This volume considers the role comets may have played in the origins and evolution of life. This is the only book dealing in depth with this subject. It is particularly relevant in light of recent investigations of Halley's comet, of new insights into organic synthesis in meteorites and comets, and of new results of numerical simulations of cometary orbits and impacts on Earth. The book is intended as a comprehensive review of current research.

Exploring the Solar System series.

Many of the earliest books, particularly those dating back to the 1900s and before, are now extremely scarce and increasingly expensive. We are republishing these classic works in affordable, high quality, modern editions, using the original text and artwork.

This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work. This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work. As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.

What are asteroids, comets, and meteors made of? What can scientists do if an asteroid is headed toward Earth? Learn how astronomers prepare for space objects hitting Earth, from tracking them to building asteroid-hunting telescopes. Budding astronomers will learn all about meteors, asteroids, and comets, including the history of asteroids hitting Earth and the differences between space rocks.