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Astronomers unravel a mystery of the Dark Ages
EurekAlert ^ | 3-Feb-2004 | Dr Derek Ward-Thompson

Posted on 02/03/2004 2:54:24 PM PST by ckilmer

Public release date: 3-Feb-2004

Contact: Dr Derek Ward-Thompson derek.ward-thompson@astro.cf.ac.uk 029-2087-5314 Cardiff University

Astronomers unravel a mystery of the Dark Ages Undergraduates' work blames comet for 6th-century "nuclear winter" 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Historical references from this period - known as the Dark Ages – are sparse, but what records there are, tell of crop failures and summer frosts.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.


TOPICS: Culture/Society; Extended News; Miscellaneous
KEYWORDS: 536ad; ad536; archaeology; arthurscomet; astronomy; baillie; cardiffuniversity; catastrophism; clube; comet; cuchulainn; darkages; economic; ggg; godsgravesglyphs; history; levy; lunarimpact; middleages; mikebaillie; napier; nuclearwinter; shoemaker; velikovsky
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To: blam
yeah I saw that report of the big space rock passing within 25,000 miles of earth...hmmm

Asteroid homing in for Earth's closest near-miss
http://thescotsman.scotsman.com/international.cfm?id=316162004
WILLIAM LYONS


ASTRONOMERS were last night waiting to see an asteroid the size of a house pass just 26,500 miles from Earth, the closest near-miss on record by a space rock.

The asteroid, which was first spied on Monday night and is travelling at ten miles a second, was not thought to be bright enough to spot with the naked eye, but should be close enough to be seen using a small telescope or binoculars.

Although 26,000 miles is roughly the Earth’s circumference, it is a mere whisker in space terms, said Dr John Davies, an astronomer at the Royal Observatory of Edinburgh. The last such near-miss was in December 1994, according to the Near Earth Object Information Centre (NEOIC) in Leicester.

Dr Davies said: "We are not scared of this one because we know exactly where it is going, but it is beyond doubt that the Earth has been struck by asteroids in the past and it is certain that it will be struck again in the future.

"The likelihood of an impact big enough to destroy a city is about once per 1,000 years, which is in the span of recorded human history."

Experts advising the NEOIC say the object, known to astronomers as 2004 FH, is no danger to Earth but will provide an opportunity for amateur astronomers to catch a glimpse of an asteroid. At its closest point, it will seem to be streaking over the southern Atlantic Ocean. Similar-sized asteroids are thought to come close to Earth on average once every two years, but have previously escaped detection.

Steve Chesley, an astronomer at NASA’s Jet Propulsion Laboratory, said: "The important thing is not that it’s happening, but that we detected it."

Astronomers found the asteroid during a routine survey using a pair of telescopes in New Mexico funded by NASA. "It immediately became clear it would pass very close by the Earth," Mr Chesley said.

Astronomers have not ruled out that the asteroid and our planet could meet again sometime in the future.

"Something this size would probably break up in the atmosphere into a bright fireball or a bright shooting star and then a few boulders would drop on to the ground somewhere," said Dr Davies.

"Small asteroids come into the earth’s orbit all the time, but we have become increasingly good at detecting them because of new technology, telescopes with better detectors that can cover more sky more quickly. Now it is possible to scan the whole sky in one night, where a couple of years ago that just wasn’t possible."

Until recently, no-one took the asteroid threat very seriously. But in 1994, the comet Shoemaker-Levy 9 hit Jupiter, creating an explosion the size of the Earth. It was the first time a collision between two astronomical bodies had been observed. Some astrologers warned that if Jupiter had been hit, the Earth could be next.

There has been pressure on the British and US governments to fund systematic skywatches to warn of potentially dangerous collisions. There is no dedicated programme searching for asteroids approaching the southern hemisphere, and NASA only looks for bodies bigger than a kilometre across.

An asteroid seven miles wide that hit the Yucatan peninsula 65 million years ago, in what is now Mexico, is widely accepted to have caused the extinction of the dinosaurs. And an asteroid about 60 yards across landed at Tunguska in Siberia in 1908, flattening trees for 13 miles and killing hundreds of reindeer.

Had that impact been in the centre of London, everything inside the M25 would have been destroyed.


61 posted on 03/18/2004 7:32:34 PM PST by ckilmer
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To: ckilmer
BTTT
62 posted on 03/18/2004 7:34:05 PM PST by Fiddlstix (This Space Available for Rent or Lease by the Day, Week, or Month. Reasonable Rates. Inquire within.)
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To: dg62; All
"After the event of 536-541AD, the lights truly go out. After another hundred or so years, not even Kings could read or write."


A comet must have hit the US public school system then!


