bgkalendar v0.0.6
Welcome to the Bulgarian Calendar Project
Table of Contents generated with Markdown-TOC
- Java Library
- PHP Library and Web Site
- Gregorian and Julian Calendar
- Ancient Bulgarain Calendar Principles
- License
What is the Ancient Bulgarian Calendar
There have been lots of researches regarding how Ancient Bulgarians have measured times and the researches showed that there has been an Ancient Bulgarian calendar which has been (according to most researchers) solar based.
This project aims to provide a library and a web-site for calculation of the current year, month and day according to the assumptive Ancient Bulgarian calendar.
Calculation is based on some assumptions. For example when does the calendar begin. When is day 1, month 1 from year 1, and others.
This calendar and library is not to be assumed an extensive research or the final source of truth at all.
Please feel free to obtain/use/modify the code according to your own research.
Java Library
Please get more information here.
PHP Library and Web Site
Under the phpsite sub-directory, you can find a PHP version of the library.
That makes it easy to use that library in your own PHP Web site.
We also have a sample site with a main page phpsite/index.php and some css
styling and so on. Look at the phpsite/kalendar-en.php
for an explanation of the principles of the calendar.
Sample of this site has been installed on http://bgkalendar.com.
Gregorian and Julian Calendar
Although the primary goal of the project was to calculate the current date based on the Ancient Bulgarian calendar, it has been designed in a generic and extendable way, so it in fact provides an API and a framework for calculating the date on any calendar (not even just solar based calendars).
Then 3 implementations on top of this API interface has been implemented:
- Implementation of the Julian calendar
- Implementation of the Gregorian calendar (the modern calendar used in European countries)
- Implementation of the Ancient Bulgarain calendar.
Ancient Bulgarain Calendar Principles
The Bulgarian calendar is the calendar of the ancient Bulgarians restored from
written historical data
Nominalia of the Bulgarian khans
and the folk tales and legends.
There are studies of various scholars who sometimes quite differ in
conclusions reached.
Beginning of the Calendar
Most researchers accept the starting point on the 22-nd day of the winter solstice (December 21) during the year 5505 BC – in other words, we can assume that the first year of the Bulgarian calendar coincides almost completely with 5504 BC in the Gregorian calendar.
+---------------------------------------+------------------------------+
| .. 20 21 22 23 24 25 26 27 28 29 30 31| 1 2 3 4 5 6 7 8 9 10 11 ... |
+-------^-------------------------------+------------------------------+
| December 5505 yr. before Christ | January 5504 yr. before Ch. |
+-------^-------------------------------+------------------------------+
|
|
+-------------------------------------------------------------+
|1 2 3 4 5 6 7 8 9 10 11 12 ... |
+-------------------------------------------------------------+
| First Month of the First year of Ancient Bulgarian Calendar |
+-------------------------------------------------------------+
^
|
|
Winter Solar solsticeWhen doing calculations and comparison with the Gregorian and/or Julian calendar, please bare in mind that in both Julian and Gregorian calendars there is no zero year - that is to say, that 1-st year BC is immediately followed by the 1-st year after Christ.
+---------------------------------------+------------------------------+
| .. 20 21 22 23 24 25 26 27 28 29 30 31| 1 2 3 4 5 6 7 8 9 10 11 ... |
+---------------------------------------+------------------------------+
| December 1-st year BC | January 1 year AC |
+---------------------------------------+------------------------------+In our calendar model, we have adopted for the start of the calendar to be a year earlier. So 21-st of December 5506 BC (Monday according to the Grigorian calendar) was adopted as the first day of the Bulgarian calendar.
Structure of the year
According to researchers, the year has been divided into 12 months + one or two (in leap years)
business days, which were beyond the months. Months were grouped in quarters of 3 months.
First month of each quarter always had 31 days * , and the remaining two months had 30 days.
So each quarter, there are exactly 91 days or 364 days that makes for four quarters.
At the end of the year (or at the beginning according to some researchers) there has been
one additional day that is outside months and was called Eni.
