Astronomical Predictions: Exploring the Ramadan Calendar

by Ashas Bukhari

Astronomical Predictions: Exploring the Ramadan Calendar

26 Feb 2024

Muslims have been using the moon to track time for more than a thousand years. While some still follow traditional methods, predicting astronomical events has become more efficient. Countries like Saudi Arabia and the United Arab Emirates have combined tradition and modern technology to calculate the moon's cycles. By using both modern technology and the age-old tradition of observing the moon with the naked eye, these nations have embraced the best of both worlds.

Come along with us as we delve into the world of creating a Ramadan calendar using astronomical predictions.

Following the lunar cycle

The Islamic calendar has 354 days. The length of each month is either twenty-nine or thirty days, depending on the moon’s cycle. Therefore, Ramadan arrives eleven days earlier in each subsequent year of the Gregorian calendar.

Traditionally, moon sightings determine the start and end dates of Ramadan. Islamic scholars and local religious authorities rely on human observations to spot the crescent moon, as is tradition.

The lunar calendar starts a new month upon sighting the moon after the 29th day of the previous month. The moonsighting tradition for Ramadan and the following month of Shawal are particularly lively affairs, with families and communities trying to spot the moon on the 29th of Shaban and Ramadan, respectively.

In later years, the more traditional methods of moon sighting are being supplemented by astronomical predictions. Astronomers use calculations based on the moon's age, altitude, and sunset time to predict the visibility of the crescent moon.

These predictions help determine Ramadan's start and end dates, providing a more standardised approach across different regions. Still, the final say always lies with the official committees appointed to see the moon.

Photo: Nousnou Iwasaki

Understanding astronomical conditions

Astronomers consider several key factors when calculating Ramadan's start and end dates. The age of the moon is one of them. This refers to the number of days since the last new moon was sighted. The moon's age indicates its phase and a new moon marks the beginning of a new lunar month.

Here’s a good guide by Al Jazeerah for a more visual representation, showcasing the phases of the moon and how the moon's height above the horizon determines its altitude in the calculation. A higher altitude increases the chances of visibility.

Additionally, the sunset time plays an important role, as it affects the visibility of the crescent moon. By analysing these factors, astronomers can make predictions about when the moon will be visible, helping to determine the dates of the Ramadan calendar.

The role of technology

Advancements in technology have greatly improved the accuracy of predicting the beginning and ending of Ramadan. With the help of sophisticated instruments and computer algorithms, astronomers can analyse data more precisely and make more accurate calculations. High-resolution telescopes and advanced software allow detailed observations of the moon's position and phase.

Moreover, access to precise astronomical data and global communication networks enables experts to collaborate and share information, leading to more accurate predictions. These advancements have significantly enhanced our understanding of celestial events, like the visibility of the crescent moon, making the Ramadan calendar more precise and consistent.

In observatories across the Arab world, scientists and amateur astronomers came together to search for the new moon, signalling the beginning of the sacred month of Ramadan.

Professors at Cairo’s National Institute for Astronomy and Geophysics lead the search for the Ramadan crescent using scientific and mathematical methods, observing the moon's appearance, prayer times, eclipses, and Qibla direction through a telescope. Meanwhile, scientists at Saudi Arabia’s Majmaah University Astronomical Observatory employ CCTV cameras to monitor the sunset and detect the new moon promptly.

The official announcement from Saudi Arabia's Supreme Court confirms the sighting of Ramadan, signalling the beginning of the new month.

In Damascus, observers atop the Syrian Astronomical Association's building look for the Ramadan moon every year.

The tradition of moonsighting, utilised for centuries, remains vital in determining the start of Ramadan according to the lunar-based Islamic calendar.

Moon sighting in Saudi Arabia

A team composed of a Qada member, an astronomer from KACST, a representative from the Amarah Governing Council, and local volunteers forms Saudi Arabia's numerous Hilal sighting committees. Utilising sophisticated telescopes and astronomical calculations like those from a moon tracker run by the United Kingdom’s Nautical Almanac Office, Crescent Moon Watch, this committee determines the sighting of the crescent moon.

In a 2023 interview with Al Arabiya, Abdullah al-Khudairy, the director of the observatory at Majmaah University in Hautat Sudair, recognised as one of the most prominent and relied-upon moon-sighters in the kingdom, explained why the Saudi government relies on moon sighting committees.

Khudairy told Al Arabiya that they do not simply adhere to everything said or written about the sighting; instead, they engage in research, practical application, and comprehensive field observations. He expressed their goal of disseminating precise astronomical knowledge, believing that everyone is earnestly endeavouring to preserve this tradition.

The Saudi government picked Hautat Sudair city, nestled in a quaint village where Riyadh, Sudair, and Qassim intersect, about 140 kilometres north of Riyadh, as the centre for moonsighting. A team of astronomy professors spent six months selecting a spot southwest of the city. The selected area stands out for its rocky, hilly landscape with little wind and a height ranging from 780 to 930 metres above sea level, far from any pollution.

Khudairy believes there's no distinction between academic astronomers with expertise in astronomy and the seers, as both rely on scientific and astronomical principles.

He mentioned that the number of seers in Saudi Arabia is growing across various regions.

At the Majmaah University observatory, there are over 13 cooperative seers. The observatory offers a range of specialised services, including astronomical calculations, Hijri calendars, Qibla direction, Ramadan calendars, and more.

Moon sighting in the UAE

Sharia courts across the country will keep track of and report any sightings to the committee. Meanwhile, the Lunar Calendar Committee at the Abu Dhabi Judicial Department will search for evidence and share their findings with the Moon-sighting committee.

Although moon-sighting efforts are commonly undertaken throughout the UAE, not all succeed in spotting the crescent.

Ultimately, the decision rests with the Abu Dhabi Judicial Department, which gathers reports from across the nation.

While Saudi Arabia typically takes the lead in announcing the start and end of Ramadan in the region, each country has its own committee to verify the sighting of the new moon.

Photo: Jim Harris

Criteria for moonsighting

Observatories adhere to specific criteria when it comes to moonsighting. Firstly, they look for the conjunction, signifying the moon's new phase or birth, which must have occurred in the region. Additionally, they require a moonset after sunset, with the moon lingering on the horizon for at least 20 minutes. Finally, they assess the moon's visibility to the naked eye or with optical aids.

These criteria, widely adopted by various moon sighting organisations, prioritise an astronomical and calculation-based approach over solely relying on direct eye sightings. This approach not only aligns with Shariah principles but also allows for accurate predictions of the start of the Islamic month, including sacred months. Moreover, it fosters inclusivity by involving observatories from multiple Muslim countries, promoting unity among Muslims worldwide.

The simplicity and accuracy of this criterion make it an attractive method for determining the beginning of the Islamic month. Despite past conflicts and debates, embracing a scientific and calculated approach can lead to greater unity and harmony within the Muslim community.

Astronomical predictions offer a universal framework for determining Ramadan dates, ensuring consistency across different regions and communities. This consistency facilitates the planning and organisation of religious activities, such as fasting, prayers, and community events, while promoting better coordination among Muslims worldwide. Additionally, it enables individuals and communities to prepare adequately for Ramadan, fostering reliability and uniformity in its observance.

Different regions may have varying sighting criteria for determining Ramadan's start, influenced by factors such as the visibility of the crescent moon, its altitude, and the duration between sunset and moonset. Local traditions, cultural practices, and religious interpretations play a significant role in shaping these criteria, reflecting the diversity within the Muslim community and its rich tapestry of cultural practices.

by Ashas Bukhari