The Borana

Borana

The Borana Oromo, also called the Boran, are a pastoralist ethnic group living in southern Ethiopia and northern Kenya. They are a moiety of the Oromo people, the other being the Barentu Oromo.-Profile:...

 calendar consist of 29.5 days and 12 months for a total 354 days in a year. It has no weeks. It is a lunar and stellar calendar.

It is believed that the Borana of developed their own calendar around 300 BC. The Borana calendar is a lunar-stellar calendrical system, relying on astronomical observations of the moon in conjunction with seven particular stars or constellations. Borana Months (Stars/Lunar Phases) are Bittottessa (iangulum), Camsa (Pleiades), Bufa (Aldebarran), Waxabajjii (Belletrix), Obora Gudda (Central Orion-Saiph), Obora Dikka (Sirius), Birra (full moon), Cikawa (gibbous moon), Sadasaa (quarter moon), Abrasa (large crescent), Ammaji (medium crescent), and Gurrandala (small crescent).

Days

1. Bita Kara
2. Gardaduma
3. Bita Lama
4. Sonsa
5. Sorsa
6. Rurruma
7. Algajima
8. Lumasa
9. Arb
10. Gidada
11. Walla
12. Ruda
13. Basa Dura
14. Areri Dura
15. Basa Ballo
16. Areri Ballo
17. Carra
18. Adula Dura
19. Maganatti Jarra
20. Adula Ballo
21. Maganatti Britti
22. Garba Dura
23. Salban Dura
24. Garba Balla
25. Salban Balla
26. Garda Dullacha
27. Salban Dullacha

(first two or three days are repeated during the months)

Months can be identified by moon phase in relation to seven stars or star groups. They are Triangulum

Triangulum

Triangulum is a small constellation in the northern sky. Its name is Latin for triangle, and it should not be confused with Triangulum Australe in the southern sky. Its name derives from its three brightest stars, of third and fourth magnitude, which form a nearly isosceles long and narrow triangle...

, Pleiades

Pleiades (star cluster)

In astronomy, the Pleiades, or Seven Sisters , is an open star cluster containing middle-aged hot B-type stars located in the constellation of Taurus. It is among the nearest star clusters to Earth and is the cluster most obvious to the naked eye in the night sky...

, Aldebaran

Aldebaran

Aldebaran is a red giant star located about 65 light years away in the zodiac constellation of Taurus. With an average apparent magnitude of 0.87 it is the brightest star in the constellation and is one of the brightest stars in the nighttime sky...

, Bellatrix, central Orion

Orion (constellation)

Orion, often referred to as The Hunter, is a prominent constellation located on the celestial equator and visible throughout the world. It is one of the most conspicuous, and most recognizable constellations in the night sky...

, Saiph, and Sirius

Sirius

Sirius is the brightest star in the night sky. With a visual apparent magnitude of −1.46, it is almost twice as bright as Canopus, the next brightest star. The name "Sirius" is derived from the Ancient Greek: Seirios . The star has the Bayer designation Alpha Canis Majoris...

star systems.

Months and Star System

1. Bittottessa-Triangulum
2. Camsa-Pleiades
3. Bufa-Aldebarran
4. Wacabajjii-Belletrix
5. Obora Gudda-Central Orion-Saiph
6. Obora Dikka-Sirius
7. Birra-full moon
8. Cikawa-gibbous moon
9. Sadasaa-quarter moon
10. Abrasa-large crescent
11. Ammaji-medium crescent
12. Gurrandala-small crescent