The Living Cosmos: Our Search for Life in the Universe [Paperback]

I have read a number of books on the prospects for extraterrestrial life over the years, and this is one of the best. Here are four other good ones published in recent years:

Darling, David. Life Everywhere: The Maverick Science of Astrobiology (2001
Grinspoon, David. Lonely Planets: The Natural Philosophy of Alien Life (2003)
Michaud, Michael A.G. Contact with Alien Civilizations (2007)
Webb, Stephen. Where Is Everybody?: Fifty Solutions to the Fermi Paradox and the Problem of Extraterrestrial Life (2002)

(See my reviews at Amazon.)

Notwithstanding all this ink, astrobiology is still looking for the first object of its contemplation. But Prof. Impey is not deterred. In this outstanding work he attempts to lay the foundation for this seemingly nescient science by exploring all aspects of life on earth and comparing what he has found to environments in space. What is extraordinary about this book is the sheer breadth of knowledge that Impey displays. More than that though is the enthusiasm he brings to the subject and the readability of his prose.

The Living Cosmos is first a book about life on earth, how it might have begun and how it has evolved, and second on how that knowledge might apply to the larger cosmos. To understand this epic story and what it might imply about life in the universe as a whole it is necessary to have some understanding of many allied sciences including chemistry, geology, physics, ecology, genetics, and many others. In extrapolating what we know about life on earth to the heavens, knowledge of astronomy, cosmology, and mathematics is necessary. It is amazing that Impey is so well vested in all these subjects. Frankly I am dazzled and reminded again of how little I know.

Impey begins with an examination of the scientific approach and how it has led us to know what we know today. Then he examines life's origins, beginning with the birth in the stars of the elements necessary for life (life as we know it, of course!). He follows this with a chapter on "Extreme Life," recent knowledge of which has greatly expanded our ideas about where life might be found, such as under the ice on Europa or under the barren surface of Mars. Chapter 4 is about how the forces of the planet and impacts from outer space have shaped life on earth. Chapter 5 looks at the possibilities for life in our solar system, while Chapter 6 goes to the stars and beyond. Finally in Chapter 7 Impey recalls Fermi's flippant but penetrating question, "Where are they?"and explores the speculations and ideas about extraterrestrial life. He recounts Drake's famous equation in some serious depth and brings us up to date on the latest thinking.

The question arises: why study astrobiology when there is as yet nothing to study, and indeed when there may never be anything to study? This book is in a sense an answer to this question. By looking at life from the point of view of how it might exist elsewhere broadens our understanding of life. By considering how differing and perhaps bizarre environments might affect life--from the surface of a brown dwarf to an interstellar gas cloud to the atmosphere of Jupiter, to the surface of Venus, etc., we gain insight into what life is and what forms it might take. A very real bugaboo for astrobiology is the possibility that we may encounter extraterrestrial life and not recognize it. This book is in part a preparation for that day in the hope that extensive knowledge about how different life can be will help us see life even if it takes on very strange forms. Another problem is how to communicate with alien forms of life. As Impey points out, we haven't a clue how to communicate with an octopus, so how can we expect to talk to E.T.? Just the recognition that these are potential problems is a first step toward solving them.

Impey distinguishes himself not only by the breadth of his knowledge, but through the wit and wisdom of his prose. Here are three examples:

"One extremophile's toxic dump may be another's pleasure palace." (p. 220)

"About 20 percent of [NASA] missions fail completely. This worry leaves most NASA engineers with just enough hair for a bad comb job." (p. 257)

"The debate over the existence of ETs might never be settled by observations, but it certainly can't be settled without them." (pp. 294-295)

This is a handsomely produced book with 29 pages of endnotes, a glossary, a list for further reading sorted by chapter, a list of media resources including web sites, CDs and DVDs, and a useful index. There are many grayscale illustrations and charts throughout the book; however for these old eyes they are a bit on the small side.

I have one small pet peeve. I don't care for the nouveau practice of providing reading lists by chapters. I would prefer a return to the old fashioned bibliography in which all the sources are listed in one place alphabetically by author. As it is here, the reader has to go through each chapter listing looking for a particular author or book. Better yet, have two lists, one by chapter subject matter (as here) and the other a conventional bibliography.