MUHAMMADIYAH.OR.ID, YOGYAKARTA — The proposed unified global hijri calendar has garnered various criticisms, with some raising concerns about its potential conflict with scientific principles and the practice of rukyat (observing the crescent moon). Critics argue that the single global hijri calendar could lead to certain regions entering a new month while the crescent moon remains invisible, while other regions might have to wait until the following day despite the crescent moon being visible a day earlier.
One of the main criticisms surrounding the unified global hijri calendar is the possibility of a region being forced to start a new Islamic month while the crescent moon is still below the horizon. According to the Prophet Muhammad (PBUH), Muslims are instructed to “liru’yatihi or see the crescent moon” to mark the beginning of a new month. If the crescent moon is below the horizon and cannot be observed, enforcing the start of a new month under such circumstances would contradict the Sunnah.
Responding to these concerns, the Chairperson of Muhammadiyah Syamsul Anwar emphasized that the unified global hijri calendar is designed to adhere to two fundamental requirements. First, it must not prevent any region from entering a new month if it has fulfilled the imkanu rukyat (visibility criteria of 5-8 degrees) anywhere on Earth. Second, it must not compel any region to begin a new month before conjunction (the meeting of the sun and moon) has occurred.
The unified global hijri calendar aims to ensure fairness by preventing regions in the westernmost part of the world from being forced to delay the start of a new month simply to wait for the crescent moon to become visible in eastern regions. Conversely, it also prevents eastern regions from being pressured into starting a new month before conjunction has taken place.
“These two conditions are fundamental. The unified global hijri calendar cannot be implemented if these conditions are not met,” said Syamsul on Wednesday (July 10).
The unified global hijri calendar proposes to address the challenge of the crescent moon’s potential invisibility in certain regions through a concept called “transferring imkan rukyat.” This concept acknowledges that individuals in western regions, like those in the United States, have a higher chance of sighting the crescent moon on the first day of its appearance. In contrast, individuals in far-eastern regions, such as New Zealand, are less likely to see the crescent moon on the first day. To address this disparity, the unified global hijri calendar incorporates “transferring imkan rukyat.”
Transferring imkan rukyat involves sharing the results of rukyat observations or the imkan rukyat itself from one location to another location that has not yet conducted rukyat or experienced imkan rukyat. This principle is applied globally to ensure that eastern regions are not forced to start a new month before the occurrence of ijtimak (conjunction), as mandated by the Quran in Surah Yasin verse 39.
Syamsul further explained that transferring imkan rukyat is not a new practice in Indonesia. For example, if the crescent moon is visible in western Indonesia but remains below the horizon in eastern Indonesia, the eastern region still follows the start of the new month based on the western observation. This demonstrates that transferring imkan rukyat is not an issue, but rather a practical and effective solution that has already been implemented to maintain uniformity in determining the beginning of hijri months.
Muhammadiyah welcomes all forms of criticism and encourages open discussions. However, the organization recommends that critics first thoroughly examine the unified global hijri calendar concept, which has been widely disseminated through various channels. By gaining a comprehensive understanding of the unified global hijri calendar, any criticism offered will be more constructive and grounded in knowledge.