The secret life of the universe An astrobiologist's search for the origins and frontiers of life

Review by Booklist Review

Given that the universe is mind-bogglingly immense, the odds that Earth is the only location harboring life are infinitesimal. Astrobiologist Cabrol launches readers on a fascinating journey that considers the definition and origins of life along with the possible places in our solar system and beyond where extraterrestrial life forms might exist. More than 5,000 exoplanets (some Earth-like) have already been confirmed, and there are plenty more out there. Those planets can be categorized as terrestrial, super-Earths, Neptune-like, or gas giants. There are also rogue planets, "lonely worlds wandering in interstellar space." In our solar system, Cabrol appraises the potential for life on Mars, Jupiter's moons Europa and Ganymede, Saturn's moons Enceladus (featuring geysers) and Titan (where it rains methane), and the asteroid Ceres (which contains an abundant amount of ice). Yet she emphasizes exactly "how fragile habitability can be." As for conceivable kinds of alien organisms, they might range from simple (microbes) to intelligent (with highly advanced civilizations and technologies). Lots of intriguing items and concepts are introduced: biosignatures, the habitable zone of a star, cryovolcanism, magnetars, SETI projects, self-replicating von Neumann probes, the Fermi paradox, the panspermia hypothesis, and Dark Forest theory. An out-of-this-world discussion propelled by both curiosity and awe.

From Booklist, Copyright (c) American Library Association. Used with permission.

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Review by Publisher's Weekly Review

This stimulating survey from Cabrol, director of the Carl Sagan Center at the SETI Institute, details how she and other scientists search the cosmos for extraterrestrial life. Cabrol offers insight into what kinds of planets are most likely to harbor life by outlining theories for how life emerged on Earth, with some scientists claiming that the first organisms developed from alternating periods of dryness and wetness around volcanic hot springs, while others believe that reactions among RNA molecules in ice constitute a more likely genesis. Elsewhere, Cabrol notes that one study has detected phosphine, a compound "only produced by life on Earth," in Venus's atmosphere, and that geysers on Saturn's moon Enceladus suggest the planet has a mantle composed of water. Cabrol has a talent for making technical research accessible for general readers and serves up a bounty of fascinating trivia, pointing out that "rogue planets" wander the universe after getting "ejected from their parent systems" and that the exoplanet 55 Cancri e has a 2,700ºC surface "where gases behave almost like liquids." Amateur astronomers will be spellbound. Photos. (Aug.)

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Review by Kirkus Book Review

We are on the cusp of a new wave of exploration, according to a leading astrobiologist. Some people are in the enviable position of loving their work. Cabrol is one of them, and it shows in this wonderfully sweeping book. As director of the Carl Sagan Center at the SETI Institute, the author leads projects in planetary science and research, spending much of her time thinking about life beyond Earth. With the invention of advanced telescopes and exploratory spacecraft, "we are living in a golden age in astrobiology, the beginning of a fantastic odyssey." Cabrol is not a starry-eyed dreamer, and she readily admits that the first life we find outside of Earth is likely to be microbial. There are various theories about how life developed on Earth, and she examines them to establish where the chemical ingredients and environmental conditions for life might exist in our solar system. Planets long thought to be completely inhospitable are now being reconsidered, she notes. Mars, Venus, and the dwarf planets Pluto and Ceres are new possibilities. Cabrol is particularly excited by the moons Europa and Titan, which will be the subjects of unmanned explorations in the foreseeable future. Looking further afield, there are also intriguing prospects among the thousands of other planets discovered in the rest of the galaxy. In the concluding chapters of the book, Cabrol discusses the likelihood of encountering intelligent life and explains the Drake equation, used to estimate "the number of advanced extraterrestrial civilizations whose electromagnetic emissions are detectable." Along the way, the author also speculates about entirely new types of organisms. This is a book for anyone with an interest in scientific discovery and a perfect choice for any budding astronomer or astrobiologist. Combining enthusiasm and knowledge, Cabrol gives a lovely guided tour of the possibilities of the cosmos. Copyright (c) Kirkus Reviews, used with permission.

Copyright (c) Kirkus Reviews, used with permission.

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