Alone in the Universe (eBook)

JOHN GRIBBIN is one of today's greatest writers of popular science and the author of bestselling books including In Search of the Multiverse (Wiley), In Search of Schrödinger's Cat, and Science: A History. He trained as an astrophysicist at Cambridge University and is now Visiting Fellow in Astronomy at the University of Sussex.

Acknowledgements xiPreface: The Only Intelligent Planet xiiiIntroduction: One in a Trillion 1Across the Milky Way; Hot jupiters; Planets in profusion; Dusty beginnings; Cosmic chemistry; The life of Gaia; Searching for other Gaias1. Two Paradoxes and an Equation 26The cosmic lottery and the Drake equation; The inspection paradox and the Copernican principle; Panspermia and the Fermi paradox; Probing for an answer2. What's So Special about Our Place in the Milky Way? 55Making galaxies; Making metals; Mixing metals in the Milky Way; Our place in the Milky Way; The Galactic Habitable Zone; Catastrophic comets3. What's So Special about the Sun? 80The narrow zone of life; The Sun is not an average star; Perturbing partners; Blasts from the past; The mystery of solar metallicity; Until the Sun dies; Postponing Doomsday4. What's So Special about the Solar System? 100Too hot to handle; The geography of the Solar System; Making planets; Making the Solar System; Making the Earth; The special one5. What's So Special about the Earth? 126Like a diamond in the sky; A planetary jigsaw puzzle; Creating continents; A fi eld of force; Venus and Mars; A planetary stabilizer; Plate tectonics and life6. What's So Special about the Cambrian Explosion? 151I. Contingency and ConvergenceThe Cambrian explosion; The Burgess Shale; Contingency; Convergence; The third way7. What's So Special about the Cambrian Explosion? 167II. Hothouse Venus/Snowball EarthAfter the deep freeze; Tipping the balance; From without or within?; The archetypal impact; Cosmic clouds and comet dust; Diamond dust and a facelift for a goddess8. What's So Special about Us? 184Chance, necessity and the decimal system; The molecular clock; The trigger for change; The pacemaker of human evolution; The fate of technological civilization; The fate of the Earth; No second chanceFurther Reading 206Index 211

"This book's title exaggerates the author's argument about the rarity of life in the "universe": Gribbin (astronomy, Univ. of Sussex, UK; In Search of the Multiverse) claims only that intelligent life in the Milky Way galaxy (not the entire universe) is almost certainly limited to Earth. Since there are billions of galaxies in the visible universe (and possibly an infinite number beyond the reach of our instruments), his carefully limited claim is sensible. He presents a formidable array of evidence from astronomy, astrophysics, geology, and evolutionary biology to support his basic assertion. Gribbin's definition of intelligent life on Earth includes only Homo sapiens, so he is weighing the likelihood that species on other planets within the local galaxy have intelligence equaling or exceeding that of humans. His case is well presented, but the odds may shift in the next few decades as more data are gathered on the Earthlike planets outside our solar system. VERDICT Gribbin is a veteran author of popular science books; this new volume should be of great interest for all readers curious about the possibility of life beyond our own planet. Strongly recommended."—Jack W. Weigel, formerly with Univ. of Michigan Lib., Ann Arbor (Library Journal, November 15, 2011)"The Milky Way contains a few hundred billion stars, but almost certainly contains only one intelligent civilization," says astrophysicist and veteran popular science writer Gribbin (The Theory of Everything). In an infinite universe, on the other hand, anything is possible, but we can only explore such questions closer to home. Gribbin makes a thoroughly lucid and convincing case. Recent astronomical observations have shown that exoplanets—worlds orbiting other stars—are more common than we expected, but Earth-like worlds are rare. And even planets in a "habitable zone" of both a galaxy and an individual star need water and the right organic compounds to engender and sustain carbon-based life. "Life got a grip on Earth with almost indecent haste," but it took Earth's metallic core and a near-twin Moon to stabilize Earth's tilt and steer off dangerous radiation; equally advantageous to Earth, Jupiter’s mass pulls in most of the comets and asteroids that might otherwise smash into us. Gribbin lays out the details one by one, building a concise case that "[w]e are alone, and we had better get used to the idea." (Dec.) (Publishers Weekly, October 24, 2011)