Rome was the first mega-empire in the world. At its peak, it stretched from Western Europe to the Middle East, and over 50 million souls lived within its borders. Some historians believe the number could have been much higher, up to 100 million.
Rome began in the middle of the 8th century BC. It took centuries for this small town to grow into the Roman Empire, which peaked around AD 100. A familiar cliché reminds us of how long it took.
But it also took centuries before the Roman Empire broke up and dissolved.
During those centuries, what was left of the Empire shook, destroyed, and tried to rebuild itself. Leaders came and went as what was left of Rome was worn down by events and fragmented into small rump states.
One of these leaders was Empress Eirene Laskarina, and historians are not sure when she died. An exact date for the Empress's death would shed light on the following important events. Now a team of astronomers in Japan have used the historical record of comets combined with modern knowledge to record the date of their death.
The eastern Mediterranean has seen a frothy ferment of various empires over the centuries, and some of what we are today can be traced back to those early civilizations. The collapse of the Western Roman Empire in the 5th century AD led to some of these entities. One such civilization was the Byzantine Empire.
The empire under Justinian the Great in 555, at its greatest extent since the fall of the Western Roman Empire. Vassal statuses are shown in pink. Photo credit: By Tataryn – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=19926428
The Byzantine Empire was what was left of the Roman Empire in the eastern Mediterranean. It was also called Byzantium or the Eastern Roman Empire. The Byzantine Empire survived another thousand years after the Western Roman Empire fell in the 5th century.
Byzantium has been through much strife in its thousand years. In the early 1200s, Crusaders occupied Byzantium 'capital Constantinople and the empire was divided into three rump states. The Byzantine aristocracy fled and formed one of these backgrounds, the Empire of Nicaea. The Laskaris family founded it and the empire lasted a few decades from 1204 to 1261. The Nicaean Empire ended in 1261 when the Nicaeans, with the help of Empress Eirene, successfully restored the Byzantine Empire in Constantinople.
The Entry of the Crusaders to Constantinople, by Eugène Delacroix, 1840. Photo credits: By Eugène Delacroix – The Yorck Project (2002) 10,000 masterpieces of painting (DVD-ROM), distributed by DIRECTMEDIA Publishing GmbH. ISBN: 3936122202., Public Domain, https://commons.wikimedia.org/w/index.php?curid=150159
But before Empress Eirene's time, the eastern region was what we might call a hot mess.
After the Crusaders occupied Constantinople and divided Byzantium into three parts, Mongol invaders came to the region between 1242 and 1243. They weakened Nicaea and robbed the trunk of the territory. The Seljuk Turks were also actively aggressive towards Nicaea. From our point of view, the entire neighborhood looked like a chaotic kaleidoscope of leaders, peoples, and events as different empires and kingdoms fought against one another and territories were won and lost.
The Latin Empire, the Empire of Nicaea, the Empire of Trebizond and the Despotate of Epirus. The borders are very insecure. Photo credit: Von Jniemenmaa – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=57493
This is where Eirene Laskarina comes in. Eirene was heir to the Nicaean throne, and after the death of her first husband, her father married her in 1216 to a very successful soldier from a military family. His name was John III Batatzes.
Although Batatzes became the title leader of the Nicaean Empire and exercised power, Empress Eirene was actively involved in the government. Together, Batatzes and Eirene were able to develop mostly friendly relationships with their neighbors. Eirene is also given the honor of being a humble and circumspect empress, and in bringing about "a substantial improvement in the morale of her nation". According to historical reports, it was highly valued by the people.
Finally, in 1261, the Nicaean Empire restored the Byzantine Empire in Constantinople. This was a major event in the region, and although Empress Eirene had died about two decades earlier, she played a role in this eventual restoration. To understand the events of that time and Eirene's role in them, historians have worked to pinpoint the date of her death. Collectively, historians have determined that she died sometime between late 1239 and 1241.
This is where this new research comes in. The paper is entitled "Comet Records Revise the Chronology of the Eastern Mediterranean around AD 1240". The lead author is Koju Murata of the Institute for Advanced Research at Nagoya University. The paper is available on the prepress website arxiv.org.
Then as now, events in space provide some kind of historical calibration for events on Earth. In the case of Empress Eirene, her observations of comets near the time of her death can help pinpoint accurate dates. But historical observations are sometimes unclear. The ancients were not always strict in their observations and inferences, and they also knew much less about the cosmos.
Although Batatzes' restoration of the Byzantine Empire was a major event, the renewed empire suffered civil war and declining wealth until the Ottoman Turks captured the city in 1453. It remained in Ottoman hands until the early 20th century. Photo credit: By Jean Le Tavernier – Illustration by fr (Jean Le Tavernier) to a translation by Jean Miélot by Bertrandon de la Broquières Voyage d & # 39; Outre-Mer. It is one of three full-page miniatures in the Bibliothèque nationale de France, MSS fr. 9087, Folio 207 from the picture taken from: http: //expositions.bnf.fr/flamands/grand/fla_444.htm, Public Domain, https://commons.wikimedia.org/w/index.php?curid= 87115344
George Akropolites was a famous civil servant during the Byzantine period. He was also a historian and wrote a book called Chronographia or Annals. This book covered the period from the occupation of Constantinople by the Crusaders to the reconquest of Constantinople by the Nicaeans. In this book he connects the death of Empress Eirene with the appearance of a comet six months earlier.
The problem is that there are two cometary candidates in the historical record that could fit into the bill.
In their paper, the authors write that "George Akropolites, a famous official of the Empire, gives a report linking Eirene's death to a comet that appeared" six months earlier " appeared, indicating two comet candidates visible from the eastern Mediterranean in 1239 and 1240, one on June 3, 1239 and the other on January 31, 1240. "
They suggest that recent historians have favored the 1240 candidate who then pegs the death of Empress Eirene sometime around July 1240. But is that correct?
