Hello George, The link to Pete's film based on your calculation of the parallel is still on the site of Eric Avebury. I can't seem to link to it from here but could do this morning.
It's the one from 15th May or end July of 2009 from the palisades enclosure, which of course works very well.
My one from the Spring Equinox that year did not involve moving the tripod, as that would have defeated the whole object, but I was a bit close so I had to alter the camera angle and zoom in part way through. This is because I didn't know at the beginning that the sun was going to rise close to the angle of the slope. Of course once I realised what was happening I had to try to complete the sequence, so I posted it to Youtube with all its inherent ineptness because it was the occasion of the discovery.
It is of course very dramatic and beautiful even when the sunrise is steeper than the slope because as the sun rises it gets brighter and so appears to get bigger. It actually works well on the summer solstice; you may remember that there was a line among the palisades crop marks that ran at the azimuth of summer solstice sunset towards Silbury Hill. My later videos are from the end of that line in another palisades enclosure and work perfectly well. It seems to me entirely possible that the people who used the palisades enclosures noticed the sunroll effect and made something of it. I don't think anyone can argue that it was the reason for building Silbury Hill but I do think that if Silbury Hill was in any way the centre of a sun cult, which we don't know but it might have been (Sil, Sol), then the sunroll could reasonably be seen as a fitting attribute to that, no matter how many Tesco's roofs might have the same slope.
 Reply | with quote | Posted by MG
17th May 2016ce
14:24 |
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Re: The Geometry of Avebury (tiompan)