Muhammadiyah Sets Ramadan 2026 Start Date Based on Astronomical Data from Alaska
Indonesia’s Muhammadiyah organization has announced that Ramadan 1447 H will begin on Wednesday, February 18, 2026. The decision, based on the organization’s adherence to the Single Global Hijriyah Calendar (KHGT), has sparked discussion regarding the use of astronomical parameters observed in Alaska as a reference point.
Understanding the Global Calendar Approach
Muhammadiyah’s determination is rooted in the KHGT, established at a 2016 international congress in Turkey. This calendar utilizes parameters requiring a minimum height of 5 degrees and an elongation of 8 degrees for recent moon visibility. These parameters were first met in Alaska, leading to the February 18th date.
The KHGT views the Earth as a single time dimension, with the day cycle beginning at the International Date Line and moving westward. If the new moon’s visibility parameters are met anywhere on Earth before the end of the day’s cycle, it is considered legally valid for all Muslims globally. This approach acknowledges that the conditions for the new moon’s existence are met in Alaska, making it a valid starting point for the calendar, even for those in distant locations like Indonesia.
Aligning with Established Practices
Muhammadiyah points out that the concept of using an international date line is not new to Islamic practice. The timing of Friday prayers, which sequentially move from the Pacific region westward, serves as a precedent. Muslims globally accept this sequential timing without question, demonstrating an existing acceptance of a global time framework for religious observance.
Shariah Principles and Global Unity
The KHGT applies the principle of Ittihadul Mathali’ (unity of place of publication) on a global scale. Previously, Muhammadiyah jurisprudence recognized the concept of Wilayatul Hukmi, where a new moon sighting in one locality could determine the start of fasting for a region. The KHGT expands this to encompass the entire Earth, termed Wilayatul Ardh. This is achieved through a process called naql imkan al-rukyah, or transferring the visibility of the new moon globally.
Muhammadiyah interprets the Prophet Muhammad’s command, “Speedy when you see it,” as a call to Muslims as a unified global community. If the new moon is accessible according to sharia and astronomy in one part of the world (like Alaska), that obligation extends to the entire ummah.
Addressing Concerns About “Retroactive” Fasting
Concerns about fasting before the new moon is visible in Alaska are addressed by emphasizing the certainty provided by astronomical calculations (hisab). The reckoning system relies on the certainty of an event occurring, rather than immediate physical observation. Indonesia’s earlier time zone means that the legal basis for fasting is established in the morning, based on the certainty that the new moon will meet the required parameters in Alaska later in the day.
Convergence with the Ummul Qura Calendar
Muhammadiyah notes that their determination aligns with the likely decision of the Ummul Qura calendar (Saudi Arabia), which uses looser criteria for new moon visibility. On the evening of February 17th in Mecca, the moon was above the horizon, indicating the start of the new moon according to their criteria. Muhammadiyah’s emphasis on Alaska stems from its commitment to the stricter criteria established at the 2016 International Congress for Calendar Unification.
A Long-Term Ijtihad Effort
The implementation of the KHGT is the result of nearly two decades of intellectual effort by Muhammadiyah, beginning with a 2007 international symposium initiated by then-General Chairperson Prof. Dr. Din Syamsuddin. The system was officially adopted in 2025, with Ramadan 1447 AH marking its first implementation.
Muhammadiyah views the transition to a global calendar as a step towards unifying the Muslim community and addressing a long-standing need for a consistent and universally accepted calendar system.