According to many Fuqaha (Legal Scholars), such as Sayed Sistani, Makarim Shirazi and Sayed Sadiq Shirazi, – the beginning of the lunar month must be confirmed by the appearance of crescent on the horizon in a way that is visible to be seen by the normal naked eyes if not concealed by the clouds and other external things, therefore the astronomers’ announcement about the birth of the crescent cannot be considered for the entry of the new lunar month even if it is based on the conclusive mathematical calculations. The following is a summary of why astronomers announcements are neglected.

Their announcement about the possibility of sighting the crescent by the normal naked eyes in certain areas or in all places in very clear weather, depends on two elements:

First, it depends on the special astronomical calculations about the state the crescent in those areas, i.e. its age, height on the horizon and its angle distance from the sun and other sort of factors that effect the sighting.

Second it depends on the applied authentic astronomical experiments for observing the crescent for being sure that the least required conditions are available for sighting it by the normal naked eyes, i.e. its age, height and its distance from the sun and so on.
These are controversial among the astronomers. For example, some of them state the possibility of sighting the crescent at the age of 14 hours, others state its age must be at least 16 hours, and others put it at 18 hours and so on. Some of them state the possibility of sighting it at the height of 4 degrees on the horizon, while others state that 5 degrees is required and others put it at 6 degrees. It is the same for other effecting conditions in sighting.

Therefore, there is no way for the Mukalaf to take the astronomers’ announcement into account about the possibility of sighting the crescent in this or that place without being sure that the appearance of the crescent is in a way it can be seen by the normal naked eyes and not contradicting with the texts that forbid relying on the opinion and presumption:

أبي جعفر عليه السلام قال : إذا رأيتم الهلال فصوموا وإذا رأيتموه فافطروا وليس بالرأي ولا بالتظني ولكن بالرؤية
Imam al-Baqir said, “If you sight the crescent fast, and if you spot it again breakfasting and do not fast by opinion or assumption but by sighting.”

Source: Tahthib al-Ahkam, Volume 4, Chapter 41, Hadith #5 (See Image below)


Some may argue that this method of sighting the moon is outdated because we did not have the “tools” that we do now – and science has helped develop our technology to help us.

However, there is no denying that the actual new moon can and does benefit with use of technology – but an important factor must be considered: The astronomical month is different to the legal month.

The legal month, being the month the Muslims accept for religious obligations, strictly begins when and only when it is sighted by the naked eye (according to many fuqaha). The senses are used to determine a religious verdict – rather than the reality.

Some examples of this would be:

1. the subject matter of blood that legal texts have identified as impure (Najis) does not mean the real blood even if it cannot be seen by eyes but blood that can be felt by the sense, as in the case of change of purity to impurity of the water which drops of blood or urine have fallen in. The change to impurity does not occur unless the water that is kept in a big container (kurr) has changed, and what is meant by the change is the change in colour, taste or smell that can be here felt by the senses and not the actual change that cannot be felt by the sense.

The same applies to the matter of the month referred to in the legal texts, as Allah has revealed in this Qur’anic verse, “So every one of you who is present (at his home) during that month should spend it in fasting.” The reference here is to the month known to the Arabs that lies between two crescents and not the astronomical month which starts at the moment the moon begins coming out from the waning position but cannot been seen from earth, but the crescent that can be seen by the naked eyes and Allah confirm this in this Qur’anic verse, “They ask thee concerning the New Moons. Say: They are but signs to mark fixed periods of time in (the affairs of) men, and for Pilgrimage.” So the crescent becomes a sign for identifying a ‘fixed period’ when it is visible enough to be seen. So, if the traditional month is the one that is identified by the common practice starts from the moment the crescent being visible enough to be seen by the naked eyes, the coming out of the moon from the waning position cannot be considered as the start of the month.

2. the issue to be judged sometimes has a natural existence and legal one as in the ‘son’ case because, for example, a son can be identified naturally and by the common practice as the one who is born from a semen of a man but the ‘legal son’ is the one who is born as a result of a marriage contract between a man and a mature female. Likewise, the start of the legal month is not the same as the astronomical one.

We must also remember that astronomical data have been known since that time (of the Imams), though scientific progress in recent time makes things more precise. It may be claimed that the Imams have not used the knowledge to uncover ‘the unseen’, though they have the ability to do so, they have followed the apparent standards because the possibility of sighting the crescent in a country sharing the night with the imam’s does not require the knowledge of finding out the unseen but could be realised by having experience about the countries and their conditions as the possibility of sighting the crescent depends on three things:

1. The degree of the rise of the crescent from the horizon.
2. The angle distance of the crescent to the sun.
3. The size of the luminous of the crescent to the largest circumference of it.

