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Rollright 2

Photographic survey of the astronomical alignment from the Rollright stone circle to the Whispering Knights dolmen, Oxfordshire.

Although thick haze lay on the horizon at sunrise on the 11th March, 1999, several images were secured which may be montaged allowing the track of the Sun to be extrapolated backwards to the rising point on the horizon.

These were not the best conditions for observing to a horizon mark. The far hill was no higher than the backsight, the Rollright circle, and the observing line was nearly horizontal passing through several miles of lower atmosphere with it's attendant haze. Even without modern pollution factors this photograph illustrates what may be the principal reasons for the relative lack of precision astronomical sites in lowland Britain:            Without high hills the altitude of lines of observation cannot be raised enough to shorten their distance through the atmosphere.            Years of observing experience in the western highlands of Britain shows that more days of higher wind speeds, heavier precipitation and greater incidence of frost also contribute to better seeing conditions throughout the year. Strong winds disperse and mix low layers of haze and mist. Heavy rain has a considerable effect on air clarity; it rinses out not only dust and pollution particles but also moisture droplets. Early and late frosts may have an overnight clearing effect on damp atmospheres.

The Correlated images

Here is thesynthesised image derived in January 1999 from Alexander Thom's survey in 'Megalithic Sites in Britain' 1967. To the right is the photographic survey from the series of images secured at sunrise 11th. March 1999.

Dec. -4deg. (calculated)

Dec.-3deg. 52.5min. (observed).

We can see, despite haze and tree growth on the horizon, that the correlation with Thom's work is very close. The required declination for calendar interval 16.5 had been attained 6.5 hours prior to the sunrise of the 11th. March.

The King's Men.

Here is a view across the stone circle with the holed stone in the centre. The stones of the ring are called the King's Men.

The distance from the centre of Rollright stone circle to the Whispering Knights dolmen is 364 metres, (398yds, 439 Megalithic Yds). This is a very short alignment for catering to accurate time keeping. If there never existed a clear marker on the far horizon then the distance to the dolmen is so short that an observer standing 2.39metres, (7.84feet), to either side of the centre of the circle would record an error of plus or minus one whole day in the estimation of this calendar division. It appears to be an invariable rule of the stone ring builders that the true centre of construction was never marked directly by a stone. If the Rollright to Whispering Knights alignment were to have any practical use the precise observing stance would need to be indelibly marked. The holed stone sits exactly astride this alignment and is likely to be a deliberate device marking the backsight proper.

The Whispering Knights. The Whispering Knights are thought to be the remains of the uprights of a dolmen which held a large capstone. Presumably this entire structure was buried in a cairn of smaller boulders shortly after erection thus few of the community which it served may have been aware of the evocative profiles these stones present. The King's Stone. This is a synthesised image of the King's Stone stellar alignment based on Thom's survey. Megalithic Sites in Britain 1967 p63.         Across the modern road , some 100 metres distant, stands a large solitary standing stone known as the King's Stone. From the centre of the stone circle the King's Stone lies at an azimuth of 29 degrees. This orientation indicates the place on the horizon where Capella, a first magnitude star, rose in 1750 B.C. Dating a stellar alignment employs different calculations from those used to date a solar or lunar indicator. The rising point of a star does not move with the seasons, as the Sun's does, nor with a monthly cycle like the Moon's. The position varies with a longer time span averaging some 1.5 degrees in declination per century coupled with each star's proper motion among the star field. This translates to over 2 degrees of azimuth shift on the horizon- about 4 solar diameters in 100 years. <<<Back with comments or queries- powys@megalithicsites.co.uk