by Robert Roy Britt, Senior Science Editor,
Space.com, 13 November 2001
"...and the seven judges of hell... raised their
torches, lighting the land with their livid flame. A stupor of
despair went up to heaven when the god of the storm turned daylight
into darkness, when he smashed the land like a cup."
So says an account of the Deluge from the Epic of Gilgamesh,
circa 2200 BC.
Similar but considerably less powerful versions of
the events which some scientists say brought down the world's first
civilisations happen frequently, when meteors hit the planet.
Biblical stories, apocalyptic visions, ancient art and
scientific data all seem to intersect at around 2350 BC, when one or
more catastrophic events wiped out several advanced societies in
Europe, Asia and Africa.
Increasingly, some scientists suspect comets and their
associated meteor storms were the cause. History and culture provide
clues: icons and myths surrounding the alleged cataclysms persist in
cults and religions today and even fuel terrorism.
And a newly found two mile-wide crater in Iraq, spotted
serendipitously in a perusal of satellite images, could provide a
smoking gun. The crater's discovery, which was announced in a recent
issue of the journal, Meteoritics & Planetary Science, is a
preliminary finding. Scientists stress that a ground expedition is
needed to determine if the landform was actually carved out by an
Yet the crater has already added another chapter to an
intriguing overall story that is, at best, loosely bound. Many of
the pages are washed away or buried. But several plot lines converge
in conspicuous ways.
Too many coincidences
Archaeological findings show that in the space of a few
centuries, many of the first sophisticated civilisations
An artist's impression of a large meteor entering Earth's atmosphere
A detailed collection of features and king lists covering all of this
The Old Kingdom in Egypt fell into ruin. The Akkadian
culture of Mesopotamia, possibly the world's first empire,
collapsed. Settlements in the ancient Levant, gone. Mesopotamia,
Earth's original breadbasket, dust .
At around the same time, a period called the Early Bronze Age,
apocalyptic writings appeared, fuelling religious beliefs that
The Epic of Gilgamesh describes the fire, brimstone and flood of
possibly mythical events. Omens predicting the Akkadian collapse
preserve a record that "many stars were falling from the sky." The
"Curse of Akkad," dated to about 2200 BC, speaks of "flaming
potsherds raining from the sky."
Roughly 2000 years later, the Jewish astronomer Rabbi bar
Nachmani created what could be considered the first impact theory:
that Noah's Flood was triggered by two "stars" that fell from the
sky. "When God decided to bring about the Flood, He took two stars
from Khima, threw them on Earth, and brought about the Flood."
 While the Old Kingdom did
collapse at the end of the 22nd century BC, and there was a
general climate-induced collapse in Mesopotamia at around the
same time, the evidence for the Levant is much less clear due to
the fact that there is little documented evidence from many of
the small city states which existed there. The writer uses the
term 'ancient Israel' instead of the Levant, which makes the
claim seem less credible, as that state did not exist at all
before the late eighteenth century BC [Ed].
Another thread was woven into the tale when, in 1650, the Irish
Archbishop James Ussher mapped out the chronology of the Bible, a
feat that included stringing together all the "begats" to count
generations, and put Noah's great flood at 2349 BC .
All coincidence? A number of scientists don't think so.
Mounting hard evidence collected from tree rings, soil layers
and even dust that long ago settled to the ocean floor indicates
there were widespread environmental nightmares in the Near East
during the Early Bronze Age: abrupt cooling of the climate, sudden
floods and surges from the seas, huge earthquakes.
Comet as a culprit
In recent years, the fall of ancient civilisations has come to
be viewed not as a failure of social engineering or political might
but rather the product of climate change and, possibly, heavenly
happenstance. As this new thinking dawned, volcanoes and earthquakes
were blamed at first. More recently, a 300-year drought has been the
But now more than ever, it appears a comet could be the culprit.
One or more devastating impacts could have rocked the planet,
chilled the air, and created unthinkable tidal waves, ocean waves
hundreds of feet high. Showers of debris wafting through space,
concentrated versions of the dust trails that create the more recent Leonid
would have blocked out the sun and delivered horrific rains of fire to
Earth for years.
