The following article will attempt to establish a relationship between the East row of stones at Callanish I (Calanais), the equinoctial (Spring & Autumnal) full moons and the ritualistic or ceremonial importance of such events and the relevance in modern society. The essay is based on astronomical study, field work and knowledge of the ancient civilisations of Europe and beyond. 

Callanish (Calanais) is located on the Isle of Lewis in the Outer Hebrides of Scotland, and home to a fascinating collection of stone circles and standing stones. The remoteness and climatic conditions of these islands has helped enormously in the preservation of this ancient and complex ritualistic landscape. You may hear Callanish referred to as the Stonehenge of Scotland, but this hardly does it justice, the location and setting within the landscape stands this monument apart from all others. No where else can we see such a complex and fascinating collection of lunar phenomena fixed in stone by a succession of Bronze Age people. The myth of the place had travelled across Europe and probably beyond for thousands of years, and echoes can be found in the writings of Diodorus of Siculus as he reacounts tales of earlier travellers.

A brief history of Callanish

Archaeological study suggests the erection of the first stones at Callanish I (Calanais) began around 3000BC. The construction started with the tallest of the stones, the central monolith, subsequently followed with the erection of 13 stones forming a flattened circle encapsulating the central monolith. At a later period the North avenue and the South and West rows appeared. The East row was added to the complex around 1800BC some 1200 years after initial work began. The central burial cairn was the last feature added to the site appearing at some stage between 1800BC and 1000BC after which, the site was abandoned and slowly became engulfed in peat. The East row at Callanish I (Calanais) consists of five erect stones, many early plans of the site only recorded four, the fifth stone was re-discovered by Margaret and Gerald Ponting in 1977 and was successfully re-erected in its true position by the Monuments Department of the Scottish Development Department in 1982.

The East row and a background of previous studies




Admiral H Boyle Somerville suggested the East row indicated a line to the rising of Pleiades, a group of bright stars which for many cultures had associations with funerary rites. At around 1800BC the constellation could be seen rising in the East during the Autumn months. Somerville was an early convert to the field of archeoastronomy and undertook the first modern survey of Callanish (Calanais). He reported his findings in a paper read to the Royal Anthropological Institute and had the same paper published in the British Astronomical Association journal November 1912. Much of Sommervilles work centered around lines to stars, but he gave us the first clue that the builders of Callanish where studying the lunar cycles, he found that an alignment accurately indicated the Northern extreme position of the rising full moon around the time of the Winter solstice during the 18.6 year lunar cycle. He also connected the writings of the Greek writer Diodorus of Siculus to Callanish. 


We only know the Hyperboreans lived somewhere far North of Greece, but it's only at the latitude of the Isle of Lewis do we see the moon behave in such a dramatic fashion of which the Greek historian wrote. The work of Margaret Curtis, Ronald Curtis and Gerald Ponting has done much to interpret and illustrate this remarkable lunar phenomena and the relationship to the range of hills know as the sleeping beauty or the old woman of the moors. At the cusp of the major lunar standstill when the moon reaches it's southern extreme for a few consecutive months the full moon rises from behind the sacred hill range skimming the horizon for several hours before setting behind the Harris hills. Dramitaclly, when viewed from the end of Northern avenue the moon is seen to set at the base of the central monolith. The hills are as much a part of the monuments as the stones themselves. This landscape is currently under threat from a controversial wind farm development.

No one seemed to take on the mantle of the work carried out by Somerville and Lockyer before him in the years between the wars and beyond. It wasn't until 1963 did a resurgence of interest take place when professor Gerald Hawkins of Boston University armed with a computer turned his attentions to Stonehenge. His calculations showed 10 stone alignments to solar azimuths and fourteen to lunar. He also went on to popularise the idea that the 56 holes of the Avbury circle marked the 56 years it takes for the moon to complete it's eclipse cycle. Hawkins also surveyed Callanish and concluded the "Callanish people were as precise as the stonehengers but not as scientifically advanced", not surprising perhaps, as Callanish pre-dates Stonehenge by 500 years. Hawkins contradicted Sommervilles Pleiades theory and suggested the East row may indicate the Equinoctical moon.

