Introduction:
Earth is the third planet from the Sun in the solar system and is part of a vast network of celestial movements. It follows an elliptical orbit around the Sun, completing one full revolution in approximately 365.25 days, which defines a year. In addition to orbiting the Sun, Earth also rotates on its own axis once every 24 hours, creating the cycle of day and night. Apart from orbiting the Sun, Earth is also part of the Earth-Moon system, as the Moon orbits Earth approximately once every 27.3 days. As the moon rotates around the earth, different parts of it are illuminated by the sun and so its shape visible to those on earth varies. These changing appearances are referred to as phases of the moon. These range from the appearance of a crescent, gradually increasing to a semi-circle and then a full circle, known as ‘waxing’, followed by the gradual reduction of the full circle back to a semi-circle and then to a crescent again, known as ‘waning’. These phases repeat every 29.5 days. Even though the orbit is completed in about 27 days, the phases take longer because while the Moon orbits Earth, Earth is also moving around the Sun. As the Earth moves, the Moon has to travel a bit farther to catch up and complete its phase cycle, which is why it takes about 29.5 days for the Moon to go through all its phases.1
The ‘new moon phase’ occurs when the Moon is positioned between the Earth and the Sun, causing the side of the Moon that faces Earth to be completely dark. During this phase, the Moon is not visible from Earth (also known as the ‘dark moon phase’) because the sunlight is shining on the far side of the Moon, away from our view. This marks the beginning of a new lunar cycle, and the Moon will gradually move out of this position, transitioning into the waxing crescent phase as more of its illuminated side becomes visible.
The new moon reflects a celestial phenomenon known as lunar conjunction. This refers to the exact alignment of the Earth, Moon, and Sun, where the Moon is directly between the Earth and the Sun. During this alignment, it is impossible for the Moon to be sighted in the sky. After the lunar conjunction occurs, the dark side of the moon is gradually exposed to sunlight and in these early stages, although the Moon cannot always be seen with the human eye, it is possible to sight it using advanced technological aids.
It is this precise stage, the first potential sighting of the moon after it leaves lunar conjunction that is of particular importance to Muslims, as it marks the beginning of each lunar month in the Islamic (Hijri) calendar, which is used for religious observances. The most significant events tied to moon sighting include Ramadan, Eid al-Fitr, Eid al-Adha, and Hajj. Since Islamic rituals are time-sensitive, knowing the exact start of the month ensures that acts of worship align with divine instructions and that religious obligations have been fulfilled and discharged accurately.
Accuracy in these matters helps maintain religious discipline, strengthens the unity of the Muslim community, and allows individuals to plan their daily lives accordingly. In many Muslim-majority countries, governments and religious councils oversee moon sighting, while in Western nations, communities may follow different rulings, sometimes causing local differences.
The issue of moon sighting remains controversial due to a variety of interpretations of what constitutes the beginning of a new Islamic month and how it is determined. Some scholars argue that physical sighting with the eyes is a prophetic tradition and should not be abandoned, while others advocate for astronomical calculations and other optical aids, consistent with the technological advances of our time. This disagreement has led to situations where Muslims in the same country or even the same city start Ramadan or celebrate Eid on different days. Additionally, cloudy weather can sometimes make moon sighting difficult, further complicating matters. Despite efforts by Islamic organisations to unify moon sighting criteria, differences persist, leading to ongoing discussions about the best way to determine the Islamic calendar in the modern world.
This has led to the following questions:
- Should the new moon be sighted with the human eye or is it sufficient to use telescopes or other technological aids to sight the new moon?
- Can astronomical calculations, rather than physical sighting of the moon determine the start of the new month?
- Should the new moon be sighted in an individual’s place of residence/region for him/her to determine the beginning of the new Islamic month, or can it be visible anywhere in the world?
ICCI Majority Opinion:
The beginning of a new Islamic month can be determined after lunar conjunction has occurred and the Moon facing Earth is exposed to direct sunlight, meaning it is out of the dark Moon phase. This is as soon as the first photons of light originating from the sun are reflected from the Moon to Earth. The visibility of the new Moon does not have to be physically sighted (either with the naked eye or any other technological aid) from Earth, rather astronomical calculations that determine the precise time and date of the Moon emerging from the shadow of the earth, i.e., the first sliver of the first crescent, are sufficient to determine the beginning of a new Islamic month.
Justifications for Majority Opinion:
1. The Holy Quran does not prescribe a detailed method of how to determine the beginning of a new Islamic month, stating only in the context of the commencement of the Islamic month of Ramadan:
“Whomsoever among you witnesses the month [of Ramadan], then let them fast”. 2
2. Narrations explicitly mention ruʿya (sighting of the new moon) as a method to determine the beginning of a new Islamic month. However, most of these narrations appear to have been given in the context of refuting the following two pre-existing positions with regards to moon sighting:
- The month of Ramadan (or for that matter, any new month) always completes a cycle of 30 days.
- The new Islamic month can be determined through predications and assumptions.
These narrations indicate that ‘sighting’ (as opposed to completing 30 days or predicting in advance) is a more accurate and reliable ‘means’ (ṭarīq) of establishing the start of a new month.3 Furthermore, narrations do not provide details of sighting, such as whether the new moon should be sighted in an individual’s place of residency or anywhere in the world; or whether the sighting should occur with the use of the naked eye; or if technological aids or astronomical calculations are sufficient.
A thorough analysis of the hadith literature therefore leads to the conclusion that a ‘sighting’ of the new moon was the most reliable and accurate means available at the time to determine the beginning of a new Islamic month. Accordingly, it can be concluded that the primary criteria set forth in the hadith literature is of reliability and accuracy. During the presence of the Prophet and Imams, the most convincing method of determining the natural occurrence – or what the Quran describes as a beneficial cosmic event – of the birth of the new moon, was ruʿya (sighting).
3. Present day astronomers can scientifically calculate the different phases of the moon. They have access to resources that allow them to accurately pinpoint the different phases of the moon. Thus, modern astronomers can tell us in advance the time and dates of lunar conjunction, and when it will come out of the conjunction. Based on the understanding that sighting (ruʿya) of the new moon has no value apart from it being an accurate means of establishing that the new moon is out of conjunction, it can be proposed that in the present day the most accurate way of establishing that the new moon is out of conjunction is to rely on astronomical calculations. If in the future a more reliable method of establishing the new moon is found, then that should be given preference over the current method
of astronomical calculations.
4. Since the emergence of the new moon is a natural cosmic event that can be astronomically calculated, it must be applicable to all regions that share the night. Here ‘night’ occurs from sunset to dawn (i.e. till the time for fajr prayers). If the moon comes out of conjunction at any moment during the night, that day marks the first of the Islamic lunar calendar. On the other hand, if the moon comes out of conjunction during the daytime, the following day will be marked as the first day of Islamic calendar.
References:
[2] Holy Quran 2:185
[3] For a detailed study of the narrations, see Shaykh Tūsī, Tahdhīb al-aḥkām, 4:154-180