Third in Robinson's hitherto stunning Martian trilogy (Red Mars, 1993; Green Mars, 1994). The terraforming of Mars proceeds, though, at the insistence of angry, isolationist Reds, more slowly; oceans, plants, and animals proliferate, while modified humans are able to live unprotected on the surface. As an amazingly diverse set of social systems evolves, the Martians buckle down to inventing a new and appropriate form of government. With the available longevity treatments, the population of Earth is soaring, raising the pressure to allow greater and more rapid immigration to Mars. Meanwhile, the invention of new propulsion units has opened up the outer solar system to development and colonization; even starships are now feasible. Those of the original Martian First Hundred that survive—a score or so—are all well over two hundred years old, experiencing memory problems and facing sudden, symptomless death. Many of the characters who were once bitter enemies—Red fanatic Ann, scientist Sax with his rebuilt brain, political manipulator Jackie—eventually become reconciled to one another. And the immigration crisis is resolved, this time without bloodshed, in a spirit of peace and cooperation. Mars, and perhaps the human species, has come of age. Robinson's brilliant extrapolations and fascinating speculations are the product of hard and deep thought, in disciplines ranging from politics and economics through physics to microbiology. But with only a handful of well-realized characters, no plot, and hardly any incidents, what he's written is more textbook than novel: a disappointment for readers anticipating a more resounding conclusion. (Author tour)