Astronomical calculations versus naked eye sighting of the crescent to determine lunar months in Islam

By Simwal Usman Jibril

I believe in naked eye sighting of the crescent in accordance to the sunnah of our beloved Prophet (S.A.W.) .

The Prophet (S.A.W.) said : 

صوموا لرؤيته و افطروا لرؤيته 

Fast at its sighting, and break (end) the fast at its sighting. (Muslim) 

الا تصوموا حتى تروا الهلال و لا تفطروا حتى تروه 

Do not fast until you sight the crescent and do not break (end) the fast until you sight it. (Buhari). Some Islamic organizations internationally like Turkey, Fiqh council of North America (FCNA), Islamic society of North America (ISNA) etc and some few organizations locally (though to the best of my knowledge no local organization has openly deliberated and adopted astronomical calculations openly) but some of them depend on astronomical calculations to announce beginning and ending of Ramadan, days before the actual sighting day which is the 29th day of a lunar month.

Astronomy or astronomical calculations can eliminate errors , false illogical sighting claims and guide us in gaining experience in sighting the crescent and follow the Prophet‘s (cm) order and enjoy the fun of astronomy as promoted by Shariah.

The scholars of Fiqh unanimously agree that the Sharia approved cause for confirming the beginning of fasting is sighting the crescent and that using astronomical calculations in this regard is rejected, regardless of whether the sky is clear or cloudy. Some few decades ago a group of scholars contradicted this consensus and presented reasons to adopt astronomical calculations as an approved way of beginning and ending Islamic lunar months. I will mention the reasons given by these scholars to adopt astronomical calculations and i will try to explain the inaccuracies in the following reasons.

1– They claim that since sighting of the crescent is not an act of worship. It is simply a means to know the entry of the month of Ramadan .Since astronomical calculation can accurately determine the birth of the new moon, they believe using the birth of the moon is enough and sufficient to determine the beginning of Ramadan.

Sighting of the crescent is an act of worship and therefore not rationalizable, Ramadan may only begin with the sighting of the crescent. The vast majority of scholars, many of whom were very competent in astronomical computation, held that the sighting of the crescent is an act of worship.

They did so on the basis that the sighting of the crescent moon is a declaratory law, that is assigned by Allah to determine the beginning of Ramadan (سبحانه وتعالى) 

Sighting of the crescent as a cause for fasting is not a ruling which may change depending on the existence or non existence of an effective cause. We do not investigate nor modify the cause itself, which is a declaratory law. Had Allah (S.W.T.) wanted, He could have ordered the beginning of Ramadan to be immediately after the crescent of Shabaan disappears or even assigned a time period after Sha‘baan ended. He, be exalted, did neither. He assigned the beginning of Ramadan specifically to the sighting of the crescent. And since the entry of Ramadan is the reason for the beginning of fasting, sighting the crescent is the sabab (cause) for the entry of Ramadan. Both are declaratory laws assigned by Allah (S.W.T.).

2–They also claim that seeing the moon does not really mean actual physical sighting and may mean considering, pondering, ascertaining or having assurance.

The following two Hadith are the relevant arguments for this claim 

وموا لرؤيته، وأفطروا لرؤيته 

”Fast at its sighting, and break (end) the fast at its sighting 

“ لاتصوموا حتى تروا الهلال ولا تفطروا حتى تروه 

Do not fast until you sight the crescent and do not break (end) the fast until you sight it. (Buhari).

The following observations are important. Linguistically, the word “hilal” means a crescent, which is something visible. Hilal traditionally refers to a crescent that is at least one or two nights old and does not therefore refer to the birth of the moon or conjunction , which cannot be seen with the naked eye.

Secondly, the word seeing (ru’yah ) in the Hadith must be interpreted in its literal sense in accordance with the basic rule, a word must be taken in its literal meaning and not metaphorical meaning unless it is impossible to understand it literally and there is a circumstantial reason for assigning it a metaphorical meaning. It is not impossible to understand ru’yah to mean seeing. The physical sighting of the moon was always the practical understanding of the word ru‘yah.

Moreover, the physical sighting of the moon is a communal obligation (Fardul kifayah) and not a personal obligation (Fardul ayn ).

3– They claim the command to physically sight the crescent was due to the fact that Muslims at that time did not know how to write or calculate. The Muslim community today does have knowledge in these areas and they believe actual sighting is no longer necessary based on the following Hadith: 

“We are an unlettered nation, we do not write or calculate. The month is such–and–such or such–and–such – meaning sometimes it is twenty–nine and sometimes it is thirty.” (Narrated by Buhari 1814; Muslim, 1080). 

