Blue Mars continues the epic story of humanity colonising and terraforming the planet Mars, but in being the conclusion of the trilogy it has some inherent differences to the first two, Red Mars (1992) and Green Mars (1993). Perhaps the biggest difference is that Blue Mars features fewer singular events, rather, the focus is more evenly spread across political, scientific and geological themes as the planet has become much more dominated by water, along with a terraformed habitable climate. Blue Mars is much more of a travelogue than the first two books, taking the reader back to Earth, which is beset with environmental problems, and across most of the major areas of Mars, in particular the northern ocean, now teeming with life. On Mars the changed landscape is seen through the eyes of many of the remaining first hundred, but also some new characters, such as Zo, a young arrogant woman who embodies the hubris of new generations who are free of Earth's influence and high on the possibility of living for centuries due to further refinements to the longevity treatments invented on Mars by scientists from the first hundred. The clash between generations, between political movements and the demands of an ailing Earth drive the tensions that play out across the novel. As usual Robinson handles weighty themes and significant plot developments with aplomb. It's epic in scope, yet Robinson's detailed and highly descriptive prose style is as dense as ever, which all makes for an absorbing read.
I particularly enjoyed the sections in which the character Sax Russel features (in fact he is one of my all time favourite characters in science fiction). Sax is one of the first hundred and was behind the push to terraform Mars. His scientific perspective and philosophical musings regarding the clash between the terraforming of Mars and the 'Red Mars' movement's aim to preserve as much of Mars primal state as possible, are endlessly fascinating. Sax gives voice to Robinson's thoughts about science and philosophy, which, across all three novels, is a recurring theme. In Blue Mars this includes the notion as to whether geographical places have rights. Do rocks and geological formations have some kind of consciousness and do they have the right to remain 'unchanged', and what is 'unchanged' in any case? Sax slowly comes around to Ann Clayborne's views about keeping Mars as red as possible, although much of his terraforming work has born fruit. Also fascinating is the exploration of not just the physiological effects, but also the psychological effects of living for a very long time. As the remainder of the first hundred succumb to side effects of living so long, Sax makes up his mind to do something about it, and the resulting treatment and aftermath is one of the highlights of the novel, bringing together all of the remaining first hundred for a nostalgic send-off. Humanity is also branching out to other parts of the solar system and beyond, which is explored in a speculative, yet very convincing way by Robinson. The ending has a satisfying emotional impact and wraps up what really is one of the great trilogies in modern science fiction. Once again, perhaps stay away if you mostly enjoy space operas or soft science fiction, but for those who love hard science fiction, the Mars trilogy is highly recommended.
