It's fascinating to look into one of the earliest books of Kim Stanley Robinson, and the first of his novels to focus upon Mars. Kim Stanley Robinson is a writer whose books are defined as a rule by optimism: they can sometimes plunge themselves into pessimism, like in his The Years of Rice and Salt but at heart KSR fundamentally seems to believe in a better, brighter, future for humanity. But Icehenge is a more grey story, one of a future where Mars doesn't achieve the socialist future that KSR dreams of, but instead wastes away under a grey, all-consuming bureaucracy that has learned how to assimilate dissenters instead of simply crushing them. It suits the style of the book, one where after the dramatic initial clashes, people must learn to make their peace with an immortal society, the hopes and dreams of change being submerged beneath the tide of ennui.
While other books of Robinson deal with the development of prolong, enabling humans to live centuries, Icehenge is by far the most ambitious, stretching out the lifespans of humans to the better part of a millennia. It is a life where the endless tide of years annihilates memories and the past, producing individuals that are disconnected from the past, adrift, malleable. People who grow used to tolerating the world, without the youthly rebellion and spirit that leads to them seeing it in black and white, overthrowing it, a world without childishness, where time drags on and where closure is rarely sought. It's a long-running thread in the book, and one that presents a much more convincing and profound look at longevity than most other books.
KSR seems to me very much an intellectual, and his characters reflect this. The imperfection of the archeologist, Hjalmar Nederland, is refreshing from this angle: an intellectual certainly, but one who feels very real, very human. His grouchiness, isolationism, Scandinavian-style distance, the faux pas he commits when drunk, his single minded determination in following the thread of his research, the funks that he goes into when he loses any sense of purpose and meaning in the world: I quite enjoy him as a character. And so too, Edmon Doya, the youngest person, in a time where children had been stamped out, with a feeling of energy and drive that is absent elsewhere: KSR's characters are subtle, a certain feel that makes them appear real.
A mystery: the center of the book is Icehenge, the discovery of the monument on Pluto, the vast mysterious Stonehenge wrote in ice, towering on the frozen, alien world. It only takes up the last half of the book, and there are hints - very obvious ones - about who built it at the beginning of the book, but it is a chase to discover the makers that plays off hypotheses, that raises doubts, that finds and rejects ideas and dogs them with skepticism. Some aspects of it make less sense to me scientifically, such as the gravity on Pluto which isn't displayed nor talked about, despite it being barely a third of the Moon's gravity, already barely a sixth of the Earth's gravity, so it should have been a very different experience of travelling around Pluto, and stopping the outgoing ships at Pluto would be prohibitively expensive in fuel and time. But the idea of the monument itself is a gorgeous image, a wonderful gesture, and the search for it the glue that holds the book together. The entire book is a search for mysteries, from who destroyed New Houston, to Icehenge, to even the Mars Starship Association, and it makes for a tantalizing unravelling.
But the ending somehow lacks for the flare, the panache, the emotion which pervades so many of Robinson's other books: it ends with the discovery of the secret of Icehenge, speculation upon its origins, and... that's it. The centuries long mystery of finding out who constructed Icehenge, the story of discovering this fantastical, alien, bizarre monument, simply ends, a whimper rather than a bang, without any resolution, just a sense of sadness and a call for reflection.