The Last Days of The Earth
A Fear of The Dark and A Denial of The Unknown
A re-introduction to Victor Clube's The Problem of Historical Catastrophism
by gary d. goodwin
There aren't many that like to swim in the open ocean. It's dark and cold - and full of sharks. And even though wandering in the wilderness does indeed appeal to a few, it does remain dangerous. However, these adventurers openly acknowledge the danger and make approriate preparations prior to activities in these areas. Since the beginning of The Millennium Group, we have been concerned about the issue of near earth asteroids and comets. More specifically, that issue is the denial by the status quo at NASA concerning the danger of literally thousands of near earth and earth crossing asteroids and comets. This open ignoring and even documented denial of the obvious has crippled our ability to develope an adequate response to these sure-to-come attackers. We have been robbed as a civilization of the appropriate time to prepare ourselves.
It's incredible how we accept the Wild on earth to be filled with danger, yet even with documented historical experience, we continue to deny the dangers of space. The universe is not just a beautiful expanse above our heads to behold, it is in reality a violent and unforgiving frontier. Everyday brings more discoveries of earth crossing asteroids and comets. Yet these speeding bullets that are zipping past our heads are given less press coverage than the stock market. That surely doesn't come as a shock to anyone, especially to those that read this page with any regularity.
It has been suggested that if the truth were widely known about this looming and impending danger, the stock market wouldn't exist very long anyway. Afterall, who would invest in futures if there wasn't going to be any? The stability of our society may just rest on the denial of percieved chaos and the acceptance of these falsehoods. At least that's what our government would have us believe. We've all been asked, or at least pondered ourselves, what would I do if I knew that I would die tommorrow? Would I go out and spend all of my money, would I take a vacation to Hawaii, or would I try and climb Everest? For myself, I would spend my last days with my family and friends! They are the most important thing to me.
But the reasons for this denial appear pretty obvious. As long as we go to our jobs, work hard, pay our taxes - stay locked into that prime interest rate, the system rolls on. The rich get richer and the poor get poorer. The focus of *their* existence - wealth, control and power is maintained. The working class - the Smiths and Jones' of the world are not a threat. But let me give our benefactors a few threatening words of advice concerning that threat that will even bring them down - a threat that is much more dangerous than myself and this webpage -
There are lions and tigers and bears out there.....
THE PROBLEM OF
OXFORD UNIVERSITY, DEPARTMENT OF PHYSICS, KEEBLE ROAD, OXFORD, UK & ARRNAGH OBSERVATORY, COLLEGE HILL, ARRNAGH, UK
First... A few Introductory Quotes from the following article:
"Thus, by seeking to suppress, ridicule, or eliminate the fear of cosmic disaster (instead of seeking to explain its origin, nature and dynamics), the purveyors of an elitist doctrine [NASA et al] come to be merely the centrally placed advocates of a "modern enlightenment" which prolongs widespread ignorance as to the actual nature of the cosmic and terrestrial environments. Moreover by incorrectly claiming there is nothing to worry about in the sky, these advocates cultivate an intellectual and cultural climate of irrationality...The resulting risk to civilization is nothing short of a scandal."
"The space age evidence for apocalyptic threats has already put limits on the extent to which the principle of uniformitarianism can be admitted. The scholarly issue at stake therefore is nothing less than the survival of civilization in the face of such threats. However there remains a particularly vehement tradition within modern scholarship which not only seeks to eliminate apocalypticism from the course of classical, medieval and modern history but also, as a consequence, seeks to impose a highly distorted view of the cosmic environment upon the untutored public."
"...modern astronomers and historians have been able to construct a largely uneventful history for mankind which is in keeping with the perceived absence of any future trauma . Government and society can take a good deal of comfort from this beguiling scheme, of course, but the disintegration of comets is also an established physical property of these objects  and it has been known for some thirty years that a recent giant comet is necessary to explain the extreme over-abundance of sub-cometary material in inner Solar System space . It is clear that the full implications of comets to society and civilization can no longer be ignored."
"It is easy to understand, therefore, why many astrophysicists were provoked by the writings of Velikovsky [78, 79] who, as a psychoanalyst, was justifiably very interested in the origins of apocalypticism but who unfortunately laid himself open to easy condemnation through his advocacy of an irrelevant and certainly inadequate "planetary" theory for some past comets. Normally, of course, astrophysicists would display some forbearance in the presence of theoretical inadequacies of this kind but, in this case, it was all too obvious that they had failed to address the historical evidence for apocalypticism and were merely intent on creating a cover for their own deficiencies."
It has been shown here that the approximately centennial rise and fall of fireball streaming sometimes associated with Earth-approaching comets or asteroids is also the historical source of apocalyptic "signs". This streaming is a proxy for hazardous swarms of sub-cometary debris representing a higher flux to Earth than normally conceded of bodies in the mass range~10 12 -10 15 g. Largely overlooked since early modern historical time (and even flatly proscribed by some authorities [113, 58]), this hazard appears most commonly to take the form of global climatic recessions, involving high-level dust albeit low-level multi-megaton explosions associated with the most robust debris are by no means excluded. These recessions are a feature of the general flow of "Taurid" material to Earth recorded in polar ice-cores and ocean sediment-cores, now recognized as being responsible for a basic 5000 year doublecycle alternately producing global warming and global cooling. During the course of the Enlightenment, mankind has singularly failed to come to terms with this apparently centennial threat, having become strangely preoccupied during the Space Age with a very much less frequent threat (roughly a thousand times less frequent!) which is directly due to comets and asteroids. Whether or not mankind recognizes the approximately centennial threat is tantamount to choosing between apocalyptic and antiapocalyptic outlooks on the environment. This question as I have shown, is of deep historical and political significance being intimately bound up with the origins of Christian doctrine and with the elitist desire to perpetuate anti-apocalypticism along with its appropriately distorted cosmological setting. In view of the intellectual and cultural climate of irrationality which arises thereby, it is a moot point whether mankind will meet the challenge posed by this question before the next bout of apocalyptic terror descends. Such a situation represents an intolerable risk to civilization.
And Now... The Article:
Astronomers at the dawn of civilisation perceived danger in the sky and society was notably unsettled . Later, astronomers were to perceive order in the cosmos and society was to become notably less unsettled. The perception of danger never entirely disappeared however and there was considerable pressure on astronomers by the elite of society to uphold a model of the celestial environment in which celestial calm was very much the order of the day. This pressure still exists and leads to an elitist doctrine in which the biosphere's supposedly anti-apocalyptic environment is an essential feature of the cosmological setting. The latest version of this doctrine to acquire favour is largely the work of a single, dominant, intellectual influence, namely that of J H Oort  during the central years of the present century when there was a critical break in the general administration of astronomical affairs due to the Second World War. His unavoidable starting point, based upon the most accurate orbital measurements available for comets, was the cometary cloud around the Solar System and its critically valued dynamical isotropy. To preserve this condition against any serious perturbation, thereby avoiding any substantial changes in the near- Earth cometary flux during the course of geological and human history, there had to be very few stars moving slowly past the Sun. This condition was readily upheld if the primary (or mainstream) circulation of the Galactic disk was much the same as the observed (or so called "standard") motion of spiral arm material in the solar v aconite. Oort essentially preserved the required condition therefore by ignoring two prominent asymmetries known to be present in the large-scale motion of the disk. The first of these asymmetries, orthogonal to the Solar Galactocentric axis, meant disregarding a set of potentially very serious perturbations of the cometary cloud that would arise with a more probable mainstream circulation which included the Sun. The second of these asymmetries, along the Solar Galactocentric axis, meant disregarding a potentially gross hubble parameter within the Galaxy in absolute conflict with the standard cosmological redshift. These deliberate evasions, never justified at the time nor since, have become the established basis of a highly distorted cosmic environment which is now systematically imposed upon the untutored public by uninformed specialists and commentators with a view to upholding the long-established anti-apocalyptic tradition. However these evasions are no longer valid since a substantial population of nearby slow moving stars has been detected by the Hipparcos Astrometry Satellite and distant galaxies having purely cosmological redshifts evidently reveal gross concentrations of the hubble parameter (known as "quanta") in the vicinity of the intervening galaxies. By explaining rather than evading the prominent asymmetries therefore, the motion of the local spiral arm and the mainstream circulation of the disk are now clearly distinguished and it becomes more probable that successive, centrally injected, "grand design" spirals which condense into dark (or sub-stellar) bodies and undergo dynamical friction through the disk are intermittently replenishing the mainstream circulation. It follows in accordance with the geological and historical records that the cometary cloud perturbations giving rise to the near-Earth cometary flux are modulated by a vertical oscillation of the Sun which is predominantly under the influence of a "dark matter" mainstream circulation of the disk. It turns out in effect that the biosphere's anti-apocalyptic environment can no longer be preserved. Thus, by seeking to suppress ridicule or eliminate the fear of cosmic disaster (instead of seeking to explain its origin, nature and dynamics), the purveyors of an elitist doctrine come to be merely the centrally placed advocates of a "modern enlightenment" which prolongs widespread ignorance as to the actual nature of the cosmic and terrestrial environments. Moreover by incorrectly claiming there is nothing to worry about in the sky, these advocates cultivate an intellectual and cultural climate of irrationality in which the socially most damaging versions of apocalypticism and anti-apocalypticism (e.g. fundamentalism and millenarianism), those involving an appeal to mystical, incorporeal or spiritual influences in Nature, continue to flourish. The resulting risk to civilization is nothing short of a scandal.
