| THE LIVING COSMOS Our Search for Life in the Universe Chris Impey New York: Random House, December 2007 |
Rating: 5.0 High |
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| ISBN-13 978-1-4000-6506-6 | ||||
| ISBN-10 1-4000-6506-2 | 393pp. | HC/BWI | $27.95 | |
With our burgeoning collection of extrasolar planets growing by leaps and bounds, the subject of life on other planets has taken on new interest. As University Distinguished Professor at the University of Arizona and deputy head of one of the most renowned departments of astronomy in the nation, Chris Impey is well qualified to expound on this topic.
He begins his book by reprising the history of astronomy that brought us to this point: the dawn of astrobiology, the science of life elsewhere than on Earth. We have no solid evidence that there is any such life to study — and yet everyuthing we learn about the cosmos makes us more sure that there must be. That is still speculation, of course. But from time immemorial, the greatest thinkers of their day held that life, in forms most wondrous and varied, is certain to exist somewhere in all that vastness.
"It's quite peculiar to be human. Our lives are filled with events and episodes, with work and recreation, with the ebb and flow of friends and family. Seen from above, our actions would seem as purposeful as the activity of bees in a hive or squirrels in a forest. Yet we each house the awareness that we're living, conscious entities. We reflect on our exixtence. We know that we will die. Perhaps we share self-awareness with a few other species on Earth. But no other creature has gained knowledge of its place in the largest landscapes of time and space." – Page vii |
Dr. Impey next describes the evidence from physics, chemistry, geology, and biology that lend weight to our speculations. So-called extremophiles — life forms that thrive in extreme heat or cold, acid, alkaline or salt concentrations, or endure massive doses of radiation — are a big part of that. We now know that life survives miles deep within the crust of this planet, at undersea volcanic vents where the pressure keeps the water temperature well above the surface boiling point, and in lakes buried under the ice of Antarctica. We've also learned that some forms can endure long periods of hibernation. Just as with what once seemed to be Earth's privileged location, we are learning that our sort of life is not so special.
After taking us on a tour of the solar system, where we find several places that may harbor primitive life, Dr. Impey turns his gaze outward to other stars. He explains the methods of detecting planets orbiting those stars. (At the time the book was published, the tally was around 250.) Many stars like the Sun have planets; but so do double stars, white dwarf stars, even pulsars. As the search continues and methods improve, planets in longer orbits, and with smaller sizes, are beginning to show up. It won't be too long before we can identify those similar to Earth. He discusses the history of SETI (the one place where I wished for a little more detail) and the future of both kinds of searches. SETI, the search for extraterrestrial intelligence, proceeds fairly well without public funding, with new installations looking for both radio and laser signals. Meanwhile the quest for extrasolar planets looks forward to new NASA instruments, including a space-borne interferometer that can actually give us pictures of worlds like ours orbiting another nearby star.
The book is rich with information, well written, and supplemented by 133 illustrations. After the main text, a reader will find notes, a glossary, a reading list, media resources (Web sites and CD-ROMS/DVDs), illustration credits, and an index. The main defect of the book is that due to its comprehensiveness it necessarily covers some topics (like SETI) shallowly. Also, there are a number of careless statements. But all in all this is an impressive job, and I give it full marks.
To contact Chris Winter, send email to this address.