OPTIMASI KRITERIA KALENDER ISLAM TERPADU BERDASARKAN POSISI MATAHARI DAN BULAN MENGGUNAKAN ALGORITMA MEEUS; OPTIMIZATION OF THE CRITERIA OF INTEGRATED ISLAMIC CALENDAR BASED ON SUN AND MOON POSITIONS USING MEEUS ALGORITHM

Akhyar, Andi Muh, Rinto Anugraha NQZ

2015 | Disertasi | FMIPA UGM

Almost every year, a difference in the determination of Islamic months occurs in Indonesia, especially in the relation with fasting, Idul Fitri and pilgrimage. One of the main source of the difference is there is no agreement of criterion of Islamic months in Indonesia. The objective of this paper is to optimize the Islamic calendar criterions based on sun and moon positions using Meeus algorithm. The criterion have a strong relation with astronomical events such as newmoon phase, sunset, moonset, and their positions at set. Optimization of Islamic calendar criteria is done using several parameter such as month age duration, parameter of alternating duration, and the minimum numbers of three and four consecutive month with the same duration. This research is expanded for 10 cities in the world and for a reference conducted especially for the beginning of Zulhijah month for 20 years (1431-1450H). According to the research, the criterion for altitude difference 1o is the best criterion of international Islamic calender.

Kata Kunci : Islamic calender criteria; Sun and moon positions; Meeus Algorithm