This is the ‘new’ version of a solar energy concentrator which creates a bright ‘mini-sun’ rising towards the heavens over the course of an afternoon. Frames either side, pointing towards the north-east, allow ropes to rotate the ‘sail’. Four frames are required; two to stabilise the front of the sail and two more for the opposing end:
I hung a ball off the hinge to make it clear where the hinge is: It's unnecessary, but I thought it might make it easier to see how the sun would appear to rotate around the Earth’s hinge (polar axis).
The test arrangement (above) is also a 30% reproduction of Stonehenge’s structure, but slightly lowered to make focusing easier: To duplicate the rigidity required, the frames have stabilizing cross-bars locked to ground-pegs at the bottom (stone was way too expensive).
Fixed mirrors (see bottom left in photo below) were placed in an inward facing circle at exactly the same place as Stonehenge’s inwardly facing outer stone circle. Energy is concentrated to the reflector (at the end of the ‘sail’) to produce the ‘mini-sun’:
I also covered the frames in cloth (photo below) to make the arrangement easier to visualise. Locating holes (preferably three) for the polar axis are required in the frame to the south: The same number of vertical holes, directly south of centre, exist at Stonehenge on its southern ‘Trilithon’ set (Stones numbered 53, 54 & the lintel 154):
The ‘Trilithons’ proved to be in exactly the correct place to allow hauling of the sail around the polar axis. From the 3-D virtual models I knew they would, but it was great to see it work in practice:
In ancient times, and right up until a few hundred years ago, the Earth was thought to be fixed at the centre of the Universe. This system shows how the Sun appears to rotate around the polar axis of the Earth; shown here as a ball suspended off the hinge:
The Sun can be used to create the appearance of a ‘sun-child’ rising up on the cross formed by the sail and the rod of the polar axis: As the sun sets, the ‘child’ rises. In the picture below, a view is shown as it would appear if you were standing in Stonehenge itself. Two ‘suns’ can be seen:
The arrangement can be set up in about two hours. I didn't bother to accurately align anything for this test, so some of it will be arranged slightly differently for the eventual configuration. It’s also become apparent that the best time to do this will be in winter: In the earlier winter tests, perhaps due to the coldness, the air shimmers and creates an expanded ghost-like form around the reflector.
Note that sun-glasses are essential: