Precession and The Sun.

The reason I began this blog was my fascination with a timber circle close to Avebury, known as The Sanctuary.

Just arrived at Sanctuary. 

Though it may have been  originally constructed in the late Neolithic period, it was re-configured with the addition of standing stones during the Bronze Age, around the time Silbury Hill was being heaped up (something like 2400 BC).

Silbury.

During the same time period, Sarcen stones were dragged from Fyfeild  to create the stone circles within Avebury and  its avenues; one of which connects Avebury to the Sanctuary.

More stone was used to block off the already ancient long barrow of West Kennet, to prevent any access either in or out possibly indicating that the old places of the dead were no longer connected with the living.

The Long Barrow of West Kennet, is a thousand years older than the Sarcen avenues and circles.


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Kennet Avenue, leading towards Avebury.

The Sanctuary -once a timber sircle - seems to have been closed off to some extent by the addition of stones, but it was also linked and included with Avebury via a stone lined avenue -a wide procession of stone you can still walk along closer to Avebury.

Once upon a time The Sanctuary was a set of wooden posts arranged in circles. Excavations revealed deep post holes.

Looking at the plans drawn by the Cunnington's during their excavation of the site in 1930 you can see that inner post hole arrangement has cruciform configuration. The arms of the cross lead north-wast, south-east, south-west and north-west.

The Avebury 'Kennet'  avenue enters (or leaves) The Sanctuary at the north-west.

But when you are there, standing in The Sanctuary.... the post holes marked with red concrete are no longer accurately positioned.

After working out a theory of construction...

I lay out the lines using string.

And see how mixed up the post markers have become.
The little post in the middle of the triangle on the right should be the center post.

Next time I lay out the lines I will use the blue 'stone' markers.

The most obvious astronomical feature of the sky and the cruciform shape, and the directions the four passageways point to seems to indicate that the sun is the focus of the structure.

Freezing cold Midsummer morning! Sunrise.

Unfortunately...
The sun does not line up with the NE corridor at Midsummer if you look from the center of the circle (but wasn't there a post at the center)!

My first thought was, what difference has 4400 years of procession made to the position of the Sun rise?

My second thought is that tall posts are a different thing to low concrete markers and the only way I could ever understand this place would be to re-make it! The height of the posts changes the way things line up...?

My third thought was that perhaps the corridors were symbolic. That no one would stand in the center, it just had to look as if the sun shone into the heart of it, to people stood in an outer ring.

It was frustrating because  if The Sanctuary could be rotated (!) then the sun would line up with the corridors that radiate from the center post.

Could 4400 years have made enough of a difference to account for the discrepancy?

Not a very likely possibility, but let's see.

Basically the position of celestial north, marked CNP on the picture, has changed.

In our time, the sky rotates around the star Polaris

2400 BC the axis of rotation had shifted and there was no 'exact' pole star.
[LINK] Thuban.

Putting the images together shows how the celestial north pole has moved.

Curiously the effect of the shift on the position of the sun relative to the Earth changes nothing as far as the sun and moon are concerned, except the calender date on your software.

Conclusion.

• Axial precession is not significant when considering the position of the sun.
• But axial precession is significant when considering the position of distant stars and planets and their alignments to megaliths in the past.
• Axial precession does not change latitude.
• The 'arms' or 'corridors' of The Sanctuary may well align to the moon.
• Without knowing the height of the original posts, it is difficult to estimate the accuracy of the monuments alignments to the sun (and the moon...).

Note.

If the plan is rotated 13 degrees east to correct the magnetic declination in 1930...things line up better...but it is impossible to know if magnetic declination was accounted for or not without uncovering the post holes, so that remains an unanswered question.

With magnetic declination taken into account...

The avenues now line up with the solstice..