Muslims are having a tradition of following lunar calendar and not the solar calendar. One cannot justify the date of Eid-UL-Fitr for the year as it changes from year to year and cannot be similar to the previous year. As Reported, In lunar Calendar the year is 11 to 12 days shorter than the solar year and so the days and dates of Eid-UL-Fitr would not be similar every year.
When the Crescent moon which is also known as Hilal is sighted , the beginning of Ramadan which is the ninth month of the Islamic calendar is decided. Muslims celebrate Ramadan only after observing hilal, the crescent moon. When the moon is sighted at night, the first day of Ramadan and its fasting begins from the next day.
Similarly, When Hilal or the crescent moon is sighted again at the end of the Ramadan month, Eid-UL-Fitr Celebration starts and Muslims indulge in the celebration of Eid-UL-Fitr day with utmost joy and happiness. The beginning of the new month Shawwal which is the tenth month of Islamic Calendar starts when the Hilal or the crescent moon is sighted .The Sight of this semi-circled moon marks the beginning of Eid-UL-Fitr .
A number of factors affect the sighting of the crescent moon. Detecting the Eid Moon is not an easy task. Thus, it is recommended that the number of observers should be involved in the sighting of the correct crescent moon especially in cases where the naked eyes are being used .
There are some factors which affect the sight of the crescent moon :