Kevin A. & Patrick J. Casey are the American authors of a series of papers currently available on the academia.edu website(a), which are concerned with a globally catastrophic event that occurred 13,000 years ago. providing them with a title of ’13K Theory’. The kernel of their theory is that originally the Earth had two moons that at some later point collided, producing our current Moon, while the remnant of the second one eventually exploded over North America kick-starting what we refer to as the cooler Younger Dryas period.
They claim that this event wiped out megafauna, altered the Earth’s axis and created our mountains, the Earth being generally flat before the dramatic episode! They are adamant that it was not a comet or asteroid that caused the devastation, and so clash with the work of Richard Firestone and his colleagues.
Their final paper is entitled Atlantis Revisited(b), in which they nominate Rockall as being ‘by far’ the most likely location of Atlantis. They also claim that the war between the Atlanteans and the Greeks took place before the 13K Event. Enjoy.
Dr Michel-Alain Combes (1942- ) is a French amateur astronomer with a PhD in astronomy from the Université Pierre et Marie Curie (Paris VI). For forty years he has studied impact catastrophism and published his views in his book, La Terre Bombardée (The Bombarded Earth). His extensive website(a) endeavours to combine history, myth and science and includes a reference to Atlantis, as well as a kind mention of this site. His book can also be read on his site (French).
Combes delivered a paper in English(b) to a 2008 Conference in Paris entitled; The Apocalypse of the Year 10,000 BC – Myth or Reality? It has been proposed that this event may have created the Carolina Bays and destroyed Atlantis as proposed by Otto Muck.
Furthermore, it has also been linked to the onset of the mini ice age known as the Younger Dryas as described by Firestone, West and Warwick-Smith in their book The Cycle of Cosmic Catastrophes.
In 1992, Asteroid ‘3446 Combes’ was named in his honour.
(a) http://www.astrosurf.com/macombes/index.html (French)
The Holocene Impact Working Group (HIWG)(a) was created by researchers into different aspects of geosciences, who believe that cometary impacts were more frequent during the recent past than generally accepted. It is concerned with the growing number of impact craters being discovered and the evidence of consequent mega tsunamis. Its membership includes Mike Baillie, Richard Firestone and Bruce Masse(b).
The New York Times reviewed the work of the HIWG in 2006(c).
Younger Dryas also known as Dryas III was a mini Ice Age that lasted from around 10,700 BC until around 9600 BC. It is named after a flower that flourished during this relatively short period. In Ireland the period is known as the Nahanagan Stadial and in Britain as the Loch Lomond Stadial. For about thirteen hundred years the glaciers had been slowly retreating until within a short time-span temperatures dropped and they began to advance again. The cause of this cooling is not absolutely clear. One view is that a sudden release into the North Atlantic of vast quantities of fresh water that had been contained by huge ice dams is assumed to have closed down the Gulf Stream, resulting in a twelve hundred year lowering of global temperatures. There is evidence that the change only took one or two decades. The same threat is said to exist today with the possibility of the melting of the Greenland ice cap.
The most recent theory, by Firestone, West and Warwick-Smith, links the onset of the Younger Dryas with the explosion of a comet over North America that led to the extinction of many species, the collapse of the Clovis culture(a)(b) as well as the creation of the Carolina Bays.
A 2014 paper(g) entitled Nanodiamond-Rich Layer Across Three Continents Consistent with Major Cosmic Impact at 12,800 Cal BP by Charles R. Kinzie et al., has developed further the idea of this event being associated with the Younger Dryas. In a similar vein is an article(h) from Megan Gannon.
A recent application of archaeoastronomy by Martin Sweatman and Dimitrios Tsikritsis led them to conclude that the carved symbols at Göbekli Tepe recorded an encounter involving the explosion or impact of part of Encke’s Comet around 13,000 years ago, which triggered the Younger Dryas Event that provided the impetus for the Neolithic Revolution. Sweatman later expanded their work in his book Prehistory Decoded  and in an article on the Ancient Origins website(m).
Kevin A. & Patrick J. Casey maintain that a globally catastrophic event occurred 13,000 years ago(l). The kernel of their theory is that originally the Earth had two moons that at some later point collided, producing our current Moon, while the remnant of the second one eventually exploded over North America kick-starting what we refer to as the cooler Younger Dryas period. They are adamant that it was not a comet or asteroid that caused the devastation, and so clash with the work of Richard Firestone and his colleagues.
In 2015 a paper constraining the impact date to within 100 years using Bayesian statistical analyses, now proposed as 12,835 -12,735 years ago(j).
Coincidentally, Professor Emilio Spedicato independently arrived at the conclusion that it was a cometary impact in the North Atlantic that was responsible for the Younger Dryas. Subsequently, when temperatures rose again it resulted in the flooding of vast areas of low-lying landmasses that in Spedicato’s opinion, included Atlantis, which he locates in Hispaniola.
Conflicting evidence regarding the possibility of the Younger Dryas being caused by such an impact is impartially outlined on the internet(c).
December 2014 saw Graham Hancock raising the issue of a cometary cause for the Younger Dryas and its possible association with ancient Egypt(f).
The November 2013 issue of the BBC Focus magazine (p.30) had a brief article on the impact theory, noting that the northern hemisphere saw a drop of as much as 15°C around 11,000BC. In the absence of a suitable impact crater there is still much scientific scepticism(d).
