If the Colonization of Other Worlds is not to be restricted to those that prove almost-exact duplicates of the Earth, some form of adaptation will be necessary; the colonists might adapt themselves by Genetic Engineering, as in James Blish's Pantropy series, or cyborgization (see Cyborgs), as in Frederik Pohl's Man Plus (1976), but if they are bolder they might instead adapt the worlds, by terraforming them. The term was coined by Jack Williamson in the series of stories revised as Seetee Ship (July and November 1942, January-February 1943 Astounding; fixup 1951; magazine stories and early editions as by Will Stewart), where it is used in a minor subplot, but such a project had earlier been envisaged in Olaf Stapledon's Last and First Men (1930), where Venus is prepared for human habitation by electrolysing water from its oceans to produce oxygen. Stapledon's project was primitive (and unworkable); most sf stories envisage plant life being used to generate a breathable atmosphere on terraformable planets, just as it once did on Earth.
As it gradually became accepted that the other planets in the solar system could not sustain human life, terraforming projects became commonplace in sf, especially in relation to Mars. Stories like Arthur C Clarke's The Sands of Mars (1951) and Patrick Moore's series begun with Mission to Mars (1956) envisage relatively small-scale modifications, but, as the true magnitude of the problem has become apparent, writers have been forced to imagine much more complex processes. Ian McDonald's Desolation Road (1988) tends to the frankly miraculous, but compensates with some memorable imagery; its echoes of Ray Bradbury seem slightly more appropriate than the echoes of Edgar Rice Burroughs in The Barsoom Project (1989) by Larry Niven and Steven Barnes. In the real world, however, people have been hatching long-term plans ever since the idea of terraforming was first treated seriously by such nonfiction popularizations as Carl Sagan's The Cosmic Connection (1973) and Adrian Berry's The Next Ten Thousand Years (1974). Kim Stanley Robinson has elaborated a trilogy of novels following his novella Green Mars (September 1985 Asimov's; 1988 dos), which endeavours to describe a realistic series of procedures: Red Mars (1992), Green Mars (1993) – no connection to the novella – and Blue Mars (1996).
Other writers have followed Stapledon in imagining the terraforming of Venus, among them Poul Anderson in "The Big Rain" (October 1954 Astounding) and "Sister Planet" (May 1959 Satellite). This project has recently become the subject of an ambitious and extensive series by Pamela Sargent, begun in Venus of Dreams (1986) and continued in Venus of Shadows (1988).
The only other worlds in the solar system which seem to be plausible candidates for terraforming are some of the satellites of Jupiter and Saturn (see Outer Planets). Ganymede is the favourite, featuring in Robert A Heinlein's Farmer in the Sky (1950), Poul Anderson's The Snows of Ganymede (Winter 1955 Startling; 1958 dos) and Gregory Benford's Jupiter Project (1975). Jack Vance's "I'll Build Your Dream Castle" (September 1947 Astounding), about custom-terraformed Asteroids, is decidedly tongue-in-cheek.
The unlikely prospect of terraforming the Moon is referenced in Arthur C. Clarke's Far Future take "Transience" (July 1949 Startling), which mentions that humans "had torn down its mountains and brought it air and water." Gene Wolfe's The Book of the New Sun (1980-1983 4vols) similarly indicates in passing that this era's the Moon has long sustained forests and other vegetation, and so appears green. Stephen Baxter's Moonseed (1998) features rapid-action terraforming or at least oxygenation of the Moon to provide an emergency bolt-hole from this book's Disaster-afflicted Earth.
The idea that the terraforming of worlds might be reduced to a matter of routine as humanity builds a Galactic Empire is occasionally featured in sf novels, although generally as a throwaway idea. Elaborate descriptions of terraforming in such a context are rare, but David Gerrold's Moonstar Odyssey (1977) and Andrew Weiner's Station Gehenna (1987) both involve terraforming projects whose methods are more-or-less scrupulously sketched out. Some of Roger Zelazny's works assume that terraforming projects can be so routinized that "worldscaping" might become a kind of art form; his Isle of the Dead (1969) features a protagonist who is in this godlike line of work, with many finished worlds to his credit. The same notion surfaces in Robert Sheckley's Dimension of Miracles (1968), in Douglas Adams's Hitch Hiker series (with the planet-builders of Magrathea) and in the film Time Bandits (1981) directed by Terry Gilliam, and technologically powerful worldmakers with a mischievous bent hover (unfathomably) in the background of Terry Pratchett's Strata (1981). It is probable, though, that it is the realistic treatments of Sargent and Robinson which will set the pattern for the most significant future uses of the theme in sf. Jack Williamson offers a logical twist in Terraforming Earth (2001), whose title describes the lengthy post-Disaster operations after an Asteroid impact has wiped out most of humanity and triggered a new Ice Age.
On a more grandiose scale, some stories feature radical transformation of the universe as a whole to render it more hospitable to some particular form of life, either by gradual reshaping or by radical Time-Travel intervention in the formation of the universe (see Alternate Cosmos). Thus Frederik Pohl's Heechee sequence introduces the dread foes the Assassins, who have retreated to sanctuary in a form of Black Hole after setting in motion mechanisms intended to change the universal constants of Physics: the motive proves to be the making of a universe better suited to Uploaded intelligence, which will benefit humanity when we too have made this transition. Less comfortably, the photino birds of Stephen Baxter's Xeelee saga are changing things to benefit their own non-baryonic life, as distinct from the familiar baryonic matter which is the substrate of our own and other Aliens' Biology. The time-travel approach features in Baxter's Wellsian The Time Ships (1995), producing a new and supposedly better Alternate Cosmos. [MJE/BS/DRL]
see also: Moon; Xenoforming.
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