Extended Abstract
Introduction:
The Hijri lunar calendar has been based on the motion of the Moon in its orbit and astronomical calculations, in accordance with the geographical locations of its inhabitants, since its inception. As Islamic acts of worship, including Laylat al-Qadr (the Night of Decree), are tied to specific dates in this calendar, and given Muslims’ strong commitment to these prescribed acts of worship, the need for precise determination of lunar calendar dates and times becomes even more critical. The significance and spiritual status of Laylat al-Qadr among Muslims have led believers to seek its exact time in order to benefit from its blessings. According to Islamic hadiths and narrations, the most probable nights for Laylat al-Qadr are the 19th, 21st, 23rd, and 27th nights of Ramadan, especially the 23rd night. There is no doubt that Laylat al-Qadr is a single night throughout the world that occurs in the last ten nights of Ramadan; however, due to the Earth’s rotation, when it is night in one part of the world, it is day in another, and thus not all regions of the Earth experience night simultaneously. The aim of this research is to identify an appropriate method for considering a single Laylat al-Qadr for people in different parts of the world, given the problem of the non-simultaneity of night across the globe.
Materials and Methods
Some Quranic interpreters, such as Ayatollah Naser Makarem Shirazi, believe that Laylat al-Qadr lasts for 24 hours, since one complete rotation of the Earth can extend the shadow or darkness of night over all regions of the globe. This view and theory may help justify a single Laylat al-Qadr (the Night of Decree) for the entire Earth; however, it does not specify the exact starting time of Laylat al-Qadr on the Earth. In this paper, based on religious, astronomical, and geographical data, a new theory is proposed to determine the start time of Laylat al-Qadr and define its probable time interval. This time interval is considered to begin at sunset (more precisely: the religious time of the Maghrib call to prayer) in the first location on the Earth where the crescent moon of Ramadan is sighted with the naked eye, and to end 24 hours later. Accordingly, points to the east of this location, share their night with the first location of crescent visibility worldwide, while points to the west of this location, gradually enter their night and fall entirely within the time frame of Laylat al-Qadr. In other words, eastern locations will experience an incomplete part of their night during the time frame of Laylat al-Qadr.
Results
First, we analyzed the newly proposed theory for the time frame of Laylat al-Qadr during Ramadan 1447 AH in Iran and globally, presenting the results in various maps using HP3-Planet software. Then, we studied and calculated this new theory over a long period of 228 years, from Ramadan 1448 AH to Ramadan 1675 AH. For this purpose, we conducted a geographical-astronomical analysis for three locations in Iran (northern, central, and southern at latitudes 36°, 32°, and 28° N, respectively) and the city of Mecca, in Saudi Arabia, based on five main criteria for starting lunar Calendar months. These criteria are: (1) positive lag time of the moon after conjunction with the sun, (2) sharing and overlap during part of the night, (3) sharing and overlap during most of the night, (4) possibility of lunar crescent sighting with optical aids, and (5) possibility of lunar crescent sighting with the naked eye. To determine the first location on Earth where the crescent moon is visible to the naked eye, we used the reliable and Safed criterion from the South African Astronomical Observatory (SAAO visibility criteria). Precise calculations were performed using MATLAB coding, and the results were organized into maps, charts, and tables.
Discussion and Conclusion
After reviewing the results tables from the 228-year period and calculating the annual average Laylat al-Qadr time frame for the five mentioned criteria, we found that Criterion 3, Criterion 2, Criterion 4, Criterion 5, and finally Criterion 1, in that order, showed the highest conformity with the Laylat al-Qadr time frame at the first global crescent sighting location, as well as the highest annual average duration. This analysis produced the same ranking of criteria across the three Iranian latitudes (northern, central, and southern) and in Mecca city. Therefore, a key outcome of this research is that Criterion 3, the “Unity of Horizons” (Jurisprudential-religious term: Ittihad al-Aafaq) with the condition of “sharing most of the night,” is the best fit for determining the start of lunar calendar months. Conversely, the “positive lag time of the moon” criterion (i.e., the moonset occurring after sunset), or the criterion used by Saudi Arabia’s Umm al-Qura calendar, was identified as the least compliant with the time frame of Laylat al-Qadr during Ramadan. Furthermore, this new theory may help reconcile differences and discrepancies in the criteria for commencing lunar calendar months. Consequently, even if two different criteria for starting a lunar month differ by one day, Laylat al-Qadr would still occur for both groups, although the duration of the night might be shorter for one group than for the other.