However in early 2017, further possible evidence of an impact at the start of the Younger Dryas was offered by a team led by Christopher Moore of the University of South Carolina, when they identified a distinct layer of platinum in the soil that coincided with the start of YD. Commenting on this anomaly Moore noted that “Platinum is very rare in the Earth’s crust, but it is common in asteroids and comets.”(i)
In early 2018, two papers were published online(k), reinforcing the YD impact theory and adding evidence that the event resulted in a conflagration that “may have consumed – 10 million km2, or – 9% of Earth’s terrestrial biomass”.*Related to this is a paper by Andrew Collins that draws attention to the ‘Usselo horizon’, a charcoal-rich layer of between 1 and 8 inches, found on all continents, indicating widespread fires, now dated to 12,900 years ago(n).*
Ice cores from Greenland indicate a further cooling period circa 6200 BC that may be related to the abandonment of many Neolithic settlements during this period. Other periods of abrupt climate change have been identified from 3800 BC to 3500 BC and 2800 BC to 2000 BC.
The fact that Plato’s apparent date for the demise of Atlantis, circa 9600 BC, roughly corresponds with the current, best estimate for the date of the Younger Dryas is interesting but unfortunately not conclusive proof of any direct connection. In the absence of any supportive archaeological evidence, a linkage between Atlantis and the Younger Dryas will have to remain a matter of faith rather than fact. Interesting but inconclusive.
Recent discoveries in northern Sudan of dozens of skeletons, the majority of whom were apparently killed by flint-tipped arrows, have led to the suggestion(e) they were the result of food shortages resulting from the Younger Dryas that in turn led to warfare over diminished food availability.
(c) http://blogs.nicholas.duke.edu/thegreengrok/climatedebate/ (offline Dec. 2016) See: https://web.archive.org/web/20130310032309/http://blogs.nicholas.duke.edu/thegreengrok/climatedebate/
R. Cedric Leonard (1934- ) is from Oklahoma and has worked as an electronic technician, initially in the U.S. Navy and later in private industry, from which he retired in 1990. He has studied Comparative Religion, Sanskrit and Classical Greek and has a B.A. in Anthropology from the University of Oklahoma. He is also self-taught in Egyptian, Canaanite and Phoenician inscriptions. He has also speculated on the possibility of the Phoenician alphabet having its origins in Atlantis and possibility of a connection with the Glozel Tablets(c).
His Sanskrit studies led him to investigate stories of the vimanas or ancient Hindu flying machines. He has produced several booksand scientific papers on the subject of Atlantis and ancient India. He has also written on the existence of UFO’s in ancient Egypt(d), Mesopotamia(h) and the Bible, particularly the Book of Ezekiel(e). He has also produced a paper(f) about archaeological mysteries in general.
Although retired, he still maintains his very interesting Atlantis website(a), which covers a range of subjects including connections between Cro-Magnon Man and ancient Egypt with Atlantis.* Unfortunately, his website has now (2019) gone offline.*
He locates Atlantis along The Mid-Atlantic Ridge and offers geological, mythological, linguistic and paleontological evidence to support this idea and for its destruction following worldwide catastrophes around 10000 BC. He has also written a paper(g) on the asteroid/comet impact around the same time, which created the Carolina Bays and its possible connection with the destruction of Atlantis. This encounter was brought to the notice of a wide audience by Richard Firestone and his colleagues by their book, The Cycle of Cosmic Catastrophes.
Leonard himself recognises that his belief in prehistoric flying machines may lead some readers to dismiss his carefully thought out theory on Atlantis, but he is adamant that both existed. Nevertheless, it is fair to say that Leonard is one of the few writers on the subject who has produced original material to support the idea of Atlantis’ existence.
Some of Leonard’s work can be found plagiarised on the Internet, most blatantly by the artist, Charles Alexander Moffat(b).
* (a) www.atlantisquest.com (offline Jan.2019)*
(c) http://www.atlantisquest.com/glozel.html (Offline March 2018) See:http://s8int.com/articles/260/19/sophis26.html
*(d) http://www.atlantisquest.com/Firecircle.html (Offline March 2018) See related site: https://ancient-code.com/arrival-sky-gods-ancient-egyptian-papyrus-details-mass-ufo-sighting/
(e) http://www.atlantisquest.com/Ezekiel.html (offline March 2018) See: https://pathwaytoascension.wordpress.com/2013/01/22/the-wheels-of-ezekiel-was-it-a-space-ship-r-cedric-leonard-ph-d/
(g) http://www.atlantisquest.com/Asteroid.html (offline March 2018)
(h) http://www.atlantisquest.com/Sifrala.html (offline March 2018) See: Archive 2881
Richard Firestone together with his co-authors Allen West and Simon Warwick-Smith have written one of the most impressive accounts of a cosmic collision that led to the extinction in North America of large mammals such as the mammoth and sabre-toothed tiger and the concurrent disappearance of the Clovis people at the end of the last Ice Age. Their impact theory also offers a credible explanation for the Carolina Bays. However, they propose that this collision had catastrophic global consequences. The three scientists are prepared to consider the possibility that Plato’s Atlantis story, however garbled, is related to the same episode[0110.328]..
Since the publication of their book some evidence(a) has emerged that would appear to conflict with their core thesis. This criticism appears to be gaining support according to a May 2011 report(b)(d). However, in September 2012 it was reported that further intensive investigation has revealed flaws in the evidence gathering of Firestone’s critics(f). The interdisciplinary team of scientists from seven U.S. institutions concluded that “a disregard of three critical protocols, including sorting samples by size, explains why a group challenging the theory of a North American meteor-impact event some 12,900 years ago failed to find iron- and silica-rich magnetic particles in the sites they investigated.”
