The discovery of a gradual acceleration in the moon’s mean motion by Edmond Halley in the last decade of the seventeenth century led to a revival of interest in reports of astronomical observations from antiquity. These observations provided the only means to study the moon’s ‘secular acceleration’, as this newly-discovered acceleration became known. This book contains the first detailed study of the use of ancient and medieval astronomical observations in order to investigate the moon’s secular acceleration from its discovery by Halley to the establishment of the magnitude of the acceleration by Richard Dunthorne, Tobias Mayer and Jérôme Lalande in the 1740s and 1750s. Making extensive use of previously unstudied manuscripts, this work shows how different astronomers used the same small body of preserved ancient observations in different ways in their work on the secular acceleration. In addition, this work looks at the wider context of the study of the moon’s secular acceleration, including its use in debates of biblical chronology, whether the heavens were made up of æther, and the use of astronomy in determining geographical longitude. It also discusses wider issues of the perceptions and knowledge of ancient and medieval astronomy in the early-modern period. This book will be of interest to historians of astronomy, astronomers and historians of the ancient world.

After several decades spent in astronomical semi-obscurity, the Moon has of late suddenly emerged as an object of considerable interest to students of astronomy as well as of other branches of natural science and technology; and the reasons for this are indeed of historical significance. For the Moon has now been destined to be the first celestial body outside the confines of our own planet to be reconnoitered at a close range by means of spacecraft built and sent out by human hand for this purpose. At the time of writing, not less than ten such spacecraft of American as well as Rus sian origin landed already on different parts of the lunar surface; and some of these provided remarkable records of its detail structure to a spatial resolution increased thousandfold over that attained so far from our ground-based facilities. A renewed interest in our satellite, stemming from this source, on the part of the students of many branches of science and technology has also underlined the need for presenting the gist of our present knowledge in this field in the form that could serve as an introduction to the study of the Moon not only for astronomers, but also for serious students from other branches of science or technology.

Visual Astronomy introduces the basics of observational astronomy, a fundamentally limitless opportunity to learn about the universe with your unaided eyes or with tools such as binoculars, telescopes, or cameras. The book explains the essentials of time a