In this Companion Bowen and Rochberg have produced a very welcome and very useful volume. It will not – indeed cannot – be everything to everybody, but its coverage is impressive and well thought out, and the contents are remarkably well balanced overall.

The first note of pleasant surprise comes when one discovers the editors’ innovative use of the descriptor Hellenistic to include Greek, Babylonian, Egyptian and Roman material in the same volume and then to extend that coverage to include short chapters on Judaic, Mandean and early Christian reflections on astronomy and astrology. This is particularly pertinent to the history of astronomy, where the more common, more limited use of Hellenistic (Greek, post-Alexander, pre-Roman) would have confined their study to a decidedly small set of sources, many of them fragmentary. Of all the ancient intellectual pursuits there is probably no other whose multicultural origins and development are so clearly attested as astronomy's.

The second extended use of vocabulary in the title will be less surprising – but no less welcome – to scholars of premodern science. I refer to the broad reach of the term Astronomy to include astrology, astral divination, timekeeping, geography, medicine and even the theology of the heavens. We are thankfully past the time when one needed to explain at length why astrology or theology would be covered in a work on ancient astronomy, but it is still refreshing to see the latter topics treated as simply, unapologetically obvious aspects of the historical material and given healthy scope in the volume.

The temporal coverage is impressive, ranging from the fourth century bce to the rise of Islam. Here the editors are, I think unobjectionably, allowing their subject matter to dictate their periodisation. A political historian would not call a Sasanid kingdom Hellenistic, since significant lines of political, cultural and economic continuity had been broken between the Seleucids and the Sasanids, but in astronomy this was not the case. Perhaps we could cavil about whether Ptolemy, a man with the Latin praenomen Claudius who worked in second-century bce Alexandria, should be counted as Hellenistic rather than Roman, but I take Bowen and Rochberg's point that he represents a moment in the expansion of a continuous scientific tradition, one that saw a notable development in a period and a place roughly corresponding with the kingdoms spawned in the wake of Alexander. At any rate the adjective Hellenistic cleverly forces us to focus on the different intellectual cultures of those kingdoms, each of which made distinctive contributions to the astronomy on which Ptolemy built. Indeed, when I received this book for review, I was in the middle of writing a paper on the intellectual currents that came together in Alexandria and its environs to create the distinctive features of the classical horoscopic tradition, a set of currents that blend distinctively Babylonian, Greek and Egyptian ideas into a new hybrid form. It had never occurred to me to call Babylonian planetary theories Hellenistic – they are written in Cuneiform, after all –, but once the periodisation of the ‘classical’ form of Babylonian mathematical astronomy is noted, it is a product of the Seleucid era. Hellenistic thus becomes a perfectly good descriptor, and one that is particularly comfortable for the subject of the history of astronomy.

The fact that I was in the middle of a multicultural investigation of astrology when I received this volume also means that I was able to give it a good test run, as it were, to see how its coverage fared in a real-world scholarly application. Was its index or chapter layout useful and adequate for such a research project? I can happily say that it functions exactly like the excellent resource it was intended to be. There are quirks, to be sure, but these are to be expected in a collected volume of such broad scope and ambition. I suspect, for example, that the index entries were at least in part suggested by the authors of individual chapters, which means that there are minor inconsistencies. In one instance I had to take advantage of the searchability provided in the PDF of the volume (kindly sent to me by the press while I was waiting on the vagaries of international, Covid-era postage) rather than what turned out to be an incomplete index entry. In this case the two index entries listed for the topic were both from the same article even though the topic was raised or discussed by a number of other authors. Nevertheless, the layout is clear enough that for the most part users will have little trouble finding the articles and passages they need using the tools and indexes provided.

On this note, however, I raise the minor complaint that I wish the indexes had been compiled into one, rather than divided up into three, ‘Premodern Authors’, ‘Modern Authors’ and ‘General Index’. This format generated what I found to be temporary but unnecessary confusion and what appears to be some reduplication: one needs to look in two different indexes to make sure to find all the entries for Plato or Aratus, for example. Abū Ma‘ashar appears only in the General Index, while it took me until the third attempt to locate Tycho Brahe (he is under ‘Premodern Authors’, which might show that I am a little thick-headed, I suppose, but underscores the point that it would have been more user-friendly just to compile the three indexes into one).

Those minor worries aside, this is truly an excellent volume. It is about as complete as one could hope it would be, and it covers its very different topics (mathematics, philosophy, theology, technical astrology, cultural and intellectual history) consistently and often impressively well. The structure of the book is smart: the initial chapters lay the general technical groundwork (the celestial sphere, timekeeping, methods of measurement, mathematical tools) and outline the basics of the different theoretical approaches in the sources (Graeco-Roman, Babylonian, Egyptian). There follow six chapters on observational techniques and instruments, three on broader thematic questions, and then the bulk of the book takes up questions of the various historical contexts in which astronomy and astrology were used and debated. Here we find chapters on astrology, timekeeping, medicine, the popularisation and political exploitation of astronomy, priestly and scribal contexts, and finally theological and philosophical engagements with astronomy, cosmology and the foreknowledge of human destinies. The philosophical schools that receive full chapters of their own are limited to Stoicism and Plotinus, but one still feels that this is a representative start, even if it is not completely comprehensive (Aristotle and Plato are treated in other chapters at what seem to me to be reasonably adequate lengths).

The selection of modern authors represented is excellent, and the writing is consistently strong and in general admirably clear. In addition to the introductory material, Bowen contributes three chapters on theoretical matters (two on the use of hypotheses) and Rochberg an excellent chapter on the fertile relationship between Babylonian and Graeco-Roman astronomies as well as another on Babylonian horoscopes. Other contributors (in roughly the chronological order of their material) include: M. Ossendrijver, L. Brack-Bernsen, H. Hunger, C. Montelle, A. von Lieven, M. Ross, A. Spalinger, G. Graßhoff, N. Sidoli, G. Van Brummelen, R. Hannah, R.L. Kremer, J.C. Evans, T.E. Rihll, K. Geus, W. Hübner, D.W. Duke, D. Gieseler Greenbaum, S. Heilen, S. Mastorakou, A. Schmid, J.C. VanderKam, H.R. Jacobus, G. Cambiano, N. Denzey Lewis, C. Wildberg, J. Wilberding and S. Bhayro.

The volume is generously illustrated, frequently in colour, and there is an interesting ‘Historical Glossary’ of terms at the end. The bibliography lists the standard editions of ancient texts that are used in the volume. I note that such a list is not always included in scholarly works and is particularly welcome here, especially considering that few readers will be familiar with all the sources across the many ancient languages covered in the volume, which include: Akkadian, Aramaic, Coptic, Egyptian (Middle and Demotic), Ge‘ez, Greek, Hebrew, Latin, Mandaic and Syriac. Finally, there is a useful index of passages cited, divided by language.

This is an excellent and eminently useful volume, surveying and advancing the state of the field in a very welcome, cross-cultural and interdisciplinary format. Corners of this field seem to have been developing rather quickly in the last decade or two, and scholars will be grateful to the editors and authors for the timely appearance and impressive scope of this large book.