BMCR 2021.04.23

Hellenistic astronomy: the science in its contexts

, , Hellenistic astronomy: the science in its contexts. Brill's companions in classical studies. Leiden; Boston: Brill, 2020. Pp. xxxii, 751. ISBN 9789004400566 €197,00.

[Authors and titles are listed below.]

This is an absolutely wonderful book, well-written and a pleasure to read. It is generally based on the most recent research and very informative without being inaccessible to the layman. That the field of ancient astronomy is under rapid development is evident from the bibliography alone. Most of the cited works are from the last couple of decades and many new insights are here presented to a wider scholarly audience. It is generously supplied with interesting and relevant illustrations and its structure and composition take the reader by the hand so that it can be read easily from cover to cover. The individual chapters can also be read on their own, and the “Historical Glossary” and indices make it an excellent handbook as well. It provides a status quaestionis in a way which is at the same time accessible to the interested layman and contains a brilliant survey and much new to be learnt for the specialist in any parts of the vast topic covered as well. The title could lead one to expect a much narrower focus both on the subject and time period than is the case. Even though the title just refers to astronomy, the scope of the volume also covers the various forms of astrology current in the period under discussion. Astronomy and astrology were part and parcel in antiquity—and the two disciplines are sometimes in modern research referred to collectively as “astral sciences”—and the volume accordingly gives equal consideration to both. The period under discussion stretches from ca. 300 BCE to 750 CE, which is not covered by any existing label of historical periods but rather by terms such as Late Antiquity, Byzantine, Greco-Roman period, and so forth. The editors chose the term Hellenistic since this particular form of astronomy/astrology emerged in the cultural crucible of the Hellenistic Period (standard definition 323-31 BCE) and remained fundamentally unchanged until the advent of the world of Islamic scholarship in the 8th century CE. “Hellenistic Astronomy” is a meta-concept which refers to a certain set of principles, an overarching framework for understanding celestial phenomena, almost a mentality. “Hellenistic” is thus a conceptual label rather than a historical one.[1] The geographical and cultural sphere is large, spanning traditions from Babylonia, Egypt, Greece, and Rome, and Christian, Judean, Mandean, Stoic, and Hermetic perspectives.

The book is divided into three thematic parts forming a logical sequence. Part A, “Technical Requirements”, is devoted to the basic principles and descriptive tools used in Hellenistic Astronomy. It introduces the principles of geocentric astronomy and gives the reader the necessary background knowledge to understand the fundamentals of Hellenistic astronomical theories, hypotheses, and concepts. For instance, the chapter “Methods of Reckoning Time” by Robert Hannah explains in clear terms both concepts and some of the practical tools, such as the armillary spheres and the fascinating Antikythera Mechanism which was salvaged from an ancient shipwreck and has been reconstructed.[2] Part B, “Observations, Instruments, and Issues”, covers the observational foundations of Hellenistic Astronomy and the instruments used by ancient astronomers. It also deals with some thematic issues concerning the aims of Egyptian, Babylonian, and Greco-Roman astronomy. Part C, “Contexts”, makes up half the tome and is devoted to contexts in the widest sense—the cultural, religious, and philosophical settings, the practitioners, astrology, and horoscopes. In chapter 9.1 “The Sundial and the Calendar”, Robert Hannah quotes a comic playwright (perhaps Plautus) ranting against the tyranny of sundials which determines when it is time to eat so that people shrivel up in hunger rather than eat before the appointed time. In antiquity just as today, technological changes have never met with universal appreciation.

The attempt to paint an interconnected picture of Hellenistic Astronomy across the chosen time and cultures is quite successful. However, the reader should be aware that the cross-referencing is sometimes lacking, and there are some inconsistencies between chapters.[3] As an Assyriologist, I am especially pleased with the many references to Babylonian astral sciences and culture. The wonderful Babylonian sources are unfortunately still mostly known only to a small group of experts, and this volume will play an important part in putting them on the map. As far as we know, Babylonian astronomy did not evolve further after about 330 BCE, coinciding with the very beginning of the Hellenistic Period, but it continued to be practiced, and the texts were copied by scholars from Babylon, Uruk, and Nippur up into the 1stmillennium CE. These scientific circles clearly were important contributors to the development of Hellenistic Astronomy.[4] This is made evident both by the chapters devoted to Babylonian astral sciences and by the frequent references in chapters dealing with other aspects of Hellenistic astronomy and their historical links to Babylonian observation, tradition, and innovation.

