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Islamic Hijri Calendar Basics






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Islamic Hijri Calendar Basics

The basic facts in any discussion of Islamic Calendar / moon-sighting debate are: 

1.  “Ahilla” (waxing lunar crescent moons):

They are the Mawaqeet (indicators) for religious observances and for Hajj (2:189) 

2. Naked-eye observation:

The Messenger (SAW) continued the Arab (as well as the Jewish) Shari’ah tradition of clearly visible, mass-sighted local Hilal to begin the Islamic date and months. (Suumu li- ru’yatihi…) There were no eyeglasses or optical aids for observing the crescent moon. Binoculars, and telescopes were invented centuries later. 

3. Local date:

Each location had to go by its earliest sighting. The means of communications was non-existent. (Fa-huwa li-lailatin ra’itumu-hu, Kuraib, Ikrama, etc. Ahadith)  

4. Jewish lunar calendar

The modern-day (New Moon-based) Jewish lunar calendar was in use by the Jews in Medina. It was available for the Muslims during the time of the Prophet (SAW). The Prophet’s practice of fixing the first date of the Islamic lunar month by a crescent moon, sighted by the naked eye (instead of adopting the fixed calculated dates based on the conjunction) generated tension between the Muslim and the local Jewish communities in Medina. (Nahnu Ummatun Ummiyah Hadith) 

The Prophet (SAW) asked the Muslims to abide by the naked-eye-sighted Ahillah rule to begin / end their Islamic month and for fixing Islamic religious observances, and not go by the Jewish calendar for Islamic dates.  

5. The Purpose of lunar observation:

The sole purpose of the observation is to begin / end the Islamic lunar month. (La Tasuumu  ... wa la Tuftiru …Fa in ghumma alikum fa-kmilul-Iddata thalatheen). 

The Muslim jurists added details such as 1, 2 or more witnesses, Ikhtilaaf : Ittihad al-Matali; etc. With the advent of rapid means of communication and expansion of geophysical knowledge, complications arose by the middle of 20th century. Conflicting Fiqh positions evolved to solve local and regional Islamic calendars. It was all before a comprehensive understanding of the complications of a round earth for lunar calendars.

Earliest visibility

Fixing the Islamic date by the earliest lunar visibility means: 1) The Islamic month must start on 2,3, or more solar dates, because the lunar visibility takes 3+ days to cover most of the globe (with perfect clear skies everywhere); and 2) Each lunar month is 29 and 30 days long at the same time because the earliest visibility each month moves westwards and starts from a different location. The region that lies between the eastern-most tips of the visibility curves of two successive months has 30 days while the rest only 29.

Optical aid Visibility

Naked-eye sighting, binocular and telescopic sighting, visual-light imaging and non-visual-light imaging have serious implications for fixing the first date of a lunar month. To realize a “real difference between a naked eye observation and that by an optical aid" and the CCD imaging please look at Odeh’s 3 July 2008 lunar visibility curves. A (easily naked-eye) begins from east of Cuba and extends north / westwards to almost Vancouver (Canada) in the north; B (Visible in perfect conditions) starts from western Africa and extends to cover most of Canada); C (Need optical aid) begins from Chad (Central Africa); D extends farther eastwards, covering Sudan and Egypt, etc.; and E (optical aid) covers most of S. Arabia, southern Europe, etc. (Keep in mind that the rest of the globe would see a Hilal only on July 4 and 5, 2008.) 

The distance from the eastern-most tip of D (55E for Visual aid) to A (60W for Naked eye curves) on July 3, 2008 by Odeh’s own calculations was almost ten thousand miles, covering a time span of 10+ hours from Somalia to Cuba. The first date in this region could start anywhere depending on one’s preferred “earliest visibility” criterion. 

Observation through eyeglasses DON’T change the first Islamic date. Other optical aids (binoculars, and telescopes) result in starting / ending the Islamic month a day early. Many observers have reported that they could see a first day lunar crescent through binoculars only, and not by naked eye, though they tracked it till the moonset.

CCD Imaging

CCD imaging has introduced an irrelevant dimension to the debate. It is a processed image that is enhanced beyond the visibility limits of un-aided eye and optical-instruments. If the processed image of the morning is invisible to the naked eye or an optical aid by the moonset then it is of no value for fixing an Islamic month.

Islamic date / month

An Islamic month has to be 29 or 30 days long, and not 29 1/2, 30 1/2 or any fraction (which is now very easy to calculate to the millionth of a second). The primary goal is to use "modern techniques /equipment) for the purpose of "accurate religious observance.” Many in the moon-sighting debate have totally ignored the primary purpose of “lunar observation” and have created baffling calendrical complications by their proposed solutions of Hijri dates (for local, regional, zonal, continental, or global). Any deviation from the original definition must be strongly supported by Shara’i and logical arguments.

Can we look at the issues dispassionately and help evolve a workable Islamic Hijri calendar, instead of confusing the Ummah further by new definitions of Hilal, visibility and fractional length of days for lunar months?   May Allah help us. Ameen.