The analogue of the day Eni is today's Ignazhden (St. Ignatius day), also called ednazhden.
Counting the day Eni, the year had already 365 days. Similar to the Julian and Gregorian
calendar once on every 4 years additional leap day (midsummer day) was added based on some rules,
which we would reviw further on. The leap day (midsummer day), just like the day Eni was beyond any month.
It was put after the end of the 6-th month, before the start of the 7-th month.
The leap day was called Behti. The analogue of the Midsummer day is today's Enyovden .
In our model the conditional Behti is represented as the last 31-st day in the 6-th month only on leap years, Eni is represented as the last 31-st day in the 12-th month.
YEAR
First Month Second Month Third Month
I II III IV V VI VII I II III IV V VI VII I II III IV V VI VII
1 2 3 4 5 6 7 1 2 3 4 1 2
8 9 10 11 12 13 14 5 6 7 8 9 10 11 3 4 5 6 7 8 9
Q1 15 16 17 18 19 20 21 12 13 14 15 16 17 18 10 11 12 13 14 15 16
22 23 24 25 26 27 28 19 20 21 22 23 24 25 17 18 19 20 21 22 23
29 30 31 26 27 28 29 30 24 25 26 27 28 29 30
Forth Month Fifth Month Sixth Month
I II III IV V VI VII I II III IV V VI VII I II III IV V VI VII
1 2 3 4 5 6 7 1 2 3 4 1 2
8 9 10 11 12 13 14 5 6 7 8 9 10 11 3 4 5 6 7 8 9
Q2 15 16 17 18 19 20 21 12 13 14 15 16 17 18 10 11 12 13 14 15 16
22 23 24 25 26 27 28 19 20 21 22 23 24 25 17 18 19 20 21 22 23
29 30 31 26 27 28 29 30 24 25 26 27 28 29 30
Day Behty (31-st) - only on leap years
Sevent Month Eight Month Nineth Month
I II III IV V VI VII I II III IV V VI VII I II III IV V VI VII
1 2 3 4 5 6 7 1 2 3 4 1 2
8 9 10 11 12 13 14 5 6 7 8 9 10 11 3 4 5 6 7 8 9
Q3 15 16 17 18 19 20 21 12 13 14 15 16 17 18 10 11 12 13 14 15 16
22 23 24 25 26 27 28 19 20 21 22 23 24 25 17 18 19 20 21 22 23
29 30 31 26 27 28 29 30 24 25 26 27 28 29 30
Tenth Month Eleventh Month Twelveth Month
I II III IV V VI VII I II III IV V VI VII I II III IV V VI VII
1 2 3 4 5 6 7 1 2 3 4 1 2
8 9 10 11 12 13 14 5 6 7 8 9 10 11 3 4 5 6 7 8 9
Q4 15 16 17 18 19 20 21 12 13 14 15 16 17 18 10 11 12 13 14 15 16
22 23 24 25 26 27 28 19 20 21 22 23 24 25 17 18 19 20 21 22 23
29 30 31 26 27 28 29 30 24 25 26 27 28 29 30
Day Eni (31-st)It is assumed that the days Eni and Behti, are not counted as days of a week. These are the so-called days which are not «not counted». Without them, the rest of the days that count, form exactly 52 weeks. So if the year begins on Monday, the next year will also begin on Monday and each calendar date remains fixed forever in a specific day of the week.
Some researchers suggest that Bulgarian week began with Sunday. Basis for such an
assumption is the name of a day Wednesday - sryada - that means in Bulgarian 'middle' (of the week).
An alternative assumption is that Monday was widely adopted as the first day of the week.
The grounds for such an alternative assumption are the names of the following days: Tuesday (vtornik),
Thursday (chetvartak) and Friday (petak) - meaning, respectively, second, fourth and fifth (day of the week) - in bulgarian
sekond - vtori, fourth - chetvarti, fifth - peti. That is to say if Tuesday is the second day,
then Monday is supposed to be the first. In our model, we accept contingent names of days of the week -
1-st, 2-nd, 3-rd, 4-th, 5-th, 6-th and 7-th.
