The Comet of 44 B.C. and Caesar's Funeral Games (1997) by J.T. Ramsey and A.L. Licht

This work is the product of a unique collaboration between a classicist and a physicist that began in 1993. It is our hope that the melding of these two fields will help to further our understanding of the spectacular, daylight comet that was observed in 44 B.C. (-43) during games that the future Roman emperor Augustus gave in honor of the late Julius Caesar. The comet of 44 possesses great historical significance because it came to be interpreted as a sign of Caesar’s apotheosis, and it has been celebrated and written about over the course of many centuries. The Chinese too observed a comet in 44 B.C., and it was quite probably identical with the one seen from Rome. We are fortunate to have this independent evidence of a comet sighting in 44, untainted by any suspicion that it could have been invented merely to lend greater historical significance to Caesar’s murder on the Ides (15th) of March. In Italy, the comet caught the fancy, it seems, of contemporary astrologers and prophets, and centuries later it intrigued the scientific minds of Sir Isaac Newton and Sir Edmund Halley.

To do justice to this multifaceted topic, our study must range well beyond the traditional bounds of classical scholarship, and keeping in mind the breadth of the audience for which this work is intended, we have tried to make it accessible to readers and scholars in many fields besides our own. We have translated into English all texts quoted in Greek or Latin; with the help of colleagues, we have consulted the relevant Chinese and Korean sources in the original and have provided fresh, accurate translations rather than relying upon older and often misleading English versions of those texts; and we have written précis to introduce sections of the discussion that have a technical, scientific nature. We present in one of the appendices what is intended to be the most comprehensive collection to date of Greco-Roman sources having to do with the comet of 44, its interpretation, and later fame. Those 36 texts are annotated and printed with facing English translations.

As the title of the book indicates, we discuss both the comet and the historical context in which it appeared: a Roman public festival that included in 44 B.C. funeral games for Julius Caesar. Under the empire, the public festival was celebrated annually on 20-30 July and was known as the ludi Victoriae Caesaris. Part one of our study challenges the prevailing modern view which holds that the ludi Victoriae Caesaris were celebrated for the first time in July 45 B.C., during Caesar’s lifetime. We review the two rival theories that have drawn this conclusion (put forward by Theodor Mommsen in the 19th century and by Stefan Weinstock in Divus Julius [1971]), and show that, on the contrary, 44 B.C. is most likely the first year in which games honoring Caesar were held in July. The only evidence pointing to a possible celebration of the ludi Victoriae Caesaris in July 45 is furnished by letter no. 44 in book 13 of Cicero’s Letters to Atticus (Epistulae ad Atticum 13.44). We argue that the interpretation of letter no. 44 should be radically revised, and show that it most likely alludes to the annual celebration of games to Apollo (6-13 July) and not to Victory games in honor of Caesar later in the month. This conclusion yields not only a new date for letter no. 44 but also revised dates for a whole series of Cicero’s letters in this jumbled part of the corpus since the dates of those other letters must be worked out by taking Att. 13.44 as the starting point in devising a chronology.

The new dating of the foundation of the festival to July 44 casts in an entirely new light the action of Caesar’s adopted son Octavian (the future emperor Augustus). According to our reconstruction, Octavian was breaking new ground by holding his games in July; he was not (as scholars have commonly supposed) simply perpetuating an already existing festival that had been established by Julius Caesar. Our reconstruction of the foundation of the festival in 44 B.C. also helps us to appreciate more fully why the Roman people so readily drew the conclusion that the sudden appearance of a comet during those games must have been a sign connected with the fate of Caesar. It turns out that not only did the comet shine forth in broad daylight, during games in Caesar’s honor, but the coincidence was made all the more striking for contemporary observers by the fact that the games in Caesar’s honor had never before been held in July, a factor that until now has never been given the weight it deserves.

Part two of our study shifts the focus to the comet and begins by calling attention to the fact that the bulk of what we are told about the July sighting rests ultimately upon the "official" version of the event as it was presented by the emperor Augustus in his Memoirs. It can be shown, however, that one or two sources preserve an anti-Augustan version of the comet’s significance and thus dispel any possible suspicion that the comet of 44 may have been a mere invention of Augustus’, designed to magnify the significance of Caesar’s assassination. (Indeed, since comets were invariably baleful omens, it is hard to imagine why Augustus would have borrowed trouble by inventing a comet if none had, in fact, existed.) As a further, independent witness to the existence of a comet in 44 B.C., we have the above mentioned reports of a sighting from China. We show that the astronomical records in the Chinese sources tend to be remarkably reliable and also that the comet which the Chinese report having seen in May-June is most likely an earlier sighting of the same comet that the Romans observed somewhat later in the year, towards the end of July. (The comet seen by the Chinese in the spring is usually treated in modern cometary catalogues as distinct from the one that appeared during Octavian’s games in July, but the sole basis for postulating two separate comets is a discredited theory of Sir Edmund Halley’s that the comet seen by the Romans had a period of 575 years and was identical with comets in A.D. 531, 1106 and 1680.)