The Hawkins suggestion intrigued me and led me to study the idea in greater detail. After building the table of moonrise positions for a full metonic period I was able to verify their validity by an eyewitness account in 2002. In my opinion it is most likely the East Row was erected to signify the horizon position of the rising Spring & Autumnal full moons (Equinoctial moon, the full moon closest to the solar equinoxes) in other terms and significantly because we know these times as Easter and the harvest moon. The Spring and Autumnal full moons occur at a different dates between the months of March and April, September and October respectively each year during the lunar cycle. What makes these dates special is the fact that these two lunations are the only time the same moon rises in the same position with annual regularity as the 19 year lunar cycle swings between its Northern and Southern extremes. Just as importantly and what makes this event so unique is these full moons occur within the hour of the sun setting on the opposite horizon. Although the marked moonrise position is accurate in the main over the moons cycle there are years where we see a degree or two deviation. Still, these slight deviations are still unmistakable indicators and don't detract from the event it's self. We must remember it is the theatre of the event, the play of light and the ceremonial atmosphere created which is significant and not the critical degree of accuracy. I think it's important to recognise that although the builders studied the skies in a scientific manner, the construction of the temples are symbolic embodiments of their knowledge and beliefs and not just or even perhaps at all, the instrument of their scientific observation. Interestingly, we can see dates for several Lunar eclipses (when the earths shadow passes over the moon) we can only speculate what the Bronze age people made of these events. From the table below we can see the whole 19 year pattern of moon cycles and the individual Autumnal moonrise positions including several eclipse events. It is hoped the table will not only provide evidence to support this theory but will also encourage people to visit the site (or any circle across Britain for that matter) during these dates. During a time when calendars were based on lunations we can not ignore the full moons closest to the equinoxes as for many civilisations past and present they have special significance.


Summer’s End, Winter's end, times of festival

Why would the Spring and Autumnal moons be significant to the people who erected the stones? We can find clues to support the idea of a ritual or ceremonial event held at this time of year by looking at other cultural traditions spanning Europe and beyond. Prior to the rise of the Roman empire all calendar systems where based on lunation's, and perhaps only in the Western world have the lunar cycles been erased from our psyche. This is clearly demonstrated in China. The Chinese Mid Autumn festival to this day takes place at the Equinoctial full moon and is the second most important holiday in China, the Chinese new year being the first. In New Zealand and Maori culture, there has been a recent revival of an ancient festival named Matariki, here the combination of the rising Pleiades and the next new moon marks the time of festival and remembrance and the start of the Maori New year. This festival echoes those of the ancient Celts. There is a Scottish Gaelic word Samhainn or Samhuinn (for the feast). The festival of Samhain is an end of summer celebration and many believe it's the beginning of the Celtic New Year. The Samhainn festival is dedicated to the harvest and the dead and has survived in many guises till this day. Of course we must be careful not to directly transpose Iron Age and Medieval Celtic traditions to the Neolithic and Bronze Age periods, evidence shows the Celts appeared as a society a thousand years after the East row of Callanishs (Calanais) was erected. What is demonstrated is the importance of the star and moon cycles in fixing annual festivals to cultures around the globe. Even the Easter festival of the Christian religion is aligned to the moon cycles which is why it falls sometime between late March and early April each year. No doubt a throwback to Pagan times before. 

The Sun and Moon in a Theatre of Light.

To understand the significance of this event in the yearly calendar we must try to imagine life in the Hebrides 4000 years ago, only by doing this can we begin to understand the hardships and fears people faced. The Bronze age period of stone circle building was a golden era for the Hebrides, a time when it was experiencing a warmer and drier climate than it does today. However, it would be a mistake to imagine life being easy here, the recent discovery of a Bronze Age peat stack discovered on the Isle of Barra paints a picture of life and climate not so different and unrecognisable from now. A Hebridean society, existing as it does today, on the very fringes of Europe.

Summer is at an end, food harvested and safely stored for winter. The mornings grow noticeably colder and days shorten at an alarming rate as they do at this latitude, a long winter looms ahead. Many families face the coming winter with trepidation, aware not all of them will see the corresponding festival in the spring. Have they enough food to survive or will it perish or be stolen, have they harvested enough peat and fire wood to keep them warm, and will their house stand strong, and provide protection through the winter storms the Atlantic Ocean will inevitably throw at them. The Pleiades are spotted in the night sky, a community is busy as it gathers and prepares for a festival as the full moon nears, from miles around whole families make the pilgrimage to the ritual landscape of Callanish (Callanais), a chance to make offerings to the gods and the ancestors in thanks for the harvest and in return for safe passage through the winter. So at Callanish (Calanais) the stage is set, for an hour or so and for a few days every year, a short stone row marks a position on the horizon where the Autumnal full moon rises in opposition to a setting sun in the west, signifying an end to the abundance and richness of summer, hailing the dominance of night over day as winter approaches. At this time Callanish (Calanais) becomes not only the central point of ritual and festivity for the community, but also it would appear the pivotal point around which their deities revolve.