1. THE ANTI-APOCALYPTIC
The space age evidence for apocalyptic threats has already put limits on the extent to which the principle of uniformitarianism can be admitted. The scholarly issue at stake therefore is nothing less than the survival of civilization in the face of such threats. However there remains a particularly vehement tradition within modern scholarship which not only seeks to eliminate apocalypticism from the course of classical, medieval and modern history but also, as a consequence, seeks to impose a highly distorted view of the cosmic environment upon the untutored public. This tradition, to do with comets, is only less vehement amongst the public at large on account of a general presumption, based on historical precedent, that the anti-apocalyptic tradition will nevertheless prevail. A 'scholarly' tradition under these circumstances which again ceases to prevail can only be regarded as a 'scholastic' tradition in due course. On the other hand, the public greatly values the freedoms which have come with the achievements of science and the current anti-apocalyptic tradition, in keeping with uniformitarianism, has been an increasingly established feature of science since its seventeenth century inception under the auspices of the Royal Society in England . This ultimately means that our understanding of planets, stars and galaxies has broadly developed during the past three centuries without any reference to apocalypticism and that the public does not therefore fully appreciate the significance of comets. The reason for this distortion was better understood during the early stages of enlightenment when the anti-apocalyptic tradition was more clearly perceived as a matter of political expediency. Even the Society's most hallowed president Newton, for example, could only preserve his scientific reputation by publishing a posthumous apocalyptic tract . The point here is that a revived anti-apocalyptic tradition did then prevail and was as much an imperial issue as a scholarly one, connecting the aspirations of an emergent Anglo-Saxon Enlightenment with those of Papist Rome and Hellenistic Greece. The tradition indeed can be traced back at least two millennia to Alexandria, the main Near-Eastern conduit through which the recorded knowledge of past apocalypticism first reached the West, and to a then highly distorted (i.e. Aristotelian/ Ptolemaic) view of the cosmic environment which eventually needed all the powers of a medieval witchhunt and Inquisition to keep in place. In short, the history of Western civilization points to a continuous tradition of anti-apocalypticism and distorted cosmology whose advocates do become irrepressibly savage from time to time. This vehemence, it is clear, marks a ready determination on the part of bourgeois society to quell apocalypticism whenever it takes root. This mostly happens not only on account of the successive revelations which cause cosmic catastrophe to be anticipated (as the original Greek word implies) but also on account of the highly degenerate condition into which society is then commonly plunged as a result of its increasingly abject state of terror. But while it is perhaps easy to understand that bourgeois society might seek to impose a distorted view of the cosmic environment for the purposes of avoiding a degenerate condition of society whenever apocalypticism emerges, it is not so obvious in modern times that mankind can afford to allow such distortions to be introduced when there is a practical need to judge what should be done about the future state of the cosmic environment. It would appear that there is a particularly vehement tradition within modern scholarship which is no longer required! The Greeks in fact were principally concerned to adapt eastern knowledge to the needs of empire and were the first to press for an essentially teleological account of apocalypticism which also carried the assurance of ecumenical (i.e. Christian) rather than nationalistic (i.e. Judaic) salvation. This priority is perhaps less certain nowadays since similar ecumenical principles were developed by the Zoroastrians  and the Greeks may have borrowed their ideas from another nation with imperial ambitions (the Persians). One way or another, the Greeks (i.e. the gnostics) ultimately took over a 2500 year old apocalyptic record originating from Chaldea and critically introduced incorporeal (i.e. spiritual) elements to what would otherwise have been a purely corporeal (i.e. material) account of the cosmos. These ingredients would eventually imply a tradition of anti-apocalypticism and distorted cosmology founded upon a supposedly partisan, or "providential", divinity. This "deus ex machina" ultimately served no deeper purpose than a lucky mascot or guardian angel but as a pervasive influence folded into the most obscure workings of the observable cosmos (see gnostic cosmology in particular ), the reassurance on offer through such sophistry evidently went beyond the everyday reach of bar-room critics and provided an inherently stronger social glue in times of urgent cosmological debate (note the acceptance of Christian cosmology in particular by the Roman administration). As such, the tradition would survive since it appeared to counter the otherwise terminal character of the highly degenerate condition engendered by apocalypse, basically removing core bourgeois societies at the heart of nations and empires from contention. Indeed, such a tradition would understandably be favoured by feudal "ancient regime" societies in the past. For the same reason, it would also be favoured by the narrow elites of academe business, military and government at the heart of democracies today. The space age in other words, like past revelations, was bound to provoke a traditionally vehement response albeit the latter was also bound to be subdued to the extent that a suitably distorted cosmology remained adequately entrenched. Historically of course these periods of complete breakdown in society, often involving extreme hedonistic tendencies are also characterized by extreme anti-apocalyptic tendencies e.g. millenarianism. When these conditions arise, in the absence of a strong grip on reality, perfunctory government is often given to placing a wildly optimistic slant on the future state of the environment. Wise government on the other hand, retaining a strong grip on reality, does not reject apocalypticism per se. All the same, such government in the past has frequently resorted to the likes of prayer, sacrifice and moral exhortation in the presence of apocalyptic threats apparently in the vain teleological belief such actions may have some direct influence on the supposed powers that give rise to cosmic catastrophe. Nowadays though, as long as teleology is expunged from science, the perceived obligation on hard-headed government is more to take such practical measures as are within its scope both to avert such catastrophe and to mitigate its effects. The main requirements evidently are (a) a proper understanding of the apocalyptic process, past and future; (b) a proper acknowledgment of its utter pertinence; and (c) such preparations as are essential to face up to the likely form future apocalypticism will take. Stages (b) and (c) are of course still barely with us at the present time and the dual purpose of this presentation, with (a) particularly in mind, is (i) to focus upon the perceived problem of cosmic catastrophism during the past 2000 years, and (ii) to outline its most probable explication in terms of the latest giant comet from "deep space" to penetrate and settle in the inner Solar System (i.e. our understanding of the world around us (and our reaction to it) is limited to a greater or lesser extent by certain conventions and paradigms which may, for example, cause us to downgrade historical facts at the expense of scientific facts, or vice versa, to the potential detriment of society generally. The modern tendency in fact is to write apocalypticism out of cosmology altogether with the result that neither government nor society has much awareness of the history of interaction between our planet and the cosmic environment. Indeed it is no longer widely appreciated that apocalypticism has always been the paramount perception since the dawn of civili-zation (i.e. since cuneiform records began) and that, while the Roman Catholic Church (in line with gnostic teaching generally) sought to impose an anti-apocalyptic outlook from about the second century AD onwards, its successful imposition was only spasmodic and not finally achieved until the European Enlightenment ca 1650-1850 AD. As it happens, it was during this period that the balance of opinion in favour of apocalypticism rather than anti-apocalypticism was finally reversed. Thus we now recognise three critical interludes of revived apocalypticism and extreme social upheaval during the course of modern global history (ca 1650, ca 1790, ca 1850) when those who would emerge to fashion the antiapocalyptic environment and its cosmological setting would find it necessary to invoke a material cosmos and yet keep mystical, incorporeal or spiritual influences in place. The fundamental empirical fact to be recognized here nevertheless is a disintegration and collapse of society as a result of celestial traumatization which has been a seriously recurring problem throughout the course of history . The traumatization commonly involves a perception that the "last days" are at hand or that the "end of the world" is coming. The association of this problem with prophecy based on revelation is of course well known . However, in so far as the relevant astronomical knowledge is usually limited to a very small group of experts with< relatively little historical knowledge, and vice versa, there has been and still is a very strong tendency to associate such prophecy more or less exclusively with comets . This unfortunately results in a grossly simplified perception as to the general nature of revelation, causing the whole issue to become hopelessly clouded and seriously misunderstood in modern times. Thus despite the major technological advances which have taken place during the course of the twentieth century, it can hardly be said that civilization is any the less at risk on account of the apocalyptic process.
3. THE INTERRUPTION OF HISTORY BY
Fear to the point of absolute terror as a consequence of revelation, then, has been a feature of certain periods during the course of history when, as a result of specific observed phenomena in the sky, it was accepted that a cosmic catastrophe was imminent. Although these occasions did not necessarily materialize locally in the form that was ultimately feared, this was evidently not regarded as a serious reflection on the quality of the prediction since a longer term regularity in cosmic affairs was also widely perceived which meant that society as a whole would undoubtedly experience a calamitous cosmic bombardment at some stage in the possibly not so distant future. Thus historians of the Christian era whose ideas can now be traced back through Hellenism and Judaism to as early a source as Zoroaster during the second millennium BC , for example would clearly characterize history by a sequence of lesser upheavals at intervals of a few centuries and by more serious upheavals at longer intervals of one or several millennia. This "millennial" perspective on the historical continuum was of course to be further modified in the hands of teleologically minded anti-apocalypticists who, as "millenarians", would be inclined to see their time or that following the next upheaval as a final, divinely ordained millennium. This overall perception of the physical environment has in fact been deeply ingrained in the general consciousness of Western civilization and has substantially weakened only during the course of the nineteenth and twentieth centuries AD. It does not follow of course that the past perception is therefore necessarily correct but no more is our present point of view validated by ignoring the past perception. In accordance with this overall perception the underlying or essential reality of the evidently terrifying process described in the Christian Book of Revelation was never seriously in doubt. However the precise sequence of events relating to the successive upheavals has undergone several modifications during the course of history, no doubt reflecting the difficulty our ancestors had in determining the precise celestial process. One notes for example that the Book of Revelation is a product of the latter half of the first century AD being the accepted Christianized version of the previously existing Jewish Book of Daniel. The latter was originally composed during the Babylonian exile in the sixth century BC and underwent considerable revision during the Antiochan persecution in the second century BC before its adoption by the Christian movement at the turn of the millennium. This recurring interest in apocalypse evidently corresponds to new periods of revelation and a quickening sense of foreboding throughout the civilized nations of the Near East and the Mediterranean  which was eventually perceived as reaching some kind of nadir  during a new and rather serious period of revelation coupled with the fifth century decline and fall of the Roman Empire . This period of revelation appeared sufficiently serious for a time thereafter to be taken to mark the start of a new world calendar (i.e. with 0 AM I = 500 AD), but the turn of events marking the subsequently perceived relationship between Rome's successor civilization in the West and its cosmic environment, after considerable dispute and a father "false start" (i.e. with 0 AM II = 600 AD), was not officially resolved until the adoption of the Christian calendar in 800 AD, supposedly with the ultimate Christian millennium by then well advanced . Even then the pattern of events remained uncertain and with the arrival of further significant periods of revelation during the eleventh and fifteenth centuries AD, the pace of expectation quickened remarkably during the sixteenth and seventeenth centuries with increasingly serious attempts to establish when the final cosmic bombardment was due [76, 5O, 37]. These efforts culminated with the supposedly definitive studies of revelation by Newton  only to be more or less immediately abandoned by the whiggish ascendancy in England; then by its counterparts in Anglo-Saxon America at the end of the eighteenth century AD and in the rest of Europe towards the middle of the nineteenth century AD (see Section 6 below). By this time, there was widespread appreciation of the fact that each period of revelation provoked a revival of historical knowledge and future prognostication based upon the records of earlier revelations. Thus the Book of Daniel took its lead in many respects from the Book of Jubilees, often attributed to Moses, and from the even earlier First Book of Enoch attributed to a patriarch around the beginning of the second millennium BC . It follows that the Book of Revelation was widely seen as preparing the way for a major celestial bombardment some time beyond 100 AD in accordance with a past experience which involved both a significant revelation and a global catastrophe during the third millennium BC and a series of lesser revelations since which was chronicled by the Jewish Old Testament (covering some 2000-2500 years in modest detail) and the Christian New Testament (covering the subsequent 50 years in great detail). As it turned out, Christians were not the only ones by the fifth century AD to be convinced of an impending catastrophe and of the need to prepare for the final millennium . Thus it was during this period and its lengthy aftermath that successive waves of invaders (barbarians and Vikings) penetrated the Roman Empire and settled in the so-called "deserted lands". These arose under conditions that were evidently alarming enough to be perceived as indicating the arrival of the forthcoming millennium . These invaders, as often as not, were confronted only by an imperial administration whose appeal to Christian principle meant turning a blind eye to powerful squatters. By such means the Holy Roman Empire emerged, making up a patchwork of territories under the control of aristocracies naturally inclined to cooperate in the application of Christian principles. It has to be appreciated of course that while the ancient testaments provided a record of dramatic historical events (including revelations) by way of illustrating how the long interaction between cosmos and mankind affected a particular people, the main contemporary purpose of the testaments was to achieve a standard of social behaviour throughout Western Europe in the continued presence of such events that not only matched the intentions of a supposed cosmic authority but sustained the pre-eminence of an original Roman administration by appealing to its corresponding human authority and to its apostolic succession. It is reasonable to suppose these more secular aspects of "Christian policy" would have been of at least as much significance as the perceived teleological aspects of revelation. Thus the Holy Roman Empire to be originally moulded in association with "barbarian" aristocrats by 800 AD was to be penetrated and further moulded in association with "Viking" aristocrats, thereby laying the foundation for a deeply schismatic Christian church in the West whose Protestant and Catholic establishments increasingly polarised around doctrinal issues to do with the nature and purpose of revelations. Indeed there is little reason to doubt that Newton, for example, would have seen himself as but the latest in a long line of European scholars-still essentially within the general ambit of the Holy Roman Empire-who sought to give physical meaning to revelations both before and since the decline and fall of Rome itself (see Section 8). To separate out issues of secular power and teleological catastrophism thus is to do not so much more than Seneca did for the Roman people when he drew upon the knowledge and experience of their Greek and Etruscan neighbours and presented his analysis of the situation around the same time as the author of the Book of Revelation. Seneca's great fame is that of a philosopher and adviser at the very heart of the Roman Empire during its ascendancy. He has been described as one who "disapproved of the world in which he lived [while playing] a leading role in it, as was appropriate for a tough Roman pragmatist" . Whilst addressing the Natural Questions perceived to be of the greatest public significance, starting with "Lights in the Sky", he was to emphasise the two branches of knowledge, moral philosophy and cosmology, which in his opinion evidently mattered most to mankind: "one teaches us what ought to be done on Earth, the other what is done in heaven". It evidently followed that "the mind possesses the full and complete benefit of its human existence only when its spurns all evil, seeks the lofty and the deep, and enters the innermost secrets of Nature". There can be little doubt that the principal focus of Seneca's attention prompting such pronouncements was the longer term regularity (i.e. fixed intervals) that emerged in the observed incidence of a particular celestial phenomenon which corresponded to the unveiling of "advanced announcements of death by the universe". The celestial phenomenon involved is evidently the multiple incidence of "fiery shapes or so-called boards, balls, torches and blazes", various categories of what have later been classified as "blazing stars", "providences" or "fireballs" and which can now only be attributed to the hosts of defunct cometary debris which are intermittently encountered by our planet (see below). It is well known of course that the "fireball" phenomenon is not intrinsically dangerous and it is clear that Seneca looked upon these serious occurrences as involving rather modest "lightning bolts" which did us no harm. This however was not to deny their significance for the explicit warning provided by a regular series of such events was that of further events involving quite extreme fireballs which might sometimes bring about some good by causing damage to another party. Modest bolts did not therefore exclude the possibility of mightier bolts at the next occurrence in a revealed series of occurrences. Specifically relying upon the knowledge of the Etruscans, Seneca was evidently aware of far more calamitous bolts such as would "destroy whatever it strikes and, particularly, alter the state of private and public affairs". Revelation, it is clear, presented the possibility of large scale destruction but Seneca is at pains to provide relief for his oppressed fellow citizens by placing a positive slant on such happenings e.g. by setting an example through stoical resolve in the presence of such menace and by emphasising only the possibility of harm to others. This apparent tendency towards deviousness to place a positive (or teleological) slant on catastrophe, to pour oil on what otherwise might be seen in wholly negative terms, to impose order on chaos, to override cosmological action with public morality, was evidently as much at home amidst the imperial ambitions of Augustan Rome as amidst those of Alexandrian Greece. The Greek approach to the problem however, as we shall see (Section 8), was altogether more subtle. It is perhaps interesting to reflect that both Seneca and Newton attained academic distinction through their ability to place comets and fireballs in clearer perspective than their predecessors. Both furthered their careers and influence as thinkers and advisers at the heart of fledgling empires in their ascendancy. Both went on to write at length on the matter of lights in the sky and what they revealed. In both cases, the new glimmer of celestial understanding was to be set aside while the new parsimony which had expressed itself nationally in stoical and puritanical resolve was to be abandoned in favour of a liberal outlook and the new cosmically untroubled mil-lennium.
