Ramadan, the ninth month of the Islamic lunar calendar, can be 29 or 30 days long. An Islamic month begins with the sighting of the new crescent in the western horizon, immediately after sunset. Muslims look toward the western horizon for the new moon on the 29th day of Sha'ban, the eighth month. If the new moon is sighted, Ramadan has begun with the sunset but fasting begins with the next dawn. If the new moon is not sighted on this 29th day, Muslims complete 30 days of Sha'ban (the previous month) and Ramadan begins the following day.