دانلود کتاب Eclipse: The Celestial Phenomenon That Changed the Course of History

Ancient peoples were clearly disconcerted by them. The Romans marked pivotal battles with the Greeks by references to an eclipse. The date of the crucifixion of Jesus Christ has been derived by using biblical mentions of an eclipse. Perhaps most famously, Christopher Columbus extorted much-needed foodstuffs from some increasingly unfriendly native hosts by purporting to demonstrate the wrath of his most powerful God when he accurately predicted a lunar eclipse.The pattern that eclipses follow-a cycle, called the saros-was actually calculated thousands of years ago. However, it is only with the help of modern computers that we have been able to analyze and appreciate the data. Eclipses provide unique opportunities for today's scientists to study such contrasting phenomena as the upper layers of the sun, the slowdown of our planet's spin rate, and the effects of celestial events on human psychology.In Eclipse, Duncan Steel expertly captures our continuing fascination with all manner of eclipses-including the familiar solar and lunar varieties and other kinds involving stars, planets, asteroids, and comets as well as distant galaxies and quasars. Steel helps us see that, in astronomical terms, eclipses are really rather straightforward affairs. Moving beyond the mysticism and the magic, the science of eclipses is revealed.