4. NEAR-MISS COMETS AND THEIR APOCALYPTIC
The facts of revelation tell us there are few grounds for sing the leaders of nations and empires in the past, together with their advisers (astronomers), were in the habit of regarding encounters with comets as either the only or the most likely celestial threat to civilization. Ordinary comets do of course happen to be the commonest independent bodies of interplanetary space to be readily seen from Earth as well as being the smallest independent bodies (at typical speeds of encounter with the Earth) capable of producing globally significant damage. It is certainly permissible therefore to suppose that perhaps one or even two cometary disasters of global extent may have chanced to be widely observed, experienced and remembered since the dawn of civilization i.e. during the past 5000 years. However active comets do not normally strike the Earth more than once per~l0 7 years and even defunct comets and asteroids, which were never readily seen in the past and which are still considered therefore to be irrelevant, do not normally strike the Earth more than once per~10 5 years. It follows that it is really quite implausible to suppose that direct cometary encounters could have continued for millennia to be perceived as a common apocalyptic threat; or that direct asteroidal encounters will be so perceived today. On the other hand, comets which travel in association with defunct or invisible subcometary debris and whose orbits are such as to bring about an occasional close passage by the Earth may give rise to lesser apocalyptic events whose effects are less likely to be global in extent. Under these circumstances, the range of phenomena known as blazing stars, providences or fireballs will sometimes be associated with cometary apparitions and it would be reasonable-without any knowledge of cometary orbits-to regard all comets as potential "signs" of impending disaster. Historical comets would then have sustained a public awareness of apocalypse just as their specific calculated influence nowadays tends to sustain the reverse! More interestingly though, any concentration or host of similar sub-cometary debris (with or without its parent comet) in suitably periodic orbits commensurable with the Earth-i.e. permitting the repetition and prediction of such encounters-would be justifiably regarded as an even more pressing apocalyptic threat than a random comet. Contrary therefore to a general impression which seems to have arisen in the aftermath of Halley and Newton's findings during the seventeenth century, although the perceived threat from comets was then considerably reduced, the sub-cometary apocalyptic threat still remained very much in place. Indeed, if the perception of cometary "signs" was essentially rational, it is most likely to be explained in terms of a valid sub-cometary apocalyptic threat involving a host of debris. In spite of these fairly obvious facts however, and notwithstanding the modern evaluation of encounter frequencies based on impact craters, some astronomers in modern times have continued to identify what might be called a significant low frequency/high energy "apocalyptic threat" as the one which now justifies the development of a full survey programme to discover all the potential near-Earth objects of cometary and asteroidal size ([157;cf 35]). It seems that they regard the nearest of these objects in future (say, during the next century) as the individual hazards requiring possible preemptive elimination on the grounds that their orbits would be too close for comfort! Neither governments nor public have been particularly impressed however by the suggested urgency of such a project since the presumed frequency of actual encounters of this kind is still low. Indeed it is clear that the primary factor of concern in relation to these near passages in the near future is not at all the likelihood of a directly or asteroidal encounter but the likelihood of a sub-cometary or sub-asteroidal apocalyptic threat arising in conjunction with a relatively nearby "sign". By failing to take account of this matter of historical perception, therefore, these astronomers have failed to appreciate a basic reason for conducting the survey and the project has been seriously undersold. A similarly perverse consequence of this confusion over "low frequency" apocalyptic threats is the belief that the historical fear of comets  is trivial on account of its being based on an inaccurate or primitive determination of the hazard's frequency. There is no justification for this view which is evidently based on a profound ignorance of history. Indeed the comparative absence of any direct damage from comets has almost certainly been generally accepted since the beginnings of Sumerian civilization ca 5000 BP. This was probably well understood by Newton 300 years ago though not, as it happens, by his distinguished acolytes Halley and Whiston . If then we credit the leaders of significant nations and their leaders in the past with the historical understanding that is realistically their due and if we accept the frequency with which nations and empires have been seriously traumatized in the past (see below), then it is clear beyond reasonable doubt that the sub-cometary apocalyptic threat must have been the one generally perceived. We do not have far to look in order to quantify this threat. We need only consider the independent bodies of interplanetary space at least 10 times smaller in linear size than ordinary comets and capable of causing biospheric damage on the scale of nations and empires (i.e. with the potential to produce multimegaton events), and those at least 100 times smaller than ordinary comets and capable of producing harmless atmospheric fireballs around the globe (i.e. with the potential to generate multikiloton events). Neither of these categories of interplanetary body is ever readily seen in space and so our understanding of such objects is very largely derived through the recorded encounters with our and other planets and their satellites. Based on the Tunguska and Shoemaker-Levy events this century for example, and the integral flux of such bodies recorded by Lunar craters formed during the course of Earth history, the average global rate of such encounters causing damage on the scale of nations and empires is on the order of about one per century. This however is a simple long-term average which does not do justice to the known disintegration of comets and the actual swarms of debris that give rise to apocalypticism. If most of this debris originates from giant comets and we take account of the known variations in the cometary flux during galactic and human history  then the integral flux during apocalyptic spells is more on the order of about one per decade to one per year. This rate is unlikely to be overestimated especially if we extend our perception of cometary hazards beyond simple explosive effects. First, it is often in the nature of cometary material to retain its (porous) physical structure whilst undergoing slow devolatilisation in space. Secondly, such interplanetary bodies having a mass sufficient to produce multimegaton events close to the ground can also be so fragile as to undergo premature disintegration during the final approach to Earth . Under these circumstances there is something of a global threat to civilization since the incident dust resulting from such premature disintegration may in turn rapidly envelop the Earth, and a temporary veil (lasting years to decades) may then have a significant influence on the climate . When the premature disintegration results in exceptionally fine particles, there is also the possibility of complex cometary chemicals surviving entry to give rise directly to virulent biospheric damage albeit the study of such effects must still be regarded as being in its infancy. If the bulk of these characteristic events is cometary in origin (necessarily reflecting the history of hierarchical disintegration which we associate with the largest cometary bodies settling in inner Solar System space), then it is easy to see why, after all, historical comets were feared. It follows directly from the process of hierarchical disintegration that the incoming celestial bodies to Earth must often be highly bunched in space; and especially so if, as the constitution of cometary dust indicates, they happen to be not particularly robust on account of recent devolatilisation. A near miss by an ordinary comet may therefore virtually guarantee a direct encounter with a significant sub-cometary body and produce damage on the scale of nations or empires. The probability of an encounter with a significant sub-cometary body is itself measurably enhanced when its orbital period is commensurable with the Earth's and the associated swarm of extreme sub-cometary fragments resulting also from disintegration is repeatedly encountered by the Earth so as to produce typical showers of ordinary atmospheric fireballs. In the latter instance of course we can also take it that the originating comet is either defunct or completely fragmented. Whichever is the case, encounters with such swarms of extreme sub-cometary debris are in fact a common feature of terrestrial history and occur in batches every other century or so [1O, 17]. Herein lies the principal apocalyptic threat already discussed and the primary reason now for an observational programme to search out all the defunct comets likely to approach near-Earth space. This issue can be viewed from another perspective. Astronomers now calculate on the basis of several hundred Earth-crossing asteroids and defunct comets which have been detected during the Space Age (mostly, in fact, within the last decade) that there are several thousand such bodies yet to be discovered. Up to 10 per cent or so of these objects on present reckoning may be derived from the latest giant comet to undergo hierarchical disintegration in inner Solar System space and are believed to be associated with the so-called Taurid meteoroid stream "complex" [19, 6, 70]. Originally identified this century as a clutch of short-period, low inclination, highly eccentric meteor streams extending over a sector of cis-Jovian space, whose orbital tracks directed to and from perihelion are concentrated within a couple of months centered on early November and late June respectively, the Taurid complex is now known to comprise a full range of sub-cometary or meteoroidal debris, most of which is defunct. The "giant comet" source has by now virtually disappeared since the hierarchical disintegration is a rapid process, comically speaking. Indeed the hundred or so objects which the stated 10 per cent or so represent cannot themselves be regarded as much of a threat to civilization since they strike the Earth at the rate of about once per~10 6 years and are therefore likely to be removed by continuing disintegration before any such collision occurs! On the other hand, this hundred or so objects from a system undergoing hierarchical disintegration is bound to be associated with many more such objects which have themselves already undergone fragmentation and which continue to exist individually as coherent batches or hosts of sub-cometary debris. Earth "pseudo-encounters" with the unoccupied centers of these hosts which make up the bulk of the Taurid complex are thus likely to be occurring at the rate of about once per~10 5 years. This rate is to be compared with the ordinary penetration of such hosts which seems to be occurring at the rate of about once per~10 2 years. The implication is that any Taurid host with a source which either does or does not any longer exist and which passes within about 300,000 kilometers of the Earth, roughly three quarters of the distance to the Moon, is potentially an apocalyptic threat. This calculation is necessarily crude at the present time due to the absence of any Spaceguard programme  to improve its precision, but the distance of nearest approach during recent close passages by near-Earth objects  does appear to indicate the "lunar sphere" may well be critical so far as the typical batches of encounters with individual hosts are concerned. In other words, it would not be surprising now if the discovery of a new asteroid in the Taurid complex which passes between the Earth and Moon also coincides with the revelation of a batch of encounters with its host of subcometary debris. Indeed if one encounter with such a batch were relatively close to the defunct cometary source, one might well expect to observe the latter's ghostly passage from horizon to horizon in association with a faintly luminous tail amidst the occasional blazes of light across the sky as otherwise invisible host members encounter the Earth's atmosphere and produce fireballs. The characteristic feature of each such batch is an individual host of sub-cometary (or subasteroidal) debris in elliptical orbit around the Sun which is repeatedly and regularly intercepted by the Earth over a timesscale of about a century, anything say between 50 and 150 years. Such interceptions are likely to be in accordance fairly frequently with a simple orbital commensurability between the host and the earth e.g. at intervals of 13, 10 or 7 years, say, such as are associated with typical meteoroids with orbital periods of 3 1 / 4 , 3 1 / 3 or 3 1 / 2 years respectively. Such patterns of encounter, limited by a near commensurability and by a traverse time due to relative orbital precession between the host and the Earth will evidently result in repeated enhancements in the observed flux of fireballs and constitute a typical revelation. In such instances there is really no question as to the fact of possible encounters with larger meteoroids in the near future, only uncertainty as to the location, magnitude and frequency of devastation. The fear of apocalypse of course will be engendered by expert opinion which will naturally be encouraged to provide its most accurate assessment (necessarily uncertain!) of the realistic risk. Apocalyptic fear in other words is not ordinarily driven by charlatans and will inevitably continue until at least the peak density of the meteoroidal host has been traversed. The extreme subcometary bodies are not in themselves dangerous of course (cf Section 3) since they produce only relatively weak fireballs or clouds of dust and chemicals very high in the atmosphere. They nevertheless signify the presence of a proportion of ordinary sub-cometary bodies capable of producing very much more powerful fireballs closer to the surface of the Earth (i.e. at the level of multimegaton events) and high-level dust- veils severely influencing global climate. Let us recapitulate here. By failing to recognise revelations and the apocalyptic record (Section 3) and by failing to consider their potentially rapid disintegration when reflecting on the effects of asteroids and defunct comets (Section 4), modern astronomers and historians have been able to construct a largely uneventful history for mankind which is in keeping with the perceived absence of any future trauma . Government and society can take a good deal of comfort from this beguiling scheme, of course, but the disintegration of comets is also an established physical property of these objects  and it has been known for some thirty years that a recent giant comet is necessary to explain the extreme over-abundance of sub-cometary material in inner Solar System space . It is clear that the full implications of comets to society and civilization can no longer be ignored.