 There were certainly several
large-scale floods in Ancient Mesopotamia, with perhaps one of
the worst being that which took place between about 2900-2750
BC. This was probably the legendary flood of Sumerian
literature, which was handed down through the generations to
become Noah's great flood, but it may have carried a memory of a
far earlier and greater flood: that of the Mediterranean
breaking into the Black Sea in about 5600 BC [Ed].
So far, the comet theory lacks firm evidence, such as the
discovery of a crater.
Now, though, there is this depression in modern Iraq. It was found
accidentally by Sharad Master, a geologist at the University of
Witwatersrand in South Africa, while studying satellite images.
Master says the crater bears the signature shape and look of an
impact caused by a space rock.
The finding has not been developed into a fully-fledged
scientific paper, however, nor has it undergone peer review.
Scientists in several fields were excited by the possibility, but
they expressed caution about interpreting the preliminary analysis
and said a full scientific expedition to the site needs to be
mounted to determine if the landforms do in fact represent an impact
Researchers would look for shards of melted sand and telltale
quartz that had been shocked into existence. If it were a comet, the
impact would have occurred on what was once a shallow sea,
triggering massive flooding following the fire generated by the
object's partial vaporisation as it screamed through the atmosphere.
The comet would have plunged through the water and dug into the
If it proves to be an impact crater, there is a good chance it
was dug from the planet less than 6,000 years ago, Master said,
because shifting sediment in the region would have buried anything
Arriving at an exact date will be difficult, researchers said. "It's an exciting crater if it really is of impact origin," said
Bill Napier, an astronomer at the Armagh Observatory.
Napier said an impact that could carve a hole this large would
have packed the energy of several dozen nuclear bombs. The local
effect: utter devastation.
"But the cultural effect would be far greater," Napier said in
an e-mail interview. "The event would surely be incorporated into
the world view of people in the Near East at that time and be handed
down through the generations in the form of celestial myths."
Drought in the middle east is a leading cause of ancient instances
Napier and others have also suggested that the swastika, a
symbol with roots in Asia stretching back to at least 1400 BC,
could be an artist's rendering of a comet, with jets spewing
material outward as the head of the comet points earthwards.
But could a single impact of this size take down civilizations
on three continents? No way, most experts say.
Napier thinks multiple impacts, and possibly a rain of other
smaller meteors and dust, would have been required. He and his
colleagues have been arguing since 1982 that such events are
possible. And, he says, it might have happened right around the time
the first urban civilisations were crumbling.
Napier thinks a comet called Encke, discovered in 1786, is the
remnant of a larger comet that broke apart 5,000 years ago. Large
chunks and vast clouds of smaller debris were cast into space.
Napier said it's possible that Earth ran through that material
during the Early Bronze Age.
The night sky would have been lit up for years by a
fireworks-like display of comet fragments and dust vaporising upon
impact with Earth's atmosphere. The sun would have struggled to
shine through the debris. Napier has tied the possible event to a
cooling of the climate, measured in tree rings, that ran from
Though no other craters have been found in the region and
precisely dated to this time, there is other evidence to suggest the
scenario is plausible. Two large impact craters in Argentina are
believed to have been created sometime in the past 5,000 years.
Benny Peiser, a social anthropologist at Liverpool John Moores
University in England, said roughly a dozen craters are known to
have been carved out during the past 10,000 years. Dating them
precisely is nearly impossible with current technology. And, Peiser
said, whether any of the impact craters thought to have been made in
the past 10,000 years can be tied back to a single comet is still
The Leonid comet shower photographed on 18 November 1999
But he did not discount Napier's scenario.
"There is no scientific reason to doubt that the break-up of a
giant comet might result in a shower of cosmic debris," Peiser said.
He also points out that because Earth is covered mostly by deep
seas, each visible crater represents more ominous statistical
possibilities. "For every crater discovered on land, we should expect two
oceanic impacts with even worse consequences," he said.