Strong resistance to the Firestone claims continued into 2013 when the Royal Holloway and the Sandia National Laboratories along with 13 other universities across the United States and Europe mounted further challenges(g).
The waters were muddied further when it was revealed that Allen West was formerly known as Allen Whitt, who was convicted in California of posing as a state-licensed geologist(b) and fined $4,500! He legally changed his name in 2006. His respected co-authors were apparently unaware of his history and as a consequence of West’s central role in the data gathering, the hypothesis is considered by some to be tainted. This may be a case of shooting the messenger instead of the message, a view discussed at length on the Internet(e).A spirited defence of both West in particular and the theory of the team in general has also been written(c) and should be read in order to get a more balanced view of this particular controversy.
The core debate has rumbled on ever since. In July 2015 the University of California, Santa Barbara, released the results(h) of research, led by James Kennett, which again supported the impact theory and “has narrowed the date to a 100-year range, sometime between 12,835 and 12,735 years ago.”
The battle has continued, apparently inconclusively, with more papers being published by all sides. July 2018 saw an update of the controversy published on the Science News website(i), with no sign of the war ending.
*Nevertheless, in late 2019, further evidence has emerged that appears supportive of Firestone’s theory. Where previously nanodiamonds were an important feature in the presentation of his ideas the latest studies focus on platinum as an important marker(j).*
Inspiration resulting from an interview with Firestone led Kevin Curran to a study that ended with the publication of Fall of a Thousand Suns, in which he investigates the effect of extraterrestrial encounters on the development of early religious beliefs.
The Destruction of the Athenian Army, together with that of Atlantis, as related by Plato, (Timaeus 25d) makes no sense if the whole story is allegedly offered as a morality tale, where the wicked and corrupt Atlanteans are destroyed because of their evil ways. Normally, such a story would show the allegedly morally superior Athenians prospering and triumphant over their opponents. The very fact that both military protagonists were destroyed, though not necessarily at the same time, would seem to be at odds with the idea of it being a morality tale and instead adds to the credibility of Plato’s narrative as containing some historical truth. Bernard Suzanne offers a totally different interpretation based on the background and motives of Critias(a). Serbian Atlantis sceptic, Slobodan Dušanic (1939-2012), has noted(b) that “while the Atlantis myth has been recognised, with good reason, by the majority of modern Platonists as a parable, no consensus has been reached on the parable’s character or precise purpose.” I’m not sure if this is a criticism of Plato or of modern scholarship!
Plato’s description of the demise of Atlantis and the obliteration of Athens has prompted many writers to link these occurrences with more global events. The association of Atlantis with catastrophism has persisted for over a century, ever since Ignatius Donnelly published his landmark book Atlantis and his contribution to catastrophist literature Raganorak. However, the idea of Atlantis as a victim of a global or at least a very widespread catastrophe was articulated as early as 1788 by Giovanni Rinaldo Carli who claimed that a close encounter with a comet caused worldwide devastation that included the permanent inundation of Atlantis.
In more recent times, commentators such as Stuart L. Harris have specified the cause of Atlantis’ destruction as an encounter with Nibiru (Marduk) in 9577 BC, in a number of papers (c)(d)(e) on the Academia.edu website. If the demise of the Athenian army was concurrent with that of the Atlanteans, 9577 BC is far too early, as Athens does not emerge as a structured society many thousands of years later. However, Harris’ early date is close to the that of the Younger Dryas and the extraterrestrial encounter that bombarded North America, which has been highlighted by Richard Firestone and others.
Atlantis is recorded by Plato as being destroyed in ‘a day and a night’, which led George H. Cooper to made the point that the knowledge of the speed of its demise could only have come from ‘survivors or passing mariners’ and should have been incorporated into the traditions of many nations[236.283].
*What is clear, is that Plato identifies an earthquake as the primary cause of Atlantis’ destruction. If that earthquake was triggered by a very close encounter with the likes of Carli’s comet, it would needed to have come near enough to the Earth and been so highly visible as to demand its inclusion in the destruction narrative!*
The bottom line is that the date of the destruction of Atlantis and its army is not known, although it has been assumed by commentators to have occurred shortly after the war with Atlantis. All that Plato says is that it happened “at a later time’ Similarly, However, Plato records the destruction of the two armies in the same passage (Tim.25d-e) in a manner that might suggest a common cause, a view that I’m inclined to accept.
Catastrophism today is the name given to a school of thought that supports the idea that the history of the Earth has been punctuated by natural events such as floods, fires and asteroid strikes that have caused widespread if not global devastation and that some of these events occurred within the memory of man and are recorded in worldwide mythologies.
Georges Cuvier (1768-1832) is sometimes referred to as ‘the father of paleontology’ and an early exponent of catastrophism.
Worryingly, it is now more generally accepted that further catastrophes will occur as a result of future cometary/asteroidal strikes. One such close encounter, around 2800 BC, was considered by the Christian catastrophist, Donald W. Patten, to have generated the Deluge of Noah(j) and was the source of the flood legends found around the world! Patten nominates Mars as the intruder(l), an idea also advocated by Elsar Orkan, who, however, proposes a date of around 8000 BC for this encounter.
Some readers may think that the subject has no direct connection with Plato’s Atlantis, however, his text refers to a number of catastrophic events that clearly brought devastation to Athens, Atlantis and beyond. The Flood of Deucalion and earlier inundations, Phaeton and other cosmic encounters, plus conflagrations and earthquakes all point to periods of great instability in the early prehistory of the Aegean region and quite probably much further afield.