5. HOSTS OF VARYING DEGREE
Modern governments and their advisers (astronomers) are familiar enough with the situation that prevails during the normal course of events when there is no celestial threat. Thus it is well known that monastic and suicidal escapism will from time to time overtake millenarian sects and their like in a variety of disturbing forms. The escapism though commonly arises among highly rational and well organized societies which dissociate themselves from the mainstream on grounds which often seem at first to be acceptable within the normal standards of tolerance and freedom. Under these circumstances the mainstream authority is clearly expected to give only a suitably proportionate response to any deviation from civilized custom that arises and a mere tendency towards escapism is not of itself likely to be the signal for any decisive action. However the "kneejerk" character of most of the official reaction which ensues when a deviation is no longer perceived to be acceptable can often be more disturbing than the deviation itself and a situation can therefore arise in which the supposedly principal stabilizing influence within society (its government) does in fact become its principal destabilizing influence. Even on a limited scale, when there is no celestial threat, this turn of events adequately illustrates the nature of the problem confronted by mankind . Indeed governments and their advisers are evidently not very familiar with the documented occasions during the course of history when mass escapism very clearly arose and it is obvious therefore that there can be few grounds for confidence regarding the likely official response when such occasions arise again in future. The point here is that there have been frequent occasions in the past when it is clear that virtually the whole population has been concerned as to the accuracy of an apocalyptic prediction and has undergone widespread social disintegration-even to the extent that all semblance of political control was lost and overlordship soon passed to an alternative national or foreign authority . It is very hard to believe an uninformed government will have any success in future confronting mass escapism when apocalypticism once again appears. At the heart of these severe social breakdowns there clearly emerge deep theological concerns and it is a matter of historical fact that contemporary analysts often seek to alleviate the celestial traumatization of nations by propounding explanations of the revelations which offer some degree of emotional release from the danger (often known as "soothsaying" in the past). Two primary explanations seem to be dominant (see below). Both evidently start from the assumption that one is dealing with a manifestly obvious phenomenon. On the one hand it is claimed that the danger is selective and will not apply to "chosen people" (the doctrine of predestination), on the other hand it is claimed that the danger is more apparent than real or that the manifest phenomena are of a spiritual or disembodied character, and are not to be likened to the behaviour of ordinary matter (the doctrine of providence). The recourse to such desperate expedients, seemingly attractive to the intellectual class , is by no means guaranteed to succeed and the debate is usually left unresolved. Nevertheless the debates clearly arise in the context of apocalyptic host encounters and commonly degenerate into a state of civil unrest and revolution if not outright war. The resulting pattern of secular historiography implied by the successive batches of encounters with such hosts, admitting a stepfunction in the evolutionary response of civilization, evidently allows for the periods of eschatological concern which are known to punctuate the course of history . Even at the best of times, of course, it is normal for nations to engage in war and we cannot necessarily expect that the correlation perceived here between apocalyptic/climatological events and their social consequences will be unalloyed by such consequences due to other factors. Nevertheless the tendency to civil unrest under specific, extreme, environmental conditions may will be so decisive as to raise the question whether these critical junctures in history when the reins of power are otherwise unaccountably relinquished in favour of new regimes (e.g. 165O, 1790 and 1850) are also associated with general depressions in global temperature (i.e. mini-ice ages) as expected. To explore this pattern of history further we need to clothe our astrophysical model with a bit more detail. Much hangs, it would now appear, on the actual number of multimegaton airbursts or severe dust-veils which occur around the globe in association with typical meteoroidal hosts. For, let us say, ~100 such incidents in as many year (~75 over the ocean), almost every nation around the "glob" is likely to be directly or indirectly affected by a localized and/or global catastrophe tending to compound and exaggerate the local effects of traumatization through physical destruction and demographic loss e.g. by the enforced movement of whole peoples. Indeed we might expect that the civilizations associated with the largest empires under tines. circumstances will tend to collapse or, at best, metamorphose. On the other hand, for ~10 such incidents during; similar period of time (~7 over the ocean), large groups of nations around the globe will not be affected by localized catastrophes thereby limiting many peoples to the effects of traumatization alone, possibly allowing many nations to remain in a state of relative equilibrium-even to the extent of permitting large empires to consolidate once again. It follows then that a history of successive encounters with ordinary apocalyptic hosts which includes occasional encounters with more substantial hosts might impose; sequence of repeated national traumatizations interspersed with an occasional massive global collapse of civilization This amounts to a pattern of history in which civilization repeatedly undergo "Dark Age" declines widely separated in time whilst also displaying a subsequent tendency toward the regrouping of nations during the millennial aftermath of "Dark Ages" which leads to the fashioning of new empire, and civilizations. Indeed, we might even consider a history of this kind to apply to the fifth century collapse of the Roman Empire and the subsequent "recovery" of Western civilization in its wake. If so, we might also recognize an earlier example of such collapse applied to the Sumerian Empire towards the end of the third millennium BC and the subsequent "recovery" of the Fertile Crescent in its wake With this as our broad model, it is not without significance perhaps that cuneiform scholarship survived the first collapse ca 2000 BC to be the main bearer of astronomical wisdom until almost the time of Christ. Likewise we find Latin scholarship surviving the second collapse ca 400-601 AD to become the main bearer of astronomical wisdom in the West until the time of the Enlightenment. To the Enlightenment's uninitiated of course, this model has all the appearances of being a highly fanciful scenario. To some, it might even be unacceptable a priori because it makes; strong but highly depressing statement about the likely future state of civilization. Nevertheless it is clear the modern historians have never digested the full implication of past celestial signs and modern astrophysical insight concerning the general state of our celestial environment Indeed, with notable exceptions , they have purposely turned a blind eye towards the apocalyptic record. It is a scenario that we shall need to keep in mind therefore as we continue our present review.
6. MODERN HOSTS AND THE COLLAPSE OF
Nations habitually jostle for position on the world-stage Their individual purpose, it is apparent, is to maintain indefinite control over a section of the globe. In recognition of the various constraints under which each operates, it is customary for nations to act in concert amongst themselves so as to uphold an orderly state of dynamic equilibrium Preserving the global status quo, in other words, is; favoured way of maintaining national control and hence national survival. The key to a modern nation's success in this continual struggle is evidently the government and the institutions through which the power of the people is effectively represented. Public opinion of course is, by it very nature, an elusive beast and while it is commonplace for modern governments to claim to represent people as a whole, such is the normal pace of events both government and people in practice usually defer to the well advantaged and to the well armed. As was perhaps more evident among ancient regimes in the past, therefore, it is aristocracies of a kind which generally hold the reins of national and international power. For such aristocracies, the ups and downs of nations through the balance of trade, armed aggression, natural disasters and so on are all part of the normal tapestry of events. Aristocracies indeed are sufficiently robust that even a global war may do relatively little to upset much of the status quo. Likewise, the status quo is hardly perturbed by a degree of substantial migration and mass genocide. During the twentieth century, for example, some 12 billion human lives have been lived and lost; and of these, some 80 million have been lost as a result of localized "end-time" revolutions largely provoked by fanatics . Locally, this appalling statistic involves a demographic recession of, say, 10-50 per cent but globally it is less than 1 per cent. It is important therefore that we remain clear as to the level of catastrophe which is here discussed. The twentieth century by this and any other global reckoning is evidently somewhat uneventful! As a consequence it is those longer periods of upheaval around the globe to which mankind has intermittently succumbed during the course of history that aristocracies, and hence nations, have the greatest cause to fear: extended periods of famine, epidemic and war during which the demographic adjustments and losses globally increase above the customary background level (a few per cent) by at least an order of magnitude to, say, 10-20 per cent. The three latest such periods, each lasting about 50 years, are centered around 1650, 1790 and 1850  and closely match the three latest enhancements of the meteoroidal input to Earth . Frequently identified as marking the starts of the English, French and German enlightenments respectively, these pivotal periods are of course historically conspicuous on ac-count of the global upheaval and social revolution by which they are commonly characterised. It is a curiosity of the twentieth century however, possibly on account of its essentially uneventful character, that Western civilization now tends to spurn any connection between these social breakdowns and the celestial signs with which they are temporally associated. Admittedly some scholars have drawn attention to the climatological downturns at these epochs  which may of course be of celestial origin. Such proposals however remain the exception rather than the rule. In particular, historians fail to make anything of the greatly increased eschatological concern of these times, i.e. a very definite tendency on the part of those living to see critical aspects of their environment in a process of very rapid and terminal change . Rather, in order to explain the upheavals, it is customary nowadays to invoke some kind of global breakdown in the diplomatic processes of representative government occasioned by widespread internal collapse, albeit any such so called "whig interpretation of history" is now thought to be phenomenologically inconsistent and therefore seriously unsubstantiated (e.g. :see also Section 8). The whig interpretation of history, in particular its theoretical justification, derives from the highly respected philosophy of the well known English empiricists (namely Locke, Berkeley and Hume) which first emerged as the seventeenth century enhancement of the meteoroidal input to Earth went into decline. The acclaimed purpose of the new philosophy was "a grand onslaught on tradition, arbitrary government, and ecclesiastical authority in so far as all these things supported the old order which had been defeated once in 1640 and again in 1688" . The victors of the English Civil War and Glorious Revolution saw this philosophy therefore as their justification in particular, a step back from the fundamentalist excesses and outworn authoritarianism of the Interregnum and a step forward to the millennialist dreams and "common sense" calculation of the Future. The foundation of the new philosophy was a general theory of knowledge based upon the empirical procedures of natural science rather than the divine ordinances of old. religious rationalism which dispensed with miracles and the whole paraphernalia of "supernaturalism" (i.e. with revelations) "while continuing to believe in God" . Upon such rationalism was then duly founded the new English Monarchy, the French Republic and the United States of America: new habits of thinking in which aristocracies and nations around the world would come to operate within a framework of political and economic liberalism. This is not to say of course that these nations established a secure political and economic process based on such founding principles since, in practice, they proved surprisingly defective. Thus while it may be taken that an appeal to empirical procedures would introduce an element of precision into the measured relationship between apparently connected parameters, the physical connections would themselves be subject to choice and pragmatic judgment with extrapolated consequences that were not necessarily secure. A century or so after the English empiricists had embarked upon their line of inquiry, it was clear that the more or less exclusive dependence of such rationalism on natural science had run into severe theoretical difficulties; so much so that the whole line of thinking was deemed basically irrelevant by the influential school of German philosophers (namely Kant, Hegel and Marx). They essentially recognized that public affairs must in addition respect the empirical procedures of social science and hence rational metaphysics as much as rational physics, the unavoidable human tendency to base political action on supposition as much as on reality. Out of this were to grow the ideas of dialectical materialism and a crucial explanation of the great upheavals of history in terms of the natural instabilities that arise within and among nations through social and economic determinism. As is well known, the well nigh exclusive appeal to such determinism is now commonplace in the service of modern history and modern politics, tending to displace any related intellectual discipline in which an appeal to physical determinism would also be involved. However, in arriving at their underlying principles, both the English empiricists and the German idealists have clearly relied upon a purely metaphysical interpretation of the recorded "miraculous" or "supernatural" phenomena of history. They have in effect taken a view as to the unphysical nature of "revelations" which modern astrophysicists are hardly able to endorse. Here then is the basic reason why modern aristocracies (i.e. modern governments and their advisers) now largely overlook the evidence of meteoroidal inputs and the recurrence of eschatological concern during the great upheavals of recorded history. Indeed the original arguments on which the English empiricists and German idealists based their influential philosophies are now essentially forgotten. To recover these arguments, we need to recognise that it was the original cognoscenti of the Royal Society in London who first took a disparaging view of meteoroidal inputs and apocalyptic fears, blaming the public reaction of the contemporary English in particular . These cognoscenti were clearly of a whiggish disposition and evidently did take such a view out of disrespect for the earlier intellectual support which was given fundamentalism rather than millennialism by the London Society of Astrologers [391. The latter was disbanded at the end of the Interregnum and replaced by the Royal Society . And in due course it did seem that this new view of things had been comprehensively endorsed when the new society's eventual president of distinction Newton, failed to support his younger colleagues Halley and Whiston on the occasion of the publication of their ideas concerning a sustained cometary threat to Earth during the course of history . Newton however was also a theological non-conformist and it is well known that he attached great significance to the known history of revelations (see below); thus he appears to have inclined more to the teleological or Calvinist view that the danger was predestined and selective rather than to the emerging mainstream view that it was more apparent than real. This should not be taken to imply an altogether blind faith associated with the typical puritanical outlook: rather it should be taken to imply a form of deism in which the cosmos naturally produces apocalyptic hosts to which the conduct of suitably guided societies needs to be adequately matched. In other words, Newton can be identified with those for whom eschatological concern and global upheaval were still primary considerations and it was the perceived business of society to survive apocalyptic terror as well as the perceived business of individuals belonging to society to make an earnest commitment or general covenant towards this end. Thus we are dealing with an era that still saw deism and teleology as two sides of the same coin, both operating in accordance with essentially the same natural law, a natural law moreover which applied to society as a whole and to which individuals exercising freedom of choice either conformed (good) or did not (evil). Later Newton was to publish his own ideas about the history of revelations and eschatological fear, essentially implicating an enhanced meteoroidal input of the kind observed during the course of his own lifetime [62, 8]. Broadly speaking these ideas were very closely aligned with those of late medieval scholarship in Europe  and hence with the Sumerian and Babylonian tradition stretching back to the very foundation of civilization . Under these circumstances, to the extent that aristocratic governance is a natural condition of mankind (just as wolves hunt in packs!) and eschatology is a vital academic discipline associated with the activities of ancient regimes (from~2500 BC-1800 AD), it is important that we reconsider the social imperatives once believed to arise in response to recognised celestial inputs. Indeed, all the more so if, as now seems likely, Newton at the end of his career was not properly understood by his younger contemporaries. Although English empiricism eventually continued in the tradition of anti-apocalypticism, there can be little doubt as to its emergence in the knowledge of near-miss comets and apocalyptic hosts, causing nations to collapse. Thus, in likely awareness of revelations and their apocalyptic implications (Section 5) whilst reflecting on the attitude society should adopt (Section 6), the English empiricists evidently introduced a blatantly metaphysical interpretation of revelations which the remainder of Western civilisation proceeded to single out as advantageous during the course of two further periods of global upheaval around 1790 and 1850. It seems that a whiggish establishment which was initially expected to guide society in accordance with an apocalyptic fear which was historical and real (a la Locke: Section 7) was then privately persuaded that revelations were of no material substance in accordance with a teleological cosmology introduced by the "gnostic" Greeks (a la Berkeley: Section 8). We shall see that this persuasion was not altogether irrational.
