8.13 The ‘moon sighting’ controversy

8.13 The ‘moon sighting’ controversy14

In the Islamic calendar, traditionally, the first sighting of the new crescent moon by the unaided human eye marks the beginning of the month. In particular, such sightings are considered essential with regard to the start of Ramadan and the two Eid festivals. However, the unreliability of the dependence on physical visibility of the moon has led not only to wide variations in the three important dates within the same country, but also to a great disunity among the Muslim communities throughout the world. The problem can be easily solved if the traditional method is abandoned in favour of a purely scientific method. Before outlining the scientific method, I will examine what the Qur’an has to say on this matter. One can then decide whether the scientific approach is at odds with what is stated in the Qur’an.

Relevant Qur’anic guidance:

(6:96) It is He who cleaveth the daybreak (from the dark). He made the night for rest and tranquillity, and the sun and the moon for the reckoning (of time) […]

(10:5) It is He who has made the sun the source of light and the moon a reflected light and measured out the stages for her that you may know the number of years and the count (of time). This is nothing but a part of His constructive design […]

(55:5) The sun and the moon follow courses (exactly) computed.

(9:36) Lo! The number of months with Allah is twelve months by Allah’s ordinance in the day that He created the heavens and the earth […]

(2:189) 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 […]

Before discussing the implications of these verses I would like to outline the problems with the visual method, and the ways that a scientific method might overcome them.

Problems with the visual method:

For the moon to be visible to the naked eye the former must set after the sun has set. Some people use this condition to define the start of the lunar month, no matter how small the time interval between the two settings. Unfortunately, this method rests on one’s position on the earth and is therefore prone to divergence on the degree of accuracy. It also opens the debate on how sunset and moonset should be defined and whether allowance should be made for atmospheric refraction (as is done, for example, in a formalised but not in actual way in the Astronomical Almanac). If the actual refraction is less or greater than that assumed in the formal computation of the Nautical Almanac Office, sunset may not occur precisely at the tabulated time.

There is another very important factor which has to be taken into account for the lunar crescent to be visible; i.e. the age of the moon from the instant the conjunction (defined below) starts. ‘This age-criteria has been studied by various people by taking random observations and is usually stated in the form of general rules such as the sightings of the moon younger than 20 hours are rare and the sightings of the moon older than 24 hours are not uncommon, although its visibility may at times require it to be more than 30 hours old’.15

Thus the problem of the visual sighting of the crescent moon is caused by several factors depending on the interval between the conjunction and the next sunset; the actual position of the crescent moon with respect to the horizon; the clarity of the atmosphere and the visual acuity of the observer. For example, if the conjunction takes place in the very early hours of the morning it might be possible to sight the crescent moon on the same day, but if it is nearer the time of the sunset then the sighting, most likely, will be on the following day. There is no way of judging the point of demarcation which would indicate whether the crescent moon will be visible on the day of the conjunction or on the following day. The visual method, in this day and age, is totally incongruous and needs to be replaced by something which does not violate the principles outlined by the Qur’an. Let us examine this further:

The scientific or the astronomical method:

The scientific method is based on the physical conditions when the earth, the moon, and the sun, are in the same vertical plane but not necessarily in the same line, and the moon is between the earth and the sun. This condition is known as the ‘conjunction‘. In scientific or astronomical terms, the ‘conjunction’ is defined as the condition when the sun and the moon has the same ‘right ascension’.16In effect, this condition is the mark of the start of the lunar month. What is more the moment of its occurrence can be calculated precisely, being independent of any terrestrial locations. In fact, it is so accurate that it is possible to use the conjunction to calculate the lunar calendar for hundreds of years ahead.

The implications of the scientific method:

First of all, one must accept the fact that the required condition of identifying a lunar month will be met, so long as the scientific method guarantees the presence of the crescent moon, irrespective of whether the crescent moon is visible to the naked eye or not. At conjunction, the moon is not completely shadowed as viewed from the earth. However, the degree of illumination is so low that for us it is completely invisible. The apparent eastward motion of the moon then produces changes, in the shape of an illuminated disk, as a result of the changing geometry of the moon with respect to the sun and the earth. These are called the ‘phases of the moon’ and the Islamic New Moon is the instant of the start of the crescent phase. Thus, just after conjunction, although the crescent moon is not visible to the naked eye, there is no doubt that it is present in the sky. Hence, scientifically speaking, we can regard the crescent moon as physically present and the only thing we need to know is the exact time when it appears.

