Island of Ireland damaged by Comet in 6th Century

Manach wrote: »

This is incorrect.
Firstly, any impact debris would be present in the sub-soil, such as tektites etc.
Secondly, I've never come across any documentary evidence that mention this for this period.
Thirdy, the assumption that this was a cover-up by the Church belongs in the pages of the DaVinci code.

Upon examining the tree-ring record, Baillie noticed indications of severe environmental downturns around 2354 BC, 1628 BC, 1159 BC, 208 BC, and AD 540. The evidence suggests that these environmental downturns were wide-ranging catastrophic events; the AD 540 event in particular is attested in tree-ring chronologies from Siberia through Europe and North and South America. This event coincides with the second largest ammonium signal in the Greenland ice in the last two millennia, the largest being in AD 1014, and both these epochs were accompanied by cometary apparitions. Baillie explains the general absence of mainstream historical references to this event by the fact it was described in terms of biblical metaphors since at that time "Christian beliefs included the dogma that nothing that happens in the heavens could have any conceivable effect on the Earth."
Since then, he has devoted much of his attention to uncovering the causes of these global environmental downturns. He believes that impacts from cometary debris may account for most of the downturns, especially the AD 540 event. This hypothesis is supported in work by British cometary astrophysicists, who find that earth was at increased risk of bombardment by cometary debris in the AD 400-600 timeframe, based on the frequency of fireball activity in the Taurid meteor streams recorded in Chinese archives.
To provide further support to his cometary debris theory, Dr Baillie has searched the written record and traditions embodied in myths. There he has found evidence that the dates of the environmental downturns listed above are often associated with collapses of civilizations or turning points in history. The AD 540 event, for example, may have been associated with a catastrophe that ushered in the Dark Ages of Europe.
His book, Exodus to Arthur: Catastrophic Encounters with Comets (Batsford, 1999), relates the findings of his tree-ring studies to a series of global environmental traumas over the past 4400 years that may mark events such as the biblical Exodus, the disasters which befell Egypt, collapses of Chinese dynasties, and the onset of the European Dark Ages. The Celtic Gods: Comets in Irish Mythology (Tempus, 2005), co-authored with Patrick McCafferty, focuses on the AD 540 event as recorded in the historical records and myths of Ireland and shows that the imagery in the myths and the times between events are consistent with a comet with an earth-crossing orbit similar to P/Encke, as described by the British astronomers Victor Clube and Bill Napier. His latest book, New Light on the Black Death: The Cosmic Connection (Tempus, 2006), shows how the tree-ring and Greenland ice core evidence and descriptions in annals, myths and metaphors adduced in support of the global environmental downturn at AD 540, which included the Justinian plague, also applies to conditions extant at the time of the Black Death in AD 1348.

