Introduction

In March 1610 Galileo published a little book of sixty pages, The Starry Messenger, announcing the wonders he had seen through a telescope of his own making: the moon is not perfectly smooth, as Aristotle had taught, but covered with mountains, valleys and craters; the Milky Way is made of countless stars invisible to the naked eye; and four moons revolve around Jupiter. The book caused a sensation throughout Europe. In 1632 he wrote, in Italian, the Dialogue Concerning the Two Chief World Systems, in which Salviati, a Copernican, Sagredo, an intelligent neutral, and Simplicio, a stubborn Aristotelian, debate over four days. It was this book that brought him before the Inquisition. This volume contains the whole of The Starry Messenger and selections from the Dialogue.