7. THE PERCEPTION OF "LAST
Any specification of these longer periods of upheaval around the globe (Section 6) in terms of a parochial (i.e. purely national) enlightenment can of course be very misleading. Thus we cannot be too enthusiastic about so called English French and German enlightenments when some scholars would perhaps justifiably connect the English and American upheavals of the seventeenth and eighteenth centuries with a general advance of predominantly Anglo-Saxon culture which French reactionaries did not at first acknowledge  but which was then admitted by most European nations during the upheaval of-the nineteenth century. In point of fact, the successive enlightenments here are not as "progressive" as many commentators might now be in-clined to claim since the post-revolutionary French enlightenment was in practice something of a wider European reaction against the English enlightenment which then failed to secure intellectual support. Thus the successive enlightenments perceived as revolutions were more in the nature of a whiggish reaction to apocalypticism as in England which later spread to America and then to Europe and to the rest of British Isles to become the orthodoxy of Western civilization based upon rather specific, pragmatic principles dictated by Berkeley rather than by Locke (see Section 8). Indeed, if we take an even more parochial view and regard these longer periods of upheaval as corresponding locally to the so-called English Scottish and Irish enlightenments respectively, we can well see that these advances are probably not unconnected with the severity of the immediately preceding climatic downturns and hence possibly with the corresponding meteoroidal inputs. These were prominent enough within the British Isles to have implied a possible link between the social plights of each people in turn and the conspicuously adverse social conditions of the little ice-age, the highland clearances and the potato famine respectively . There are problems evidently in handling such diversity among the parameters involved when seeking historical patterns in social behaviour but the rather similar correlations between astrophysical, geophysical, social and intellectual developments may seem well enough founded now to raise serious questions regarding the current linear model of historical evolution and to justify seeking to reinstate a cyclic model of history involving the successive incidence of apocalypse followed by renaissance . Such a model does not necessarily imply renaissances which are progressive however and it is entirely possible that the apocalyptic experience provokes an increase or decrease in the authority or freedom with which society is controlled depending on the actual extent to which society believes the cosmos (or divinity) was involved. With such a model, the intermittent and serious breakdown of society is of course the more readily understood and we can perhaps appreciate why our ancestors were so ready to concede mankind's innate propensity towards extreme antisocial behaviour in the presence of disturbing and terrifying conditions-the unavoidable disposition to "sin"-which could nevertheless be greatly alleviated by the creation of a rigidly structured society and by the early inculcation of suitable knowledge and social customs. The converse of course, attractive to Western civilization today, allows for a greater degree of individual freedom and toleration of individual habits within society whilst apparently failing to recognize the practical difficulties that then arise with the application of restraint in the presence of apocalyptic fear. Long accepted ideas about eschatology (the destiny of man after death) and kingship connected with the practices of omen astrology and the perception of cosmic catastrophe ("last times") which now seem strange did evidently arise however in association with ideas about group salvation (i.e. specifically favouring aristocracies) from prolonged cosmic terror . Furthermore, accounts of the afterlife given in the ancient mythologies consistently reflect a situation of hopelessness and despair. These were not originally accounts of punishment in hell for misdeeds of the wicked, however, but of ordinary mortals transferred to a postmortem environment, stories of inexplicable survival amidst equally inexplicable extinction . The dreadful warning was that of a forthcoming state of the world, inevitably represented as a prolongation ad infinitum of tedium followed by terror, such as had already been experienced. The form of governance known as "ancient regime", essentially recognising cosmic terror and serving aristocracies, can in fact be traced to its inception during the early stages of the Sumerian Empire and thereby to the very beginnings of systematic knowledge and civilization itself. As such it admitted the bodies of knowledge now referred to as omen astrology  and es-chatology . It is customary nowadays of course to dismiss these branches of knowledge as irrelevant but, contrary to a popular misconception, there are no serious grounds for supposing the essence of this secular knowledge is other than empirically based and subject to scientific interpretation in the modern sense of these terms . In fact, the formal linkage of omen astrology, eschatology and "kingship" in the past was clearly fundamental to aristocracies with pretensions to hegemony. Territory submitted to rule by hegemony which is so extensive as to be vulnerable to the debilitating influence of apocalypse will commonly put the survival of a mere aristocracy and its possessions seriously at risk. It is no cause for surprise therefore that all aspects of social and intellectual existence in such a culture should have been geared to life beyond the apocalyptic events. The discipline of eschatology moreover was no fanciful diversion: from its inception it dealt with a continuing apocalyptic process by which specific celestial agencies would inevitably reduce mankind and the terrestrial environment to states of mental and physical chaos. By classical times, it was very widely understood that the mightiest of these occurrences took the form of a "universal conflagration" or "flood" at long periodic intervals due to a circulation of celestial bodies which impinged upon the Earth. This was by no means all however since lesser eras during the course of history were also clearly involved, each with its associated "last times" characterized by celestial signs and frightening events as well as by wars, epidemics and famine. Comets on this account were just one category amongst a range of natural phenomena which might be heedlessly associated with the demarcation of critical periods in the course of natural history. Because of the relative frequency of these phenomena it is easy nowadays to imagine our ancestors have always had an exaggerated view therefore of the significance of their particular epoch. While this tendency cannot of course be discounted altogether, the inference is almost certainly misleading since it fails to take account of the primary apocalyptic agency (fireballs) through which the mental anguish generally develops. The point to be emphasised here perhaps is that the "uniformitarian" character of Nature is certainly defensible for a considerable range of phenomena for much of the time but because it is so deeply entrenched on this account, we must not fall into the error of supposing it must therefore apply to every celestial phenomenon. Indeed the clear impression that emerges from the strongly celestial orientation of much mythology and religion, not least during the classical era itself, is of a celestial agency in the past which did strengthen considerably at certain epochs to become traumatic in the extreme and which was then still an awesome prospect in the future (see also Section 5). In contrast any such extreme trauma seem to have been at a reduced level during the Enlightenment while the ancient regime has increasingly appeared to be an irrelevance and thus in a general state of abeyance. Accordingly and until two hundred years ago, virtually all historiography was based upon a globally apocalyptic chronological scheme . A world historical process was clearly envisaged in which ordinary natural processes would continue for the duration of an era until its inevitable termination in "last times". A very ancient pattern of such eras, now attributed to Zoroaster , is usually marked by the Creation (~5500 BC) and subsequently by successive Ages: the Golden (until~3000 BC), the Silver (until~2000 BC), the Bronze (until~1000 BC) and the Iron (until~ BC/AD). A more recent scheme originating with Eusebius and continuing into early modern times  involves a somewhat more elaborate division of time but recognizes also the passage of dominant civilizations: the Babylonians, the (unhistorical) Medes, the Persians, the Greeks and the Romans (~2000 BC-500 AD), followed by the emergence of the Holy Roman Empire (~500-1000 AD) and its renaissance as Western (European) civilization (~1000-1500 AD) subsequently undergoing reformation (~1500-1700 AD) and enlightenment (~1700-1800 AD) prior to its secular emancipation (~1800 AD-the present). One accepts of course that these transitions are to some extent still in general use but any suspicion that they correlate with environmental events has now largely been abandoned. We should not be over-impressed by any apparent precision in these dates. Nevertheless the trend towards shorter eras as we approach the present almost certainly reflects an increased attention to detail regarding the correlation of celestial and terrestrial events. On the other hand, as we have seen, the periods of "last times" can endure for several generations and any chronological scheme involving single dates of demarcation is therefore necessarily imprecise. To gain some idea of its relative precision, we can refer to the most complete record of meteoroidal fireballs during the last~2000 years which is that maintained by Chinese imperial astrologers . This shows substantial enhancements roughly during the two centuries preceding and including the time of Christ (say~150 BC-50 AD), the three centuries including the European Dark Ages (say~350-650 AD), the two centuries that correspond to the bulk of the Crusades (say~1000-1200 AD), the two centuries that precede and include the Reformation (say~1350- 1550 AD), the half century that includes the English Civil War and Interregnum (say~1625-1675 AD), the half- century that includes the American War of Independence and the French Revolution .(say~1765-1815 AD) and the few decades that includes the period of European Revolutions (say~1830 -1860 AD). Most of these enhancements are broadly concentrated in the northern hemisphere months of midsummer (end of June) and early winter (start of November) indicating a likely strong association with the Taurid stream of meteoroids . This can reinforce the impression we are dealing with an incidence of "last times" which is due to hosts of debris ultimately originating from a single celestial agency. Whether the perception of a unified process was sustained in this manner is perhaps not clear but the idea of a celestial agency which intermittently exerts pressure in such a way as to apparently "rude" mankind to greater knowledge and understanding during successive stages of comparative calm but then also, at longer intervals, introduces a level of devastation that causes civilization to experience a particularly serious recession (cf the model of Section 5) was evidently commonplace. The details of apocalypticism indeed essentially upheld a picture of civilization in which the low-level evolution of mankind advances by a process of punctuated equilibrium in accordance with a random distribution of encounters between the Earth and Taurid hosts; but with the added feature of a longer term cycle as the greatest concentration of material within the Taurid stream apparently swings back and forth in the sky (see Section 9), regularly delivering mankind into the successive depths of "Dark Age" every few thousand years or so while passing between the corresponding shallows of "enlightenment". This periodic timescale is of course very long in comparison with the human lifetime but it appears to have represented an additional yet certain threat in contrast to the uncertainty of random punctuations thus reinforcing the general incidence of mental anguish in the past. The important point to be emphasised here perhaps is that the incidence of "last times" in the past was never perceived to be a trifling matter, more an integral part of a supposedly real catastrophic evolutionary scheme which was generally understood to involve both "punctuations" and "cycles". contrary to a current general impression therefore, the main precepts of the nineteenth century uniformitarianism- catastrophism debate relating to geological and biological evolution were already essentially in place, albeit in relation to much shorter timescales and seemingly more germane effects.