Tidal waves generated in deep water can rise even higher when they
reach a shore.
Peiser studies known craters for clues to the past. But he also
examines religions and cults, old and new, for signs of what might
have happened way back then.
"I would not be surprised if the notorious rituals of human
sacrifice were a direct consequence of attempts to overcome this
trauma," he says of the South American impact craters.
"Interestingly, the same deadly cults were also established in the
Near East during the Bronze Age."
The impact of comets on myth and religion has reverberated
through the ages, in Peiser's view.
"One has to take into consideration apocalyptic religions [of
today] to understand the far-reaching consequences of historical
impacts," he says. "After all, the apocalyptic fear of the end of
the world is still very prevalent today and can often lead to
fanaticism and extremism."
An obsession with the end of the world provides the legs on
which modern-day terrorism stands, Peiser argues. Leaders of
fundamentalist terror groups drum into the minds of their followers
looming cataclysms inspired by ancient writings. Phrases run along
these lines: a rolling up of the sun, darkening of the stars,
movement of the mountains, splitting of the sky...
It is in the context of such apocalyptic religions that a large
meteorite, enshrined in the Kaba in Mecca, became the most feared
and venerated object of the Islamic faith, Peiser said.
A tidal wave was the cause of the destruction of Minoan Crete in the
fifteenth century BC
By using such language, radical fundamentalist leaders instil
"absolute commitment and fanaticism into their followers," Peiser
said. "Once you believe that the end is imminent and that your
direct action will hasten the coming of end times, every atrocity is
No smoking gun yet
Despite the excitement of the newfound hole in the ground in
Iraq, it is still far from clear why so many civilisations collapsed
in such a relatively short historical time frame. Few scientists,
even those who find evidence to support the idea, are ready to
categorically blame a comet.
French soil scientist Marie-Agnes Courty, who in 1997 found
material that could only have come from a meteorite and dated it to
the Early Bronze Age, urged caution on drawing any conclusions until
a smoking gun has been positively identified.
"Certain scientists and the popular press do prefer the idea of
linking natural catastrophes and societal collapse," Courty said.
Multiple cosmic impacts are an attractive culprit though,
because of the many effects they can have, including some found in
real climate and geologic data. The initial impact, if it is on
land, vaporises life for miles around. Earthquakes devastate an even
wider area. A cloud of debris can block out the sun and alter the
climate. The extent and duration of the climate effects is not known
for sure, because scientists have never witnessed such an event.
It might not have taken much. Ancient civilisations, which
depended on farming and reliable rainfall, were precarious.
Mike Baillie, a professor of palaeoecology at Queens University
in Belfast, figures it would have taken just a few bad years to
destroy such a society.
Even a single comet impact large enough to have created the
Iraqi crater, "would have caused a mini-nuclear winter with failed
harvests and famine, bringing down any agriculture-based populations
which can survive only as long as their stored food reserves,"
Baillie said. "So any environmental downturn lasting longer than
about three years tends to bring down civilisations."
A 1994 image of Comet Borrelly on one of its swings around the sun
Other scientists doubt that a single impact would have altered
the climate for so long.
Lessons for tomorrow
Either way, there is a giant scar on the planet, near the cradle
of civilisation, that could soon begin to provide some solid
answers, assuming geologists can get permission to enter Iraq and
conduct a study.
"If the crater dated from the third millennium BC, it would be
almost impossible not to connect it directly with the demise of the
Early Bronze Age civilisations in the Near East," said Peiser.
Perhaps before long all the cometary traditions, myths and
scientific fact will be seen to converge at the Iraqi hole in the
ground for good reason. Understanding what happened, and how
frequent and deadly such impacts might be, is an important tool for
researchers like Peiser who aim to estimate future risk and help
modern society avoid the fate of the ancients.
"Paradoxically, the Hebrew Bible and other Near Eastern
documents have kept alive the memory of ancient catastrophes whose
scientific analysis and understanding might now be vital for the
protection of our own civilisations from future impacts," Peiser
Early societies which relied upon rain-fed farming practices were at
the mercy of the elements