Calanais I (Callanish) Autumnal Full Moon Event

Year Equioctial
Full moon
  1. Moonrise Time
Moonrise Azimuth
Sunset Time Lunar
20-Sep-2002 7:59 PM 108.00 7:27 PM  
21-Sep-2002 8:05 PM 98.00 7:25 PM  
22-Sep-2002 8:12 PM 89.00 7:22 PM  
9-Oct-2003 6:56 PM 90.00 6:34 PM  
10-Oct-2003 7:00 PM 79.00 6:31 PM  
11-Oct-2003 7:05 PM 69.00 6:28 PM  
27-Sep-2004 7:23 PM 100.00 7:05 PM  
28-Sep-2004 7:26 PM 88.00 7:03 PM  
29-Sep-2004 7:29 PM 76.00 7:00 PM  
17-Sep-2005 7:50 PM 101.00 7:35 PM  
18-Sep-2005 7:53 PM 88.00 7:32 PM  
19-Sep-2005 7:56 PM 75.00 7:29 PM  
6-Oct-2006 6:31 PM 84.00 6:42 PM  
7-Oct-2006 6:35 PM 70.00 6:39 PM  
8-Oct-2006 6:40 PM 56.00 6:36 PM  
25-Sep-2007 6:54 PM 99.00 7:13 PM  
26-Sep-2007 6:57 PM 85.00 7:11 PM  
27-Sep-2007 7:01 PM 72.00 7:08 PM  
14-Sep-2008 7:20 PM 98.00 7:43 PM  
15-Sep-2008 7:24 PM 87.00 7:40 PM  
16-Sep-2008 7:29 PM 74.00 7:37 PM  
2-Oct-2009 6:05 PM 90.00 6:52 PM  
3-Oct-2009 6:11 PM 79.00 6:49 PM  
4-Oct-2009 6:19 PM 69.00 6:47 PM  
22-Sep-2010 6:41 PM 88.00 7:22 PM  
23-Sep-2010 6:49 PM 79.00 7:19 PM  
24-Sep-2010 6:58 PM 69.00 7:16 PM  
11-Sep-2011 7:11 PM 96.00 7:53 PM  
12-Sep-2011 7:21 PM 87.00 7:50 PM  
13-Nov-2011 7:32 PM 78.00 7:47 PM  
28-Sep-2012 6:12 PM 90.00 7:07 PM  
29-Sep-2012 6:27 PM 82.00 7:00 PM  
30-Sep-2012 6:42 PM 73.00 6:57 PM  
18-Sep-2013 6:55 PM 94.00 7:32 PM  
19-Sep-2013 7:14 PM 85.00 7:29 PM  
20-Sep-2013 7:33 PM 76.00 7:37 PM  
8-Sep-2014 7:36 PM 99.00 7:01 PM  
9-Sep-2014 7:59 PM 89.00 7:58 PM  
10-Sep-2014 8:22 PM 81.00 7:55 PM  
27-Sep-2015 7:05 PM 91.00 7:09 PM  
28-Sep-2015 7:30 PM 82.00 7:06 PM Eclipse 1:0am - 6:24am
29-Sep-2015 7:36 PM 73.00 7:03 PM  
15-Sep-2016 7:26 PM 105.00 7:40 PM  
16-Sep-2016 7:49 PM 97.00 7:38 PM Eclipse 6:00pm -  9:55pm
17-Sep-2016 8:12 PM 88.00 7:35 PM  
4-Oct-2017 6:58 PM 97.00 6:47 PM  
5-Oct-2017 7:17 PM 88.00 6:44 PM  
6-Oct-2017 7:37 PM 79.00 6:42 PM  
24-Sep-2018 7:46 PM 103.00 7:16 PM  
25-Sep-2018 8:00 PM 91.00 7:13 PM  
26-Sep-2018 8:15 PM 82.00 7:11 PM  
13-Sep-2019 8:20 PM 108.00 7:48 PM  
14-Sep-2019 8:32 PM 100.00 7:45 PM  
15-Sep-2019 8:43 PM 91.00 7:42 PM  
30-Sep-2020 7:25 PM 102.00 6:58 PM  
1-Oct-2020 7:33 PM 93.00 6:55 PM  
2-Oct-2020 7:41 PM 84.00 6:52 PM