Before the Pyramids: Cracking Archaeology's Greatest Mystery (10 page)

Whilst we have been very critical of the general direction that archaeology has taken over recent years, there is no doubt that a tremendous amount of good work has been done at a technical level – and occasionally on an inspirational level as well. One archaeologist has made a rather guarded suggestion that the existence of the Thornborough henges may have had something to do with astronomy. Dr Jan Harding from Newcastle University has put forward the idea that the dogleg layout of the henges may be present because the builders wanted to construct the henges in a formation that copied the three stars we know as Orion’s Belt. And furthermore perhaps the nearby River Ouse was likened to the Milky Way.

When we first read this we thought it was a bit of a wild guess – possibly secretly inspired by Robert Bauval’s similar claim for the Giza pyramids. Whilst Bauval had a number of cultural as well as artefact-based reasons for his Orion claim in Egypt, there seemed to be nothing more than a similarity of shape at Thornborough. However, a check of the relative positions of the stars and the henges provided a near perfect fit (
see
figure 9).

Having found a raft of reasons to link these henges with the stars, we began to feel a great deal more sympathy with Harding’s suggestion and we started to investigate possible usage of the site in connection to Orion’s Belt and Sirius – to which this star group points.

The bank tops of the Thornborough henges formed an unchanging artificial horizon. When any planet or star appeared over a bank top it did so at exactly the same altitude as any other planet or star. This is not the normal state of affairs in an undulating landscape. (
See
figure 10.) As long as the bank tops are even, and also take account of the very slight slope upon which the henges were built, the scene is set for the most perfect form of naked-eye astronomical observatory possible.

One of the most important prerequisites for a successful series of experiments is to make sure that the circumstances under which they are carried out remain the same. This requirement was catered for perfectly by the giant henges of Thornborough and Dorchester-on-Thames. It is also clear that for experimental astronomy the use of stones, such as those to be found at Stonehenge and other circles, would be inefficient and totally inappropriate. Markers could be used at the super-henges and undoubtedly were, but these would have been wooden poles, dug into the soil just beyond the bank tops wherever they proved to be necessary. These could be ‘tweaked’ or removed altogether if necessary and placed somewhere completely different. It would have been relatively easy to move such poles around to wherever they were needed. Instructions from the centre of the henge, which was the ‘eyepiece’ of the naked-eye telescope, would allow helpers beyond the banks to do what was necessary to ensure that marker poles occupied ‘exactly’ the right spot.

Figure 9.
Thornborough henges with Orion’s Belt superimposed

Stars will rise at different times across
an undulating horizon, making useful
experiments difficult or impossible.

Figure 10.
Stars rising on an undulating horizon

Day after day, night after night, probably for centuries, specifically trained people would refine their knowledge of astronomy, maintain the ritual and agricultural calendars, and fix the date of special celebrations or events from their observations within the henges. So, what sort of observations could be undertaken utilizing the henges? The answer is – a multitude.

Observers within the henges could track the position of the rising Sun throughout the year, marking its northerly and southerly movement with the seasons. They could ‘fix’ the points of the Sun’s extreme positions in the midsummer and midwinter by use of marker poles. We know from lunar calendars carved onto antlers and bones from a very early period that humanity has always been fascinated by the strange and difficult-to-assess behaviour of the Moon. The Moon could have been studied for decades from the henges. Observers would eventually realize that its movements, in a monthly sense, mirror those of the Sun in its yearly behaviour. They would also pick up on more complicated lunar rhythms, such as the ‘Saros cycle’. The Saros cycle can be judged from lunar movement across a long period of time and is a combination of different types of lunar month that can be used to predict the occurrence of solar and lunar eclipses.

The observatories at Thornborough and at other henges could also be used to track the rising and setting points of both planets and stars. In the case of planets a better understanding of their sometimes tortuous movements would be gained, and absolute values for their periods could be established. Because planets are nearby objects that orbit the Sun, on more or less the same plane as the Earth, they appear to have highly complex movements. The stars are many light years, sometimes millions, further away than any planet and so they rise and set in the same place on the horizon for long periods of time – but not indefinitely.