In the table above, we have represented them with the latin numbers (I, II, III, IV, V, VI, VII) to destinguish them from the days of the month.
In any case, the days of the week do not match to the days of the week that we know from the modern Gregorian calendar. This is because in the modern calendar, there are no days that are not counted and are not included in the composition of the week. As we said in the Bulgarian calendar, such days are Eni and Behti.
*: There are also hypotheses, that the first and second month of each quarter had 30 days, but the third had 31 days.
Common across all hypotheses is that the year is divided into quarters of 91 days.
Cycles for correction of the calendar
Tropical Earth year - that is the time for which the Earth makes one complete lap around the Sun, equals 190 419 365.242 Earth days - that is to say 365 days, 5 hours, 48 minutes and 45.5 seconds. So in a calendar year of 365 days, it goes faster with a quarter day (5 hours, 48 minutes and seconds 45.5) each year. After four years, the calendar year is starting approximately 1 day before completing the astronomical round of the Earth around the Sun.
To stay in sync, the calendar year need to be corrected by adding a leap day every four years - the so-called day Behti that is added at the end of the 6th month. This adjustment, however, is not sufficient because the high gain of the calendar was not exactly a day (24 hours). It is 23 hours, 15 minutes and 2 seconds. So after adding the leap day the calendar begins to lag.
This requires a system of additional adjustments. This system divides the calendar into periods, as shown below.
Four year period
Every forth year has an additional leap day named Behti at the end of the 6-th month. A year with a leap day would be called a leap year. An year without a leap day would be called a non-leap year.
+----------------+-----------------+---------------+-----------------+
| First Non Leap | Second Non Leap | Thir Non Leap | *Fourth LEAP* |
| Year | Year | Year | *Year* |
+----------------+-----------------+---------------+-----------------+Twelve year period
Three four - year periods form one 12 year period. This period is not characterized by a calendar adjustment, but what makes it specila is that each year from the 12 year cycle has an animal assigned to it - that is why this 12 year cycle is also called animalian cycle. Various researchers adopt different order of animals, as well as different starting animal. The names of the animals are also controversial. Here are some examples:
+---------------------------------------------------------------------------------------------+
| According To |
+-------------------------+---------------------------------------------+---------------------+
| Georgi Krustev | Yordan Vulchev | Petur Dobrev |
+-------------------------+---------------------------------------------+---------------------+
| animal | name(s) | animal | name(s) | animal | name(s) |
+--------------+----------+--------------+------------------------------+----------+----------+
| Pig | Dox | Pig | dox, dok, prase | |
+--------------+----------+--------------+------------------------------+---------------------+
| Mouse | Karan | Mouse | somor, shushi | Mouse | Somor |
+--------------+----------+--------------+------------------------------+----------+----------+
| Ox | Shegor | Ox | shegor, kuvrat, buza, busman | Ox | Shegor |
+--------------+----------+--------------+------------------------------+----------+----------+
| Snow Leopard | Barus | Tiger | bars, parus, barus | - | |
+--------------+----------+--------------+------------------------------+----------+----------+
| Rabbit | Dvan | Rabbit | dvansh | Rabbit | Dvan |
+--------------+----------+--------------+------------------------------+----------+----------+
| Dragon | Hala | Dragon-Snake | ver, dragun, kala, slav | Dragon | Ver |
+--------------+----------+--------------+------------------------------+----------+----------+
| Snake | | Snake | dilom, delyan, attilla | Snake | Dilom |
+--------------+----------+--------------+------------------------------+----------+----------+
| Horse | Tag | Horse | tek, tag, tih, alasha | Horse | Teku |
+--------------+----------+--------------+------------------------------+----------+----------+
| Monkey | Pisin | Monkey | pesin, pisin | - | - |
+--------------+----------+--------------+------------------------------+----------+----------+
| Ram | | Ram | suruh, sever, rasate | - | - |
+--------------+----------+--------------+------------------------------+----------+----------+
| Cock | Tox | Cock | toh, tah | Cock | Toh |
+--------------+----------+--------------+------------------------------+----------+----------+
| Dog | Et-h | Dog | et-h | Dog | Et-h |
+--------------+----------+--------------+------------------------------+----------+----------+
| Boar | Dohs |
+----------+----------+Each 12-year period has been either male or female. In a male period - all years within this period were male - the corresponding animals have been male. In a female period - all years within the period comply with the animals of the female sex. After each male 12 year period, a female one follows. After that a mail period again and so on...
