Stonehenge: What happens when Astronomy and Geometry are denied. Fed up of watching programmes about Stonehenge that take up to an hour to inform the viewer of all the things Stonehenge isn’t? Would you really like to know something about how this stalemate concerning our National Temple has come about? Well, read on. In September 1999, a consultation draft was issued by the Stonehenge World Heritage Management Plan, prepared by the renowned environmental architect Chris Blandford. 110 pages in length, this draft contains but a single paragraph (2.4.12) of just 9 lines that makes an attempt to cover the astronomy of the monument. ‘While theories about the reasons for its construction, the manner of its use and its role as a sacred place abound, these can be but speculation. (my italics). There is no attempt to cover the geometrical design of the monument and nor does the author identify just who suggests that theories on the monument are ‘but speculation.’ This consultation draft represents the official ‘take’ on Stonehenge. It may prove to be a most useful document in flowing visitors in and out of the site, and may prove invaluable in getting traffic disturbance removed, but clearly it ain’t ever going to address the astronomy and geometry of Stonehenge, two facets of the monument that are hardly speculative, for both can and have been objectively measured and calculated by many people, from the father of modern archaeology, Flinders Petrie, to the foremost specialist on Stonehenge, Prof Richard Atkinson. Sir Norman Lockyer determined the accuracy and assessed the midsummer axis in 1901. The monument has been exquisitely accurately surveyed ( for the first time) by Prof Alexander Thom under the watchful eye and cooperative assistance of Atkinson (1973). Something is being avoided one feels, and here’s what it is. Of all the most remarkable facts to emerge from the distant past, the most striking is that the astronomers of various civilisations had discovered methods whereby they might define accurate calendars and predict eclipses in advance. Theories differ as to the purposes to which this powerful knowledge was applied, but the background of observation, study and formulation of the techniques required to predict the date, time and the type of eclipse, solar or lunar, was admirably established before 2000 BC. That this information may have been used to control the masses by appearing to be controlled by astronomer-priests is less important here than the fact that the required science was in place and clearly working so early in our recorded history. To predict eclipses, a great deal of understanding of the celestial motions of the sun, moon and earth is required. Included in this knowledge is the concept of the ecliptic, that invisible line across the sky that the Sun appears to track along, a huge ring encircling the earth which represents the path of the sun during the year. It is also necessary to know the length of the year to high accuracy, and how the moon moves around the earth, the time it takes not only to return to the same place in the sky but also to complete one cycle of its monthly phases. The former is now called the sidereal (star) month, and is 27.32166 days in duration, the latter the lunation cycle, 29.53059 days, the difference being caused by the earth having moved in its orbit during the month such that the required alignment between sun, moon and earth to reform a new moon or a full moon takes an extra 2.09 days each month. Observation of these motions against the fixed stars of the revolving firmament quickly establishes that the alignment of sun, moon and earth at each new moon, or sun, earth, moon at each full moon, does not produce a solar or lunar eclipse. Only sometimes does a lunar eclipse take place, on average one a year at any given location, and only very rarely is a solar eclipse seen at a given location, owing to the narrow cone of shadow produced by the moon intervening between the sun and the earth. To discover which full or which new moon will produce an eclipse requires a study of the pattern of eclipses over many years. How the ancients undertook such an observational study is unknown, but it evidently represented a high pinnacle of knowledge for many cultures, zenith of astronomical knowledge. What is remarkable is that there is so much evidence left on the ground that can still enable the prediction to be made simply, once that observational phase is over and the time periods known. Once the numbers of the sun’s (apparent) orbit of the earth and the moon’s monthly periods is known, simple techniques exist to simplify and shortcut the complications such that almost anyone can make the predictions. These techniques are covered on Sky and Landscape courses, and the techniques may be identified within some of my books. They are essentially geometrical techniques and some of them may be found at Stonehenge, where the 56 marker Aubrey circle is potentially the oldest known calendar and eclipse predictor. While it is impossible to ever confirm that this 5000 year old construction was ever used for such purposes, the truth remains that it is the most perfect circular device for bringing the motions of the sun and earth down onto the earth, for drawing down the moon and for predicting eclipses, full and new moons and a host of other important calendrical information. Asked by Cambridge archaeologist and Antiquity Editor Dr Glyn Daniels to assess the new Gerald Hawkins book, Stonehenge Decoded (1965), the most influential astronomer of the post-war period, Professor Fred Hoyle, quickly assessed the Aubrey holes as the basis for an analogue ‘clock/calendar showing the positions of sun, moon and lunar nodes – and hence eclipse prediction'. Daniels was not a happy man at this outcome, he was keen to deal Hawkins’ work a death blow in the review. From Hoyle he got more than he bargained for – Hoyle saw immediately how those 56-holes uniquely stitched up the motions of the Sun, Moon and eclipse patterns. No other number would have done it! This device still is capable of working as it may once have been worked. Other circumstantial evidence for the use of the ‘Aubrey device’ supports the hypothesis that it was so used, as Greek sources link the god Typhon with both eclipses and the number 56, and Stonehenge does appear to have been built with much knowledge of the sun and moon built into its various stages. Let’s look at some of these. They are not hard to discover, nor are they astronomically abstruse. For example, the 19 slender polished bluestones forming the innermost horseshoe may be taken to represent the 19 year Metonic repeat cycle of the sun and moon, a most important calendrical cycle and almost certainly that one referred to by Diodorus in his quotation about the