Cove & Pit-Arc Sunrise Alignments in 2016
|Quarter Day 1 (Imbolc)||February 4th||08:05||8:05 am||118.9||B|
|Semiquarter Day 1||February 26th||07:15||7:15 am||104.8||C|
|Spring Equinox||March 20th||06:16||6:16 am||88.8||D|
|Semiquarter Day 2||April 12th||05:16||6:16 am||72.8||E|
|Quarter Day 2 (Bealltainn)||May 5th||04:22||5:22 am||58.5||F|
|Summer Solstice||June 20th||03:29||4:29 am||43.2||G|
|Quarter Day 3 (Lùnasdal)||August 6th||04:29||5:29 am||57.9||F|
|Semiquarter Day 3||August 29th||05:14||6:14 am||72.2||E|
|Autumn Equinox||September 22nd||06:01||7:01 am||88.7||D|
|Today||September 27th||06:11||7:11 am||92.2||D|
|Semiquarter Day 4||October 14th||06:45||7:45 am||103.9||C|
|Quarter Day 4 (Samhuinn)||November 6th||07:33||7:33 am||118.4||B|
|Winter Solstice||December 21st||08:44||8:44 am||133.5||A|
In his excavation report on Cairnpapple, Stuart Piggott identified the site’s earliest Neolithic structures as: (1) an “irregular arc” of 7 stone-holes (A–G) cut into the basalt bedrock and (B–G) containing traces of cremation deposits; (2) an east-facing “cove” of 3 further stone-holes (PSAS 82 68–123). Piggott himself did not directly connect these two structures, nor did he suggest any calendrical function for them. However, such seems compelling when we map onto his excavation plan the sunrise azimuths for solstices (pits A & G), equinoxes (pit D) and quarter-days (pits B & F), with 4 additional dates apparently indicated exactly halfway between equinoxes and quarter-days (pits C & E) which I’m provisionally calling “semiquarter days” until I can think of something better. Whence this webpage, under development (particularly its maths) towards being a dynamically-programmed representation of Cairnpapple’s “Neolithic Solar Calendar”. If you’ve got any useful feedback, I’d be glad to hear from you.
Astronomical data calculated using NASA’s JPL HORIZONS ephemeris tool. Times & azimuths are topocentric refracted estimates for the centre of the solar disk on (currently) a notionally level horizon.
View maps at OS Magic or Google. Visit the non-virtual Cairnpapple with Historic Scotland. Consult the local weather oracle at the Met Office. Find illumination in Llyfr Aneirin at The National Library of Wales.