Sixty year period (star day)
A period of 60 years equals exactly to 5 twelve-year cycles or 15 four-year cycles. It was conventially called "star day" Yordan Vulchev. Since the 60-year cycle is multiple of 4 year periods, then it, generally, ends in a leap year. Such a star day would be called - a leap star day.
In certain cases, for the correction of the calendar, the leap day of the last year in the 60 year period neet to be taken away. In such case, we will call the star day a non leap star day.
Leap Star Day NON Leap Star Day
+-------+--------------+------+---------------+ +-------+--------------+------+----------------+
| BLACK | Four Yrs: 1 | № 1. | Non leap year | | BLACK | Four Yrs: 1 | № 1. | Non leap year |
| | | № 2. | Non leap year | | | | № 2. | Non leap year |
| | | № 3. | Non leap year | | | | № 3. | Non leap year |
| | | № 4. | Leap year | | | | № 4. | Leap year |
| |-------------------------------------+ | |--------------------------------------+
| | Four Yrs: 2 | № 5. | Non leap year | | | Four Yrs: 2 | № 5. | Non leap year |
| | | № 6. | Non leap year | | | | № 6. | Non leap year |
| | | № 7. | Non leap year | | | | № 7. | Non leap year |
| | | № 8. | Leap year | | | | № 8. | Leap year |
| |-------------------------------------+ | |--------------------------------------+
| | Four Yrs: 3 | № 9. | Non leap year | | | Four Yrs: 3 | № 9. | Non leap year |
| | | № 10.| Non leap year | | | | № 10.| Non leap year |
| | | № 11.| Non leap year | | | | № 11.| Non leap year |
| | | № 12.| Leap year | | | | № 12.| Leap year |
+---------------------------------------------+ +----------------------------------------------+
| RED | Four Yrs: 4 | № 13.| Non leap year | | RED | Four Yrs: 4 | № 13.| Non leap year |
| | | № 14.| Non leap year | | | | № 14.| Non leap year |
| | | № 15.| Non leap year | | | | № 15.| Non leap year |
| | | № 16.| Leap year | | | | № 16.| Leap year |
| |-------------------------------------+ | |--------------------------------------+
| | Four Yrs: 5 | № 17.| Non leap year | | | Four Yrs: 5 | № 17.| Non leap year |
| | | № 18.| Non leap year | | | | № 18.| Non leap year |
| | | № 19.| Non leap year | | | | № 19.| Non leap year |
| | | № 20.| Leap year | | | | № 20.| Leap year |
| |-------------------------------------+ | |--------------------------------------+
| | Four Yrs: 6 | № 21.| Non leap year | | | Four Yrs: 6 | № 21.| Non leap year |
| | | № 22.| Non leap year | | | | № 22.| Non leap year |
| | | № 23.| Non leap year | | | | № 23.| Non leap year |
| | | № 24.| Leap year | | | | № 24.| Leap year |
+---------------------------------------------+ +----------------------------------------------+
| Y | Four Yrs: 7 | № 25.| Non leap year | | Y | Four Yrs: 7 | № 25.| Non leap year |
| E | | № 26.| Non leap year | | E | | № 26.| Non leap year |
| L | | № 27.| Non leap year | | L | | № 27.| Non leap year |
| L | | № 28.| Leap year | | L | | № 28.| Leap year |
| O |-------------------------------------+ | O |--------------------------------------+
| W | Four Yrs: 8 | № 29.| Non leap year | | W | Four Yrs: 8 | № 29.| Non leap year |
| | | № 30.| Non leap year | | | | № 30.| Non leap year |
| | | № 31.| Non leap year | | | | № 31.| Non leap year |
| | | № 32.| Leap year | | | | № 32.| Leap year |
| |-------------------------------------+ | |--------------------------------------+
