Excerpt from Comets: Their Origin, Nature and History To introduce our brief study of Comets a glance at the Solar System will be in place. The ancients believed that the earth was the center of the universe and that the sun, moon, and stars revolved around it once in twenty-four hours. It was Copernicus, a Polish astronomer, born nineteen years before Columbus discovered America, who first taught the world that the sun is fixed in the sky and that the planets, of which the earth is one, whirl around it in sublime revolutions through space. This is known as the Copernican System. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.