We present a set of orbital parameters for the comet of 44 B.C. and calculate the range of uncertainties by taking into account certain features of the sightings in May-June from the Chinese capital and in July from Rome. Those sightings and the conclusions that may be drawn from them are illustrated in fifteen figures and two tables, which include four computer-generated star charts and two graphs showing the rising and setting times of the comet as seen from the Chinese capital and from Rome. We offer answers to these questions: (1) Why our western sources (including more than 20 extant letters of Cicero for the relevant period) fail to mention the comet in May-June; and (2) Why our Chinese sources fail to report the comet in late July, when it was seen from Rome in broad daylight. A significant factor affecting viewing conditions, especially in May-June, is the probable existence of a volcanic dust veil which occluded the sky over Italy after an eruption of Mt. Etna in the spring of 44. The timing of this eruption, in such close proximity to the assassination of Caesar, might well arouse suspicion since volcanic eruptions tend to be included in lists of portents that are invented to magnify great historical events. In this instance, however, it can be shown that like the comet, the fiery blast of a volcano (quite probably Etna) did indeed occur close to the Ides of March in 44. The report of Etna’s eruption that is found in our western literary sources (Livy and Virgil) is corroborated by meteorological data from China, by sulfate deposits in the glaciers of Greenland, and by tree ring evidence from North America, where dendrochronology points to a climatic change in the late 40’s B.C. that was most likely the result of a volcanic dust veil.

In the final chapter, we try to explain why the comet of 44 B.C. was treated so differently from other comets and interpreted as a positive omen. Normally comets were viewed as extremely baleful signs, and Caesar’s comet, the sidus Iulium ("Julian star"), is the only one that was ever commemorated on a Roman coin (first struck ca. 17 B.C., nearly three decades after the sighting). The explanation for the unique treatment of the comet of 44, we argue, lies in taking into account what appear to have been two rival, contemporary interpretations of the celestial phenomenon: (1) There were those who claimed that the bright light in the sky was not a comet at all but rather a "new star" (Octavian’s interpretation). (2) Others (among them, Octavian’s opponents) insisted, on the contrary, that the object was indeed a baleful comet signifying the coming of the "10th Age", which was to mark the end of the world. Some twenty years later, however, when Octavian (Augustus) came to write his Memoirs (ca. 24 B.C.) and no longer faced any serious challenge to his supremacy, he abandoned the view that the heavenly visitor was a new star, calling it instead a sidus crinitum (lit. a "hairy star", the Latin for "comet"). He did so, no doubt because by then a way had been found make the comet-interpretation contribute to the Augustan propaganda that a new Age was dawning under the benevolent guidance of Rome’s "first citizen" (Augustus). This new Age as defined by Augustus and his admirers was not, of course, the age of decline and decadence that had been foretold by Octavian’s opponents in 44, but it was presented, instead, as a restoration of a bygone Golden Age. This revision of the anti-Augustan interpretation of the comet’s message was apparently already taking shape when Virgil wrote his Fourth Eclogue towards the end of the decade in which the comet had appeared. In that poem Virgil predicts that the 10th Age will be a return to the Age of Gold when peace and prosperity prevailed. Traces of this reinterpretation of the comet of 44 as a positive, rather than a negative, omen may also be found in the astrological literature on comets that survives from late antiquity.

We conclude the final chapter by offering an entirely new way of interpreting what the Elder Pliny (Natural History 2.94) tells us was Augustus’ private view of the comet: Augustus is credited with interpreting the comet of 44 B.C. as a sign of his own "(re)birth". We show that the cryptic words attributed to Augustus are likely to have been inspired by the position of the stars when the comet rose, a position giving particular prominence to the zodiacal sign Capricorn, which Augustus (according to Suetonius, Life of Augustus 94.12, confirmed by numismatic evidence) regarded as the sign of his birth.