Jürgen Spanuth devotes chapter 4 of his Atlantis of the North to an examination of “the natural catastrophes of the 13th century BC” that deals with Phaeton and the blizzard of floods, earthquakes and eruptions that beset the Eastern Mediterranean at the end of the 2nd millennium BC. Some of these matters have been recently expanded upon by Nur & Cline(f)(g) and endorsed by Stavros Papamarinopoulos[0750.73].
August 2013 saw studies published(h) which pointed the finger at climate change as the cause of the widespread political instability in that region during the second millennium BC.
Claude Schaeffer, a celebrated French archaeologist, declared in 1948 that on at least five occasions during the Bronze Age the Middle East had been subjected to widespread catastrophic destruction as a result of natural events rather than human activity.
Immanuel Velikovsky is arguably the best know of the 20th century catastrophists, who published two books in the 1950’s that provoked widespread controversy that continues today. There is an interesting albeit a sceptical review of catastrophism in the last century by Patrick Moore & Bob Forrest in Chapter 14 of More Things in Heaven and Earth.(k)
In 1964, the Belgian mathematician René Gallant (1908-1985) published Bombarded Earth which dealt in great detail with the consequences of meteorite impacts with the earth. Gallant, perhaps because of his amateur status as a geologist, never received the attention he deserved.
More recently Allan & Delair produced another book that identified 9500 BC as the date of a global catastrophe following an encounter with a comet. Their conclusions are at variance with Velikovsky’s, particularly regarding dates. Professor Mike Baillie of Queens University, Belfast is a well-known dendrochronologist who has recently entered the debate with his book, Exodus to Arthur that adds evidence from his discipline to support the theory of cometary or asteroidal impacts with the Earth. Unfortunately his work is confined to the last 4,500 years and so casts no further light on the 9,500 BC date apart from offering support for the possibility of extraterrestrial impacts.
However, Richard Firestone and his co-authors have researched an impact ‘Event’ the occurred 13,000 years ago and caused devastation in North America including the creation of the hundreds of thousands of Carolina Bays and some of the outbursts of Lake Missoula. Like Baillie, they claim that a memory of this event has been preserved in the folktales of many of the North American Indians. This book is a must-read for anyone interested in the latest developments in catastrophist research.
The destruction of Atlantis has been linked to a number of possible catastrophic events including earthquakes, volcanic eruptions, floods and asteroid strikes. Plato’s account cites a flood as the immediate cause of the disappearance of Atlantis. In the 18th century Giovanni Carli was probably the first to link a cometary encounter with the Earth as the cause of Atlantis’ demise. This idea has been supported by numerous writers ever since with Emilio Spedicato being one of its leading exponents today.
There are numerous sites on the Internet relating to catastrophism of which one(a) can be recommended as a good starting point for further study. Andy Blackard has listed(b) events connected with global upheavals around 3200 and 2000 BC. An Australian archaeologist, Peter Jupp, is the creator of the Ancient Destructions website(e) which deals with a number of historical mysteries including, Baalbek and Antarctica.
A more recent book by Robert Argod postulates that many of these historical catastrophes were caused by an irregular series of accelerated tectonic movements, although he does not offer a credible mechanism to explain the triggering of such upheavals. Is it possible that the strikes by or near misses with extraterrestrial objects, proposed by so many, generated the tectonic shifts proposed by Argod?
Professor Trevor Palmer has written a comprehensive history of catastrophes and catastrophism from the earliest times and its relevance today. His Perilous Planet Earth includes a couple of chapters in which he reviews Atlantis theories in the context of catastrophism.
Dr Michel-Alain Combes has a PhD in astronomy from the Université Pierre et Marie Curie (Paris VI). He has an extensive website(i) dealing with catastrophism, which translates quite well.
2012 was been promoted as the date of the next worldwide catastrophe based on a highly questionable interpretation of the Mayan calendar. New Age gurus were promising a change in global consciousness, whatever that means. If interested you can read more of this nonsense online(c) or consider a more balanced view(d).
A huge catastrophist bibliography is available online(m)
(i) http://www.astrosurf.com/macombes/index.html (French)
Asteroids, Comets and Meteoroids are all relatively small objects that inhabit our Solar System. When any of them have orbits that intersect with that of the Earth they are known as Near Earth Objects or NEOs. Asteroids (a word coined by William Herschel [1738-1822]) used to be known as minor planets, while meteoroids is the name applied to asteroids that are less than 50 metres in diameter, although some use 10 metres as the classification threshold.
Meteorites have had a history of being considered divine in origin, leading to different levels of veneration in various cultures(v). In the 2nd century, Clement of Alexandria is said to have concluded that “the worship of such stones to have been the first, and earliest idolatry, in the world.”
What is probably the first recorded death from a meteorite strike took place in India in February 2016(z).
Comets, until recently, were generally thought to be composed of just dust and ice, ‘dirty snowballs’, which have orbits that periodically bring them close to the sun at which stage the interaction of the comet’s dust trail with the solar wind produces a highly visible coma or tail. The nucleus can have a diameter of a couple of kilometres.
The chemical composition of comets is now known to be varied and much more complex than previously believed. In 2015, Comet Lovejoy was ejecting the equivalent of “500 bottles of wine every second” when it was closest to the sun, in the form of ethyl alcohol(w). A close encounter with the Earth would have been interesting!
In 1883 a large comet is estimated to have come within a few hundred miles of Earth. It was photographed and some years later the image was hailed as the first image of an UFO!
