The word ''terraforming'' conjures up many exotic images and p-
hapsevenwildemotions, butatitscoreitencapsulatestheideathat
worldscanbechangedbydirecthumanaction.Theultimateaimof terraforming is
to alter a hostile planetary environment into one that is Earth-like,
and eventually upon the surface of the new and vibrant world that you or
I could walk freely about and explore. It is not entirely clear that
this high goal of terraforming can ever be achieved, however, and
consequently throughout much of
thisbooktheterraformingideasthatarediscussedwillapplytothe goal of
making just some fraction of a world habitable. In other cases,
theterraformingdescribedmightbeaimedatmakingaworld
habitablenotforhumansbutforsomepotentialfoodsourcethat, of course, could
be consumed by humans. The many icy moons that reside within the Solar
System, for example, may never be ideal locationsforhumanhabitation,
buttheypresentthegreatpotential for conversion into enormous hydroponic
food-producing centers. The idea of transforming alien worlds has long
been a literary backdrop for science fiction writers, and many a
make-believe planet has succumbed to the actions of direct manipulation
and the indomitable grinding of colossal machines. Indeed, there is
something both liberating and humbling about the notion of tra- forming
another world; it is the quintessential eucatastrophy espoused by J. R.
R. Tolkien, the catastrophe that ultimately brings about a better world.
When oxygen was first copiously produced by cyanobacterial activity on
the Earth some three billion years ago, it was an act of extreme
chemical pollution and a eucatastrophy. The original life-nurturing
atmosphere was (eventually) changed f- ever, but an atmosphere that
could support advanced life forms came about.