| | Four Yrs: 9 | № 33.| Non leap year | | | Four Yrs: 9 | № 33.| Non leap year |
| | | № 34.| Non leap year | | | | № 34.| Non leap year |
| | | № 35.| Non leap year | | | | № 35.| Non leap year |
| | | № 36.| Leap year | | | | № 36.| Leap year |
+---------------------------------------------+ +----------------------------------------------+
| BLUE | Four Yrs: 10 | № 37.| Non leap year | | BLUE | Four Yrs: 10 | № 37.| Non leap year |
| | | № 38.| Non leap year | | | | № 38.| Non leap year |
| | | № 39.| Non leap year | | | | № 39.| Non leap year |
| | | № 40.| Leap year | | | | № 40.| Leap year |
| |-------------------------------------+ | |--------------------------------------+
| | Four Yrs: 11 | № 41.| Non leap year | | | Four Yrs: 11 | № 41.| Non leap year |
| | | № 42.| Non leap year | | | | № 42.| Non leap year |
| | | № 43.| Non leap year | | | | № 43.| Non leap year |
| | | № 44.| Leap year | | | | № 44.| Leap year |
| |-------------------------------------+ | |--------------------------------------+
| | Four Yrs: 12 | № 45.| Non leap year | | | Four Yrs: 12 | № 45.| Non leap year |
| | | № 46.| Non leap year | | | | № 46.| Non leap year |
| | | № 47.| Non leap year | | | | № 37.| Non leap year |
| | | № 48.| Leap year | | | | № 48.| Leap year |
+---------------------------------------------+ +----------------------------------------------+
| WHITE | Four Yrs: 13 | № 49.| Non leap year | | WHITE | Four Yrs: 13 | № 49.| Non leap year |
| | | № 50.| Non leap year | | | | № 50.| Non leap year |
| | | № 51.| Non leap year | | | | № 51.| Non leap year |
| | | № 52.| Leap year | | | | № 52.| Leap year |
| |-------------------------------------+ | |--------------------------------------+
| | Four Yrs: 14 | № 53.| Non leap year | | | Four Yrs: 14 | № 53.| Non leap year |
| | | № 54.| Non leap year | | | | № 54.| Non leap year |
| | | № 55.| Non leap year | | | | № 55.| Non leap year |
| | | № 56.| Leap year | | | | № 56.| Leap year |
| |-------------------------------------+ | |--------------------------------------+
| | Four Yrs: 15 | № 57.| Non leap year | | | Four Yrs: 15 | № 57.| Non leap year |
| | | № 58.| Non leap year | | | | № 58.| Non leap year |
| | | № 59.| Non leap year | | | | № 59.| Non leap year |
| | | № 60.| *Leap year* | | | | № 60.| *Non leap year*|
+---------------------------------------------+ +----------------------------------------------+Actually the only difference between the leap star day and non-leap star day is in the last year - the 60-th year.
In the leap star day it is a leap year. In the non-leap star day it is not.
Each star day is split into 5 12 year periods. Each of these periods has been assigned an element, a corresponding color and direction.
The five elements/colors/directions are:
Element Color Direction
1. Water BLACK Center
2. Fire RED South
3. Earth YELLOW West
4. Tree BLUE North
5. Metal WHITE East
Each of the 5 12-year periods, is considered either male or female in an alternating sequence. Star day, which begins with the male 12-year period, will be called male, and one that begins with the female 12-year period would be called female. Within two consecutive star days (120 years), we can find all of the possible combinations of element, sex and animal. So the combination of element, sex and animal can be used to identify a date within a 120-year period.
