This book is so bad, it is almost not worth commenting on. However, I decided I should write something about it, if only to warn others away.

Earth is destroyed by a rogue asteroid, but a rich Texan manages to sequester genetic material on the moon, so that future seeding of the planet may one day be possible. This genetic library is maintained by computers and robots, who monitor conditions on Earth and plan for the future. However, from time to time, the computer needs more information, so a handful of children are cloned, raised by the robots and sent to Earth when they turn 21 to see what can be seen. This is necessarily a long term project, so the computer clones the children over and over, as needed.

The stupidest part of all this is that the computer continues to clone the same 5 children over and over again (3 males and 2 females), even after it becomes clear that these particular children are not all that well-suited for the job. The library has genetic information for thousands of humans, so why are these defective children continually cloned in spite of their problems? No satisfying explanation for that is given. Furthermore, the clones carry the "racial memory" of not only their source parents, but also of their former cloned selves. This makes no sense at all -- the clones are made from the original genetic material, not from the remains of the clones. Even if memory was hard-coded this way, there is no way current clones could have the memories of former clones (many of whom died on Earth without returning to the station on the moon). I may not be able to accurately evaluate this portion of the story, as I have serious personal and professional biases against the notion that personality and/or memory has any biological basis.

However, that is not the only stupid thing about this book. The story is written as a series of vignettes, following each generation of clones as they descend to the surface. The the clones record everything they see and send their observations to the moon. Sometimes the clones seed the earth with various things, but usually they just look around and get killed by something. The characters are thinly drawn, which is not surprising, since the structure doesn't really provide an opportunity to flesh them out. However, what little characterization occurs is offensive -- the children are little more than charactered racial stereotypes (the sultry Hispanic pilot, the "dedicated to science" Asian, the bull-headed but cowardly German, the milquetoast Englishman, the strong and muscular black man). It's insulting. The story's emphasis is on the geologic, chemical and biological changes going on on the planet, most of which are mind-numbingly boring and seriously under drawn. It's as if the author picked up a book on evolutionary biology, read the introduction to each chapter, extrapolated some creatures from that and stuck them into a travelogue. Bah. The end is as cliched as it is lame, boring, trivial, obtuse and irritating. This is just not a good book.

It's particularly disappointing given Williamson's status in the field. Not only is he one of the Old Guard (having published his first story in 1928), but he also coined the word terraforming in a 1942 short story. Williamson's personal history is fascinating -- he was born in 1908 in the Arizona Territory, moved to New Mexico via a wagon train in 1915, served in World War II, earned a PhD in English in the 1950s and taught at a small university in New Mexico for 20 years. All of this provided him with rich fodder for some amazing science fiction that he churned out over a span of decades. Unfortunately, *none* of his genius is demonstrated in this book. Clearly, I'm going to have to reread some of his "Legion of Space" stuff in order to get the bad taste out of my mouth.