Caesar's Comet and the Birth of the Roman Empire

In Natural History (Book II, 23, 93-94), the Roman writer Pliny explains: 'The only place in the whole world where a comet is the object of worship is a temple at Rome. His late Majesty Augustus had deemed this comet very propitious to himself, as it had appeared at the beginning of his rule, at some games which, not long after the decease of his father Caesar... he was celebrating... In fact he made public the joy that it gave him in these words: 'On the very days of my Games a comet was visible for seven days in the northern part of the sky. It was rising about an hour before sunset, and was a bright star, visible from all lands. The common people believed that this signified the soul of Caesar received among the spirits of the immortal gods...' This was his public utterance...' (tr. Rackham, 1938, 237). Coins struck by Augustus in 18 BCE show the comet of Divus Julius and the bust of his heir (Fig. 1, Seaby, 1952, Roman Silver Coins, Vol. 1, 97). The long gap between the purported 44 BCE sighting and the comet on coins of Augustus in 18 BCE has led to questions as to whether such an apparition ever took place (Gurval, 1997). Might the comet of 44 BCE have been Augustus' invention? Ramsey and Licht (1997) write: 'The answer to this question must be "surely not" for at least three cogent reasons.' One, traces of 'anti-Augustan' interpretations of the event. Two, comets were usually seen as threatening, but Octavian managed to turn this perception around. 'This stroke of genius on Augustus' part has to be regarded as one of the most remarkable examples of "spin" control in the whole of antiquity. Third and lastly, we can be certain that there was a comet in 44 BC because one is attested in our Chinese sources...' The July cometary outburst reached an apparent magnitude of -4, and the Sidus Iulium appeared repeatedly in Roman literature: Virgil (37 BCE), Ovid (8 CE), Pliny (77 CE), Suetonius (121 CE). Modern discussions of ancient texts and coins include works by Scott (1941) and by Pandey (2013) who shows coins that illustrate the evolution of Caesar's Comet. What would have qualified Julius Caesar for such a spectacular celestial ascent? Caesar had spent a fortune on bread and games in order to be elected Pontifex Maximus, highest priest of the Roman state religion. Any violence against the body of the Pontifex Maximus was taboo. As he amassed power under his own hand, Caesar must have felt invincible. After Caesar's demise, Augustus eventually appropriated the office of Pontifex Maximus (Res Gestae), along with the authority of consul and the veto power of tribune. Church and state became one. Caesar's comet had foretold the birth of the Roman Empire.