Kim Stanley Robinson is the author of this Nebula & Hugo Award-winning trilogy. Green Mars won the Hugo for best SF novel for 1994. It continues the story of humans settling the planet by "terraforming" it, with development of an underground and the problems of forming a new society. (For his books I’ve read, click on his name.)

The transformation of Mars from a barren red planet to a life-sustaining green planet was expected to take much time. They realize that “aeroformation” must come before “terraformation” in order to make the air on Mars breathable and the surface warmer with lakes and oceans nstead of ice and glaciers. A new generation of children born on Mars has come to young adulthood at the beginning of Green Mars. To them, Earth is known only by what they hear from their parents – the many survivors of the First Hundred. Robinson develops the characters of these young “Martians” (who are much taller and have fully adapted to Mars weaker gravity and colder temperatures than did many among the First Hundred). Naturally they strongly favor complete freedom from Earth, which has failed to solve its major problem of overpopulation. Earth has become so overcrowded that they want to send huge numbers of people to live on Mars. Both generations on Mars strongly oppose this and some feel that to avoid a major war with Earth they must accept a very limited number of immigrants from Earth. The First Hundred have developed drugs that will extend their lifetimes by 100 years or more, so they are as active as they were in Red Mars, but now both teach and learn to live with the new generation.

Publishers Weekly gives a concise summary of Green Mars, which I repeat here: “The sequel to Red Mars details an early 22nd-century Mars controlled by Earth's metanationals, gigantic corporations intent on exploiting Mars. Debate among the settlers--some native-born, some the surviving members of the First Hundred--is divided between the minimalist areoformists, who have come to love Mars in all its harshness, and the terraformists, who want to replicate Earth. As the surface of Mars warms and is seeded with genetically altered plants, the settlers await Earth's self-destruction, which they hope will give them a chance to claim their independence. They travel endlessly over every inch of Mars--no mean feat, since most of the First Hundred are criminals wanted for their roles in the failed revolt of 2061--with each kilometer and each group of settlers they meet described in laborious detail. When they're not traveling, these colonists contemplate the history of which they have been a part and which they can only partially recall as a result of their longevity treatments. With the collapse of Earth society and internecine battles among the metanationals, the Martian settlers liberate their cities and declare their planet free. This wide-ranging novel is loaded with all manner of scientific and historical detail, but the story bogs down under its very breadth and seems almost like a Martian year--twice as long as it needs to be.”

But I disagree with Publishers Weekly’s opinion of “laborious detail” and I did not feel that “the story bogs down” at all – I think its breadth is quite necessary in order for Kim Stanley Robinson to develop adequately the cast of characters, for some of the old characters have changed. The new generation is a lively bunch – they do more than just help to keep this epic saga exciting, for they are “Martians” not colonists from Earth.