Element SEX Years
+--------------------------------------------------------------------------------+
| I. Water MALE 1 2 3 4 5 6 7 8 9 10 11 12 |
MALE | II. Fire FEMALE 13 14 15 16 17 18 19 20 21 22 23 24 |
STAR | III. Earth MALE 25 26 27 28 29 30 31 32 33 34 35 36 |
YEAR | IV. Tree FEMALE 37 38 39 40 41 42 43 44 45 46 47 48 |
| V. Metal MALE 49 50 51 52 53 54 55 56 57 58 59 60 |
+--------------------------------------------------------------------------------+
| VI. Water FEMALE 61 62 63 64 65 66 67 68 69 70 71 72 |
FEMALE | VII. Fire MALE 73 74 75 76 77 78 79 80 81 82 83 84 |
STAR | VIII. Earth FEMALE 85 86 87 88 89 90 91 92 93 94 95 96 |
YEAR | IX. Tree MALE 97 98 99 100 101 102 103 104 105 106 107 108 |
| X. Metal FEMALE 109 110 111 112 113 114 115 116 117 118 119 120 |
+--------------------------------------------------------------------------------+Four hundred and twenty year period (STAR WEEK)
When we group 7 star days (each consisting of 60 years), we receive an amount of 420 years,
which we call a star week.The first, third and fifth star days in each star week are always non-leap star days.
The second, fourth and sixth are always leap.
The seventh Star day in general is also leap, but when there is a need for further correction in the calendar, it is replaced by a non-leap one.
A star week in which the last star day is non-leap, will be called - non-leap. Similarly if the last star day is leap, the whole star week
would be called - leap.
LEAP STAR WEEK NON-LEAP STAR WEEK
years days years days
1. Non-Leap star day: 60 21 914 1. Non-Leap star day: 60 21 914
2. Leap star day: 60 21 915 2. Leap star day: 60 21 915
3. Non-Leap star day: 60 21 914 3. Non-Leap star day: 60 21 914
4. Leap star day: 60 21 915 4. Leap star day: 60 21 915
5. Non-Leap star day: 60 21 914 5. Non-Leap star day: 60 21 914
6. Leap star day: 60 21 915 6. Leap star day: 60 21 915
7. Leap star day: 60 21 915 7. Leap star day: 60 21 914
Total: 420 153 402 Total: 420 153 401
Some researchers call the first star day - "Star Monday", the second - "Star Tuesday" etc..., while others are starting from "Star Sunday". In our research that is unimportant and in the table above we have indicated them just with the numbers from 1 to 7. Each star week consists of 420 Earth years. The difference between a non leap leap and leap star week is only in the last start day. The leap star week ends on a leap star day, which in its turn means that this star day (60 years) ends on a leap year. Conversely, the non-leap star week ends on non-leap star day, which in turn means that this star day (60 years) ends on a non-leap year.
Star month
Like the weeks on Earth are grouped stars in a month, the same way every 4 star weeks are grouped in a star month. So one star month equals 1 680 Earth years. Star month could also be a "leap" or "non leap". Here is its structure in both cases.
LEAP STAR MONTH
Sequential number of star day Years Days
-----------------------------
Leap star week 1 2 3 4 5 6 7 420 153 402
Non-Leap star week 8 9 10 11 12 13 14 420 153 401
Leap star week 15 16 17 18 19 20 21 420 153 402
Leap star week 22 23 24 25 26 27 28 420 153 402
Total: 1 680 613 607
NON LEAP STAR MONTH
Sequential number of star day Years Days
-----------------------------
Leap star week 1 2 3 4 5 6 7 420 153 402
Non-Leap star week 8 9 10 11 12 13 14 420 153 401
Leap star week 15 16 17 18 19 20 21 420 153 402
Non-Leap star week 22 23 24 25 26 27 28 420 153 401
Total: 1 680 613 606Star year
Twelve star months form a so-called star year. Star year consists of exactly 20 160 Earth years. Sixth star month of the star year is always non leap. The other star months except the last month are always leap. The last star month is generally leap but can be non leap if further adjustment to the calendar is needed. To understand when such correction happens, see the description of star age.