8. THE DISEMBODIMENT OF
The evolution of species is either "progressive" or "punctuational" depending whether the dominant environmental processes at play during the course of extinction and speciation are "uniformitarian" or "catastrophic". In principle the dominant environmental processes at play can be biological or physical, whence a catastrophe likely arises on account of an internal (biological) instability or an external (physical) perturbation. Likewise the evolution of civilization either progressive or punctuational depending whether the dominant environmental process at play is uniformitarian or catastrophic. Catastrophes in this case however, as we have seen, refer to the rise and fall of "core societies" (aristocracies). Recent historians on the other hand have not generally looked to physical factors (e.g. climate, revelations etc.) as the principal cause of such rise and fall with the result that the punctuational form of historiography that has been in place for more than two hundred years is one in which the longer periods of upheaval are mostly understood in terms of purely social factors in general accordance with the "whig interpretation of history". This widely accepted form of historiography clearly takes its lead from the English empiricists and German rationalists and, as we have already noted (Section 6), is currently undergoing critical re-evaluation . An evidently fundamental issue however affecting the way this type of historiography came to be established is to be found in the role of biblical scholarship during the eighteenth century. Thus the Anglican biblical scholars of this period, many of them bishops and members of the whiggish ascendancy paying lip-service to the intellectual leadership of Locke and Newton, were heirs to a contemporary historical tradition which was made particularly manifest by the Protestant Bible, combining both the New and Old Testaments. The episodic character of history as expressed through the successive books of this Bible, indicating separate periods of interaction between the divine cosmos and mankind, was palpably reinforced as such through a perceived series of so-called "Christian evidences" cumulatively seen as providing "proof" of the fact in the manner of a euclidean text (~4O, 41]cf ). The Bible in other words was widely looked upon as a canon of evidential statements and prophetic utterances-propositions and theorems, one might suppose-which taken together essentially "proved" the given framework of historical knowledge. Interpolated between these statements and utterances of course was to be found the discussion and interpretation that would normally clarify the propositions and theorems in the context of the meaning and implications of the canon as a whole. For the most part, such discussion and interpretation are by way of subsequent commentary on the original canon and were recognized readily enough by their generally moral and literary style. The evidential statements and prophetic utterances on the other hand were clearly understood as the elements of an original, historically updated, document whose textual content plainly identified it as such and which was generally considered to be particularly well preserved. This is not to say however that the meaning of the original document was considered to be immediately apparent. Rather it was accepted that the meaning may have drifted on account of repeated translation and redaction and that it was the business of biblical scholars to discern its true meaning. In other words, despite their substantially unaltered condition, the meaning of the propositions and theorems now had to be inferred as much from the context as from the words and was still a matter for scholarly debate. The whiggish scholars were thus very much aware that "whoever looks into the prophetically writings will find they are generally penned in a very exalted style and oftentimes in such images as cannot admit of literal interpretation" . On the other hand the "exalted style" of the so-called "Christian evidences" was commonly seen as accurately reflecting the often dramatic or overpowering nature of the phenomena referred to, hence their usual interpretation as recorded instances of divine intervention in human affairs. It would be quite out of character with the received theological wisdom of the time however to suppose these "revelations" of divine intervention were in any sense figurative or symbolic. Rather they were perceived as super- natural or extreme celestial events. In other words there can be little doubt that the well preserved historical document subsumed by the Bible was widely perceived as a catalogue of very special celestial phenomena at certain epochs-such as astronomers are now familiar with in the case of the encyclopedic records of ancient Chinese ob-servations of such phenomena-interwoven with a predictive or prophetic model linking together what would otherwise be regarded as distinctive but unconnected events. The modern astrophysicist has little difficulty in comprehending the general principles that underscore such a historical document. After all our modern picture of the universe is itself founded upon a predictive physical model designed to match or "prove" selected observational data in supposedly temporal sequence. The analogy does not end there. For the eighteenth century biblical scholars and their predecessors, like modern astrophysicists, were plainly not unaware of the underlying, supposedly more mundane, framework of natural phenomena upon which this category of more dramatic or supernatural events was superposed . Thus a division of intellectual labour was evidently envisaged in which natural philosophers would largely supervise our understanding of more worldly phenomena and theologians at the top of the intellectual tree would supervise our understanding of divine intervention; that is, the whiggish ascendancy was no different from any other intellectual leadership and was ultimately in business to establish a definitive view of divine material (providence) and divine motion (its dynamic) along with an explanation of how these together were responsible for the special celestial events known as revelations. Soon after the mid-seventeenth century foundation of the Royal Society, as we have seen, Bishop Sprat had remarked upon the widespread concern in England as to the nature of "providences" and "prodigies" (their most extreme version) while others such as Baxter in England and Mather in New England  were advocating procedures whereby "providences" would be systematically observed and recorded over much of the globe. The frequency of meteoric "fireballs" due to the more substantial meteoroidal inputs (see Section 4) was in fact significantly enhanced above the usual background level during the seventeenth century and it can hardly be doubted therefore that these fireballs were the primary objects diverting contemporary attention towards thoughts of "last days" and a very natural association with earlier revelations as recorded in the principal canon of celestial knowledge. Normally of course the providential background is of no greater consequence to mankind than the incidence of lunar and solar eclipses or planetary conjunctions but if it is significantly increased then the occasional prodigy may inject vast amounts of dust into the atmosphere or generate a huge mutimegaton explosion, thereby becoming a very serious hazard to mankind. The well-preserved historical document-the Bible-we may be sure, was widely received as a very vital catalogue of extreme but very real providential events. In fact, the science of celestial mechanics itself emerged from considerations like these relat-ing to divine material and divine motion. Thus it is clearly no accident that Newton's Principia of the seventeenth century, which heralded the enquiries of the eighteenth century biblical scholars, was likewise structured like a euclidean text. It has been said that there was an unprecedented fusion of scientific reasoning and religious thought during the life span of Newton  but, while this may be undeniable, the prospect of an integrated scheme under one set of divine physical laws had been a major component of the Christian intellectual agenda since at least as far back as Aquinas . What is perhaps not so fully appreciated these days, therefore, is the extent of the purely (astro)physical motivation behind much theological inquiry and of how much this represented a continuing desire to comprehend the flux of supposedly divine material, most especially its apocalyptic potential. Thus, by the seventeenth century, it was already recognized that providence would arrive during broad epochs (say 50-150 years) spasmodically distributed throughout the course of history (say at intervals of a few centuries) reaching back to the "deluge" and even to "creation" itself. If the historical analysis of such as Zeigler, Munster and Gifftheil  Ussher, Alsted, Brightman and Mede  and finally Newton  were to be upheld, the whole sequence of "biblical events" was stretched over some 6000 years and there was much to be learned about the future from a suitably careful examination of the past. During these broad epochs, it is clear now that providence would arrive in characteristic but subordinate temporal patterns (i.e. at a particular month and a fixed, relatively small, number of years) such as would readily allow a rather straightforward prediction of the next influx together with such nervous anticipation of the "end of the world" as would be engendered. There was no absolute certainty of course that the "end of the world" would come but there was no mistaking the general pattern of downfall during history associated with these broad epochs. According to this pattern (Section 7), the great kingdoms of the past had succumbed in turn: first Babylonia and Media; then the Persians; later the Greeks, and finally the Romans. The latter of course is not identified in the Book of Revelations but by the sixteenth and seventeenth centuries, the European Protestant movement had essentially added to the list of downfalls the socalled "great apostasy" when the Roman Empire governed from Constantinople failed to retain control of the West and power passed into the hands of the so called "Antichrist" at Rome. Descendants of the massive population displaced into Western Europe during the great apostasy (Franks, Germans, Anglo-Saxons) seem therefore to have been the principal parties to perceive themselves as having been delivered (by the vikings?) into the hands of a huge ecclesiastical empire ruled by a despotic church from Rome. Their protestations evidently took hold alongside a perception of the environment which was most clearly presented in the Books of Daniel and Revelation, containing apocalyptic accounts of a most fearful and terrifying nature. These books, as we have already seen, are representative of a late Babylonian tradition before the time of Christ  which stretches back to the origin of omen astrology itself . This is the very same tradition of course which led Keynes  half a century ago to categorize Newton as the "last of the Babylonians and Sumerians". There can be absolutely no doubt that the Protestant whiggish ascendancy was heir to this tradition as well. But whereas Newton, along with the principal puritanical movements of his time, would look back with considerable horror at the great apostasy and the original Christian sect identified with the apostolic succession which had penetrated and dominated the upper echelons of Roman society by the fourth century, the contemporary trend of whiggish opinion amongst English bishops was evidently towards condoning and reaffirming the critical fifth century decisions of the embryonic Holy Roman Church. The point here is that the Christian sect in question, whilst having gained in political clout as it moved away from the gnostic orthodoxy at the turn of the millennium in which Christ was primarily a cosmological phenomenon , was to use its position of dominance at the great Councils of Ephesus and Chalcedon to ascribe this cosmological phenomenon to a disembodied or spiritual Christ, precisely in accordance with the viewpoint now (re)adopted by the philosopher bishop, one Berkeley. It is well known of course nowadays that Newton subscribed (in private) to the so-called Arian heresy but the implications of this heresy with respect to the physical nature of the cosmological Christ (and hence revelations: see below) are now commonly overlooked by astrophysicists. Thus the basic point at issue amongst the English bishops was the precise interpretation to be given the "Christian evidences". Locke, on the one hand, inclined to the view that we must be dealing with quite exceptional natural events involving real material bodies and that "what is obscure to us may have been perfectly clear to those living at the same time in the past"; whereas Berkeley, on the other hand, argued that "the proper objects of vision constitute an universal language of the Author of Nature" and that "the language of Nature cloth not vary in different ages or nations". Whatever was intended by the biblical records of revelation therefore, it was now supposed by the English bishops on the basis of the proposed immutability of Nature that the associated physical effects of revelation must always be essentially mundane, as the contemporary observation of Nature assuredly asserts. It follows that the dramatic quality of revelation must be understood to denote divine messages in the sky possessing only a spiritual rather than a material content while the processes of Nature must be regarded as essentially uniformitarian. Such disembodied revelations were rather quickly approved by the whiggish ascendancy in England (to be followed by the rest of Western civilization in due course) with the result that physical revelations ceased to receive any intellectual attention and were essentially excluded altogether from the modern system of natural philosophy which came to be known as materialism. Non-physical revelations however incorporated into a philosophical system known as hutchinsonianism [67, 41], were widely accepted and led to an essentially allegorical interpretation of the Bible  which was to become more or less axiomatic whilst also admitting a form of natural philosophy constrained by the principle of uniformitarianism [53, 26]. This farreaching development was opposed during a significant revival of catastrophism between~1790 and~1850 in France [10, 48] and in Scotland  which saw the earliest scientific description of natural selection under the conditions of punctuated equilibrium but which then also saw this development rather quickly expunged from the scientific record . This turn of events is historically significant since it demonstrates Darwin's particular concern, critical to the English en-lightenment, which was to develop an account of natural selection compatible with uniformi-tarianism. The nineteenth century decline of catastrophism was essentially a repetition therefore of the early eighteenth century rejection of revelation as expressed through the differing views of Locke and Berkeley. During the twentieth century, Darwinian uniformitarianism became firmly established until the study of impact craters suggested a significant role for cosmic catastrophes underlying the course of evolution on geological timescales. During the same period, the physical study of fireballs has been reinstated but the findings nevertheless have tended to remain independent of the study of revelations with the result that three principal forms of natural philosophy relating to evolution on geological and historical timescales can now be discerned. These are (1) uniformitarianism-cum-hutchinsonianism (this essentially remains the mainstream view); (2) catastrophism-cum-hutchinsonianism [13, 58]; and (3) catastrophism [20, 22]. The differences of opinion rendered explicit here, though not intractable (see Section 9), remain a firmly established feature of modern enlightenment. The absence apparently of any satisfactory resolution to the problem is marked by a particularly vehement tradition within modern scholarship seeking to preserve anti-apocalypticism. Here it only remains to consider the physical theory of revelations that is permitted by their evidently material and historical nature. The city of Alexandria, through its geographical location, eventually came to be singularly well placed for the scholars of imperial Greece undertaking comparative studies of the information emanating from the great civilizations of the Near East. Prominent amongst these scholars were the so-called "gnostics" who brought together the various common strands of Chaldean astrology, Zoroastrian dualism, Egyptian mythology, Jewish apocalypticism and Hellenistic speculation to construct a unified system of cosmology (and religion) which is now known to have been highly influential and extremely widespread across the temperate zone of three continents (,Chapter 3 in particular). The existence of this unified cosmology almost certainly betokens the spread of a unified (secular) culture as well , thus pointing to an early example of the kind of growth that we now associate with modern science and enlightenment at the heart of Western civilization. The underlying perception behind this gnostic or imperial cosmology was evidently that of the heavens which included an upper region (or celestial sphere: the stars), an intermediate region (or ecliptic plane: the planets) and a lower region (central to the sphere: including the Sun and Moon). The various visible components of these regions were clearly perceived as owing their physical existence and creation to a former unitary body, the cosmological Christ. Creation was not a once-and-for-all operation however but involved a process of hierarchical disintegration known as "emanation" which also led to the formation of other substantial celestial features, no longer extant. Foremost here was a circular embankment ("the flaming walls") in the form of a broad belt around the ecliptic, apparently just within or at the celestial sphere, which marked "the boundary" of the known universe. This boundary was also essentially continuous with a narrow bridge ("the rope of angels") which connected the circular embankment directly to the centre of the celestial sphere, thus joining the upper and lower regions of the heavens. This boundary, including the bridge, appears to have been once visualized as a very luminous, material construct resulting from the emanations of the cosmological Christ which. however, was not entirely uniform in its general appearance. Thus it was made up of temporary shapes and evolving patterns, one such apparently including Christ itself in circulation between the heavens above and below. The lowest step of the bridge perceived as a ladder did eventually mark the most critical phase of emanation from the cosmological Christ. This critical phase was clearly taken to be an extremely dramatic event. It not only captured the attention of Earthlings below but was evidently considered to be the primary stimulus giving rise to the multiplicity of cosmic mythologies among the various nations of the known world. Indeed the event itself was a veritable "Pandora's Box" being the palpable focus for an outpouring of visible celestial entities whose existence thereafter appeared to capture the attention of witnesses all round the globe. Putting these mythologies together, the emanation was ultimately perceived by the gnostics to be in a direction essentially orthogonal to the line of the narrow bridge, projecting first on one side and then on the other to produce an identifiable "cross". This cross was never an isolated feature of the sky however (e.g. see Plato's "Timaeus": ) since it evidently connected with a more extended celestial structure. This structure, it would appear, corresponded to a closely bunched hierarchy of so called "archons" (archaeons) and "aeons"-emasculated versions, apparently, of the archangels and angels who occupied the narrow bridge-whose rather similar orbital paths therefore intersected at a point on the bridge and whose distribution otherwise was such as to dominate the lower region of the heavens. The effect of the dramatic event there-ore was to introduce new features in the sky which were a pale reflection of the earlier, more luminous, constructs and which furthermore did more obviously affect mankind. In fact these aeons were evidently regarded as hostile to the Earth and mankind and it was their emanations in particular which were subsequently associated with revelations and apocalyptic terror.
