This book is a compilation of essays by various astronomers, physicists, chemists, biologists, and science fiction authors. Originally published as First Contact, a number of the essays have been updated to take into account new discoveries and new essays have been added.
The authors include such SETI pioneers as Frank Drake and Phillip Morrison; current SETI practioners as Paul Horowitz, Kent Cullers, and Thomas van Horne (sometime sci.astro.seti participant); biologist Diana Riess; and science fiction authors Arthur C. Clarke and Isaac Asimov. By and large it is a notable group, though with some interesting omissions. For instance no essay by Carl Sagan or any of the recent planet hunters---Marcy, Butler, Mayor, or Queloz---appears. It would be interesting to know whether these omissions were deliberate, unintentional, or the result of some issue like copyright.
The authors' perspective on SETI ranges from agnostic to hopeful. In general, though, one should not look here to find long discussions of why the Earth is likely to be unique or nearly so.
Interesting essays include a sobering one by Diana Riess regarding attempts to assess the intelligence of dolphins. Even if the cosmos is teeming with technological civilizations, will we be able to communicate with them, given our limited communications with (and general treatment of) chimpanzees and cetaceans? In this sense, the clearly dated, but still enjoyable, story by Thomas Sullivan is an excellent inclusion in the book. Frank Drake's essay includes the provocative suggestion that large-brained dinosaurs were beginning to develop. Perhaps, as at least one other essay suggests, once animal life develops to a certain level of "complexity" on a planet, intelligence is almost inevitable?
Another notable feature of the book are the tables and figures, largely scattered throughout the book, but also in the Appendix. (In this regard a List of Figures and List of Tables in the forward matter would be helpful.) If you would like to know the temperature range of various spectral classes of stars (Tables 1 and 2 in Bova's essay) or a listing of the nearest stars (Appendix B), there is a table for these data in the book. If you'd like a graphical illustration of why radio searches have been the preferred means of SETI, Figure 2 in Klein's essay shows the various sources of "noise" at different wavelengths. I found particularly interesting Figure 2 in Appendix A showing the motion of Voyager 2 against the background stars over the next 5 years.
There are some deficiencies, however. The nature of the essay format means that there can be a fair amount of overlap between the various essays. One reads too many times that the Milky Way is a spiral galaxy and only one of billions in the Universe, that the Sun is a normal star and just one of billions in the Milky Way Galaxy, that astronomers have recently detected planets around other main-sequence stars. In places some additional editing seems necessary---there are occasional missing periods at the ends of sentences, uncapitalized words at the beginning of sentences, and the Drake equation makes an appearance in Brin's essay with a typo in it.
These deficiencies are relatively minor and certainly should not dissuade one from purchasing this book. I certainly regard this as a book at every SETI enthusiast should have in his or her library.
jlazio@patriot.net>