STRUCTURE OF LEAP STAR YEAR
Star Month 1 LEAP Star Month 2 LEAP Star Month 3 LEAP
I II III IV V VI VII I II III IV V VI VII I II III IV V VI VII <-- Sequential
number of
1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 7 Star Day
8 9 10 11 12 13 14 8 9 10 11 12 13 14 8 9 10 11 12 13 14
15 16 17 18 19 20 21 15 16 17 18 19 20 21 15 16 17 18 19 20 21
22 23 24 25 26 27 28 22 23 24 25 26 27 28 22 23 24 25 26 27 28
Star Month 4 LEAP Star Month 5 LEAP Star Month 6 NON-LEAP <-- NON-LEAP
I II III IV V VI VII I II III IV V VI VII I II III IV V VI VII <-- Sequential
number of
1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 7 Star Day
8 9 10 11 12 13 14 8 9 10 11 12 13 14 8 9 10 11 12 13 14
15 16 17 18 19 20 21 15 16 17 18 19 20 21 15 16 17 18 19 20 21
22 23 24 25 26 27 28 22 23 24 25 26 27 28 22 23 24 25 26 27 28
Star Month 7 LEAP Star Month 8 LEAP Star Month 9 LEAP
I II III IV V VI VII I II III IV V VI VII I II III IV V VI VII <-- Sequential
number of
1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 7 Star Day
8 9 10 11 12 13 14 8 9 10 11 12 13 14 8 9 10 11 12 13 14
15 16 17 18 19 20 21 15 16 17 18 19 20 21 15 16 17 18 19 20 21
22 23 24 25 26 27 28 22 23 24 25 26 27 28 22 23 24 25 26 27 28
Star Month 10 LEAP Star Month 11 LEAP Star Month 12 LEAP
I II III IV V VI VII I II III IV V VI VII I II III IV V VI VII <-- Sequential
number of
1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 7 Star Day
8 9 10 11 12 13 14 8 9 10 11 12 13 14 8 9 10 11 12 13 14
15 16 17 18 19 20 21 15 16 17 18 19 20 21 15 16 17 18 19 20 21
22 23 24 25 26 27 28 22 23 24 25 26 27 28 22 23 24 25 26 27 28
STRUCTURE OF NON-LEAP STAR YEAR
Star Month 1 LEAP Star Month 2 LEAP Star Month 3 LEAP
I II III IV V VI VII I II III IV V VI VII I II III IV V VI VII <-- Sequential
number of
1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 7 Star Day
8 9 10 11 12 13 14 8 9 10 11 12 13 14 8 9 10 11 12 13 14
15 16 17 18 19 20 21 15 16 17 18 19 20 21 15 16 17 18 19 20 21
22 23 24 25 26 27 28 22 23 24 25 26 27 28 22 23 24 25 26 27 28
Star Month 4 LEAP Star Month 5 LEAP Star Month 6 NON-LEAP <-- NON-LEAP
I II III IV V VI VII I II III IV V VI VII I II III IV V VI VII <-- Sequential
number of
1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 7 Star Day
8 9 10 11 12 13 14 8 9 10 11 12 13 14 8 9 10 11 12 13 14
15 16 17 18 19 20 21 15 16 17 18 19 20 21 15 16 17 18 19 20 21
22 23 24 25 26 27 28 22 23 24 25 26 27 28 22 23 24 25 26 27 28
Star Month 7 LEAP Star Month 8 LEAP Star Month 9 LEAP
I II III IV V VI VII I II III IV V VI VII I II III IV V VI VII <-- Sequential
number of
1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 7 Star Day
8 9 10 11 12 13 14 8 9 10 11 12 13 14 8 9 10 11 12 13 14
15 16 17 18 19 20 21 15 16 17 18 19 20 21 15 16 17 18 19 20 21
22 23 24 25 26 27 28 22 23 24 25 26 27 28 22 23 24 25 26 27 28
Star Month 10 LEAP Star Month 11 LEAP Star Month 12 NON-LEAP <-- NON-LEAP
I II III IV V VI VII I II III IV V VI VII I II III IV V VI VII <-- Sequential
number of
1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 7 Star Day
8 9 10 11 12 13 14 8 9 10 11 12 13 14 8 9 10 11 12 13 14
15 16 17 18 19 20 21 15 16 17 18 19 20 21 15 16 17 18 19 20 21
22 23 24 25 26 27 28 22 23 24 25 26 27 28 22 23 24 25 26 27 28
Each star year consists of 48 weeks star. That equals exactly 336 star days (every star day consisting of 60 Earth years). Thus, each star year consists of 20 160 Earth years. Within a leap star year there are always exactly 7 363 283 (seven million, three hundred and sixty-three thousand, two hundred eighty-three) Earth days. Within a non leap star year there are always exactly 7 363 282 earth days.
