It is not uncommon for neighbouring countries to have differences in determining the start of Ramadan or Syawal.

Since the time of the companions, differences in determining the beginning of Islamic (Hijri) months have existed among various regions and countries. This diversity is a natural aspect of life as decreed by Allah s.w.t, provided it does not contradict the fundamental principles of religion.

Like a work of art, its beauty lies in the harmony of diverse colours and patterns, rather than mere uniformity.

MABIMS and Criteria for Determining the Beginning of the Hijri Month

MABIMS (Informal Meeting of the Ministers of Religious Affairs of Brunei, Indonesia, Malaysia and Singapore) facilitates regional cooperation on various religious matters. Through this partnership, member countries work together to enhance religious understanding and strengthen community development across the region.

One key achievement is the establishment of the Imkanur Rukyah MABIMS Criteria for determining the visibility of new crescent moons, that marks the beginning of Hijri months such as Ramadan and Syawal. 

If the crescent moon meets the established criteria at Maghrib on the 29th day of a Hijri month, the following day will be declared the beginning of the new Hijri month.

However, if it does not meet the criteria, the next day will be regarded as the last concluding day of the month. This is based on the Imkanur Rukyah (possibility of sighting) Criteria, which determines when the crescent moon is considered unobservable, whether by the naked eye or through a telescope.

The latest MABIMS criteria outline two key parameters for determining the visibility of the crescent moon on the 29th day of a Hijri month at sunset. First, the elongation (angular distance) between the sun and the moon must be at least 6.4 degrees. Second, the altitude of the crescent moon must be no less than 3 degrees above the horizon.

What is the basis for the MABIMS criteria?

One of the primary references for these criteria is the research conducted by astronomer Mohammad Shawkat Odeh. His study is based on 737 observations of the crescent moon from various locations worldwide, conducted without the aid of imaging devices such as CMOS cameras or charge-coupled devices (CCD).

The findings indicate that, in all 737 recorded observations, there has never been a case where the crescent moon was visible to the naked eye or through a telescope when the elongation (angular distance) between the sun and the moon was less than 6.4 degrees.

Singapore’s Approach

While MABIMS members are in agreement on the Imkanur Rukyah Criteria, Singapore faces unique challenges in moon sighting due to our geographical and atmospheric conditions. Limited viewing space and consistently cloudy weather make the physical observation of the crescent moon particularly difficult. As a result, Singapore has adopted the Hisab (calculation) method since 1974 to determine the beginning of Hijri months, including Ramadan, Syawal, and Zulhijjah.

The Hisab method determines the start of the new Hijri month based on the MABIMS Criteria. If the crescent moon is calculated to be visible on the 29th day, the next day marks the beginning of the new month. If the moon is not visible, the month is extended to 30 days.

Unlike other MABIMS countries that use these criteria as guidelines for physical moon sighting (rukyah), Singapore directly applies them through calculations (Hisab).

Each MABIMS member country has the sovereign right to determine its preferred method—whether Hisab or rukyah (sighting)—based on its specific context and circumstances. While Singapore employs Hisab and other neighbouring countries practice sighting, both approaches are religiously valid and share the same objective: to accurately determine Islamic months using established principles. This reflects the flexibility of Islamic practice in accommodating different contexts while maintaining religious authenticity.

Analysis of the Crescent Moon for Ramadan 1446H

To clarify further, let's consider an example from Ramadan 1446H. According to the calculations in Singapore, the data for the crescent moon on the 29th of Sha'ban 1446H at Maghrib is expected to be as follows: (i) elongation: 5.1 degrees and (ii) altitude of the crescent moon: 4.3 degrees.

Based on the principles outlined earlier, this means that on the 29th of Sha'ban, the crescent moon will not be visible because it does not meet the two established parameters. Therefore, the next day, 1 March 2025, will be considered as the 30th day for the month of Sha'ban in Singapore.

However, the declaration of the beginning of Ramadan is still subject to the announcement by the Mufti of Singapore, commonly made in the evening of 29th Sha’aban .

By analysing the crescent moon data for neighbouring countries such as Malaysia, we find that on the 29th of Sha'ban, the crescent moon will have the following: (i) elongation: 5.3 degrees and (ii) altitude of the crescent moon: 4.3 degrees.

Based on the MABIMS Criteria and the calculations of the Department of Survey and Mapping Malaysia (JUPEM), the new moon is not expected to be visible in Malaysia, either with the naked eye or through a telescope.

Therefore, the beginning of Ramadan 1446H for both Singapore and Malaysia is expected to begin simultaneously on 2 March 2025.

Efforts undertaken by the Singapore Islamic Astronomy Committee (Falak Committee)

The Falak Committee, established under the MUIS Fatwa Committee, plays a crucial role in determining Singapore's Islamic calendar. As part of its responsibilities, the Committee actively engages regional authorities, exchanging expertise and findings to ensure the accurate determination of Hijri months.

In 2024, the Committee met with the Jabatan Mufti Johor and the Department of Islamic Development Malaysia (JAKIM), where preliminary calculations indicated that Ramadan 1446H would begin on 2 March 2025 for both countries, as the crescent moon would not be visible either by the naked eye or through a telescope.

However, Malaysia's official announcement will only be made on 28 February 2025, following their rukyah observations, in line with their established practice.

Respect the Decisions of Each Country

The variation in determining Hijri months has been a normal occurrence in both Islamic tradition and Singapore's history. More important than these differences are the principle of maintaining community cohesion through respect for national sovereignty and adherence to local religious authority ('Ulil Amri).

It is important to note that these determinations are not made lightly; they are based on scholarly considerations and authentic religious principles.

Scan the QR code below or visit go.gov.sg/falak-sg to read more on ‘Navigating Tradition and Science – Singapore’s Approach in Determining the Hijri Calendar’

Watch this street interview video on Falak Syari'i (Islamic Astronomy) !

The author is Deputy Mufti Ustaz Dr. Izal Mustafa Kamar. This article first appeared on Berita Harian.

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