Another calendrical system was developed around 300 BC by the Oromo people. A lunar-stellar calendar, this Oromo calendar relies on astronomical observations of the moon in conjunction with seven particular stars or constellations. Oromo 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).