The silver denarius coined in Caesaragusta (Zaragoza) in time of Emperor Augustus was found by chance along with many other currencies belonging to a treasure, that it hid in the early first century A.D. and that could belong to a veteran legionnaire enriched in subsequent Civil Wars to the death of Julio Cesar, settling after his discharge in the Iberian Peninsula.
On the front we find the head of Augustus with the inscription CAESAR AVGVSTVS, and on the reverse a comet radiated and registration DIVVS IVLIVS (Divine Julius).
This comet, known as "Sidvs Ivlivm" or "Caesar's Comet" (C/-43 K1), was visible for seven days in July year 44 B.C. during the celebration of the "Ludi Victoriae Caesaris" funeral games in honor of Julius Caesar, murdered a few months earlier, a fact that was interpreted as the soul's Cesar ascent to heaven and his deification.
Caesar's comet may have been the brightest daylight comet in recorded history.