I'm not sure were I came across this, but felt like it belong here, I have linked the pdf if you guys want to read more about it.
The Somali Calendar: An Ancient, Accurate Timekeeping System By Said M-Shidad Hussein
1. Introduction The Somalis use both solar and lunar calendric systems. The Lunar year, in which months correspond to the phases of the moon, is approximately 354.37 days. The months of the lunar year systematically shift with respect to the cycle of the seasons. The lunar calendar is used for religious observations as well as social, economic, and legal contracts. It is commonly used throughout Muslim world. The solar calendar is used for purposes such as weather forecasting, maritime travel, and identification of the seasons. This paper focuses exclusively with the solar calendar (Amin-tiris or Taqwiim1 ).
Although unfamiliar to most of the rest of the world,2 the Somali solar calendar is one of the most fascinating, sophisticated and accurate calendars in the world.3 Its evolution probably dates from approximately 2,500 years ago, or even earlier. Although farming and herding have historically been the leading economic activities of Somalia, it is also known as a mercantile nation. Experiences and needs from these three communities, particularly the last two, have contributed to the formation of the solar calendar.
The Somali solar year, which is a tropical year in fact, corresponds to the cycle of the seasons.4 It is based on the weekly cycle and upon the sun, and it is organized into four seasons, twelve months, and 52 weeks plus one day or 365 days. The New Year, which is characterized by a festival called ‘Dabshid’5 falls on or around July 20, in the Gregorian calendar. Other periodic cycles are derived from the weekly cycle in order to create a calendrical year and to extend the timekeeping system beyond. As a result, various time units are established. This extended system is based on the number of ‘seven.’
2. Rules of the Somali Calendar 2.1. Rules Overview Besides the weekly cycle, there are four other major cycles in the system: the 50-day cycle, which is seven weeks plus one day; the yearly cycle which is 7 x 50 days plus 15 days; the seven-year cycle which is 7 x 365 or 2,555 days long; and the 49-year cycle which is 7 x 7 years in length. All these time units share the number of ‘seven’ or weekly cycle. Every unit is named after its first day, which is also the last day of yearly and 50-day cycles.
For example, the first 50 days of the Somali Calendric Year of 2007-2008, in the Gregorian system, are from Saturday July 21, 2007, to Saturday Sep. 8, 2007. The same pattern applies to the first and the last days of the year, while the first day of the year is Saturday July 21, 2007, the last day of the year is Saturday July 19, 2008, because this calendar is based on the summer solstices. Thus, the time units used in this year are 50 day intervals and 365 day intervals, and the name of this year is Saturday. These time units are carefully and systematically enumerated day by day and period by period where practice and redundancy have resulted in sophistication and accuracy.
2.2. Determining the Length of the Year Since the yearly cycle depends on the 50-day and the weekly cycles, these three cycles are primary units of the system. Its length is determined by them. Let us take our Saturday year of 2007-2008 as an example: the first 50 days of this year are also called Saturday period. Consequently, the next 50 days are Sunday period. The remaining periods of the cycles follow the weekdays order. But, the total of the days in the cycles are 350 or 50 weeks. So that, in order to organize a year, and to allow the succeeding years to follow the order, two weeks and one day must be added to this number which results in 365 days. The following chart shows what we have said in words.
The Somali Calendar: An Ancient, Accurate Timekeeping System By Said M-Shidad Hussein
1. Introduction The Somalis use both solar and lunar calendric systems. The Lunar year, in which months correspond to the phases of the moon, is approximately 354.37 days. The months of the lunar year systematically shift with respect to the cycle of the seasons. The lunar calendar is used for religious observations as well as social, economic, and legal contracts. It is commonly used throughout Muslim world. The solar calendar is used for purposes such as weather forecasting, maritime travel, and identification of the seasons. This paper focuses exclusively with the solar calendar (Amin-tiris or Taqwiim1 ).
Although unfamiliar to most of the rest of the world,2 the Somali solar calendar is one of the most fascinating, sophisticated and accurate calendars in the world.3 Its evolution probably dates from approximately 2,500 years ago, or even earlier. Although farming and herding have historically been the leading economic activities of Somalia, it is also known as a mercantile nation. Experiences and needs from these three communities, particularly the last two, have contributed to the formation of the solar calendar.
The Somali solar year, which is a tropical year in fact, corresponds to the cycle of the seasons.4 It is based on the weekly cycle and upon the sun, and it is organized into four seasons, twelve months, and 52 weeks plus one day or 365 days. The New Year, which is characterized by a festival called ‘Dabshid’5 falls on or around July 20, in the Gregorian calendar. Other periodic cycles are derived from the weekly cycle in order to create a calendrical year and to extend the timekeeping system beyond. As a result, various time units are established. This extended system is based on the number of ‘seven.’
2. Rules of the Somali Calendar 2.1. Rules Overview Besides the weekly cycle, there are four other major cycles in the system: the 50-day cycle, which is seven weeks plus one day; the yearly cycle which is 7 x 50 days plus 15 days; the seven-year cycle which is 7 x 365 or 2,555 days long; and the 49-year cycle which is 7 x 7 years in length. All these time units share the number of ‘seven’ or weekly cycle. Every unit is named after its first day, which is also the last day of yearly and 50-day cycles.
For example, the first 50 days of the Somali Calendric Year of 2007-2008, in the Gregorian system, are from Saturday July 21, 2007, to Saturday Sep. 8, 2007. The same pattern applies to the first and the last days of the year, while the first day of the year is Saturday July 21, 2007, the last day of the year is Saturday July 19, 2008, because this calendar is based on the summer solstices. Thus, the time units used in this year are 50 day intervals and 365 day intervals, and the name of this year is Saturday. These time units are carefully and systematically enumerated day by day and period by period where practice and redundancy have resulted in sophistication and accuracy.
2.2. Determining the Length of the Year Since the yearly cycle depends on the 50-day and the weekly cycles, these three cycles are primary units of the system. Its length is determined by them. Let us take our Saturday year of 2007-2008 as an example: the first 50 days of this year are also called Saturday period. Consequently, the next 50 days are Sunday period. The remaining periods of the cycles follow the weekdays order. But, the total of the days in the cycles are 350 or 50 weeks. So that, in order to organize a year, and to allow the succeeding years to follow the order, two weeks and one day must be added to this number which results in 365 days. The following chart shows what we have said in words.
