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Kerbstones at Knowth. Paul Griffin.



The objective of this programme would be to investigate the hypothesis that builders of the megalithic monuments used counting to anticipate significant astronomical events, and included facilities for such counting in the design of the monuments themselves.

The American astronomer Dr. Gerald S. Hawkins and Cambridge Astronomy Professor Fred Hoyle believe that the 56 Aubrey holes at Stonehenge were designed to track the lunar nodal cycle, which is associated with lunar standstills and eclipses. An important feature the chambered passage-mounds in Ireland and Scotland is the ring of large kerbstones which mark their perimeter. Evidence suggests that, like the Aubrey holes at Stonehenge, the 127 kerbstones at Knowth may have been a device for counting tropical moons; 127 is the number of tropical moons in half a lunar nodal cycle. Knowledge of the rhythm of heavenly cycles would have given Neolithic people a way to anticipate and confirm the periodic sighting of heavenly bodies along alignments, such as the points on the horizon where the sun rises and sets during the Equinoxes and Solstices.

To this day, religions use astronomical events to determine the correct dates on which to celebrate important feasts. Many of the feasts in the Christian liturgical calendar depend on the date of Easter which itself depends on astronomical events. The formula for determining Easter involves the intersection of three separate cycles: the cycle of the sun, the cycle of the moon, and the cycle of the earth's rotations in the Judaic tradition - the seven-day week. Easter is the first Sunday after the first full moon after the vernal equinox. The earliest Christians in Ireland clearly had a strong interest in the determination of the date of Easter. It marked a significant difference between the Celtic church and the Roman church. It is likely that an interest in astronomy as the way to determine the appropriate time for communal rituals predates the Christians and the Celts in Ireland. The evidence is probably to be found in the monuments. It is the goal of this research programme to learn to read it.


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Updated 22 April 2001
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