Kepler's New Star (1604): Context and Controversy is a volume of ten essays, edited by Patrick J. Boner, focusing on the political and scientific discourse that enveloped German astronomer, philosopher, and devoted Lutheran Johannes Kepler and his study of the supernova of 1604. Known for his work in astronomy and his laws of planetary motion, Kepler is a key figure of the Scientific Revolution. This edited volume examines Kepler and one of his lesser-studied works, De Stella Nova. Published in 1606, De Stella Nova not only provides a detailed account of Kepler's observations of the supernova that appeared in October of 1604 in the constellation Ophiuchus; it also offers a recounting of the observations of his contemporaries.

The authors of this collection come from a wide variety of backgrounds, from astrophysics to Renaissance philosophy and early modern history of science. The essays can be loosely categorized around several themes. The first set of essays focuses on aspects of Kepler's arguments that challenged many of the theories presented by his contemporaries, which made up the fundamental cosmological beliefs of the time. Tessicini examines the role of Aristotelian concepts used by Kepler to support his argument against the endless extension of the universe, or “the infinite altitude.” Graney provides a full translation of chapter 16 of De Stella Nova, which includes Kepler's response to Tycho Brahe and other astronomers over the size of stars, while Luna analyzes Kepler's response to Bruno and William Gilbert over the scale and size of the cosmos—yet another way in which Kepler challenged the accepted cosmological beliefs of the period. As Boner notes, the work of these three scholars “sheds light on the early evolution of Copernican theory and how Kepler attempted to tailor it according to his own ontology.”

The next two essays focus on the interactions and exchanges that occurred between Kepler and other intellectual figures of the time. Boner examines the contentious dispute that emerged between Kepler and Johannes Krabbe, court astronomer in Wolfenbüttel, who considered the new luminary a comet, not a star, that was able to change in size and speed, a conclusion that Kepler strongly and publicly disagreed with. In similar fashion, Regier conducts a well-organized comparative analysis of Kepler and his court contemporary Anselmus Boëtius de Boodt, taking a broader approach and expanding his study to include subjects beyond the 1604 supernova where the two intellectuals were in agreement. The next two chapters provide a critical analysis of De Stella Nova itself. Kepler lived in a time when astrology and astronomy were not separate, and Rothman offers an analysis of Kepler's relationship with astrology through the lens of nature versus culture, focusing on Kepler's position as “both a practitioner and reformer” of astrology, of which he believed God was the ultimate architect. Similarly, Granada outlines the movement by Kepler's contemporaries to Christianize the constellations, concluding that Kepler's musings on reconfiguring the heavens likely influenced other German intellectuals.

The final three chapters extend the narrative of the book beyond Kepler's immediate scope and through the present day. Omodeo looks at the influence of Kepler on a number of intellectuals who followed him, including well-known figures like Rene Descartes and Pierre Gassendi. Cosci presents a survey of the epistemological exchanges that occurred in Italy following the appearance of the new star through the many scholars who wrote letters on the subject. In the final chapter, astrophysicist Blair offers a look at the impact on modern science that Kepler and the new star of 1604 had by offering an analysis of the star, now known as SN1604, through the lens of today's scientific practices.

Ultimately, this volume provides a broad analysis of the context in which Kepler developed his theories and calculations, as well as an examination of the role that Kepler's own ontological beliefs played in his theories of the heavens. While at times some chapters feel bogged down with minutiae, making it challenging for nonexperts of Renaissance science and philosophy to follow along and obfuscating the overall message, the final product is a well-rounded survey of Kepler's theories and contributions to science relating to the supernova of 1604.