Sometimes the unfamiliarity with the Mesopotamian material shines through, and the editors could have straightened some misconceptions out. For instance, the formulation on p. 241 that various events and phenomena, including the study of the exta of sacrificial animals, “formed complex signs from which one could predict important events that were relevant to kings, the state, and sometimes the individual”.[5] This is an oversimplification and somewhat of a misrepresentation of Babylonian divination. According to Diodorus of Sicily, whose descriptions of the world of Babylonian scholarship are wondrously precise and in accordance with what we know today from the archeological and textual record, the branch of divination in which the Babylonians were known to be particularly proficient was extispicy.[6] Extispicy and other forms of induced/artificial divination were primarily performed for individuals.[7] Indeed, astrology as practiced in the tradition of the omen-series Enūma Anu Enlil is special among Mesopotamian divination practices as it served only the king and the nation and dealt with events like famine, flood, rebellion, and war, which necessitated ritual action by the ruler to prevent.

In general, if anything could be desired from this generous book, it is the context of magical and divinatory practices more broadly. Another example is the discussion in chapter 9.3 “Hellenistic Astronomy in Medicine,” by Dorian Gieseler Greenbaum, of the Babylonian experts involved in medicine, the āšipu, the asû, and the bārû. The position of JoAnn Scurlock is cited uncritically without regard for the wide discussion on the subject that points to different understandings of their functions. These experts relied on magical remedies, and the diagnosis made by the āšipu and the etiology of illness was entirely religious rather than empirical. Further, the bārû (“seer”) could be consulted about recovery, but he would not “use every means available for curing disease” (p. 353); that was entirely out of his remit. On p. 354, the case of a star being appealed to by a sufferer to “judge his case” is mentioned as uncommon. In fact, the trope of the gods, also in their celestial aspect, as divine judges deciding cases put before them by suffering mankind is an absolute staple in Babylonian religion and magic, including divination. But these are minor issues. The Babylonian medical-magical corpora are huge and difficult to access, so any attempt to include them in a discussion of Hellenistic astronomy is praiseworthy. This is a book which deserves a wide readership.

Authors and titles

Preface Acknowledgments List of Illustrations and Tables List of Abbreviations
Prolegomena to the Study of Hellenistic Astronomy   Alan C. Bowen and Francesca Rochberg

Part A Technical Requirements:
1. The Celestial Sphere   Clemency Montelle
2. Methods of Reckoning Time   Robert Hannah
3. Quantitative Tools
3.1 Techniques of Measurement and Computation   Mathieu Ossendrijver
3.2 Planar and Spherical Trigonometry   Glen Van Brummelen
4. Theory of the Sun, Moon, and Planets
4.1 Fundamentals of Planetary Theory   Nathan Sidoli
4.2 Hypothesis in Greco-Roman Astronomy   Alan C. Bowen
4.3 Some Early Hypotheses in Greco-Roman Astronomy   Alan C. Bowen
4.4 The Ptolemaic Planetary Hypotheses   James C. Evans
4.5 The Hellenistic Theory of Eclipses   Clemency Montelle
4.6 Hellenistic Babylonian Planetary Theory   Mathieu Ossendrijver
4.7 The Babylonian Contribution to Greco-Roman Astronomy   Francesca Rochberg
4.8 Hellenistic Egyptian Planetary Theory   Micah T. Ross