Period of 4 star years
Star years just like earth years are grouped in fours. In general, only the second star year is a non leap year. From the rest - the first, the third and the fourth are leap. However when there is a need of correction to he calendar, all the four star years are leap. To understand when that happens, please see section for star epoch. Every period of 4 star years consists of just 80 640 Earth years. The usual non-leap period of 4 star years (when the second star year is non-leap, and the other star years are leap) consists of 29 453 131 earth days. The leap period of 4 star years (when all the four star years are leap due to the need for correction) consists of 29 453 132 earth days.
NON-LEAP PERIOD OF
4 STAR YEARS
(80 640 EARTH YEARS)
years days
1. Leap star year: 20 160 7 363 283
2. Non-Leap star year: 20 160 7 363 282
3. Leap star year: 20 160 7 363 283
4. Leap star year: 20 160 7 363 283
total: 80 640 29 453 131
LEAP PERIOD OF
4 STAR YEARS
(80 640 EARTH YEARS)
years days
1. Leap star year: 20 160 7 363 283
2. Leap star year: 20 160 7 363 283
3. Leap star year: 20 160 7 363 283
4. Leap star year: 20 160 7 363 283
total: 80 640 29 453 132 Star Epoch
Star epoch is the last and greatest period in the Bulgarian calendar. That period completes the correction of the calendar, so this period does not have a leap and non-leap variants. It consists of 125 periods of 4 star years, or exactly 500 star years. All the periods of 4 star years are non leap (which means that the second star year is non leap and the first, the third and the fourth star years are leap), with the exception of the 63-rd period of 4 star years. It is leap, which means, that all its 4 star years are leap.
That is to say that star year with number 250 is leap.
Each star epoch consists of 10 080 000 (ten million and eighty thousand) Earth years, or exactly 3 681 641 376 (three billion, six hundred eighty-one million, six hundred Forty-one thousand, three hundred seventy-six) Earth days.
1 2 3 4 5 6 7 8 9 10
001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020 021 022 023 024 025 026 027 028 029 030 031 032 033 034 035 036 037 038 039 040
11 12 13 14 15 16 17 18 19 20
041 042 043 044 045 046 047 048 049 050 051 052 053 054 055 056 057 058 059 060 061 062 063 064 065 066 067 068 069 070 071 072 073 074 075 076 077 078 079 080
21 22 23 24 25 26 27 28 29 30
081 082 083 084 085 086 087 088 089 090 091 092 093 094 095 096 097 098 099 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120
31 32 33 34 35 36 37 38 39 40
121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160
41 42 43 44 45 46 47 48 49 50
161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200
51 52 53 54 55 56 57 58 59 60
201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240
61 62
241 242 243 244 245 246 247 248
63
249 250 251 252 <--- 63-rd period of 4 star years is the only in the star epoch when all its star years are leap star years.
64 65
253 254 255 256 257 258 259 260
66 67 68 69 70 71 72 73 74 75
261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300
76 77 78 79 80 81 82 83 84 85
301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340
86 87 88 89 90 91 92 93 94 95
341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380
96 97 98 99 100 101 102 103 104 105
381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420
106 107 108 109 110 111 112 113 114 115
421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460
116 117 118 119 120 121 122 123 124 125
461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500