Carl Sagan, Ann Druyan
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WHAT ARE THESE GRACEFUL VISITORS TO OUR SKIES? WE NOW KNOW THAT THEY BRING BOTH LIFE AND DEATH AND TEACH US ABOUT OUR ORIGINS.
Comet begins with a breathtaking journey through space astride a comet. Pulitzer Prize-winning astronomer Carl Sagan, author of Cosmos and Contact, and writer Ann Druyan explore the origin, nature, and future of comets, and the exotic myths and portents attached to them. The authors show how comets have spurred some of the great discoveries in the history of science and raise intriguing questions about these brilliant visitors from the interstellar dark.
Were the fates of the dinosaurs and the origins of humans tied to the wanderings of a comet? Are comets the building blocks from which worlds are formed?
Lavishly illustrated with photographs and specially commissioned full-color paintings, Comet is an enthralling adventure, indispensable for anyone who has ever gazed up at the heavens and wondered why.
"SIMPLY THE BEST."
The Times of London
"FASCINATING, EVOCATIVE, INSPIRING."
The Washington Post
"COMET HUMANIZES SCIENCE. A BEAUTIFUL, INTERESTING BOOK."
United Press International
"MASTERFUL . . . SCIENCE, POETRY, AND IMAGINATION."
The Atlanta Journal & Constitution
From the Trade Paperback edition.
Almost say veneration—with which the average astronomer regarded this beautiful and mysterious object stretching its wonderful stream of light across the sky. —E. E. BARNARD, THE PREEMINENT OBSERVATIONAL ASTRONOMER OF THE TIME, ON THE 1910 APPARITION OF COMET HALLEY Seventy-six years is a few generations or less, and so Halley’s Comet is a kind of metronome beating out the rhythm of human progress or decline. Its 1910 apparition was the first since the invention of the airplane and the last.
48-inch Schmidt telescope at Mount Palomar Observatory. Note the structureless faint dust tail and the extremely complex morphology of the ion tail. Comet Humason (1962 VIII). Note the ray structure. Mount Palomar Observatory photograph. Courtesy National Aeronautics and Space Administration. Astronomers spend long hours arranging photographs of the same cometary tail in their proper time sequence, and—with equipment ranging from a magnifying glass to a computer contrast enhancement.
Form is not very different from the pinwheel structures seen in many comets, and brought out in short exposure photography with a large telescope. Comet Bennett 1970 II is a recent example. For Comet Bennett, at least, the color of the pinwheel was yellow, implying that the structure is in the dust. You look at these forms and perhaps you will grant at least that if enough spinning, jetting comets pass by the Earth, sooner or later there will be one that presents something like a swastika to.
Around adolescent stars have been sighted recently. Accretion disks have also been found around infant stars formed only a million years ago. Thus, it now seems that the Kant-Laplace hypothesis is in its fundamentals verified, and by a technology that would have delighted both of them. The Sun, the planets, and their moons all condensed out of the same rotating and collapsing disk of gas and dust. This is why all the planets revolve in the same plane in which the Sun rotates. Newton’s view that.
Column are the ready markers of fearsome, planet-wide disasters. You have a planet where for tens of millions of years everything is fine. It’s enough to give even inveterate pessimists a sense of security. But then, maybe when you’d least expect it, tumultuous changes occur—changes so striking that they are instantly apparent to the eye and mind of observers like us, who have come into being hundreds of millions of years later. There is a steady background rate of extinction, of course. In our.