The Islamic, or Hijri, calendar, is a lunar calendar, i.e. it is based upon the cycles of the Moon. However, it differs from other lunar calendars, such as the Hebrew and Chinese calendars, in that those calendars are “luni-solar”, i.e. they follow the lunar cycles but also keep their years synchronised with the tropical year by inserting periodically and extra month.
The Islamic calendar, however, is purely lunar and therefore does not keep its years synchronised with the solar year. Instead it always has 12 months, and no additional months are added to adjust it to the solar year. As a result, the months move forward from one Gregorian year to the next. So for instance, the month of Ramadan may occur in the autumn in a particular year, but after a few years it will have moved into the summer. This will keep happening until, eventually, it is back in the autumn again.
The months do not have pre-determined lengths, as each new month traditionally begins upon the first sighting of the new crescent moon at sunset. The months of the calendar are shown in the following table.
The important events in the Islamic year occur on specific dates. The most prominent of these are:
- Al-Hijra – Islamic New Year, occurring on the 1st day of the 1st month, Muharram. It marks the end of Mohammad’s journey from Mecca to Medina.
- Milad un Nabi – the Prophet’s birthday. Celebrated on the 12th or 17th day of the 3rd month, Rabi’al-Awwal.
- Ramadan. This is the ninth month of the year and is marked by fasting during daylight hours for the entire month. The festival of Eid ul-Fitr marks the end of the month when fasting is over.
- Hajj. This is an annual pilgrimage of Muslims to Mecca in Saudi Arabia, the holiest city in the Islamic faith. It occurs during a 10-day period from the 1st to the 10th day of the 12th month, Dhu al-Hijjah.
- Eid ul-Adha – the Festival of Sacrifice. This is a four day holiday marking the sacrifice of Abraham. It also highlights the end of the annual pilgrimage to Mecca, called Hajj. Prayers are held at the mosque followed by an evening feast.