Caesar's Comet
Discovery | |
---|---|
Discovered by | Unknown |
Discovery date | May 18, 44 BC (earliest mention) |
Designations | |
Comet Caesar, Sidus lulium "Julian Star", Caesaris astrum "Star of Caesar", C/−43 K1, Great comet of 44 BC | |
Orbital characteristics | |
Perihelion | 0.22 AU[1] |
Eccentricity | 1.0 (assumed)[1] |
Inclination | 110° |
Last perihelion | May 25, 44 BC[1] |
Next perihelion | Ejection trajectory assumed |
Caesar's Comet
Based on two questionable reports—one from China (May 30) and another from Rome (July 23)—an infinite number of
As a result of the cometary outburst in late July, Caesar's Comet is one of only five comets known to have had a negative absolute magnitude (for a comet, this refers to the apparent magnitude if the comet had been observed at a distance of 1 AU from both the Earth and the Sun[8]) and may have been the brightest daylight comet in recorded history.[9][verification needed]
In the absence of accurate contemporary observations (or later observations confirming an orbit that predicts the earlier appearance), calculation of the comet's orbit is problematic and a
At that distance, the Sun provides less light than the full Moon provides to Earth.History
Caesar's Comet was known to ancient writers as the Sidus Iulium ("Julian Star") or Caesaris astrum ("Star of Julius Caesar"). The bright,
The Comet became a powerful symbol in the political
To make that soul a star that burns forever
Above the Forum and the gates of Rome.[14]
On Roman coinage
Tracing the coinage from 44 BC through the developing rule of Augustus reveals the changing relationship of Julius Caesar to the Sidus Iulium. Robert Gurval notes that the shifting status of Caesar's Comet in the coinage follows a definite pattern. Representations of the deified Julius Caesar as a star appeared relatively quickly, occurring within several years of his death. About twenty years passed, however, before the star completed its transformation into a comet.
One of the clearest and earliest correlations of Caesar to a comet occurred during the
In literature
The poet Virgil writes in his ninth eclogue that the star of Caesar has appeared to gladden the fields.[17] Virgil later writes of the period following Julius Caesar's assassination, "Never did fearsome comets so often blaze."[18] Gurval points out that this passage in no way links a comet to Caesar's divine status, but rather links comets to his death.[15]
It is Ovid, however, who makes the final assertion of the comet's role in Julius Caesar's deification. Ovid describes the deification of Caesar in Metamorphoses (8 AD):
Then Jupiter, the Father, spoke..."Take up Caesar's spirit from his murdered corpse, and change it into a star, so that the deified Julius may always look down from his high temple on our Capitol and forum." He had barely finished, when gentle Venus stood in the midst of the Senate, seen by no one, and took up the newly freed spirit of her Caesar from his body, and preventing it from vanishing into the air, carried it towards the glorious stars. As she carried it, she felt it glow and take fire, and loosed it from her breast: it climbed higher than the moon, and drawing behind it a fiery tail, shone as a star.[20]
It has been argued recently that the idea of Augustus's use of the comet for his political aims largely stems from this passage.[21]
In
Modern scholarship
In 1997, two scholars at the
Robert Gurval of
See also
References
- ^ a b c d e "JPL Small-Body Database Browser: C/−43 K1" (arc: 54 days). Jet Propulsion Laboratory. Retrieved 2015-11-16.
- ISBN 0788502735.
- , p. 94.
- ^ The Comet of 44 B.C. and Caesar's Funeral Games (John T. Ramsey, A. Lewis Licht) p. 125
- ^ Cometography Vol 1 p. 22 by Gary W. Kronk
- ^ See Ramsey pp. 122–23: (Comet absolute magnitude H1 of 3.3) + 2.5 * (n of 4) * log (Sun distance of 0.220 AU) + 5 * log (Earth distance of 1.09 AU) = perihelion apparent magnitude of −3.1.
- ^ The Comet of 44 B.C. and Caesar's Funeral Games (John T. Ramsey, A. Lewis Licht) p. 123
- Bibcode:1990acm..proc..327H.
- ^ Flare-up on July 23–25, 44 BC (Rome): −4.0 (Richter model) and −9.0 (41P/Tuttle-Giacobini-Kresák model); absolute magnitude on May 26, 44 BC (China): −3.3 (Richter) and −4.4 (41P/TGK); calculated in Ramsey and Licht, Op. cit., p. 236.
- ^ a b François Arago (1832). Tract On Comets. Translated by John Farrar. Hilliard, Gray. p. 71.
- ^ "Horizon Online Ephemeris System". California Institute of Technology, Jet Propulsion Laboratory. Retrieved 2015-11-16.
- ^ Suetonius, Divus Julius; 88 The Twelve Caesars
- Naturalis Historia, 2.93–94.
- ^ Ovid, Metamorphoses; XV, 840.
- ^ JSTOR 4238747.
- S2CID 162367121.
- ^ Williams, Mary Frances (2003). "The Sidus Iulium, the divinity of men, and the Golden Age in Virgil's Aeneid" (PDF). Leeds International Classical Studies. 2 (1). Archived from the original (PDF) on 2014-06-11. Retrieved 2014-03-23.
- ^ Georgic 1.487–488 qtd. In Ramsey and Licht, Op. cit
- ^ Siculus, Titus Calpurnius; Scott, Edward John Long (1890). "The Eclogues of Calpurnius".
- ^ Ovid, Metamorphoses; XV; 745–842 Archived 2015-02-23 at the Wayback Machine.
- S2CID 153697502. Retrieved 2014-03-22.
- ^ Ramsey and Licht, Op. cit.
- ^ The Comet of 44 B.C. and Caesar's Funeral Games (John T. Ramsey, A. Lewis Licht) pg 121
- ^ Marsden, Brian G., "Forward"; In: Ramsey and Licht, Op. cit.