It eventually came to be well understood of course that revelations were equivocal in respect of the incidence of catastrophe and it was the Greeks apparently, as imperialists, who first sought to turn the incidence of potential non- catastrophe to public advantage by systematically painting revelations in wholly optimistic terms. The Greeks long before had taken the formal step of separating government and academe, and while it is clear the latter then took rationalism to even greater heights than before, the demands on government in the face of apocalyptic terror (cf the banishment of Anaxagoras: ) evidently meant a degree of sophistry was not out of place when presenting the realities of the cosmos. Organized religion and stage managed miracles indeed became endemic amongst the cosmopolitan Greeks  and we cannot therefore be surprised at the cosmological phenomena which were embellished, i.e.. a fireball phenomenon which became providential rather than fickle, an original cosmological Christ whose body and initial emanations became spiritualized, good and divine, a fallen angel whose cross (regarded as Christ's burden) gave rise to the lower region of heaven as well as to mankind on Earth, both perceived as evolutionary stages of a defective material condition to be suffered by the entrained spirit; and a subsequent resurrection of the cosmological Christ perceived as an example to all other fallen spirits (i.e. all human souls) whose route back to the upper region of heaven needed to be made manifest. Nowadays of course we are more familiar with the teleological or moral philosophical aspects of the theological rationale that was invoked by way of explanation for the known cosmological facts; conversely we are rather less familiar with the interesting theoretical notion of a material condition which is some kind of negative or defective attribute of the (primary) spiritual condition, tending also to forget that we are now the beneficiaries of an intellectually hard won physical science in which only the (positive) material world exists. In fact, the significance of all the theoretical detail here must be the greater on account of its having been clearly related to the known cosmological facts. For we can hardly suppose that the Greek imperialists would expect their version of "gnosticism" to carry conviction with subordinate peoples unless the available cosmic mythology were very adequately explained. It has already been noted that the influence of gnosticism was wide: indeed it flourished for centuries alongside the rise of the Holy Roman Church. Subsequent understandings of apocalypticism would be expected therefore to match gnostic cosmology to a plausible or acceptable extent. It is hardly surprising that late medieval Protestant heresy, inasmuch as it inclined to hard-nosed materialism, was a principal bearer of the original as opposed to the embellished gnostic cosmology which an integral part of Christian theology. To a later generation of imperialists in another place, however, who no longer knew which aspects of cosmology had been stage-managed and why some subtle aspects of gnosticism became heretical, it was a matter of simplicity, albeit of surprise, to save the surviving appearances by ultimately spiritualizing "the defective material condition" of the revelations that still remained: in other words, it was a matter of simplicity for English bishops, still rather illversed in the basics of Newtonian science, to disembody the most immediate parts of the observed cosmological environment for the sake of "a language of Nature" which "cloth not vary in different ages or nations" and for the sake of an anti-apocalyptic environment which they sought to preserve.
9. APOCALYPTICISM UNRAVELLED
We should not be too hard on English bishops! Subsequently this inclination to disembody the most immediate parts, if not all, of the observed cosmological environment has only been matched by academe's solicitude for secularisation: indeed it is something of a surprise nowadays to realise that this inclination can officially still be very much in place. Darwin and Huxley, as we have seen, were prominent nineteenth century influences who, by championing uniformitarianism- cum-hutchinsonianism, effectively made sure cosmological astrophysics remained disconnected from Earthbound physics right up to the Second World War. Before the Second World War, for example, Britain's most distinguished physicist (Rutherford) could easily set aside Britain's most distinguished astrophysicist (Eddington) as a mystic because he was all too obviously perceived as peddling a disembodied world. Thus did a founding architect of the knowledge that gave us "the bomb" deal with a founding architect of the knowledge that gave us "the expanding universe". After the Second World War however a mankind ridden with guilt disowned "the bomb" and as a consequence physicists were no longer held in high esteem. Britain's most influential astrophysicist (Woolley) could thus immediately position himself within the fastness of the cosmic arena and look across with disdain at the rocket-men on their new frontier and declare that [nearby] space was "bunk". America's most influential astrophysicists meanwhile were not so confident. Thus it was not until the 1960's they were able to persuade NASA to give up their fundamental in situ measurement of nearby space and their part in any 1986 rendezvous with Comet Halley in order to concentrate on the cosmic arena beyond. As a consequence, although the first rendezvous with a comet quickly firmed up the best (post-war) model for comets and the in situ measurement of nearby space rapidly established the particulate outflow of cisJovian space which laid bare the giant comet debris producing zodiacal dust, the perceived official position of astrophysicists in Western civilization is still one in which those who belong to "the cosmic arena" are expected to keep apocalypticism at bay. It is easy to understand, therefore, why many astrophysicists were provoked by the writings of Velikovsky [78, 79] who, as a psychoanalyst, was justifiably very interested in the origins of apocalypticism but who unfortunately laid himself open to easy condemnation through his advocacy of an irrelevant and certainly inadequate "planetary" theory for some past comets. Normally, of course, astrophysicists would display some forbearance in the presence of theoretical inadequacies of this kind but, in this case, it was all too obvious that they had failed to address the historical evidence for apocalypticism and were merely intent on creating a cover for their own deficiencies. Whipple , on the other hand, did not address apocalypticism but did nevertheless introduce the first realistic theory of subcometary debris for nearby space involving a recent giant comet and this was widely approved by comet scientists 147]. Clube and Napier [21, 22] then developed this theory in the longer term galactic/geological context in such a way as to permit the issue of apocalypticism to be specifically addressed [1, 2, 17]. Very few astrophysicists now seem anxious to defend the English bishops although those hoping to eliminate apocalypticism from the course of classical medieval and modern history [13, 58] still continue to express themselves rather vehemently. The inner Solar System is dominated by apparently two distinct "bombardments" from the cometary cloud that accompanies the Sun in its orbit around the Galaxy . One of these is essentially an "unevolved" bombardment which has undergone little or no interaction with the Sun and planets: it mostly comprises ordinary comets in orbits whose semi-major axes are relatively large and whose perihelia are isotropically distributed, implying a high mean ecliptic latitude (i.e. a population made up of so called Halley-types ). The other is essentially an "evolved" bombardment which has undergone considerable physical and dynamical interaction with the Sun and the planets: it mostly comprises the sub-cometary debris of giant comets in orbits whose semi-major axes are relatively small and whose perihelia generally lie close to the ecliptic, implying a low mean ecliptic latitude (i.e. a population made up of so called Encketypes). The dynamical histories of these bombardments are such that the Halley-types evidently sample the direct influx of comets perturbed from the so called inner Oort cloud. This influx is periodic (~26 myr) in accordance with the cloud's probable penetration by impulsive perturbers in the form of low velocity dark matter from the nearby mainstream circulation of the Galactic disk. The Encketypes on the other hand appear to sample the indirect influx comets perturbed from the inner Oort cloud which first settle in the outer Oort cloud and then preferentially transfer, in the case of objects that ultimately settle in the inner Solar System, to "sungrazing"/"Jupiter-avoiding" orbital configurations whose mean motion is resonant (e.g. 7: 2 J, mean period = 3.39 years) and whose initial perihelion direction is in the general vicinity of Jupiter's. The perturba-tion flux in this instance reaching the Earth is likely to be triply periodic in accordance with the Sun's distance from the Galactic plane (~26 myr but 90° out of phase with the direct perturba-tion flux), the outer Oort cloud's perihelion distribution with respect to precession of the Jovian longitude of perihelion (~79 kyr) and the sungrazer nodal precession (~2.5 kyr) in relation to the Earth's orbit . The physical characteristics of these direct and indirect perturbation fluxes are however fundamentally different. The Halley-types reaching the Earth are essentially dominated by the commonest inner Oort cloud comets. that is, by ordinary small comets with velocities close to the Solar System velocity of escape at the Earth's orbit. The Encketypes reaching the Earth are essentially dominated by the sub-cometary fragments originating from the rarest and largest inner Oort cloud comets, that is, by the meteoroid fragments of giant comets with velocities much closer to the velocity of circulation at the Earth's orbit. For a representative linear size ratio between small comets and meteoroid fragments of 10, the impact energy ratio is~10,000 resulting in qualitatively different effects on the Earth. The direct perturbation flux essentially reaches the surface of the Earth and is responsible for craters, mass extinctions and major geological effects, the indirect perturbation flux, on the other hand, essentially reaches only the atmosphere producing impact fireballs and disintegration dust-veils, the latter primarily affecting the climate and the magnetic field. These general predictions are well illustrated by the differing mass extinction and geomagnetic reversal patterns of the late Phanerozoic respectively . The current location of the Sun in the Milky Way, very close to the Galactic plane, implies the Earth is currently half way between the preceding and forthcoming mass extinction "bombardments" 26 myr apart but more or less within a major glaciation "bombardment". The latter bombardment is itself apparently cyclic with a sub-periodicity of~79 kyr whose peaks roughly correspond to the most recent giant comets settling in inner Solar System space, the latest being responsible therefore for the last glacial starting~60 kyr BP. The size and orbital con-figuration of giant comet sungrazers imply glacials that last~50 kyr and the present overall pic-ture is therefore consistent with a current giant comet which is likely to have reached the end of its physical and dynamical lifetime within (say) the last 10-5 kyr. The most recent glacial-0-10 kyr BP is evidently in broad agreement therefore with this astronomical prediction and would lead us to expect a huge remnant "doughnut" of zodiacal dust (bounded by ecliptic latitude bands) where the sungrazing progenitor's original meteoroid stream has interacted with the as-teroid belt and, in addition, another more substantial meteoroid stream resulting from a terminal encounter of the highly evolved progenitor with one of the inner planets (involving its complete tidal disintegration a la ShoemakerLevy). Such a doughnut was first detected in modern times by the Infra Red Astronomical Satellite in 1983 and, although an original sungrazing meteoroid stream has yet to be discovered, is highly suggestive of the much earlier more luminous, "boundary" configuration ("flaming walls" and "narrow bridge") which was such a prominent feature of gnostic cosmology. It follows that the "Taurid" meteoroid stream is very likely to have been formed as a result of a close encounter with an inner planet producing a complex of progenitor debris whose central core is also likely to be closely associated with the 7 : 2 J resonance. Substantial evidence now exists in fact for a general category of inner Solar System disruptions associated with the Taurid Complex involving devolatilised cometary bodies which provide the bulk of the fragile material reaching the Earth since ca 5000 BP [1, 2, 3, 17]. The general dynanucal characteristics of the Taurid Complex are notably consistent with its formation some 5000 years ago in association with an initial luminous trail of the disrupted progenitor as the latter underwent gravitational deflection during its "terminal" close encounter with an inner planet (specifically in accordance with a cross at a low point of the narrow bridge). Apart from the relationship between this Complex and the generally random apocalyptic process discussed in the Sections above, the nodal precession of the Taurid progenitor is of particular significance since it results in an overriding long-term~2.5 kyr "global cooling"f'global warming" cosmic dust cycle on Earth as well as the correlated "Dark Age"/"enlightenment" bombardment cycle particularly affecting mankind. Strictly speaking the~2.5 kyr dust bombardment cycle is a~5.0 kyr double cycle with alternating phases depending on the Taurid stream aspect with respect to the terrestrial polar axis (which is itself subject to a much slower precession)-see Figure 1. It is of interest therefore that the latest geophysical investigation of the pervasive "millennial-scale" cycle in the Holocene and Late Upper Pleistocene climate (i.e. since~60 kyr BP) based on deep ocean sediment records of ice-rafting events in the North Atlantic  clearly indicates a dominant~4.7 kyr cycle which is likely nevertheless, in view of the more detailed~2.5 kyr cycle of the Holocene , to be a precessional double-cycle confirming the underlying role of the Taurid giant comet source. Of particular significance in this study is the additional existence of a more random "cycle" of 1.47~0.50 kyr associated with sudden cooling events which evidently persist into the Holocene and which therefore bear witness to a continued interaction with the Earth involving unexpected but comparatively major apocalyptic events.