In recent years comets have come to been seen as potentially more dangerous than asteroids in the event of a collision. This view was graphically demonstrated when the Levy-Shoemaker comet crashed spectacularly into Jupiter in 1994, after breaking up into as many as 21 large pieces before impacting. This comet was originally about 20 km in diameter. However, the distinction between comets and asteroids has been blurred by asteroids sometimes displaying the features of comets, such as asteroid P2013/P5, which in 2013 produced six cometary-like tails.
In 1752, the French astronomer, Pierre-Louis Moreau de Maupertuis, expressed the view that “However dangerous might be the shock of a comet, it might be so slight, that it would only do damage at the part of the Earth where it actually struck” and with coincidental foresight added “ Perhaps we should be very surprised to find that the debris of these masses that we despised were formed of gold and diamonds” considering how Richard Firestone and his associates more recently used the existence of nanodiamonds to confirm the cometary impact of 11,000 BC over North America.
Asteroids and comets have blamed for the demise of Atlantis since the end of the 18th century. It was the Italian polymath, Giovanni Rinaldo Carli, who in 1788 declared that part of a passing comet hit the Earth and was responsible for the destruction of Atlantis. A century later in his second book on Atlantis, Ignatius Donnelly similarly claimed that a comet’s collision was the cause of Atlantis’ destruction. Comets rather than asteroids were initially blamed because of their high visibility. However, as our technology advanced and we gradually became aware of the number of large asteroids that intersect with the Earth’s orbit they replaced comets as the more likely cause of historical impacts.
The early part of the 20th century saw the eccentric William Comyns Beaumontand the mysterious Hans Schlindler Bellamy both supporting the idea of Atlantis being destroyed by an encounter with an extraterrestrial object. The theory has been adopted by a growing number of popular modern writers such as Otto Muck, Egerton Sykes, Andrew Collins, Paul Dunbavin, Karl Jürgen Hepke(a), Frank Joseph explains[102.108] how a number of scholars encouraged by Muck, came forward to publicly state their belief that Atlantis had been destroyed by an extraterrestrial impact or impacts: “They included the world’s foremost authority on Halley’s Comet, Dr. M.M. Kamienski, a member of the Polish Academy of Sciences; Professor N. Bonev, one of the 20th century’s leading astronomers at the University of Sofia, in Bulgaria; and Jack Hills, of the prestigious Los Alamos National Laboratory”.
Emilio Spedicato of the University of Bergamo has written(b) and lectured widely on his hypothesis that the last Ice Age was started by an extraterrestrial impact over a continent and ended with a similar event over an ocean. This second impact was the cause of Atlantis’ destruction and Spedicato specifies Hispaniola as containing the location of its capital.
Spedicato is not alone in believing that impacts by large objects have been responsible for the triggering of past Ice Ages. As we have seen a large number of writers have suggested an impact with the Earth as the primary or at least the secondary cause of the destruction of Atlantis(d). These cosmic collisions have occurred throughout the history of our planet, continuing to this day. Most of the impact material is small and burns up in the atmosphere. Some low-density objects have penetrated the atmosphere, but disintegrated before actually impacting, generating powerful shock waves commensurate with their size. Such an event was the well know Tunguska(i)explosion over that area of Siberia in 1908.
Commenting on the Tunguska event Stephen E. Franklin added that “Less than five hours after the Tunguska object exploded at 7:14 AM local time in Siberia, another fireball was seen over Kagarlyk near Kiev in what is now Ukraine (then part of the Russian Empire) at around 7:00 AM local time followed by the impact of a 1.912 kg stony meteorite.”(ad)
Two similar explosions occurred over South America in the 1930’s. However, some are large enough to survive the journey to the surface. Depending on the size, density, speed and angle of approach, the consequences of a large impact are difficult for the average person to appreciate. As Austen Atkinson wrote “A single impact by a rock the size of (London’s) Millennium Dome could devastate the surface of the globe with an explosive release of energy five times more powerful than the entire world’s nuclear arsenal. On 19 May 1996, just such an object came within 280,000 miles of Earth: six hours from collision. Humankind could have been eradicated.”
The most famous impact is probably that which in the Yucatan took place 66 million years ago and wiped out the dinosaurs. A recent (2019) paper(ae) reports that “excavations in North Dakota reveal fossils of fish and trees that were blasted with rocky, glassy fragments that fell from the sky. The deposits show evidence also of having been swamped with water – the consequence of the colossal sea surge that was generated by the impact.”
11 million years later another impact in the Atlantic is credited with the expansion of the mammals according to a new study by co-author, Dennis Kent from Rutgers University.
An online calculator of impact effects was developed by scientists at Purdue University and Imperial College, London was first published in 2004 and recently updated(g).
By 2009 175 large impact craters have been discovered all over our planet, many more are undiscovered having been destroyed over time by wind and water erosion or hidden by vegetation. In 2006, a crater with a diameter of 30 km was discovered in the Southern Egyptian desert. This discovery may solve a mystery in the same region that has baffled science for over seventy years, namely, the Libyan desert glass that covers an area 60 x 100 km. However, the largest known impact crater is the Vredefort crater in South Africa with a diameter of 300 km (186 miles). But this may have to take second place to the 300 mile wide crater identified in Hudson Bay in North America.
The spectacular collision of Comet Shoemaker-Levy with Jupiter in July 1994 and the manner in which it disintegrated into a number of huge pieces before impacting over seven days, may offer one possible explanation for the mechanism that could produce the apparent clustering of 3rd millennium BC impacts on Earth.