Mike Baillie is Professor of Palaeoecology at Queens University, Belfast, Northern Ireland. He is an authority on tree rings and their use in dating ancient events (every year, a tree adds a "ring" to its trunk as it grows - good years are represented by thick rings while bad years are represented by thin rings). He conducted a complete (and continuous) review of annual global tree growth patterns over the last 5,000 years and found that there were five major environmental shocks that were witnessed worldwide. These shocks were reflected in the ring widths being very thin. Wanting to know more, he turned to human historical records, and found that the years in question (between 2354 and 2345 BC, 1628 and 1623 BC, 1159 and 1141 BC, 208 and 204 BC, and AD 536 and 545) all corresponded with "dark ages" in civilisation.
The minimal growth of trees around 2350 BC has been associated in the past with the eruption of a volcano in Iceland. Yet, the period in question is also associated with floods, the creation of new lakes, and even the start of Chinese history. Furthermore, Marie-Agnes Courty, an archaeologist from France, has claimed new data regarding a catastrophe said to have occurred in the Middle East. Samples from three separate regions all appear to contain a calcite material found only in meteorites, and analysis of debris show what seems to be a combination of "a burnt surface horizon and air blast."
Indeed, some 40 cities throughout North Africa, the Middle East, Europe, and Asia are thought to have been devastated, or even disappeared, about the same time in a series of catastrophes.
The twelfth century BC is associated with the "Greek Dark Ages", the end of the Hittite civilisation in the Near East, the end of Bronze Age Israel, and the end of the Bronze Age Shang dynasty in China. Ancient Chinese history has the notion of "mandate from heaven", where the rulers were essentially subject to the whims of the sky above. Strange sights in the sky would not be seen as good news for Chinese Emperors. Indeed, around this time, Chinese records speak of : "...many gods and spirits were annihilated in this battle, and several stellar dignitaries were replaced by newcomers to the celestial domains." What could cause such global shocks? A likely answer, which has a good fit to the evidence, was what the European and Chinese observers described at the time as "dragons in the sky" - comets! We're not talking about an intact large comet (if that had hit in the last several millennia, we would not be here today), but rather fragments from a disintegrating comet or asteroid (small pieces like that which hit Tunguska in 1908). These would throw up dust that would envelope the world and dim our view of the Sun and skies. All this sounds like an interesting theory, but is there any evidence "above us" that fits in with the scenario. How do we account for so many impacts over the last several millennia when the consensus today in astronomy is that impacts causing global consequences (mild as well as major) are very rare?

Comet Collision Possible Cause of 'Dark Ages'

Scientists at Cardiff University, UK, believe they have discovered the cause of crop failures and summer frosts some 1,500 years ago – a comet colliding with Earth.
The team has been studying evidence from tree rings, which suggests that the Earth underwent a series of very cold summers around 536-540 AD, indicating an effect rather like a nuclear winter.
The scientists in the School of Physics and Astronomy believe this was caused by a comet hitting the earth and exploding in the upper atmosphere. The debris from this giant explosion was such that it enveloped the earth in soot and ash, blocking out the sunlight and causing the very cold weather.
This effect is known as a plume and is similar to that which was seen when comet Shoemaker-Levy-9 hit Jupiter in 1995.
Historical references from this period - known as the Dark Ages – are sparse, but what records there are, tell of crop failures and summer frosts.
The work was carried out by two Cardiff undergraduate students, Emma Rigby and Mel Symonds, as part of their student project work under the supervision of Dr Derek Ward-Thompson.
Their findings are reported in the February issue of Astronomy and Geophysics, the in-house magazine of the Royal Astronomical Society.
The surprising result of the new work is just how small a comet is needed to cause such dramatic effects. The scientists calculate that a comet not much more than half a kilometre across could cause a global nuclear winter effect. This is significantly smaller than was previously thought.
Dr. Ward-Thompson said: "One of the exciting aspects of this work is that we have re-classified the size of comet that represents a global threat. This work shows that even a comet of only half a kilometre in size could have global consequences. Previously nothing less than a kilometre across was counted as a global threat. If such an event happened again today, then once again a large fraction of the earth's population could face starvation." The comet impact caused crop failures and wide-spread starvation among the sixth century population. The timing coincides with the Justinian Plague, widely believed to be the first appearance of the Black Death in Europe. It is possible that the plague was so rampant and took hold so quickly because the population was already weakened by starvation.

Double impact may have caused tsunami, global cooling

Pieces of a giant asteroid or comet that broke apart over Earth may have crashed off Australia about 1,500 years ago, says a scientist who has found evidence of the possible impact craters.

Satellite measurements of the Gulf of Carpentaria revealed tiny changes in sea level that are signs of impact craters on the seabed below, according to new research by marine geophysicist Dallas Abbott.

Based on the satellite data, one crater should be about 11 miles (18 kilometers) wide, while the other should be 7.4 miles (12 kilometers) wide.

For years Abbott, of Columbia University's Lamont-Doherty Earth Observatory, has argued that V-shaped sand dunes along the gulf coast are evidence of a tsunami triggered by an impact.

