MUHAMMADIYAH.OR.ID, YOGYAKARTA — Muhammadiyah Central Board’s Council for Religious Opinion and Reform provided a detailed explanation for its decision to set the first day of Ramadan 1447 Hijri on Wednesday, February 18, 2026. The determination follows the Unified Global Hijri Calendar, known as Global Unified Hijri Calendar (Kalender Hijriah Global Tunggal/KHGT).
The explanation was delivered by Rahmadi Wibowo, a member of the council, during a religious lecture on Wednesday (28/01).
Rahmadi explained that KHGT is built on a core principle: one day and one date across the entire world. This principle, he said, can only function if the earth is treated as a single matla’, or calendrical zone, without regional divisions, while still adhering to the International Date Line.
“If the earth is divided into separate calendrical zones, uniformity becomes impossible,” Rahmadi said. “One region could already enter a new date, while another remains on the previous day.”
For that reason, KHGT adopts the concept of ittihad al-mathali’, or global unity of horizons. It uses global parameters rather than local or regional criteria.
Rahmadi emphasized that any calendar system must rely on astronomical calculation (hisab). Moon sighting (rukyah), he said, can only confirm the beginning of a single month and therefore cannot produce a structured calendar for long-term planning.
“A calendar, by definition, must be predictable,” he explained. “Without calculation, you cannot build a reliable system of timekeeping.”
Astronomical Criteria under KHGT
Under Muhammadiyah’s ruling, a new Hijri month begins simultaneously worldwide if, before 24.00 GMT, at least one land area on earth meets two astronomical conditions:
- a minimum moon-sun elongation of eight degrees; and
- a minimum crescent altitude of five degrees at sunset.
If these primary criteria are not met before midnight GMT, additional parameters apply:
- First, lunar conjunction (ijtimak) must occur in New Zealand before dawn, since it is the earliest inhabited region to welcome a new day.
- At the same time, the elongation and altitude criteria must be fulfilled somewhere on land in the Americas, which mark the end of the global 24 hours cycle.
“Dawn is used because it defines the beginning of fasting,” Rahmadi said. “This ensures no region is left behind or moves ahead of the global calendar.”
Astronomical Findings for Ramadan 1447 Hijri
Based on astronomical calculations, lunar conjunction occurred on Tuesday, February 17, 2026, at 12:01:09 GMT. However, until midnight GMT, no land area directly met the eight-degree elongation and five-degree altitude requirements. As a result, the primary criteria were not satisfied.
The council then applied the secondary parameters. In February, New Zealand observes daylight saving time (UTC+13), meaning the conjunction occurred at approximately 1 a.m. local time, before dawn. This satisfied the first condition.
Next, calculations showed that in Bethel, Alaska, the crescent moon exceeded both the elongation and altitude thresholds. According to Rahmadi, this fulfilled the global requirement.
“Even though the area is small and sparsely populated, it remains valid,” he said. “The reference point is land, not population size.”
Global Application, Regardless of Local Visibility
Rahmadi stressed that under KHGT, the visibility of the crescent in Indonesia does not determine the start of the month. Data showed that at that time, the crescent remained below the horizon in Indonesia, Mecca, and Turkey.
“Had we still relied on local crescent visibility, Indonesia would have begun Ramadan on February 19,” he said. “However, because KHGT applies global unity, fulfillment in Alaska is transferred worldwide.”
He noted that this approach resembles the earlier concept of “transfer of visibility,” but KHGT applies it globally rather than within national boundaries.
Based on the full sequence of calculations and criteria, Muhammadiyah’s Majelis Tarjih formally set the first day of Ramadan 1447 Hijri on Wednesday, February 18, 2026.
Rahmadi concluded his explanation by expressing hope that Muslims would reach Ramadan in good health and complete the month in devotion.
“May we all be granted the opportunity to welcome Ramadan and observe it fully until the end,” he said.
Translator: Bintang Adrian
