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The New Pictish Calendar


Today's date in the New Pictish Lunar Calendar is: 2 Geamhain, 3043 P.E.

Geamhain 3043
Lu Ma Ci Ar Ao Sa Do
  
1
26/4
2
27/4
3
28/4
4
29/4
5
30/4
6
1/5
7
2/5
8
3/5
9
4/5
10
5/5
11
6/5
12
7/5
13
8/5
14
9/5
15
10/5
16
11/5
17
12/5
18
13/5
19
14/5
20
15/5
21
16/5
22
17/5
23
18/5
24
19/5
25
20/5
26
21/5
27
22/5
28
23/5
29
24/5
30
25/5
   

The New Pictish lunar calendar is a notional calendar that I have devised for my own interest and enjoyment. It is not meant to represent any real calendar that may or may not have ever existed at any time. It is based partly upon the Gaulish "Coligny" calendar, so called because a bronze tablet was discovered near Coligny, France in 1897 that details the design of a lunisolar calendar, i.e. one that attempts to keep in synchronisation with the lunar and solar cycles (see elsewhere on this site for more details). The New Pictish Calendar is my attempt to create a lunisolar calendar that keeps in synchronisation with these cycles as closely as possible whilst being reasonably easy to use, calculate which years are leap years and so on.

Mean Months and Years

The system used to achieve this synchronicity is based on the 19-year Metonic cycle, whereby the Moon's phases occur on or around the same dates at 19-year intervals. To follow this cycle exactly, though, would result in the months drifting gradually later in the year over a long period of time. This is actually occurring in the Hebrew calendar, whereby the month of Nisan, which contains Passover, is drifting later such that Passover will eventually occur in the summer if it is not corrected. The aim, therefore, is to achieve a mean lunar month as close to the actual mean synodic month and a mean year as close to the actual mean solar year as possible. A pure 19-year cycle with 7 long years (i.e. those with an intercalary month) and 4 abundant years (i.e. those with an additional day) per cycle would give a mean lunar month of 29.53191 days, i.e. 6,940 days divided by 235 lunar months, which is 0.00132 more than the actual mean synodic month of approximately 29.53059 days. If a cycle only has three abundant years, i.e. a total of 6,939 days, then the average would be 29.52776, which is 0.00293 days too short. Over long periods of time the calendar would drift so that it no longer properly corresponded to the correct phases of the moon. With respect to the solar year, a cycle of 6,940 days over 19 years would give an average year of 365.26316 days, which is 0.02078 days too long, whereas a 6,939-day cycle gives a mean year of 365.21053 days, 0.03185 days too short.

Cycles

To achieve greater accuracy, therefore, it is first necessary to use a "grand cycle" which contains multiple 19-year cycles, and then add 3 or 4 days as necessary in each cycle to obtain mean months and years that more closely match reality. This, however, is difficult to achieve using cycles that are exact multiples of 19 years. The answer is to "truncate" one of the cycles from 19 years to 11 years. If this is done in every 18th cycle we get a mean lunar month of 29.53062 days, which is only 0.00003 days longer than the actual mean lunar month, and a year of 365.24252 days, which is only 0.00014 days longer than the actual mean solar year at the present time.

Structure of the Calendar

The precise structure of the calendar is as follows:

  1. A "grand cycle" comprises seventeen 19-year cycles and one 11-year cycle, i.e. 18 cycles in all;
  2. If these 18 cycles are arranged in groups of three, in the first five groups of cycles the first and second cycles of each group of three have 6,940 days, and the third has 6,939;
  3. In the sixth and last group of cycles the first two contain 6,940 as normal but the third only has 4,016 days.
  4. Each of the 19-year cycles has 8 or 9 regular years of 354 days, 3 or 4 abundant years of 355 days and 7 long years of 384 days;
  5. The 11-year cycle has 5 regular years of 354 days, 2 abundant years of 355 days and 4 long years of 384 days;
  6. For long-term adjustment, a further day is subtracted in every 216th cycle (12 grand cycles), i.e. roughly once every 4000 years, when the extra day in year 4 is dropped.

The following table shows how each cycle is structured. The first, second and third cycles of each group of three within each grand cycle follow this pattern, and the last column shows the structure of each 18th cycle of 11 years. Each column shows whether an extra day or an extra month is added to the regular year of 354 days.

Year
1st cycle
2nd cycle
3rd cycle
18th cycle
1
reg
reg
reg
reg
2
+month
+month
+month
+month
3
reg
reg
reg
reg
4
+day
+day
+day
+day
5
+month
+month
+month
+month
6
reg
reg
reg
reg
7
+month
+month
+month
+month
8
reg
reg
reg
reg
9
+day
+day
+day
+day
10
+month
+month
+month
+month
11
reg
reg
reg
reg
12
reg
reg
reg
 
13
+month
+month
+month
 
14
+day
+day
+day
 
15
reg
reg
reg
 
16
+month
+month
+month
 
17
reg
reg
reg
 
18
+month
+month
+month
 
19
+day
+day
reg
 

By dropping the extra day that is normally added in year 11 in every 216th cycle, the mean lunar month becomes 29.5306 days, just 0.00001 days of a difference from reality, and a mean solar year of 365.24229, just 0.00008 of a difference. This produces an extremely accurate calendar with regard to the mean lunar month. However, over time the cycles will occur slightly earlier, such that by the year 10,000 CE they will be occurring approximately two days earlier in the Gregorian calendar than at the beginning of the calendar in the year 1,207 BCE, approximately 11,000 years earlier. Another small adjustment will therefore have to made at some point to keep the calendar aligned with the solar year, but as it stands the calendar is good for several millennia without adjustment and will correspond more than adequately to the phases of the moon for quite some time.