A Hubble image of Comet 2IBorisov from October 2019. The ancient accounts of comets and other events like eclipses help historians piece together timelines. Photo credit: From NASA, ESA and D. Jewitt (UCLA) – https://imgsrc.hubblesite.org/hvi/uploads/image_file/image_attachment/31897/STSCI-H-p1953a-f-1106×1106.png, Public Domain , https://commons.wikimedia.org/w/index.php?curid=83146132
The team from Japan took another look at it. They considered the historians' preference for the January 31, 1240 comet to be historical and not based on a rigorous assessment of the evidence. Could it be confirmed?
The date 1239 was actually a partial solar eclipse that Eirene himself witnessed. The date from May to June 1240 is the latest possible date on which Eirene's husband could have remarried. So her actual death was somewhere between the two.
Because of this, it is important to identify the comet that Akropolites is referring to. In their work they write: “It is therefore important to identify this comet in order to establish the chronology. With that in mind, this comet has been controversially identified with two different astronomical reports that Grumel (1958) cataloged as occurring on June 3, 1239 ((observed in) Europe) and January 31, 1240 ((generally observed)). . ”
The research team consulted various historical reports on comets from around the world. First they looked at the sighting of 1239.
A Japanese report says: “On the 23rd day in the 4th month (= May 27, 1239 in the Julian calendar) there is a beautiful sky. During the hour of the dog (= 7:00 p.m. to 9:00 p.m.), ghostly steam was observed in the northwest. "
Large comets were clearly visible in the sky, and their visits highlight our historical record. This is a woodcut of the Great Comet from 1577. Photo credit: By Ji? Rí Jakubuv There? Ický – Zurich Central Library, public domain, https://commons.wikimedia.org/w/index.php?curid=70591808
A written report from Cremona states: “On June 3rd (1239) a bearded star was observed along with a celestial object such as a torch hurrying westward. Shortly afterwards, they predicted a serious shortage of supplies and infinite things perished. "
The astronomers behind this research believe these reports describe something other than a comet, possibly a meteor. “Its rapid movement, its localized appearance and the plausibility of its short duration
are all properties that are more consistent with meteors or bolides. Meteors have long tracks, and when bright enough they are often compared to torches and beams. “They also indicate that some meteors can be brighter than the full moon.
The Japanese researchers next looked at the reports from 1240. "Various contemporary writers on the Eurasian continent have made records of the comet, which was first discovered in late January," they write. The authors also consulted a well-known Japanese chronicle called Azuma Kagami.
The theoretical light curves of C / 1240 B1 in 1240. The black or gray solid line
represents the theoretical light curve of C / 1240 B1 under the assumption of the absolute reference size of H = 2.5 and the Venus-adapted size of H = -0.8, which is based on the description of Azuma-Kagami. The apparent sizes of Jupiter (m ~ -2.1 to -2.0) and Venus (m ~ -4.5 to ~ -4.1, depending on the observation data) are also shown with an orange and red solid line, which is connected with the dashed line where Jupiter / Venus is not
visible at night. The yellow area represents the visible area with the naked eye (limit size of m = 4 ~ 4.5). Photo credit: Morata et al 2020.
This comet is called C / 1240 B1 and is considered one of the great comets. That just means it was exceptionally bright and easy to see with the naked eye. Its existence is confirmed in several reports from around the world.
The Japanese team concluded that the acropolitan's comet is C / 1240 B1, and that its appearance sets the date of death of the empress. According to them, Empress Eirene's death occurred in the summer of 1240, about six months after the comet appeared.
Knowing the date of Eirene's death confirms the deaths of other political figures, especially a leading couple from two neighboring kingdoms. It is also confirmed when her husband, Byzantine Emperor John III Batatzes, married his new wife. It is beyond the scope of this article to explain this in detail, but knowing the actual date of Eirene's death has a cascading effect on understanding the region's changing power dynamic and how Eirene's family eventually restored the Byzantine Empire in Constantinople.
After Eirene died, her husband remarried to cement his power alliances, which helped keep the Mongols at bay. Pope Gregory IX, too. Had excommunicated Batatzes, and Batatzes needed powerful alliances to curb the animosity the Pope felt towards him. It's also worth noting that people mourned when Empress Eirene died. But when her husband remarried so soon after her death, people's feelings turned against him.
Portrait of John III Doukas Batatzes, Emperor of Nicaea, 15th century. Photo credit: By an unknown Byzantine artist – Story by John Zonaras, Mutinensis gr.122, f.294r, Biblioteca Estense Universitaria, Modena (details)., Public Domain, https://commons.wikimedia.org/w/index.php curid = 10324390
Ultimately, all of these kingdoms and empires fell. As for the Roman Empire, some say that the Roman Catholic Church is the last rear of the empire long gone. So events from hundreds of years ago have repeated themselves over the centuries. The Pope is still venerated by over a billion people.
Events in space are one of our only tools to corroborate some ancient accounts and to piece together our broken accounts of human history. As the researchers write in their paper, "Astronomical phenomena recorded in various past periods around the world have sometimes been viewed as keys to determining the dates of important historical events that have been associated with these phenomena in historical writings." They also suggest that astronomical events can confirm the accuracy of the historical writings themselves.
Not much is known about the comet at the center of this story, C / 1240 B1. It has not resurfaced, and the spotty observations from 1240 are insufficient to allow astronomers to predict their next visit to the inner solar system. It could take thousands of years to return, or even millions. Or it may never return.
It's out there somewhere in space doing what comets do: mark the passage of time without paying any attention to human affairs.