Delineates the two very different traditions of astronomy in medieval Islam: legal scholars watched the crescent moon to keep the calendar, and used shadows to keep the hours and direction of prayer, while astronomers constructed elaborate theories and mathematical tables to approach ever more precision in times and directions. The articles are reproduced from their original publication in various journals, 1982-91.

This volume of 12 studies, mainly published during the past 15 years, begins with an overview of the Islamic astronomy covering not only sophisticated mathematical astronomy and instrumentation but also simple folk astronomy, and the ways in which astronomy was used in the service of religion. It continues with discussions of the importance of Islamic instruments and scientific manuscript illustrations. Three studies deal with the regional schools that developed in Islamic astronomy, in this case, Egypt and the Maghrib. Another focuses on a curious astrological table for calculating the length of life of any individual. The notion of the world centred on the sacred Kaaba in Mecca inspired both astronomers and proponents of folk astronomy to propose methods for finding the qibla, or sacred direction towards the Kaaba; their activities are surveyed here. The interaction between the mathematical and folk traditions in astronomy is then illustrated by an 11th-century text on the qibla in Transoxania. The last three studies deal with an account of the geodetic measurements sponsored by the Caliph al-Ma'mûn in the 9th century; a world-map in the tradition of the 11th-century polymath al-BÃ(R)rûnÃ(R), alas corrupted by careless copying; and a table of geographical coordinates from 15th-century Egypt.

It was the astronomers and mathematicians of the Islamic world who provided the theories and concepts that paved the way from the geocentric theories of Claudius Ptolemy in the second century AD to the heliocentric breakthroughs of Nicholas Copernicus and Johannes Kepler in the sixteenth and seventeenth centuries. Algebra, the Arabic numeral system, and trigonometry: all these and more originated in the Muslim East and undergirded an increasingly accurate and sophisticated understanding of the movements of the Sun, Moon, and planets. This nontechnical overview of the Islamic advances in the heavenly sciences allows the general reader to appreciate (for the first time) the absolutely crucial role that Muslim scientists played in the overall development of astronomy and astrology in the Eurasian world.

A History of Arabic Astronomy is a comprehensive survey of Arabic planetary theories from the eleventh century to the fifteenth century based on recent manuscript discoveries. George Saliba argues that the medieval period, often called a period of decline in Islamic intellectual history, was scientifically speaking, a very productive period in which astronomical theories of the highest order were produced. Based on the most recent manuscript discoveries, this book broadly surveys developments in Arabic planetary theories from the eleventh century to the fifteenth. Taken together, the primary texts and essays assembled in this book reverse traditional beliefs about the rise and fall of Arabic science, demonstrating how the traditional “age of decline” in Arabic science was indeed a “Golden Age” as far as astronomy was concerned. Some of the techniques and mathematical theorems developed during this period were identical to those which were employed by Copernicus in developing his own non-Ptolemaic astronomy. Significantly, this volume will shed much-needed light on the conditions under which such theories were developed in medieval Islam. It clearly demonstrates the distinction that was drawn between astronomical activities and astrological ones, and reveals, contrary to common perceptions about medieval Islam, the accommodation that was obviously reached between religion and astronomy, and the degree to which astronomical planetary theories were supported, and at times even financed, by the religious community itself. This in stark contrast to the systematic attacks leveled by the same religious community against astrology. To students of European intellectual history, the book reveals the technical relationship between the astronomy of the Arabs and that of Copernicus. Saliba’s definitive work will be of particular interest to historians of Arabic science as well as to historians of medieval and Renaissance European science.

The rise and fall of the Islamic scientific tradition, and the relationship of Islamic science to European science during the Renaissance. The Islamic scientific tradition has been described many times in accounts of Islamic civilization and general histories of science, with most authors tracing its beginnings to the appropriation of ideas from other ancient civilizations—the Greeks in particular. In this thought-provoking and original book, George Saliba argues that, contrary to the generally accepted view, the foundations of Islamic scientific thought were laid well before Greek sources were formally translated into Arabic in the ninth century. Drawing on an account by the tenth-century intellectual historian Ibn al-Naidm that is ignored by most modern scholars, Saliba suggests that early translations from mainly Persian and Greek sources outlining elementary scientific ideas for the use of government departments were the impetus for the development of the Islamic scientific tradition. He argues further that there was an organic relationship between the Islamic scientific thought that developed in the later centuries and the science that came into being in Europe during the Renaissance. Saliba outlines the conventional accounts of Islamic science, then discusses their shortcomings and proposes an alternate narrative. Using astronomy as a template for tracing the progress of science in Islamic civilization, Saliba demonstrates the originality of Islamic scientific thought. He details the innovations (including new mathematical tools) made by the Islamic astronomers from the thirteenth to sixteenth centuries, and offers evidence that Copernicus could have known of and drawn on their work. Rather than viewing the rise and fall of Islamic science from the often-narrated perspectives of politics and religion, Saliba focuses on the scientific production itself and the complex social, economic, and intellectual conditions that made it possible.

Many scientists have come to realize that science and religion can nurture each other. One example was the flowering of science in the first centuries of Islam. For Dr. Imad-ad-Dean Ahmad, a Muslim and an astronomer, studying the universe is an expression of faith. Scientists and non-scientists should appreciate the insights in this passionate and lucid book. Dr. Ahmad's book has been widely acclaimed for its insights into the Islamic approach to science and the spiritual foundations of Western scientists such as Galileo, Newton and Einstein. A Palestinian trained at Harvard, he offers a unique perspective of the role of religion in science.

This book contains an edition—with an extensive introduction, translation and commentary—of The Light of the World, a text on theoretical astronomy by Joseph Ibn Nahmias, composed in Judeo-Arabic around 1400 C.E. in the Iberian Peninsula. As the only text on theoretical astronomy written by a Jew in any variety of Arabic, this work is evidence for a continuing relationship between Jewish and Islamic thought in the late fourteenth and early fifteenth centuries. The text’s most lasting effect may have been exerted via its passage to Renaissance Italy, where it influenced scholars at the University of Padua in the early sixteenth century. With its crucial role in the development of European astronomy, as well as the physical sciences under Islam and in Jewish culture, The Light of the World is an important episode in Islamic intellectual history, Jewish civilization, and the history of astronomy.