Newgrange is famously aligned so that the rays of winter solstice sunrise enter its roof box and shine deep into the chamber. But was it also built so that the chamber could capture the light of the Dog Star (Sirius) in prehistory? And was this suggested in mythology? Anthony Murphy investigates. In Island of the Setting Sun: In Search of Ireland's Ancient Astronomers, first published in 2006, Richard Moore and I suggested that in addition to the sun, there were other objects that could shine into Newgrange. These included the moon and Venus, and our research showed that both these planets wou ..read more

The Cygnus Enigma examines the link between megalithic passage-mound of Newgrange, the myths which relate to that eminent monument, and other interesting factors which together form a fascinating ancient mystery. In our investigation, we examined the relationship between the astronomical alignments of Newgrange and Fourknocks, the whooper swans which winter at Newgrange in large numbers, the constellation Cygnus and the numerous myths and stories about Newgrange relating to swans. The fields near Newgrange provide a wintering ground for a large flock of whooper swans. The whoopers migrate ..read more

Some time after 6,000 years ago, a remarkable community of people arose on this island. They were the megalithic builders – farmers, astronomers and engineers. They left monumental, indelible structures crafted from stone and earth which were to stand the test of aeons of time. These people were responsible for creating Ireland's most remarkable monuments. They were the Neolithic sky watchers. Their constructions are Ireland's best known, most explored, and possibly least understood, monuments. The most famous of these, Newgrange (known in ancient Irish manuscripts as Síd i ..read more

What is the Metonic Cycle of the moon? Here's a very interesting question which many astronomers would initially imagine is easy to answer: "If you saw the full moon above Orion tonight, when would you expect to see another full moon in EXACTLY the same position among the stars again?" If that's got you thinking, don't be surprised. The answer will not roll off your tongue, even if you are an astronomer! The first time I was asked that question, I was at a loss. You see, the moon's movements through the sky are not straightforward, like those of its companion, the sun. We know&n ..read more

Dark Skies - Unraveling the cosmic vision of Ireland's Ancient Astronomers. An article by Anthony Murphy published as the cover story in the July 2008 issue of Astronomy & Space magazine. The article looks at some of the issues affecting our appraisal of the capabilites of the astronomer builders of 5,000 years ago and examines some of the evidence pointing towards a more complicated knowledge than is currently acknowledged. From Newgrange to Ireland's Stonehenge to the mountains of Sligo, we follow the cosmic trail left by our ancient ancestors. Imagine yourself gazing up at the blackest ..read more

Old Irish Zodiac - the constellations of the Zodiac as they are known in the Irish language. Ecliptic star groups in the Irish language Zodiac Name Old Irish Name Meaning Symbol Aries Réithe Ram   Taurus Tarbh Bull   Gemini Castor & Pollucs The Twins   Cancer Portán Crab   Leo Cú Hound   Virgo Oigbhean Young Woman   Libra Scálai Scales Scorpio Scorpion Scorpion   Sagittarius Laoch Caithte Saighead Hero of the Thrown Arrows   Capricorn Pocán The Goat   Aquarius An tUisceadóir Water Carrier   ..read more

In this article, Gillies MacBain examines whether the builders of Newgrange were aware of the leap year – how they might have discovered it and what they might have done to incorporate knowledge of the leap year into the design and structure of the monument. If you ever become tired of the bland certainties repeated by Boyne Valley tour guides – position yourself right at the back of the group and when your moment comes, fire out this question: “How did Newgrange handle leap year?” There will be a pause. Well, how did they? The tour guide will not know. No archaeological treatise will tel ..read more

What did equinox mean to a Neolithic astronomer? Anthony Murphy examines our definition of the equinoxes and how this would not have been relevant in the Stone Age. So why are there equinox alignments in the Neolithic? Today is autumn equinox (this article was written on autumn equinox 2019). Astronomically, the equinox occurs when the sun crosses the celestial equator. Equinox derives from the latin for "equal night" and is said to be the time when night and day are of equal length. At the equinox, the sun rises due east and sets due west. Equinox sunrise viewed from the entrance of Cairn T ..read more