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Islamic Calendar
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The Islamic Calendar begins on the Hijra: July 19, 622 CE of the Gregorian Calendar, the day the prophet Muhammed traveled from Mecca to Medina. Each year in the Islamic Calendar consists of 12 months. Odd months have 30 days while even months have 29 days. On leap years, the final month is extended to 30 days. Leap years occur during years 2, 5, 7, 10, 13, 16, 18, 21, 24, 26 and 29 of a 30-year cycle. Thus, every 30 years, there are 19 normal years with 354 days and 11 years with 355 days.
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The Islamic Calendar starts from the Hijra, which is when Prophet Muhammad pbuh migrated from Makkah to Madinah. This is why Islamic dates have the suffix AH (After Hijra). The Calendar is based on a lunar cycle and has twelve months. These months begin at sunset, when the new moon is sighted. The lunar year is approximately 354 days long. The names of Islamic months are as follows:
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The Islamic Calendar, which is based purely on lunar cycles, was first introduced in 638 C.E. by the close companion of the Prophet (PBUH) and the second Caliph, `Umar ibn Al-KHaTTab (592-644 C.E.) RAA. He did it in an attempt to rationalize the various, at times conflicting, dating systems used during his time. `Umar consulted with his advisors on the starting date of the new Muslim chronology. It was finally agreed that the most appropriate reference point for the Islamic calendar was the Hijrah. The actual starting date for the Calendar was chosen (on the basis of purely lunar years, counting backwards) to be the first day of the first month (1 MuHarram) of the year of the Hijrah.
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The Islamic Calendar, used by Muslims, is based on the moon. It has 12 months of either 29 or 30 days. Eleven times, every 30 years, an extra day is added to keep the calendar in time with the moon, not the seasons.
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Islamic Calendar