"These dunes are like arrows that point toward their source," Abbott said. In this case, the dunes converge on a single point in the gulf - the same spot where Abbott found the two sea-surface depressions.

The new work is the latest among several clues linking a major impact event to an episode of global cooling that affected crop harvests from A.D. 536 to 545, Abbott contends.

According to the theory, material thrown high into the atmosphere by the Carpentaria strike probably triggered the cooling, which has been pinpointed in tree-ring data from Asia and Europe.

What's more, around the same time the Roman Empire was falling apart in Europe, Aborigines in Australia may have witnessed and recorded the double impact, she said.

Aborigine Eyewitnesses

Based on the new research, Abbott thinks the two craters were made by an object that split into pieces as it approached Earth.

To make a pair of craters this big in the seafloor's soft sediments, the original object must have been about 2,000 feet (600 meters) across before it broke up, she said.

Core samples from the region back up the case for such an impact, Abbott added. Previous research had found that the samples contain smooth, magnetic spherules, which were probably created when the object's explosive landing melted material and blasted it into the sky.

Furthermore, a 2004 paper in the journal Astronomy and Geophysics suggested that the circa-A.D. 500 global cooling event might have been caused by dust from an impact of approximately the size Abbott has now calculated for Carpentaria.

It's even possible the impact had eyewitnesses: Aboriginal rock art from the region seems to have recorded the event, although the researchers examining this art declined to discuss details until after their paper has been published.

Still, Duane Hamacher, a Ph.D. student at Macquarie University in Sydney not involved with the rock-art work, recently demonstrated that Aboriginal stories can be used to locate meteorite craters.

"Numerous examples of fiery stars falling from the sky and striking the earth, causing death and destruction, are found throughout Aboriginal Dreamings [spiritual folk stories] across Australia," Hamacher wrote on his blog.

"The descriptions seem to indicate that the events were witnessed, not simply 'made-up.'"

In findings yet to be published, Hamacher used one set of Aboriginal stories, along with images in Google Earth, to locate a 919-foot-wide (280-meter-wide) impact crater in Palm Valley, in Australia's Northern Territory.

Manach wrote: »

Offhand yes - except for the Amerindians: they had developed systems of glyphs and sticks with winding string to keep records (some of which still has not been deciphered. )

The Maya is a Mesoamerican civilization, noted for the only known fully developed written language of the pre-Columbian Americas, as well as for its art, architecture, and mathematical and astronomical systems. Initially established during the Pre-Classic period (c. 2000 BC to 250 AD), according to the Mesoamerican chronology, many Maya cities reached their highest state of development during the Classic period (c. 250 to 900 AD), and continued throughout the Post-Classic period until the arrival of the Spanish.
The Maya civilization shares many features with other Mesoamerican civilizations due to the high degree of interaction and cultural diffusion that characterized the region. Advances such as writing, epigraphy, and the calendar did not originate with the Maya; however, their civilization fully developed them. Maya influence can be detected from Honduras, Guatemala, Northern El Salvador and to as far as central Mexico, more than 1,000 km (620 mi) from the Maya area. Many outside influences are found in Maya art and architecture, which are thought to result from trade and cultural exchange rather than direct external conquest.

Dendrochronology raises questions about the nature of the AD 536 dust-veil event
M.G.L. Baillie
(Palaeoecology Centre, School of Geosciences, Queen's University, Belfast BT7 1NN, Northern Ireland, UK)
Abstract

New evidence is presented which shows the response of a wide grid of tree-ring chronologies to the dust-veil of AD 536, the effects of which were historically recorded in the Mediterranean and eastern Asia. The tree-ring evidence, particularly that from European oaks (Quercus), shows a two-stage response which raises questions about whether only a single massive eruption was involved. The observations from precisely dated tree-ring series set the agenda for the interpretation of forthcoming ice-core evidence across the AD 530s and 540s.