The current estimate is that there are more than 2,000 asteroids exceeding a kilometre in size together with 10,000 over half a kilometre plus millions of smaller items in Earth-crossing orbits; collectively known as ‘Apollo objects‘. The meteor that exploded over central Russia in February 2013 belonged to this Apollo group. Add to this the risk from comets, normally larger than asteroids, and it is obvious that large-scale impacts are inevitable, however infrequent. The good news is that in 2011 it was reported that a NASA space telescope recorded a 40% reduction in their earlier calculation(j) which should be compared with the assessment referred to(f) at the end of the last paragraph of this entry. May 2012 saw further estimates being published(l).
Terminology, definitions and number estimates are constantly changing. Asteroids that are in excess of 100m across with orbits that that come within 7.5 million km of Earth are now referred to as PHAs (Potentially Hazardous Asteroids). As of June 2014 the IAU has listed 1,466 PHAs, while NASA estimates put the actual total in excess of 4,700(q).
As recently as 1953 an asteroid impact with the Moon was photographed as a flash and only in 2002 was the resulting 2Km- wide crater identified. The estimated energy released by this 300 metre wide object on impact would have been half a Megaton of TNT (35 times the Hiroshima bomb). A hit of this magnitude on Earth could have wiped out a large city.
It must be kept in mind that the immediate damage caused by actual impact itself is only the beginning of the story; tsunamis, volcanic eruptions, earthquakes together with worldwide long-term dust veils could trigger climate change leading to ongoing adverse effects on vegetation and animal life. For humans this meant death, destruction, floods, repeated crop failures and probably a breakdown in any existing civil order.
It was as recent as the 1930’s that geologists were being told that Meteor Crater in the Arizona desert was the only known evidence that an impact, with worldwide consequences, had ever taken place. It was also in the 1930’s that the first of the Apollo objects were identified. Since then, the number of large identifiable impact craters grew to hundreds and the number of Apollo objects, whose impact would have global implications, became thousands. It then became obvious that the Earth as we know it is at serious risk. World authorities are slowly realising that the probability of similar impacts in the future are simply inevitable.
Until recently, statistical analysis indicates a major impact every 10,000 years; with the last such event occurred 12,000 years ago possibly destroying Atlantis, directly or indirectly. However, in 2006, this estimate was revised downward to a major collision every 1,000 years with the last impact having taken place around 2800 BC, in the Indian Ocean, where an 18-mile diameter crater has been discovered at a depth of 12,500 feet.
However, a paper(x) published in October 2015 has suggested that a study of mass extinctions over the past 260 million year appear to have taken place every 26 million years coinciding with major asteroid/comet impacts.
So far 175 large impact craters(e) have been discovered all over our planet, many more are undiscovered having been destroyed over time by wind and water erosion or hidden by vegetation. In 2006, a crater with a diameter of 30km was discovered in the southern Egyptian desert. This discovery may solve a mystery in the same region that has baffled science for over seventy years, namely, the Libyan desert glass that covers an area 60 x 100 km. However, the largest known impact crater is the Vredefort crater n South Africa with a diameter of 300km (186 miles). But this may have to take second place to the 300 mile wide crater identified in Hudson Bay in North America. A 2015 report tells of two impact zones that total more than 400 kilometres across, which were identified in the Warburton Basin in Central Australia(t).
Although it appears that similar suggestions have been made since the 1950’s, the debate has now reached a new level. The Hudson Bay feature has generated even greater interest since Richard Firestone, a nuclear physicist together with Allen West and Simon Warwick-Smith published their claim that it was created around 11000 BC and had human witnesses who preserved their memory of it in their local folklore and that may have been responsible for the extermination of the Clovis people. Firestone’s tentative 11000 BC date for this event is earlier than Plato’s even more questionable 9600 BC date for the destruction of Atlantis might be connected since the event described by Firestone & Co. would have had global consequences and could have effected any suggested Atlantis location. In 2007, at a news conference during Joint Assembly of the American Geophysical Union, in Acapulco, Mexico, two archaeologists from the University of Oregon, Douglas J. Kennett and Jon M. Erlandson added geological evidence to support to Firestone’s thesis. In 2008 evidence of an exploding comet/asteroid over Canada during the same period was presented(c) by other academics from the University of Cincinnati. However, it must be noted that the Firestone hypothesis has encountered some criticism since the start of 2009 and must therefore be treated with due caution. This criticism appears to be gaining support according to a May 2011 report(h). In June 2012, James Kennett, son of Douglas Kennet mentioned above, was part of a team who announced further evidence of a major impact event 13,000 years ago extending from Pennsylvania and South Carolina as far as Syria(m).
Dr Reinoud de Jonge has written a number of articles(d) that drew on petroglyphs in Brittany to support his contention that the Earth had an encounter with a cometary body in 2345 BC. This would appear to complement the work of Mike Baillie and George Dodwell, who echoed William Whiston’s proposed date of 2346 BC, for an encounter with a comet that caused the biblical Deluge.
Since only 30% of our globe is exposed land, it is reasonable to conclude that 70% of impacts will have hit water, leaving little lasting evidence. However, at least ten of these identified impact craters occurred after the last Ice Age and at least seven of which date from around the third millennium BC, at period when there were widespread cultural collapses.