NODAL PRECESSION OF TAURID NODAL STREAM
Figure 1: Illustration showing typical nodal precession for the core of the Taurid stream, in particular when the Earth's orbit is intersected (note the arrows). The parts of the orbit respectively above and below the ecliptic are shown as thick and thin lines, The tirnescale is t(AD). The Earth intersection epochs evidently occur ca 2200-2000 BC and ca 300-500 AD (implying a bombardment/dust cycle of around 2.5 kyr) while the corresponding perihelion positions are below and above the ecliptic
It has been shown here that the approximately centennial rise and fall of fireball streaming sometimes associated with Earth-approaching comets or asteroids is also the historical source of apocalyptic "signs". This streaming is a proxy for hazardous swarms of sub-cometary debris representing a higher flux to Earth than normally conceded of bodies in the mass range~10 12 -10 15 g. Largely overlooked since early modern historical time (and even flatly proscribed by some authorities 113, 58]), this hazard appears most commonly to take the form of global climatic recessions, involving high-level dust albeit low-level multi-megaton explosions associated with the most robust debris are by no means excluded. These recessions are a feature of the general flow of "Taurid" material to Earth recorded in polar ice-cores and ocean sediment-cores, now recognized as being responsible for a basic 5000 year doublecycle alternately producing global warming and global cooling. During the course of the Enlightenment, mankind has singularly failed to come to terms with this apparently centennial threat, having become strangely preoccupied during the Space Age with a very much less frequent threat (roughly a thousand times less frequent!) which is directly due to comets and asteroids. Whether or not mankind recognizes the approximately centennial threat is tantamount to choosing between apocalyptic and antiapocalyptic outlooks on the environment. This question as I have shown, is of deep historical and political significance being intimately bound up with the origins of Christian doctrine and with the elitist desire to perpetuate anti-apocalypticism along with its appropriately distorted cosmological setting. In view of the intellectual and cultural climate of irrationality which arises thereby, it is a moot point whether mankind will meet the challenge posed by this question before the next bout of apocalyptic terror descends. Such a situation represents an intolerable risk to civilization.
I would like to thank Dr David Asher, Dr Alan Edwards and Dr Benny Peiser for critical comments on an earlier draft of this review, also the Society for Interdisciplinary Studies for the invitation to speak at Cambridge and the Leverhulme Trust for material support.
1. Asher, D. J. & Clube, S. V. M. 1993 Q. J. R. Astron. Soc. 34, 481
2. Asher, D. J. & Clube, S. V. M. 1998 CeL Mech., in press
3. Asher, D. J. & lzutni, K. 1998 Mon Not . R. Astron. Soc 297, 23
4. Astapovic, I. S. & Terenteva, A. K. 1968 Physics and Dynamics of Meteors eds. Kresak, L. & Millman, P. (Reidel, Dordrecht), 308
5. Bailey, M. E.,, Clube, S. V. M. & Napier, W. M. 1990 The Origin of Comets (Pergamon)
6. Bailey, M. E., Clube, S. V. M., Hahn, G., Napier, W.M. & Valsecchi, G.B. 1994 In: Hazards due to Comets and Asteroids ed. Gehrels, T. (University of Arizona Press, Tucson), 479
7. Barb, A. A. 1963 In: The Conflict between Paganism and Christianity in the fourth Century ed. Momigliano, A. (Clarendon Press, Oxford), 100
8. Barnett, S. J. 1997 In: Prophecy eds. Taithe, B. & Thornton, T. (Sutton Publishing), 101
9. Binney, J. & Tremaine, S. 1987 Galachc Dynamics (Princeton University Press)
10. Biot, E. 1807 Mern. Acad. Sci. Inst. Nat. France 10, 129
11. Bond, G., Showers, W., Cheseby, M., Lotti, R., Almasi, P., Menocal, P. de., Priore, P., Cullen, H., Hajdas, I., & Bonani, G. 1997 Science 278, 1257
12. Bultmann, R. 1957 History and Eschatology (Edinburgh University Press)
13. Chapman, C. R. 1998 The Asteroid/Comet Impact Hazard (draft)
14. Chereul, E., Creze, M. & Bienayme, O. 1998 Astron & Astrophys,~n press
15. Christianson G. E. 1984 In the Presence of the Creator: Isaac Newton and his Times (Free Press)
16. Clark, J. C. D. 1985 English Society 1688 -1832 (Cambridge University Press)
17. Clube, S. V. M. 1995 Vistas in Astron. 39, 673 18. Clube, S. V. M. 1994 Fronhers of Fundamental Physics eds Barone, M. & Selleri, F. (Plenum), 107
19. Clube, S. V. M. & Napier, W. M. 1984 Mon.Not. R Astron. Soc. 211, 953
20. Clube, S. V. M. & Napier W. M. 1986 In: The Galaxy and the Solar System eds. Smoiuchowski R. et al (University of Arizona Press, Tucson), 260
21. Clube, S. V. M. & Napier, W. M. 1990 The Cosmic Winte (Basil Blackwell, Oxford)
22. Clube, S. V. M. & Napier, W. M. 1996 Q. J. R. Astron. Soc. 37, 617
23. Cohn, N. 1957 The Pursuit of the Millennium (Seeker & Warburg, London)
24. Cohn, N. 1993 Cosmos, Chaos and the World to come (Yale University, New Haven & London)
25. Corcoran, T. H. 1971 (translator) Seneca: Naturales Queshones (Heinemann, London)
26. Darwin, C. 1872 The Origin of Species (John Murray, London)
27. Dawson, C. 1972 The Gods of Revolution (Sidgwick & Jackson)
28. Dempster, W. J. 1996 Evolahonary Concepts in the Nineteenth Century (Pentland Press)
29. Eddington, A. S. 1931 Mon. Not. R. Astron. Soc. 91, 412
30. Eggen, O. J. 1965 Galactic Structure eds Blaauw, A. & Schmidt, M. (University of Chicago Press), 111
31. Esmonde Cleary, A. S. 1989 The Ending of Roman Britain (Batsford, London)
32. Farrington, B. 1944 Greek Science (Pengu~n)
33. Fechtig, H. 1982 In: Comets ed. Wilkening, L. (University of Arizona Press, Tucson), 370
34. Frankfort, H. 1948 Kingship and the Gods (University of Chicago Press)
35. Gehrels, T. 1994 (editor) Hazards due to Comets and Asteroids (University of Arizona Press, Tucson), 370
36. Gibbon, E. 1776 The Decline and Fall of the Roman Empire ed. Low, D. M. (Guild Publishing, London)
37. Gibson, K. 1997 In: Prophecy eds. Taithe, B. & Thornton, T. (Sutton Publishing), 71
38. Goldstone, J. A. 1990 Revolahon and Rebellion in the Early Modern World (University of California Press)
39. Hill, C. 1975 Change and Condnuity in Seventeenth Century England (We idenfeld & Ni co l son)
40. Hitchin, N. W. 1995 Anglican Theological Review 77, 394
41. Hitchin, N. W. 1997 In: Prophecy eds. Taithe, B. & Thornton T. (Sutton Publishing), 119
42. Hoyle, F. & Wickramasinghe, C. 1985 Liv'ing Comets (University College Cardiff Press)
43. Huxley, T. H. 1931 Lectures and Essays (Watts & CO, London)
44. Huxley, J. 1941 Religion without Revelation (Watts & CO, London)
45. Kerr, F. J., & Westerhout, G. 1965 Galactic Structure eds. Blaauw, A. & Schmidt, M. (University of Chicago Press), 167
46. Keynes, J. M. 1946 The Royal Society Newton Tercentenary Celebrahons (Cambridge University Press), 27
47. Kresak, L. 1980 Solid Particles in the Solar System eds. Halliday, I. & McIntosh, B. A. (Reidel, Dordrecht), 211
48. Lamarck J. B.1809 Zoological Philosophy trans. Elliot, H. E. (Macrnilian, London)
49. Lamb, H. H. 1977 Climate: Present, Past and Funure (Methuen, London)
50. Lamont, W. 1996 Puritanism and Historical Controversy (University College London Press)
51. Lee, H. D. P. 1971 (translator) Plato:Timaeus and Crihas (Penguin, London)
52. Lewis, J. 1954 Introduch'on to Philosophy (Watts & CO, London)
53. Lyell, C. 1832 The Principles of Geology (John Murray, London)
54. Matese, J. & Whitmire, D. 1996 Astrophys. J. Lett., preprint
55. Matthew, P. 1831 Naval Timber and Arboriculnure (Longman et al, London)
56. McDermott, T. 1989 (translator) Aquinas: Summa Theologiae (Methuen, London)
57. Morrison, D. 1992 (chair) The Spaceguard Survey: Report of the NASA Internahonal Near-Earth- Object Detechon Workshop
58. Morrison, D. 1997 Skephcal Inquirer 354, 22
59. Napier, W. M. 1994 Fronhers of Fundamental Physics eds Barone, M. & Selleri, F. (Plenum), 13
60. Napier, W. M. & Clube, S. V. M. 1997 Rep. Prog. Phys. 6O, 293
61. Neugebauer, O. 1945 Jour. Near East. Saud. 4, 1
62. Newton, I. 1733 Observahons upon the Prophecies of Daniel and the Apocalypse of St John (Derby, J. & Browne, T., London)
63. Oí Brien, S. R., Mayewski, P. A., Meeker, L. D., Meese, D. A., Twickler, M. S. & Whitlow, S. 1. 1995 Science 27O, 1962
64. Oort, J. H. 1950 Bull. Astron. Inst. Neth. 11, 91
65. Paley, E. 1823 An Account of the f if e and Wridngs of William Paley, Works (London)
66. Sherlock, T. 1724 The Use and Intent of Prophecy, in the several Ages of the World (Pernberton, J. & J., London)
67. Spearman, R. 1755 An Abstract from the Works of John Hutchinson (Withers, E., London)
68. Spengler, O. 1932 The Decline of the West ed. Hughes, H. S. (Oxford University Press)
69. Sprat, B. T. 1665 History of the Royal Society ed. Cope, J. I. & Jones, H. W. (St Louis 1959)
70. Steel, D. I., Asher, D. J., Napier, W. M., & Clube, S. V. M. 1994 In: Hazards due to Comets and Asteroids ed. Gehrels, T. (University of Arizona Press, Tucson), 463
71. Stone, L. & Fawtier Stone, J. C. 1984 An Open Elite (Oxford University Press)
72. Taithe, B. & Thornton, T. 1997 (editors) Prophecy (Sutton Publishing)
73. Thomas, K. 1971 Religion and the Decline of Magic (Weidenfeld & Nicholson)
74. Thompson, D. 1996 The End of Time (Sinclair-Stephenson)
75. Toynbee, A. J. 1945 A Study in History (Oxford University Press)
76. Trevor-Roper, H. 1987 Catholics, Anglicans and Puritans (Seeker & Warburg, London)
77. Van der Waerden, B. L. 1974 Science Awakening 11: the Birth of Astronomy (Noordhof In-ternational Publishers, Leiden)
78. Velikovsky, I. 1950 Worlds in Collision (Victor Gollanz, London)
79. Velikovsky, I. 1982 Mankind in Amnesia (Sidgewick & Jackson, London)
80. Walker, B. 1983 Gnosticism (Crucible)
81. Whipple, F. L. 1967 NASA SP-150, 409
82. Woolf, N. J. 1995 Vistas in Astron. 39, 699