new colonists. Blade Runner is a 1982 American Science fiction Film, directed by Ridley Scott. In the movie Total Recall an alien device is activated to transform the atmosphere of Mars, while in Red Dwarf, the crew have to rescue Rimmer from a planet terraformed to match his own disturbed sub-conscious. Total Recall is a 1990 Academy Award -winning American Science fiction film. According to the Hertzsprung-Russell diagram, a red dwarf star is a small and relatively cool Star, of the Main sequence, either late K Arnold Judas Rimmer BSC SSC is a Fictional character in the Science fiction Situation comedy Red Dwarf, played by Chris

In the movie Red Planet humanity has partially terraformed Mars by putting algae on the planet's surface. For the unrelated novel by Robert A Heinlein see Red Planet (novel. As a result, the crew that crash lands on Mars can breathe. Also, in the Halo series there exist multiple colony planets that were made suitable for human habitation through terraforming. Halo is a Science fiction Video game franchise created by Bungie and owned and published by Microsoft Game Studios.

On the tv series Futurama (set 1000 years in the future) in the episode Mars University it is discovered that mars in the year 3000 is habitable, and there is a university there. Futurama is an Emmy Award -winning animated American sitcom created by Matt Groening, and developed by Groening and " Mars University " is episode eleven of the first production season of Futurama. It is discussed that when Mars University was established, they planted "traditional college foliage" including Trees and Hemp and that soon after the whole planet was Terraformed . A tree is a perennial Woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or This article is about the cultivation and uses of industrial hemp not its psychoactive cousin Cannabis (drug. There are also native Martians, who are revealed in the episode Where the Buggalo Roam. "Where the Buggalo Roam" is the tenth episode in season three of the animated television series Futurama. The Martians however, sold their land to a Chinese man named Sir Reginold Wong for a single bead (an enormous diamond)- a play on the sale of the isle of Manhattan.

David Gerrold's currently incomplete novel series The War Against The Chtorr takes a twist with the terraforming concept and has the Earth being invaded by unseen an alien species which is Chtoraforming the Earth to match their own world. David Gerrold, born Jerrold David Friedman ( January 24, 1944) in Chicago Illinois, is a Science fiction author who started his career The War Against the Chtorr is a series of novels written by David Gerrold. The species from Chtorr are estimated to be a half a billion years older than those on Earth, and thus evolved to a higher level of competition and trickery. The Earth's species are steadily losing the battle as they are unable to compete. Humans are steadily losing the battle, as well, as the different species interfere with and overpower their best technologies which they are not designed to work against.

See also

• Planetary habitability
• Globus Cassus
• Extrasolar planets
• Project Genesis
• Weather control
• Space colonization
• Futurology
• Megascale engineering

References

External links

• Red Colony
• New Mars forum
• Terraformers Society of Canada
• Visualizing the steps of solar system terraforming
• Research Paper: Technological Requirements for Terraforming Mars
• Terraforming
• The Terraforming Information Pages
• The Terraforming of Worlds
• Terraformation de Mars