In a recent book the renowned dendrochronologist, Mike Baillie, has outlined compelling evidence from his own discipline combined with ancient mythologies to support the idea of extraterrestrial impacts in early historical times. May I suggest that the mythologies that possibly relate to multiple impacts are in fact recollections of a comet that had been visible for some time before breaking up under the gravitational influence of our planet prior to impact? This idea was developed by Baillie in a subsequent book written with Patrick McCafferty that focused on Celtic mythological figures. Comets rather than asteroids are more likely to have contributed to the development of myths since an asteroid would not have been visible long enough for it to develop an identity that would be remembered in legend. Graham Phillips has gone further and proposed that a close encounter with a comet in the middle of the 2nd millennium BC triggered the development of monotheism at that time. Furthermore, he contends that as the Earth passed through this comet’s tail, it introduced large quantities of an amino acid, vasopressin that heightened aggression in humans leading to large scale conflicts worldwide. This comet, 12P/Pons-Brooks is due for another close encounter with Earth in 2024.
A 2012 paper(o) by Fernando Coimbra investigates the influence of unusual astronomical events, in particular comets, on the subject matter of rock art. An earlier paper(p) by Coimbra looks at the swastika as a specific example of a reflection of such an event.
Mythologies, worldwide, offer evidence of these impacts and have been subsequently reinforced by classical writers who describe in non-scientific terms the effects of these extraterrestrial assaults. Pliny wrote in his Natural History (Book II, sec 91) of ‘A terrible comet was seen by the people of Ethiopia and Egypt, to which Typhon, the king of that period, gave his name; it had a fiery appearance and was twisted like a coil, and it was very grim to behold: it was not really a star so much as what might be called a ball of fire.’
Similarly the Greek myth of Phaëton has been interpreted as a record of an encounter with a comet. Edith and Alexander Tollmann also identified an 11,000 BC impact with the Köfels region of the Austrian Tyrol as one of the impact zones. The interpretation of ancient legends and myths is obviously a matter of subjective response, but the volume of such evidence is so great that the probability of a number of major impacts being within the memory of man, who relayed the experience down to us through the medium of tradition, is quite high.
The fact that our Earth is continually at risk of a cosmic collision, the physical evidence of recent and past collisions, the recording of impacts on the Moon and Jupiter compounded with stories in ancient mythologies offer strong grounds for accepting the possibility of Atlantis being destroyed as a result of a collision with an extraterrestrial object as a credible working hypothesis.
While an asteroid impact causing the destruction of Atlantis is relatively easy to accept, some authors have proposed even more dramatic scenarios where the impact was so great that it caused the Poles to change position and/or the Earth’s outer mantle to move relative to the inner core. There is little doubt that cosmic collisions of all the possible natural catastrophes pose the greatest possible threat to life on earth. There is an interesting website(c) that discusses both catastrophes and Atlantis. Another site(e) has a small collection of images of impact craters as seen from space. 2010 produced a frightening upward reassessment of the asteroid threat(f).
In 2001 NASA(k) identified 1,000 asteroids and comets orbiting close to Earth that are capable of causing catastrophic damage to our planet in the event of a collision. An interesting map was published(n) in February 2013 showing the locations of 34,513 impacts dating back to 2300 BC.
Recent deliberate encounters with comets and asteroids have produced images and data that have raised questions about the traditional description of comets being composed of ice and rock. The lines between asteroids and comets are becoming increasingly blurred and new definitions required(r). The trend now is to see asteroids and comets as part of a continuum. Evidence is emerging that the H20 previously associated with comets may have been OH radicals(s).
The 2014 landing on Comet 67P/Churyumov-Gerasimenko would appear to have destroyed the ‘dirty snowball’ description of comets, coined in 1950 by the noted astronomer, Fred Whipple, and should now be abandoned.
Although large asteroids or comets have caused and will again cause global catastrophes on a scale that we can only imagine, they are not the greatest potential threat to our existence. It is estimated that our galaxy, as in others, are also home to free-floating giant gas planets untethered to any star, which, if they wandered our way, could not only obliterate our planet but de-stabilise our solar system.(u)
Terry Westerman offers a fascinating overview of possible global impact sites on his fully illustrated website(y).
Fortunately, the death and destruction caused by comets is balanced by the probability that they are also the source of life on our planet. This idea is gaining greater acceptance with a further paper(aa) offering additional supportive evidence published in April 2016.
Nevertheless, improved vigilance is required if we are to believe Peter Brown of the University of Western Ontario, whose research in 2014 concluded(ab) that hazardous asteroids are 10 times more likely to hit Earth than previously thought!
(q) BBC Focus Magazine, July 2014, page 67.
*(r) http://www.thunderbolts.info/forum/phpBB3/viewtopic.php?f=3&t=15318 (Link broken Oct. 2019)
(s) http://www.thunderbolts.info/forum/phpBB3/viewtopic.php?f=3&t=15226 (Link broken Oct. 2019)*
The Deglaciation that occurred at the end of the last Ice Age has attracted a lot of attention from Atlantis seekers because it coincides with Plato’s apparent date for the destruction of Atlantis and provides us with a possible source of the flood that subsequently not only wiped out the Atlanteans but possibly also the Athenians. However, meltwater from deglaciation causes global sea levels to rise very, very, slowly and so is extremely unlikely to have caused the destruction of the Atlanteans or Athenians as described by Plato.
The melting of the ice caps gradually caused the ocean levels to rise over a period of thousands of years and at times the retreat of the glaciers was halted and occasionally reversed. Although the melting of the ice was relatively steady, the water produced did not always reach the sea in a steady flow. Instead, it was frequently punctuated by enormous discharges of water particularly where ice dams had retained vast melt water lakes.
