Akan calendar each Akan year tends to be the various yam festivals celebrated around August or September. The lunar cycle and 28-day month are not carefully observed, except by the coastal Akan who are interested in tides as they affect fishing. Still, the month is known as "bosome". It consists of 28 days rather than the 30 or 31 days of the Gregorian calendar. Three "bosome" make two Adaduanan. Since the arrival of Swiss missionaries from Basel in the early nineteenth century, Christian Akan scholars have tended to 'Akanize' the Roman calendar rather than observe, analyse and explain the Akan calendar based
Lunar calendar to produce a lunisolar calendar. A 49-month cycle was proposed as the basis of an alternative Easter computation by Isaac Newton around 1700. The tabular Islamic calendar's 360-month cycle is equivalent to 24×15 months, minus a correction of one day. Lunar calendar A lunar calendar is a calendar based upon the monthly cycles of the Moon's phases (synodic months), in contrast to solar calendars, whose annual cycles are based only directly upon the solar year. The most commonly used calendar, the Gregorian calendar, is a solar calendar system that originally evolved out of a lunar calendar system. A purely lunar