Structure of the Months

The months in the calendar are as follows:

#
Moon Pronunciation Meaning Days
1
Samhain Sah-win/Sa-vin (Summer's End/Seed Fall?) 30
2
Dumhainn Doo-in/Doo-vin (World Darkness/Darkening?) 29
3
Riùr Ree-oor/Roor (Cold & Ice?) 30
4
Naghaid Nah-hid (Staying at Home?) 29
5
Uarain Ooer-un (Cold/Cold's End?) 30
6
Cuithe Kwee-huh (Wind) 29 {30}*
7
Geamhain Gyah-win/Gya-vin (Winter's End?) 30
8
Siùfainn Shoo-fin (Half-spring/Brightening?) 29
9
Eacha Ech-uh (Horse?) 30
10
Eilmì Ell-mee (Claim?) 29
11
Aodhrain Air-un/Urr-un (Arbitration?) 30
12
Cainteal Cant-yull (Song?) 29
13
{Eadràn} Ed-rahn (Intercalary/Between?) {30}**
* Has 30 days in years 4, 9, 14 & 19 in the first and second cycles in each group of three, years 4, 9 & 19 in the third cycle and years 4 & 9 in every eighteenth cycle. The extra day is dropped in year 4 of every 216th cycle.
** A leap month is added in years 2, 5, 7, 10, 13, 16 and 18 of every cycle, apart from every 18th cycle, when a month is added in years 2, 5, 7 and 10.

Translation of the names of the months

There is much debate about the names of the months. In fact it is not known even if the months occurred at the times of the year depicted in this calendar, for example "Samonios' may not be cognate with "Samhain". However, the associations and translations used are those generally accepted as being most likely, but it should be noted that nobody actually knows with certainty when in the year the months occurred nor what the true translations of the names are.

New Moon or Full Moon

Another debate is whether the months would have begun at new moon or full moon. In fact, in relation to the Gaulish calendar Pliny the Elder says in Natural Histories, 16, 249: "the sixth day of the lunar cycle - this is from when these tribes count the first days of the months and the year", so the suggestion here is that each new month began on the sixth day following the new moon. However, most known lunar calendars begin each month at or just after new moon (i.e. lunar-solar conjunction) or at first sighting of the new lunar crescent. I have therefore adopted the practice that each month begins at or near new moon.

Epoch and New Year Dates

The epoch of the calendar is 8th November -1026 Gregorian (i.e. 1,027 B.C.E.). This date was not chosen specifically but was arrived at by working back from the start date of the current cycle, 9th November 1999. The latter date was chosen for personal reasons, and as a result each cycle has been starting on or around the 9th November. The calendar is structured, however, to keep the average start date nearer the 5th-7th November, i.e. as close as possible to the mid-point between the autumnal equinox and the winter solstice.

The date of each new year, therefore, will usually be the nearest new moon to the halfway point between the autumnal equinox and the winter solstice. Some traditions would place the new year date, i.e. the start of the month of Samhain, earlier than this so that it is the full moon that is closest to the midpoint that Samhain is celebrated. In my version, however, Samhain is celebrated at the nearest new moon, as there is nothing that says that all festivals were held at night or that a full moon was required to do so. True, they did not have electric light, but they had fire, and at Samhain fires are often lit as part of the festivities. It is not without credence, therefore, that they did this to light up the darkness and worship the artificial light that would be needed over the winter period. This ritual may have similar origins to Diwali, the Hindi festival of lights, which coincides with the Celtic new year in most years. The short answer is "nobody knows", but the new moon system is the one that I have chosen to go with.

The following table shows the starting dates of each year in the current trio of lunar cycles.

Year
Cycle 163
Cycle 164
Cycle 165
1
8 Nov, 1980
9 Nov, 1999
9 Nov, 2018
2
28 Oct, 1981
28 Oct, 2000
29 Oct, 2019
3
16 Nov, 1982
16 Nov, 2001
16 Nov, 2020
4
5 Nov, 1983
5 Nov, 2002
5 Nov, 2021
5
25 Oct, 1984
26 Oct, 2003
26 Oct, 2022
6
13 Nov, 1985
13 Nov, 2004
14 Nov, 2023
7
2 Nov, 1986
2 Nov, 2005
2 Nov, 2024
8
21 Nov, 1987
21 Nov, 2006
21 Nov, 2025
9
9 Nov, 1988
10 Nov, 2007
10 Nov, 2026
10
30 Oct, 1989
30 Oct, 2008
31 Oct, 2027
11
18 Nov, 1990
18 Nov, 2009
18 Nov, 2028
12
7 Nov, 1991
7 Nov, 2010
7 Nov, 2029
13
26 Oct, 1992
27 Oct, 2011
27 Oct, 2030
14
14 Nov, 1993
14 Nov, 2012
15 Nov, 2031
15
4 Nov, 1994
4 Nov, 2013
4 Nov, 2032
16
24 Oct, 1995
24 Oct, 2014
24 Oct, 2033
17
11 Nov, 1996
12 Nov, 2015
12 Nov, 2034
18
31 Oct, 1997
31 Oct, 2016
1 Nov, 2035
19
19 Nov, 1998
19 Nov, 2017
19 Nov, 2036

The evening before new year in the calendar is called Oìdhche Shamhna (pronounced eech-uh how-nuh), meaning "Night of Samhain", and new year's day is called A' Bhliadhna Ùr (uh vlee-uh-nuh oor), "The New Year".

Dates and the Celtic Count

The Celtic count is a series of four numbers, separated by full stops, denoting the cycle, year, month and day. Optionally, the month name may be added at the end as well, e.g., today's date is 164·18·7·2 Geamhain.

The count can be used to work out the correct sequence of days, months and years in a particular period. Other dates in the Celtic calendar can be worked out here.


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