Part B Observations, Instruments, and Issues:
5. Observational Foundations
5.1 The Observational Foundations of Babylonian Astronomy   Lis Brack-Bernsen
5.2 Experience and Observation in Hellenistic Astronomy   Richard L. Kremer
6. Astronomical Instruments
6.1 Hellenistic Surveying Instruments   Tracey E. Rihll
6.2 Hellenistic Maps and Lists of Places   Klaus Geus
6.3 Star-Lists from the Babylonians to Ptolemy   Gerd Graßhoff
6.4 Ptolemy’s Instruments   Dennis W. Duke
7. Thematic Questions
7.1 Issues in Hellenistic Egyptian Astronomical Writings   Anthony Spalinger
7.2 The Texts and Aims of Babylonian Astronomy   Hermann Hunger
7.3 Issues in Greco-Roman Astronomy of the Hellenistic Period   Alan C. Bowen

Part C Contexts
8. The Professional ἀϲτρολόγοϲ   Wolfgang Hübner
9. Hellenistic Astronomy in Public Service
9.1 The Sundial and the Calendar   Robert Hannah
9.2 The Antikythera Mechanism   James C. Evans
9.3 Hellenistic Astronomy in Medicine   Dorian Gieseler Greenbaum
10. Hellenistic Astronomy in Literature
10.1 Aratus and the Popularization of Hellenistic Astronomy   Stamatina Mastorakou
10.2 The Authority of the Roman Heavens   Alfred Schmid
11. Hellenistic Astronomy in the Training and Work of Priests
11.1 Hellenistic Astronomy and the Egyptian Priest   Alexandra von Lieven
11.2 Hellenistic Astronomy and the Babylonian Scribal Families   Mathieu Ossendrijver
12. Astral Divination and Natal Astrology
12.1 The Hellenistic Horoscope   Dorian Gieseler Greenbaum
12.2 Hellenistic Babylonian Astral Divination and Nativities   Francesca Rochberg
12.3 Hellenistic Horoscopes in Greek and Latin: Contexts and Uses   Stephan Heilen
12.4 Demotic Horoscopes   Micah T. Ross
13. Theological Contexts
13.1 Hellenistic Astronomy in Early Judaic Writings   James C. VanderKam
13.2 Astral Divination in the Dead Sea Scrolls   Helen R. Jacobus
13.3 Hellenistic Astronomy in Early Christianities   Nicola Denzey Lewis
13.4 Cosmology in Mandaean Texts   Siam Bhayro
13.5 Astral Discourse in the Philosophical Hermetica (Corpus Hermeticum)   Christian Wildberg
14. Hellenistic Astronomy in the Philosophical Schools
14.1 Astronomy and Divination in Stoic Philosophy   Giuseppe Cambiano
14.2 Plotinus on the Motion of the Stars   James Wilberding
Historical Glossary of Important Terms in Hellenistic Astronomy
Index of Passages
Index of Names
Index of Subjects


[1] However, not all the authors adhere to this terminology and other labels abound throughout the volume. This kind of astral science could also be called “papyrus-astrology” or “-astronomy” after the medium on which a large part of it was first written.

[2] See chapter 2, for the instruments, see also Chapter 6.4 “Ptolemy’s Instruments” by Dennis W. Duke and chapter 9.2 “The Antikythera Mechanism” by James C Evans.

[3]E.g., Chapter 8, “The Professional Ἀστρολόγος,” by Wolfgang Hübner (p. 314-315) describes the instruments used by astrologers without cross-reference to the chapters where they are depicted and described in the volume.

[4] Chapter 11.2 “Hellenistic Astronomy and the Babylonian Scribal Families” by Mathieu Ossendrijver.

[5] Chapter 6.3 ”Star-Lists from the Babylonians to Ptolemy” by Gerd Grasshoff.

[6] The passage mentioning that “they also show marked ability in making divinations from the observation of the entrails of animals, deeming that in this branch they are eminently successful” is cited on p. 437 in chapter 11.2 ”Hellenistic Astronomy and the Babylonian Scribal Families” by Mathieu Ossendrijver.

[7] Induced/artificial/provoked divination includes all methods where the supernatural is asked a question before an experiment is conducted and interpreted as their answer. In contrast, the supernatural sends signs unasked for in deductive divination.