The Ides (15th) of March 1997 marked the 2040th anniversary of the murder of Julius Caesar in 44 B.C. (-43), and on that anniversary there was published the first book-length study of the Great Daylight Comet that appeared in the year of Caesar's death and caused the Roman people to elevate Caesar to the status of a god. It was also in March of 1997 that in the northern hemisphere we enjoyed our best view of Comet Hale-Bopp, which tragically led 39 members of the Heaven's Gate cult to take their own lives, demonstrating how mysterious and awe-inspiring comets can be even in the modern age.

No. 39 in the American Classical Studies series of the American Philological Association
Scholars Press: Atlanta, Georgia
March 1997

The comet is shown above, on the cover of the book, at the two points of reported observation: on the left, with a tail, as seen from the Chinese capital in late May; on the right, as a star-like object, as seen from Rome in late July. These points are linked by our 0.224 A.U. orbit.

This unique collaboration between a classicist and physicist at the University of Illinois at Chicago is the first work to combine the evidence from both China and Rome for the spectacular daylight comet of 44 B.C. (-43), perhaps the most famous comet in antiquity. It is conclusively shown that the comet of 44 was seen from Rome in July, not September, a significant revision of the prevailing view among astronomers who generally assign the comet to September under the influence of a false conclusion of Sir Edmund Halley. A reconstruction of the comet's historical context reveals that Julius Caesar's adopted son, the future emperor Augustus, played a much greater role than hitherto suspected in causing this comet to be interpreted as a sign of Caesar's elevation to the ranks of the gods. Astronomical calculations based upon eye-witness accounts yield a range of orbital parameters; fifteen star-charts and graphs show how the comet appeared from Earth. This investigation, which also examines allusions to this comet in astrological literature from later antiquity, sheds new light on the significance of the comet as a powerful symbol in the political propaganda that launched Augustus' career.

e-mail to authors: comet@uic.edu