63 posted on 04/25/2004 1:01:51 AM PDT by mdmathis6 (The Democrats must be defeated in 2004...." MDMATHIS6, The Anti-Democrat")
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Just updating the GGG information, not sending a general distribution.
Please FREEPMAIL me if you want on, off, or alter the "Gods, Graves, Glyphs" PING list --
Archaeology/Anthropology/Ancient Cultures/Artifacts/Antiquities, etc.
The GGG Digest
-- Gods, Graves, Glyphs (alpha order)

64 posted on 05/18/2005 6:16:05 PM PDT by SunkenCiv (FR profiled updated Tuesday, May 10, 2005. Fewer graphics, faster loading.)
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Catastrophism

65 posted on 03/26/2006 8:24:56 PM PST by SunkenCiv (Yes indeed, Civ updated his profile and links pages again, on Monday, March 6, 2006.)
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Astronomy & Geophysics
Volume 45 Issue 1 Page 1.23 - February 2004
doi:10.1046/j.1468-4004.2003.45123.x
Volume 45 Issue 1

Comet impact
A comet impact in AD 536?
Emma Rigby1, Melissa Symonds2 and Derek Ward-Thompson2

Emma Rigby, Melissa Symonds and Derek Ward-Thompson review the evidence for the possibility that a comet may have impacted the Earth in historical times, and discuss the size of the putative comet.

Abstract

A global climatic downturn has previously been observed in tree-ring data associated with the years AD 536–545. We review the evidence for the explanation of this event which involves a comet fragment impacting the Earth and exploding in the upper atmosphere. The explosion would create a plume, such as was seen during the impact of comet Shoemaker-Levy 9 with Jupiter. The resulting debris deposited by the plume on to the top of the atmosphere would increase the opacity and lower the temperature. We calculate the size of the comet required, and find that a relatively small fragment of only about half a kilometre in diameter could be consistent with the data. We conclude that plume formation is a by-product of small comet impacts that must be added to the list of significant global hazards posed by near-Earth objects.

Article published online 28 Jan 2004

Affiliations

1Cardiff University, UK (now at Edinburgh University, UK)2Cardiff University

The authors thank Mike Baillie, Mark Bailey, Martin Johnson, Ted Johnson-South and David Williams for interesting and helpful discussions.

To cite this article
Rigby, Emma, Symonds, Melissa & Ward-Thompson, Derek (2004)
A comet impact in AD 536?.
Astronomy & Geophysics 45 (1), 1.23-1.26.
doi: 10.1046/
j.1468-4004.2003.45123.x

Blackwell Synergy® is a Blackwell Publishing, Inc. registered trademark

· Catastrophism ping list · join · view topics · view or post blog · bookmark ·

66 posted on 01/11/2007 9:18:07 AM PST by SunkenCiv ("I've learned to live with not knowing." -- Richard Feynman https://secure.freerepublic.com/donate/)
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To: Cailleach

ping


67 posted on 01/11/2007 9:21:29 AM PST by kalee (No burka for me....EVER!)
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To: blam
I've read that the kings had writers and readers and the writers could not read and the readers could not write. (Doesn't make a lot of sense but, that's what I read)

East German joke:

Q: Why do Stasi agents travel in threes?
A: One who can read, one who can write, and one to keep an eye on the two dangerous intellectuals.

68 posted on 01/11/2007 9:24:36 AM PST by steve-b (It's hard to be religious when certain people don't get struck by lightning.)
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To: dg62

The eastern half of the Roman Empire was still pretty much intact, and in fact had reconquered parts of the western half. However, the reconquests never really took root (except perhaps for the north African provinces, which they held until the Arabs came through a century later).


69 posted on 01/11/2007 9:33:06 AM PST by steve-b (It's hard to be religious when certain people don't get struck by lightning.)
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To: dg62
>>>>>>After the event of 536-541AD, the lights truly go out. After another hundred or so years, not even Kings could read or write. <<<<<<<<

This is something we all learned in school. However, some ten years ago, before widespread internet I have been told by a medieval scholar that this is not true, that written records of "dark ages" do exist but are left to linger in the shade, or deliberatelly put aside.

Can anyone elaborate if this is true or not?

70 posted on 01/11/2007 9:39:06 AM PST by DTA (Mr. President., Condy is asleep at the wheel !)
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To: dg62
>>>>>>After the event of 536-541AD, the lights truly go out. After another hundred or so years, not even Kings could read or write. <<<<<<<<

This is something we all learned in school. However, some ten years ago, before widespread internet I have been told by a medieval scholar that this is not true, that written records of "dark ages" do exist but are left to linger in the shade, or deliberatelly put aside.

Can anyone elaborate if this is true or not?

