Some science behind the scenes

Comet

First a definition from Wikipedia:

A comet is an icy, small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process called outgassing.

This produces a visible atmosphere or coma, and sometimes also a tail. These phenomena are due to the effects of solar radiation and the solar wind acting upon the nucleus of the comet.

Comet nuclei range from a few hundred metres to tens of kilometres across and are composed of loose collections of ice, dust, and small rocky particles.
The coma may be up to 15 times the Earth's diameter, while the tail may stretch one astronomical unit. If sufficiently bright, a comet may be seen from the Earth without the aid of a telescope and may subtend an arc of 30° (60 Moons) across the sky. Comets have been observed and recorded since ancient times by many cultures.

Comets can be both long lasting in the sky and bright.

133 BC, Amiterno, 70 Roman miles NE of Rome, Italy - Sun at night

The literature of the UFO field often quotes this event, with the mention that "Under the consulate of Africanus and Fabius, the sun was seen shining at midnight." In reality this object was probably a comet, as recorded by Lucius Annaeus Seneca and Marcus Junianus Justinus in their books. According to Seneca, during the reign of Attalus III, King of Pergamum, "a comet appeared, of moderate size at first. Then it rose up and spread out and went all the way to the equator, so that its vast extent equaled the region of the sky which is called the Milky Way" (Quaestiones Naturales).

Justinus noted that at the birth of Mithradates VI Eupator "a comet burned so brightly for 70 days that the entire sky seemed to be on fire. In its greatness it filled a quarter of the heavens, and with its brilliance it outshone the sun, while its rising and setting each took a period of four hours." (Historiae Philippicae). While there is no proof both writers were referring to the same event, the reign of Attalus III has been dated from 137 to 132 BC, while Mithradates VI Eupator was born between 133 and 131 BC. The descriptions do seem to coincide. Furthermore, a Chinese document, the Han shu, records that a spectacular comet was seen between August and September 134 BC lasting 30 days, while the twelfth century text, T'ungkien kangmu, notes the reign changed due to a comet seen in 133 BC.

At one time comets were classified in the same way that UFOs are.  But it is now possible via books such as Cometography: A Catalogue of Comets by Gary W. Kronk and Brian G. Marsden (Cambridge University Press ) to identify whether a UFO is a comet or not.

In the East, they were often known as 'dragons' and this quote may help to show why

Pliny - Natural History (Book II, Chapter XXII)

"There are stars that suddenly come to birth in the heaven itself; of these there are several kinds. The Greeks call them 'comets,' in our language 'long-haired stars,' because they have a blood-red shock of what looks like shaggy hair at their top. The Greeks also give the name of 'bearded stars' to those from whose lower part spreads a mane resembling a long beard. 'Javelin-stars' quiver like a dart; these are a very terrible portent."

Prophecy and agents of doom!

A number of apocryphal tales have circulated for many years about the destruction of famous places as a consequence of comets, some have been found to be simply hoaxes.............

336 BC, Venice, Italy - Alexander the Great, and the UFO that shook Venice

According to a letter he wrote to Aristotle, Alexander the Great seized Venice when an object came down from the sky, shot a beam, and crumbled the walls. This is an entirely spurious account: We traced the story and discovered it was about the use of gunpowder, not an unexplained flying object. The Aristotle letter is a known medieval forgery, only famous because Dante mentions it.

 

Left:  Woodcut of the Great Comet of 1577 which appeared in November.  Whether one counts this as a significant event or not depends on where you were born, but on December 13 – Francis Drake left Plymouth, England, aboard the Pelican, with four other ships and 164 men, on an expedition against the Spanish, which became a circumnavigation of the earth.

But right up to the sixteenth century, comets were usually considered bad omens of deaths of kings or noble men, or coming catastrophes, or even interpreted as attacks by heavenly beings against terrestrial inhabitants.  Pliny the Elder believed that comets were connected with political unrest and death.

Interestingly, however, there are examples where indeed they have been present at significant events.  Halley's Comet appeared in 1066, prior to the Battle of Hastings, and is depicted in the Bayeux Tapestry.

July 43 BC: The Comet of Murtine, Croatia

Pliny the Elder tells that Augustus wrote "On the very days of my games, a comet was visible over the course of seven days, in the northern region of the heavens. It rose at about the eleventh hour of the day and was bright and plainly seen from all lands. The common people believed that this star signified the soul of Caesar had been received among the spirits of the immortal gods. On this account, it was added as an adornment to the head of the statue of Caesar that I, not long afterwards, dedicated in the Forum."

And the following account of a probable comet also indicates that there were reasons why people believed that correlations occurred.  Trajan Decius was emperor from 249 to 251.

Circa 249-  Britain: Britton, C.E., A Meteorological Chronology to A.D. 1450, London: H.M.S.O., 1937

"At his [Decius'] coming to the Throne it Rained Blood in divers parts of this Kingdom, and a Terrible Bloody Sword was seen in the Air for three Nights, a little after Sunset."  

 

 

 

Observations

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