Understanding MABIMS Criteria: Why Hilal Below 3 Degrees is Definitely Rejected?

The determination of the start of the Hijriah month in Indonesia, such as Ramadan, Syawal, and Zulhijah, now refers to strict scientific standards. These criteria are known as the MABIMS Criteria, a regional agreement between the Ministers of Religious Affairs of Brunei Darussalam, Indonesia, Malaysia, and Singapore. This criteria did not emerge out of nowhere. Based on modern astronomical research and global observation data, a hilal below 3 degrees in height is very difficult to distinguish from the background light of the sky (syafak). Meanwhile, an elongation of 6.4 degrees refers to the physical limit for the moon’s crescent to have sufficient light intensity to be observed by the human eye or optical aids. With the implementation of these criteria, when will Eid 2026 be? If on the day of observation the hilal’s position by calculation (hisab) is still below 3 degrees or the elongation is below 6.4 degrees, then the running month (for example, Ramadan) will most likely be completed to 30 days (istikmal). This is done even if there are claims of seeing the hilal, as such reports will be re-verified against the agreed visibility criteria.