In the 1920’s a maverick geologist, J. Harlen Bretz (1882-1981), postulated that a huge ice-age flood had carved the landscape of Eastern Washington state, in just a few days. In spite of acrimonious opposition from the geology establishment of the day, Bretz persevered with his investigations, which eventually led to the identification of Lake Missoula as the probable culprit. Bretz was finally vindicated in 1979 when, in his nineties, he was awarded the prestigious Penrose Medal for his work(f). There is a beautifully illustrated National Geographic online article that reviews Bretz’s work(i).
These discharges of huge quantities of water are recognisable as relatively sudden spikes in the rate of sea level increases and are referred to as Melt Water Pulses WMP).
Lake Missoula in what is today the state of Montana is one of the best studied of these glacial lakes. The regular discharges from Lake Missoula, following ice dam collapses, were responsible for the creation of the dramatic scablands of the North-Western United States. Studies have revealed that between forty and eighty such floods were released from Lake Missoula alone.
However, an alternative to Lake Missoula as the cause of the scablands has been recently proposed(g), namely, the younger-dryas comet impact event. This event was highlighted by Richard Firestone and his colleagues in The Cycle of Cosmic Catastrophes. My problem with the idea of the comet impact is that it was a single event, whereas the Missoula discharges were numerous.
The power of fast flowing water was recently highlighted by a report published(c) in the journal of America’s National Academy of Sciences, where a study of Iceland’s unpronounceable Jokulsargljufur canyon indicated that this huge feature was created in a matter of days. In Iceland, such glacial outburst floods are known as Jökulhlaups(d).
It has now been estimated by scientists that around 6200 BC the ancient glacial Lakes Agassiz and Ojibway discharged into the Atlantic Ocean. These lakes were more than twice the size of the Caspian Sea and on their own are estimated to have raised sea levels by up to 4 feet. The freshwater flow is calculated at between 25 and 50 times the flow of the Amazon River and recent studies suggest that this sudden inflow of fresh water brought the Gulf Stream to a halt for more than a hundred years. A 2016 report(e) from CAGE (Center for Arctic Gas Hydrate, Climate and Environment) suggests that the Gulf Stream was not interrupted during the Ice Age.
Nick Thom has suggested that an even more dramatic consequence of the discharge from Lake Agassiz was the tilting of the Earth’s axis leading to the biblical Deluge and recorded around the world in hundreds of flood myths!
Similar melt water lakes across Northern Europe retained by ice dams produced equally dramatic discharges as the dams periodically broke. One of these occupied what is now the Baltic Sea and was 30 metres above the then ocean level before bursting into the North Sea around 10,000 BC. Less well known is the flooding that took place further east resulting in the creation of a vast inland sea of which the Black and Caspian Seas were just a small part. Ronnie Gallagher has written a revealing paper on the subject(a).
It is worth noting that, although on a smaller scale, two thirds of the thousands of Himalayan glaciers contain glacial lakes, which because of global warming today are growing at risk of bursting with consequent catastrophic results. As these glaciers retreat, apart from the damage to people and property the discharges will gradually reduce the downstream flow of water to rivers such as the Ganges.
paleoclimatologist, Hartmut Heinrich, who as recently as 1988 published evidence that there had been at least six massive discharges of icebergs from the Laurentide Ice Sheet during the last Ice Age. These discharges could have contained millions of cubic kilometres of ice and must have caused substantial sea level rises. This Laurentide Ice Sheet was an enormous mass of ice that stretched from the Arctic through eastern Canada to the northern half of the United States that covered over 5 million square miles. The weight of this ice sheet was so great that it has been calculated that it depressed the earth’s crust by nearly half a mile. A recent paper contends that it was the collapse of this ice sheet, 8000 years ago causing a sea level rise that led to the breaching of a ridge damming the Bosporus and the inundation of the then freshwater Black Sea, which flooded over 73,000 square km of land.
In the southern hemisphere it was discovered a few years ago (Science, Dec.22, 2000) that the River Amazon had experienced a doubling of its outflow between 9800 BC and 9700 BC, probably as a consequence of the melting of Andean glaciers and perhaps increased rainfall during this period. The dates proposed are very close to the 9600 BC date provided by Plato for the submergence of Atlantis.
All these worldwide discharges must have resulted in the inundation of low-lying landmasses, such as the Celtic Shelf or Sundaland, in fits and starts forcing the inhabitants of these regions to regularly migrate to higher ground.
Since it is reasonable to assume that a large percentage of human settlements were then, as now, located along coasts, particularly at river mouths, the consequence for these embryonic cultures must have been catastrophic. It is very easy to see how legends of sunken civilisations probably have a very sound basis in fact. Two books by Graham Hancock and Stephen Oppenheimer have covered this idea in greater detail, lending credibility to the idea of a sunken island such as Atlantis.
However, it can be reasonably argued that the effects of deglaciation are not what Plato described. He spoke of earthquake and a flood that overwhelmed both the Athenians and the Atlanteans. This would more closely match the aftermath of a large seismic or tectonic event that generated enormous tsunamis rather than the gradual rising of sea levels, which even at its most dramatic could never have produced the effect of sinking Atlantis overnight.
However, the waters of tsunamis eventually flow back to the sea, but Plato’s account describes the event resulting in the creation of muddy shallows. To me it sounds more like liquefaction which occurs in soil with particular characteristics when subjected to an earthquake(b), similar to the destruction of the cities of Canopus and Herakleion near Alexandria.
A website that graphically illustrates the process of deglaciation after the last Ice Age is available(h).
(b) http://www.ce.washington.edu/~liquefaction/html/why/why1.html (offline June 2016) See: https://web.archive.org/web/20160316063736/http://www.ce.washington.edu/~liquefaction/html/why/why1.html