There is a phenomenon all astronomers understand that is known as the precession of the equinoxes, and anyone using the giant henges as observatories across a long period of time could not have failed to notice its effect. Precession comes about as a result of secondary movements of the Earth. In addition to turning on its axis, and orbiting the Sun, the Earth has other, long-term movements. One of these is a tendency to behave somewhat like a child’s spinning top, which in addition to spinning, also ‘wobbles’ on its axis (
see
figure 11). One whole wobble takes a very long period of time in human terms (approximately 26,000 years). From the point of view of an earthbound observer the effect would be that, very gradually, stars would change their rising and setting points on the horizon. Even a couple of human generations would see stars altering their rising and setting points by a full degree, and so long-term observation would betray the existence of precession to the astronomer henge builders.

This last example offers a perfect explanation for the henges being so large. We would judge the gradual movement of a rising star on the horizon these days with advanced optical instruments. Telescopes make very small things look very big and, if they are fitted with crosshairs and measuring dials, they can be used to measure very small increments. The naked eye of a human being is far less sophisticated in terms of its ability to discriminate a small gap at a great distance. The best way to compensate for this inadequacy is to somehow ‘make’ the gap in question bigger. How can this be achieved? The answer is by looking out at the largest circle possible. In the case of naked-eye astronomy the true horizon is best, but it undulates and it is also sometimes difficult to see stars rising on the horizon because of atmospheric anomalies.

The Earth does not simply spin on its axis (A).
It also spins about its poles like a top (B).

Figure 11.
Earth precession of the equinoxes

A very small henge might work reasonably well for some observational purposes but there would be a greater opportunity for error. If you wanted a really good scientifically accurate observatory you would want it to be very large, but not so big that you could not shout instructions from the centre. A perfect size would be the Thornborough trio. A series of straight poles driven into the earth just beyond the bank top would appear to be the finest of lines when seen from the centre of the henge. At night such a pole would not be seen at all, but what ‘would’ be seen would be the instant appearance of a star or planet that had just passed behind a first pole, which could then be timed until it appeared from behind a second pole placed 2 MY away in line with the star’s trajectory. Using a pendulum for timing the star produces split-second results.

Most archaeologists, and even some experts in the field of astroarchaeology, which is the study of ancient astronomy, would accept that there are great limitations to what could be expected of naked-eye astronomy. In a sense this is true because of the nature of human vision when compared with accurate telescopes. But we have already shown in our book
Civilization One
that there is another factor involved that is often either forgotten or not fully understood. This is an ability to measure the passage of time accurately, without which any form of astronomy is bound to be extremely limited in its possibilities. The best telescope in the world would be virtually useless in an astronomical sense if it were not allied to an accurate clock.

The three super-henges at Thornborough did not stand alone in the Stone Age landscape of North Yorkshire. Other super-henges have been noted around them. Some of these have only been detected since the advent of aircraft because they have been so degraded by weathering and ploughing that they now represent little more than ‘parch marks’ in the landscape. There are in fact no less than six large henges altogether in this part of the world, and their presence in so small an area tends to add to the feeling that this area of Britain was considered in some way very special by those who laboured to dig the ditches and throw up the banks.

Dr Jan Harding is in no doubt that a religious imperative underlies the astronomical possibilities of the henges. We can accept that this may be true in part, but it must not obscure the excellence of the science involved. The study of astronomy, which is a purely scientific endeavour, is considered to be a recent innovation. Human beings all over the globe have been looking at the heavens for countless generations, but only around the 18th century did some investigators begin to abandon the notion of heavenly movements being associated with religion and fate. Before that time, and even today, for millions of people around the world, the patterns of stars to be seen in the sky and the complicated interplay formed by the Sun, Moon and the planets could be viewed as portents of future events. This is the study of astrology, and though modern astronomers get extremely agitated when the word astrology is mentioned, it is interesting to note that one of their greatest heroes, Sir Isaac Newton, spent far more of his life studying astrology than he did astronomy or physics.

To our ancient ancestors the sky, and especially the night sky, must have been a thing of wonder and, as we will discuss later, dread. Its significance is lost to us these days for a number of reasons but the greatest amongst these is light pollution. Most people in industrialized nations now live in an urban setting, surrounded by artificial lights of all kinds. This makes viewing the stars much more difficult. If any readers want to gain some appreciation of the way our ancient ancestors saw the night sky they will need to take themselves to some very isolated spot on a clear, crisp night, preferably when there is no Moon. The broad sweep of the Milky Way across the heavens, the panoply of stars and the apparent patterns created by the brightest and most magnificent of them all, form an awe-inspiring sight, even to those of us brought up to understand what planets and stars actually are. However, one star is brighter than all the others. This star is Sirius and it appears to have been of the most crucial importance to our species, both astronomically and astrologically, since the dawn of human awareness.