Guide to the Cosmos

 Making the Wonders of our Universe Accessible to Everyone


Newgrange — World’s Oldest Observatory



Built in 3200 B.C., 52 centuries before the Hubble Space Telescope, Newgrange in Ireland’s Boyne Valley may be mankind’s first astronomical instrument. It predates both Stongehenge and the Pyramid of Khufu by several hundred years.


We can only imagine why prehistoric farmers built a 200,000-ton edifice with enormous boulders from mountains 30 miles away.


But one fact is certain: Newgrange is a precise astronomical instrument.




Rock walls enclose a dirt mound that is 270 feet in diameter and 45 feet tall. An ornately carved entrance leads to a mammoth stone passageway, ending in three chambers, possibly enshrining the remains of illustrious ancestors.


For about 17 minutes on each of five days surrounding Winter Solstice, the rising Sun traverses a special aperture above the main entrance, and snakes down the winding, narrow, 63-foot-long passageway, ultimately illuminating the main chamber.


The ceiling of the inner chamber complex is 20 feet tall. Terraced stone slabs make it absolutely waterproof, no small feat in Ireland (where the Dingle Annual Rain Festival begins each year on January 1st, and ends on New Year’s Eve). 


Some scholars believe Newgrange was a monument to the continuity of life. 


The Boyne Valley is about as far north as Dutch Harbor, Alaska. As winter approaches, temperatures plummet, vegetation dies, food becomes scarce, and daylight shortens to less than 8 hours. Neolithic people might easily have feared all life might end soon. 


Newgrange provided hope, announcing the passing of the darkest days, the beginning of nature’s renewal, and the turning point back toward warmth and abundance.


Joan and I have just returned from Newgrange at Summer Solstice, when the weather was much better.


Due to the precession of Earth’s orbit, Newgrange now runs about 4 minutes slow, but astronomers calculate it was spot on 5200 years ago.





Best Regards,



August, 2017


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