Horizon astronomy as an ancient cultural technique
During the dawn of mankind, observing the shifting positions of the rising and setting points of the Sun on the apparent horizon was the only possibility to construct a solar calender that times the practical and ritual order in society.
Remains of buildings from past cultures still display today that astronomical concepts played an important part in the social and religious life of our ancestors.
The stone age complex of Stonehenge in southern England is the most famous example of aligning a monument towards the Sun. The axis of symmetry - and the procession way as its continuation - point towards the direction of the rising Sun during the longest day in summer and of the setting Sun during the shortest day in winter. Another well known example is the passage tomb of Newgrange in Ireland. Its burial chamber is illuminated daily for approx. 15 Minutes during the time of the winter solstice by the rising Sun, shining down the passage way into the interior.
An archaeological dig in Goseck in Sachsen-Anhalt in Germany has revealed the up until now oldest comple of circular ditches with astronomical function. 7000 years ago an enclosure was created by a circular ditch and two palisades that has entrances and unobstructed views designed with astronomical constraints.
The Stardisk of Nebra is prove of the attention bronze-age society gave towards the celestial bodies. The golden limb segments span the region that can be covered by the rising and setting directions of the Sun along the horizon and documents the tradition of observing then horizon in this cultural time period as well.
To what extent stone-age man occupied himself with the stars, and to what purpose ancient astronomy was carried out, is since decades a research topic of astronomy, archaeology, and Ethnology. The resulting interdisciplinary research areas of archaeoastronomy and ethnoastronomy analyse the astronomical knowledge of ancient mankind and its integration into the context of prehistoric society.
Horizon astronomy today – A chance for a conscious experience of nature
The modern civilisation does not require the visible annual Solar and Lunar events to structure its calendar and chronological structure. Since basic horizon observations are not necessary any more, the key element of a conscious celestial observation and the related sensory experience have become obsolete and have been lost, together with the awareness of a millennia old cultural activity and archaic observational methods. This cultural decline goes hand in hand with the general lack of knowledge with respect to basic astronomical occurrences. The knowledge of how Sun, Moon, and stars move above the local horizon are nowadays not very well pronounced. Furthermore, basic astronomical education is not included in the national curriculum for schools.
Since 1999 the 'Initiativkreis Horizontastronomie im Ruhrgebiet e.V.' has developed proposals for the construction of observing installations accessible to the public, to revive the lost tradition of visual horizon observations and to advance elementary astronomical observing culture. Each of these buildings incorporate different ancient observing techniques. Two of the installations proposed by the private initiative have already been realised by the Regionalverband Ruhrgebiet (RVR) on top of the Halde Hoheward: the obelisk as a shadow caster in a horizontal sundial and the horizon observatory.
Last Update: 10th February 2009