71 posted on 01/11/2007 9:39:07 AM PST by DTA (Mr. President., Condy is asleep at the wheel !)
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To: RightOnline
>>>>>Yep........I remember it, too. Cold as all hell, it was.<<<<<<

RightOnline, just to remind you: don't lose your head. There can be only one. :-)

72 posted on 01/11/2007 9:44:06 AM PST by DTA (Mr. President., Condy is asleep at the wheel !)
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To: blam
given to Mohammad by Abraham

Many centuries separate those two entities.

73 posted on 01/11/2007 10:01:00 AM PST by American_Centurion (No, I don't trust the government to automatically do the right thing.)
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To: DTA
"Can anyone elaborate if this is true or not? "

Professor Mike Baillie in his excellent Book "Exodus To Arthur" makes a good case. See a review of his book below:

EXODUS TO ARTHUR - MIKE BAILLIE [REVIEW]

The great religious myths of the past seem so extraordinary to us - Moses leading the Jews on their exodus from Egypt, the ancient legend of Atlantis, the Chinese tales of dragons battling across the sky. Are these the stuff of legend or were ancient scholars doing the best they could to describe events beyond their comprehension? Using modern scientific knowledge, can we discover what was really happening?

Professor Mike Baillie is an expert in the field of dendrochronology, that is, tree-ring dating, at Queen's University, Belfast. Over the past 100 years, scientists across the globe have been reconstructing a global chronology of tree growth going back 10,000 years. Because tree growth varies from year to year based on environmental conditions, it is possible to study the chronologies to build up a picture of the climate that existed when these trees were alive. Using this method, scholars have identified evidence of alarming environmental events in the past, affecting the entire planet, with profound consequences for the human groups living at those times.

Allied to this work, an independent line of investigation into historical volano activity seemed to indicate a possible cause of these climatic shocks. By studying Greenland ice cores for acid layers deposited after volcanic eruptions, scientists can give broad dates for significant past eruptions. Interestingly, several of the broad dates given matched up within the timeframe of the environmental shocks recorded by tree ring events. The best early candidate for an example of this volcano/catastrophe scenario was the massive eruption on the Mediterranean island of Thera, circa 1450 BC which had severe effects on the advanced Minoan civilization based on nearby Crete. This eruption is generally considered to be the best 'scientific' explanation for the legend of the lost city of Atlantis.

However, problems with this scenario began to build with the identification of a major tree ring event cenetred on 1627 BC. This conflicted with the date of 1390 (+- 50) BC which ice-core workers had identified for a major eruption. Convential Egyptian archaeology also dates the Thera eruption at 1450 BC. What was the true story? Did Thera erupt in 1450 or 1627? Was another volcano to blame for the 1390 ice-core layer? Or was something else the cause of the 1627 tree-ring event?

This led Baillie to explore other sources of knowledge for the 2nd millenium BC, for instance in the middle of the millenium the Xia dynasty in China came to an end, being replaced by the Shang dynasty. From the tree rings we know that this was a time of climactic uncertainty. The dust veil thrown up by a volcanic eruption would mean cold weather, bad harvests, famine and even plague. For an king proclaiming that he rules with a Mandate for Heaven, this is a recipe for overthrow.

The Old Testament also records the Exodus of the Jewish people from Egypt, conventionally dated at 1250 BC. This was a time of plagues, and mysterious signs in the sky. By pushing out the timeframes for these events - it is possible for the archeological dates to be incorrect by a few hundred years, can we find something to link them together and give a fuller explanation?

This is where Baillie brings the subtitle of the book into play, 'Catastrophic Encounters With Comets'. A strike by cometrary debris could produce similar consequnces to a volcanic eruption - debris would block out the sun, cooling the climate; geological disturbances may also be possible. At Tunguska in 1908 a lump of cometray debris exploded above Siberia with a huge fireball, great noise and earthquakes. As it was an airburst explosion, the only evidence of the event was a huge patch of flattened forest.

If an ancient observer, and not a modern scientist had witnessed the Tunguska explosion, how would he have described it? In Exodus the Jews are led to freedom by the Angel of the Lord, standing between Earth and Heaven, having a drawn sword in his hand. Chinese myths record battles in the sky between dragons. Is this how our ancestors would visualise a comet? We should not underestimate our ancestors, nor the scope of their activities.

Baillie continues with this theme by focusing on another climactic event around 540 AD, which is clearly recorded in tree rings, but not in the ice core layers - strongly suggesting a cometary strike, and not as some have suggested, that the CIA has been covering up evidence of alien visitation! A cold spell at this time had tremendous consequences for humanity. Hundreds of thousands died as Constantinople was ravaged by plague, and the last hope of the Roman Empire crumbled. The myths surrounding King Arthur and his wizard Merlin can also be re-interpreted with comets in mind, as can the story of Beowulf and Grendel. One of the suggested dates for the death of the quasi-mythical Arthur is 539 AD.

