The remarkable astronomical discoveries made by Galileo with the new telescope in 1609-10 led to his famous disputes with philosophers and religious authorities, most of whom found their doctrines threatened by his evidence for Copernicus's heliocentric universe. In this book, Eileen Reeves brings an art historical perspective to this story as she explores the impact of Galileo's heavenly observations on painters of the early seventeenth century. Many seventeenth-century painters turned to astronomical pastimes and to the depiction of new discoveries in their work, yet some of these findings imposed controversial changes in their use of religious iconography. For example, Galileo's discovery of the moon's rough topography and the reasons behind its "secondary light" meant rethinking the imagery surrounding the Virgin Mary's Immaculate Conception, which had long been represented in paintings by the appearance of a smooth, incandescent moon. By examining a group of paintings by early modern artists all interested in Galileo's evidence for a Copernican system, Reeves not only traces the influence of science on painting in terms of optics and content, but also reveals the painters in a conflict between artistic depiction and dogmatic representation. Reeves offers a close analysis of seven works by Lodovico Cigoli, Peter Paul Rubens, Francisco Pacheco, and Diego Velázquez. She places these artists at the center of the astronomical debate, showing that both before and after the invention of the telescope, the proper evaluation of phenomena such as moon spots and the aurora borealis was commonly considered the province of the painter. Because these scientific hypotheses were complicated by their connection to Catholic doctrine, Reeves examines how the relationship between science and art, and their mutual production of knowledge and authority, must themselves be seen in a broader context of theological and political struggle.