All which were available at the time of the Imams (as) but were not considered by them as viable. Despite the accuracy increasing in time – many fuqaha say it still is irrelevant based upon the ahhadeeth of ahlulbayt (as).

It is the authentic narrative of Mohammad Bin Issa who has reported that Abu Amru wrote to the Imam asking him. “My Master could you please tell me when we are in doubt of the visibility of the crescent of the month of Ramadan and we cannot sight it even though the sky is clear and people breakfasting and we follow them in this regard and some of the mathematicians stated before us that the crescent was seen on that same night in Egypt and Africa and Andalusia. Is, my Master, the claim of the mathematicians acceptable in this regard and the obligation on people of Amsar (the conquered countries by Muslims) is different so the time of their fasting and fast-breaking will be different from our times?” The Imam stated by saying, “Do not fast when you are not sure, fast on sighting the crescent and break-fasting when you see it at the end of the month.”

Source: Tahthib al-Ahkam, Volume 4, Chapter 41, Hadith #18 (See Image below)


It is also important to note that the scholars do not reject the use of astronomers for calculations either. Science is a very powerful tool. An example is Sayed Sistani (hf) who rejected the many testimonies in many countries in the year 1419H, that they sighted the moon based upon the consensual astronomers testimony that it was impossible to sight – and that those who sighted might have been victims of their senses (eye-sight) that led them to think what they have seen was the crescent. This was used amongst other proofs for Sistani (hf) going against many testimonies that the crescent was sighted.

Some of the living/recent Maraja’ that follow this method of strict moon sighting:

1. Sayed Sistani
2. Makarim Shirazi
3. Sayed Sadiq Shirazi
4. Sh. al-Ihqaaqi
5. Sh. al-Khaaqani
6. Sh. Zain al-Deen

Others who do not accept astronomers testimonies, but do accept other methods of validity such as sharing the same night (N) or viewing in Telescope (T):

1. Sayed al-Khoei (N)
2. Sh. al-Fayyadh (N)
3. Sayed al-Hakeem (N)
4. Sayed al-Rohani (N)
5. Sh. al-Ha’eri (N, T)
6. Sh. Mahmood al-Hashimi (N, T)
7. Sayed al-Khamene’i (T)

Note: Please refer to their risalah for specifics, this is just a general guide.

A final note is that most maraja` [such as Sayed Sistani (hf), Waheed Khorasani (hf) and Nasir Makarim Shirazi (hf)] have also stated the testimonies of Astronomers can be considered only when one has gained (through knowledge AND experience) absolute certainty in their testimonies. They leave this up to the mukallif (the follower of the marja`).

Sayed Sistani (hf) states:

Yes, if knowledge and satisfaction are gained even through experiment and practice that the crescent is present on the local horizon in such a size and height, and in spite of the effecting factors in sighting, it is visible enough to be seen by the normal naked eyes or cannot be seen because of the clouds, fog or dust or something similar to them, the Mukalaf is allowed to employ his knowledge and experience for his satisfaction.

Source: Moonsighting Questions & Answers, Page 45 (See Image Below)


He also states:

1741. The first day of a month will not be proved by the prediction made by the astronomers. However, if a person derives full satisfaction and certitude from their findings, he should act accordingly.


Nasir Makarim Shirazi (hf) states:

Issue No. 1457- The 1st of a month will not be proved by calendars or the calculations made by the astronomers, though they may be knowledgeable and accurate, unless one derives full satisfaction and certitude from their findings. Similarly, if the moon is high up in the sky, or sets late, it is not an indication that the previous night was the first night of the month


A key point is that one should note the astronomers prediction must be for the sighting of the moon, and not the birth of the new moon. If the astronomers prediction is that is is possible to sight the moon had there been no barriers (such as clouds) then you can take their word if you have gained full conviction. This is not the same as taking their prediction for the birth of the new moon, which at times cannot be sighted in the city you are in.

The difference in opinion about the evidence of the lunar month is inescapable because the jurists (fuqaha) have different evidence about the start of the lunar month, and each person has to adopt the opinion of the scholar (Marj’ he follows in executing his religious duties) as in other religious matters which jurists have different opinions about. True believers must accept the difference in opinion and this issue must not be a source of disputes and dissatisfaction among Muslims, and if the social necessity or any other reason forces an individual to breakfasting in that day, the person who is still fasting because of the opinion of Marj’ can travel the legal required distance that allows him to break-fasting to celebrate Eid with his community and compensate for that day later, though our Ulma try their utmost efforts to make Muslims celebrate Eid in one day if the legal evidence allow them to do so in order to relieve themselves in front of Allah, the Glorified, the Exalted.

We hope success for the true believers and Allah may accept their fasting and make the day of Eid a blessed happy one.