At this point, you can see that much of the evidence that Baillie has collected in support of his cometary hypothesis requires re-interpretation, not just of myths and religious texts, but also of conventional archeological dates from Egypt and China. This could be justified if we had stronger evidence for cometary strikes at those times, by but Baillie's own admission, with comets we have a possible major vector for environmental and human change that is to all intents invisible. Most strikes would result in airburst explosions, traces of which would only be recorded in ancient texts. I would imagine that if another Tunguska event is observed by modern scientists those ancient texts will be looked at more closely, let us hope we are lucky again and it occurs in a deserted area like Siberia.

The idea that environmental events, of which comets are but one example, can have profound consequences for humanity and human history, is an idea whose time has clearly come though. Baillie persuasively argues this 'minimal' case for comets. Historians record cultural collapses and population movements since the end of the last Ice Age. Astronomers tell us that Tunguska class strikes would have happened frequently over the past 10,000 years. "In a great whodunnit of history astrophysicists have the 'gun' and archeologists-historians have the 'corpse', but no one suspects a 'shooting'. The ideas of catastrophism and environmental determinism have been so marginalized that archeologists-historians do not accept comets as even a possible vector of historical change." It seems highly implausible however, that humans have been lucky enough to escape without consequence events like Tunguska.

Unfortunately Baillie then goes on to undermine attempts to have his hypothesis taken seriously by suggesting that one way we can protect ourselves from the terrible consequences of impacts is to 'conform to the rules of the Lord of Creation and ask to be spared'. This one small paragraph opens up such a can of worms that I am at a loss to understand why Baillie would even think about putting it in.

Overall then, this book is an interesting read, although perhaps a shorter, more solidly based article would be a better introduction to the topic. I think that biblical scholars and students of ancient myths and art would find it of special interest in trying to understand what was actually being described by our ancestors. I would not however, feel comfortable arguing anything other than Baillie's 'minimal' hypothesis with anyone.

74 posted on 01/11/2007 10:07:52 AM PST by blam
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To: American_Centurion
"Many centuries separate those two entities."

Thanks. I've learned that since the original posting.

75 posted on 01/11/2007 10:09:29 AM PST by blam
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To: ckilmer

Gentlemen, you are correct. The best seller of all time reports about a coming event of this very type. On the great and terrible Day of the Lord two comets or asteroids are going to hit modern day Iraq and the Mediterranean Sea. Straight out of the Book of Revelation.


76 posted on 01/11/2007 10:24:41 AM PST by STD (Rough Sailing Directly Ahead)
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To: dg62
After the event of 536-541AD, the lights truly go out. After another hundred or so years, not even Kings could read or write.

I don't think the non-Roman kings could either, even while the empire still lasted. In any case, pinning the Middle Ages on this one event seems highly speculative to me, considering that Rome had been declining since the 3rd century and, indeed, had finally evaporated from western Europe nearly a century before. The Byzantine Empire trucked on strong for another thousand years, in spite of this event, and if literature withered into the monasteries in a form that usually represented itself only in saints' lives and biblical commentaries, it just continued a trend that had been ongoing for centuries previous. Very little important Roman or Greek literature was written after the 2nd century.

77 posted on 01/11/2007 10:25:20 AM PST by SpringheelJack
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To: DTA
Can anyone elaborate if this is true or not?

True. There are direct accounts of the period, especially in the Byzantine histories. They record the Justinian plague at this time, but no comet. The records for NW Europe are somewhat more sparse. Perhaps most applicable to this thread is Gregory of Tours work, Decem Libri Historiarum, a chronicle of the Merovingian kings, written c.575-594 AD. It makes no mention of the proposed comet or cold winter, which would have occurred around Gregory's birth. A contemporary account of events in Britain are filled with doom and gloom about the invading Saxons, but no famine winter.

I am unaware of any contemporary account of a major celestial event, such as a comet strike.

78 posted on 01/11/2007 10:46:03 AM PST by LexBaird (98% satisfaction guaranteed. There's just no pleasing some people.)
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To: blam
"...a fragment from this impact was given to Mohammad by Abraham and is the stone the Islamists presently worship in Mecca)"

Ummm.......seeing as how a few thousand years separate Abraham and Mohammed......ummm........... I don't think so.

79 posted on 01/11/2007 3:49:17 PM PST by RightOnline
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To: RightOnline

See my post #75.


80 posted on 01/11/2007 4:23:47 PM PST by blam
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