inhabitants of the hyperborean island where a circular (spherical) temple dedicated to Apollo (the sun god) may be found and where the priesthood await the sky’s return every nineteen years. Further, the sarsen circle at Stonehenge once contained thirty upright stones carefully arranged into a circle upon which a level platform of thirty interlocked lintels was placed. One of the upright stones, number 11 going clockwise from the midsummer axis line along the Avenue, an axis which itself is an indication of astronomical intent, is half the width of the rest, numerically suggesting 29 and a half, the length of the lunation in days. Furthermore, this stone is placed 7/19ths along the perimeter from the axis of the whole monument, and 7/19th is the disparity or surplus in lunations between 12 lunar months (354.37 days) and the solar year (365.242 days). Any attempt to understand the soli-lunar calendar would have to involve this fraction. Finally, the four stations stones once defined, according to Aubrey Burl, a ‘near perfect rectangle’ whose short sides aligned to the midsummer sunrise and midwinter sunset positions while the long sides aligned to the vital standstill position of the moon on the horizon, a position one must know to predict eclipses accurately. Only close to the latitude of Stonehenge can a rectangle be employed to do this, making the location of Stonehenge astronomically significant. This rectangle is dimensioned as a 5:12 ratio, in units of 8 Megalithic yards (MYs). The diagonal thus becomes 13 of the same units, or 104 MY. The 5:12:13 triangle enables an accurate soli-lunar calendar to be constructed simply, and it predicts type and date of eclipses. So there are plenty of reasons to support a calendrical, and hence astronomic component to Stonehenge’s design. In each case, the geometry of the monument supports the astronomy. No one fully understands the significance that drove the architects and builders, at such vast expense of toil, to construct this mammoth temple to Apollo on Salisbury Plain, but at least some of this can reasonably be attributed to an astronomical function, even to the actual latitude chosen, and how was this discovered, then? So how is it that the orthodox view of Stonehenge makes so little of any astronomical or geometrical properties of the monument, why is nearly every single program made by the media on Stonehenge leaving its audience numb with boredom? It is almost as if we are told that the monument built itself and has nothing at all to say to us, while ‘experts’ are wheeled in to wax lyrical about religious rites and tribal meetings, and the impressive fact that such large stones were placed so accurately into position (without ever showing how that was done in solid stone, rather than polystyrene replicas). We never find anything out, never pass through the subjective opinions of our experts! There is never an attempt to answer the really big questions. Like: Why is Stonehenge built where it is? 12 million man-hours spent building a temple on a whimsically decided site – nah!. Why were the bluestones so important to the project - why were these lovely stones lugged from West Wales, surely a question worth a stab at? Finally, why was Stonehenge built at all? It’s unique, it’s massive and orthodox thinking hasn’t a clue why it was built nor why it is located where it is. Nor what it was for. Our orthodoxy has failed us. Why? Well, that’s another most interesting journey, for another website entry. Summary Stonehenge & The Bluestone Site - Key Questions 1. Why was Stonehenge built? 2. Why was it located where it is? 3.Why were the bluestones so important as to engender lugging 80 of them from Preseli to Stonehenge? In 250 years, archaeologists have not been able to answer any of these questions. They have been remarkably slow to discover the obvious astronomical and geometrical features built into the monument and into its relationship with the Preseli site. ASTRONOMY. The Avenue is aligned to Midsummer sunrise. Heel Stone is called Friar’s Heel in old books and on old plans. There’s a quaint myth concerning a friar planting his hoof-print on the stone. More obviously credible as the origin for the name of this stone, Ffriw yr Haul is Welsh for the ascending of the Sun, pronounced Friar Heel. Sorted! Station stones are aligned on their shorter side to Midsummer sunrise, along the longer side to maximum northerly moonset every 18.618 years. The three recently (1965) discovered and horribly named ‘Car Park Post Holes’ sit firmly on the alignment to the most northerly moonset at the major standstill, as seen from Stonehenge. The 56 Aubrey Holes can be used to make a simple Sun/Moon position recorder and hence a calendar. This same number also allows eclipses to be forecast in advance. Astronomer Prof Sir Fred Hoyle first spotted this unique numerical relationship in 1964. The diameter of the sarsen circle to the Aubrey circle (the two main circles at Stonehenge) form the ratio 7/19, the fraction of a lunar cycle left after 12 lunar months and the end of a (solar) year of 365.25 days. This fraction has to be known to understand how to design soli-lunar calendars. The station stones form a 5:12 rectangle, the basis of a lunation triangle from which calendars and eclipses can be understood. The station stone rectangle is 5:12 in units of 8 Megalithic yards. The 5:12 rectangle between Stonehenge, Lundy and the Preseli site is exactly 2,500 times larger than the station stone rectangle, and has sides of 100,000 and 240,000 MY. If the Megalithic yard is assumed to represent the lunar month, then precisely one foot represents the over-run between lunar and solar year (354.357 and 365.242 days) GEOMETRY A seven-sided star neatly connects the Aubrey circle (283 feet) with the later sarsen circle. The inner star arms cross at the mean diameter of the sarsen circle. The station stone rectangle forms four points of an octagon. METROLOGY The inner and outer sarsen ring diameters are 97.32 and 104.27 feet. This is 28 and 30 Royal yards (double Egyptian royal cubits of 1.737 feet) A Royal yard is one six millionth of the polar radius Stonehenge is exactly one quarter of a degree of latitude from Avebury - 17.28 miles And so on…a seamless catalogue of interconnecting design rules all integrated to each other. Speculative? Or proof of a cultural intent that is quite astonishing – a heritage gold for Britain. Instead of being understood as a rather badly sited pile of impressively large stones, Stonehenge can become something else – the zenith of neolithic astronomy and stone age culture. And we all look forward to some stonkingly interesting TV doccies about Stonehenge in the future. That should pack the tourists in! Copyright Bluestone Press 2005. All rights reserved by the author.