Global Hijriyah Calendar As Challenges Fikih Astronomy

Unification of hijri calendar occupies very important position because the calendar system adopted as symbol of civilization, particularly for Islamic civilization which no enter the era of 1.5 millennium and has not global calendar system. The hijri calendar system is lunar calendar based on the circulation of the moon around the earth. In astronomical science, the movement of the moon from new month to the next can be calculated carefully and accurately so that the demands of the predictable calendar system can be fulfilled. The discourse of the hijri calendar in the Islamic world is closely related to the use of method in determining the beginning of the lunar month. Todays, there are two methods used by Muslims in determining the beginning of the month, the method of Hisab and Rukyat. The method of hisab is predictable and its accordance with the calendar is also predictable, while the rukyat method is nonpredictable, bringing the correlation between two methods that challenge astronomical jurisprudence. This is because the Hijri calendar does not only serve the accuracy of administrative affairs but also establish the timeliness of the worshiping time.