The main reason of this argument is that the command to physically sight the moon was due to the reason “We are an unlettered nation. We do not write nor count (or compute). The month is like this and like this....” Since the reason does not exist any longer in modern times that is, we now know how to write, count and compute, they claim we no longer need to rely on physical sighting.

The Prophet (S.A.W.) for example, did not say, “We are an illiterate nation, because of that, or therefore, fast when you see the moon…” The logical question should be, is literacy of any importance to the duration of a month, will it affect whether the month is 29 or 30 days. This is, however, impossible since the lunar month is always 29 or 30 days and is illustrative of the fact that illiteracy is not intended to be an effective and main cause of determining a month. The Prophet (S.A.W.), instead, is informing us that in this particular matter of fasting they do not compute or calculate.

4– They also claim that sighting the crescent is only a means to establish the month. Modern science can calculate the birth of the moon and the beginning of the month with accuracy.

As mentioned in the second argument, “Do not fast until you sight the crescent...” the Prophet (en used the strongest, most unequivocal language that sighting and only sighting is the first means of ascertaining the beginning of the month. The text is explicit and definitive in its meaning, the manner of deduction is directly from the text “hilal”, as mentioned earlier as well, is the visible crescent. And seeing (ru‘yah) must be understood in its literal understanding unless it is impossible to do so. There can be no doubt whatsoever that the Prophet (S.A.W.) intended the physical sighting of the crescent.

5– Another claim is that Muslims all over the world, especially in the West, suffer a great deal of hardship due to physical sighting. Additionally, they also claim that physical sighting is a cause of disunity and discord.

The hardships enlisted include waiting late in anticipation of sighting reports, scheduling and costing issues for Eid are issues also mentioned as difficulties for Muslims in western countries. Another reason is, those leaving in western countries need to apply for a leave from work on the day of Eid, they claim with astronomical calculations it‘s easy to know Eid day days before the day.

It must be understood that Islamic law does not aim to ameliorate every hardship but only excessive hardship that is regular and not rare. The claim that costing and scheduling issues for venues for Eid prayers in western countries is difficult. Even a cautious two–day reservation for a hall for Eid prayers in western countries hardly qualifies as excessive hardship. Taking two days leave from work shouldn‘t be a difficult task too, because we all know the month is either 29 or 30 days. 

It‘s significant to acknowledge that astronomical calculations compliments naked eye sighting and goes a long way in preventing errors, it‘s noteworthy to mention some of the ways that astronomical calculations is helpful to naked eye sighting of the crescent. 

1– it is used to know time of conjunction ( new moon) so any sighting claim before conjunction is outrightly rejected.

2– Sun rise and Sun set of any location can be accurately calculated and same applies to Moon rise and set can be accurately calculated too, any sighting claim after moon set can also be rejected.

3– The crescent azimuth, altitude are accurately calculated. The azimuth is the location of an object in the sky in a circle of 0–360°, 0° is true north. Altitude tells us how far above the circle of the horizon to look for an object, from zero to 90 degrees. An object sitting right on the horizon would have an altitude of 0°. Knowing the above mentioned coordinates makes it easier to locate a crescent. 

4– In astronomy moon‘s elongation is the angular separation between the Sun and the moon, with Earth as the reference point. Conjunction occurs when the moon‘s elongation is 0 ° , first quarter phase Occurs when elongation is about 90° and full moon occurs when the moon‘s elongation is about 180 ° . Naked eye sighting possibility of a crescent starts when the moon‘s elongation is about 7 degrees.

In conclusion for over 1400 years Scholars have maintained the natural, sacred and communal way of determining beginning of Islamic lunar months , which is sighting the crescent with naked eye which is the sunnah of our beloved Prophet (S.A.W.). Allah knows best. May Allah bless our most beloved Prophet (S.A.W.) with the purest of blessings. And may He guide us all, through His most beloved, to what is most beloved to Him ameen.

*Simwal Usman Jibril Twitter: @simwal Member: Islamic crescent observation project Abu Dhabi UAE www.icoproject.org National moon sighting committee of Nigerian supreme council for Islamic affairs Abuja, Nigeria. Islamic research and timing organization Kaduna, Nigeria. Astro qiblah initiative Kaduna, Nigeria.