Fortunately, though the time interval between the conjunction and the crescent phase of the moon is very small it can be calculated accurately. The maximum time taken by the moon to move away from the sun is 19 minutes and therefore, 19 minutes after the moment of conjunction, the moon begins to reflect light towards the earth. In other words, scientifically, the crescent phase of the moon starts 19 minutes after the moment of conjunction, although the light may not become visible until 20 to 30 hours after conjunction. In the UK, the conjunction times for a number of years can be obtained from the Royal Astronomical Observatory. If we assume that the day changes at 12 p.m., then the conjunction can take place any time between 00.00 a.m. to 12 p.m. on any particular day. This means that the crescent moon can then appear any time between 00.19 a.m. of that day to 00.19 a.m. of the following day. Thus, 19 minutes after the moment of conjunction the Islamic New Moon appears. Therefore, Ramadan or any other important event can take place on the following day i.e. the day after conjunction. Such a method would allow for the easy publication of the dates well in advance so that people would not be unduly inconvenienced. After all, Allah desires for us ease, not hardship (2:185). Outside the UK one need only convert the same conjunction time to the appropriate local times, by adding or subtracting the time difference applicable, as is done for any other international activities. Although the conjunction is independent of any terrestrial location, the international time variations will still apply, simply because of the time gaps that exist between countries.

Finally, if — as some people suggest — it is not acceptable to use 12 p.m. for the change of a day, then one need only establish an agreed reference time other than 12 p.m., so long as it be internationally for all other activities. However, the principle remains the same, i.e. to use the conjunction as the start of a lunar month. The Qur’anic guidance advocates the use of both the sun and the moon for the reckoning of time. The use of the exact instant of conjunction is doing just that, as the conjunction starts at the instant when the sun and the moon have the same right ascension. The second condition that the new moon is to mark fixed periods of time is also met as the crescent phase starts 19 minutes after the conjunction.

The Qur’an, nowhere says that the moon has to be observed with the naked eye, rather it tends toward the scientific or the astronomical method. There are numerous verses in the Qur’an encouraging us to think, to ponder, to explore and to gain knowledge, and the moon-sighting should not be the exception.

(45:13) And He has made subservient to you, from Himself, all that is in the heavens and on earth: in this behold, there are messages indeed for people who think!

(3:190) Lo! In the creation of the heavens and the earth and (in) the difference of night and day are signs for men of understanding.

(10:5) […]Allah created not this but with truth. He makes the signs manifest for people who have knowledge.


  1. The True Translation of the Glorious Qur’an, by Late Ali Ahmad Khan Jullundri. Published by World Islamic Mission, 18-K Gulberg 2, Lahore, Pakistan. Refer to notes on verse 5:38.
  2. Ibid., verse 5:38.
  3. (i) Arabic English Lexicon, (8 parts), by Edward William Lane. Published by Islamic book centre, 25-B, Masson Road, P.O. Box 1625. Lahore-3, Pakistan.
  4. (ii) Arabic-English Dictionary: The Hans Wehr Dictionary of Modern Written Arabic. Edited by J. M. Cowan. Published by Spoken Language Services, Inc. P.O. Box 783. Ithaca, New York.
  5. Does the Qur’an Sanction the Hitting of Women? by Rachael Tibbet. p.1.
  6. Letter to Al-Balaagh, Nov/Dec 1996 issue. P.O. Box 1925, Lensia1820, South Africa by Dr. Sayed Abdul Wadud. (Lahore, Pakistan).
  7. Letter to Al-Balaagh, Nov/Dec 1996 issue. P.O. Box 1925, Lensia 1820, South Africa by Basheer Ahmed Vania. (Lensia, South Africa).
  8. Most of the Qur’anic verses are taken from: The Message of the Qur’an, by Muhammad Asad. Published by Dar Al-Andalus, Gibralter.
  9. Women in Islam, by B. Aisha Lemu and Fatima Heeren. Published by The Islamic foundation, 223 London Road, Leicester LE2 1ZE. p.28.
  10. Ibid., p. 28, 29.
  11. Is Hijab Compulsory? Article by Professor Dr. Ibrahim B. Syed Phd. D.Sc. Published in Al-Balaagh, Vol. 22, No.1, Feb/March 1997. P.O. Box 1925, Lensia, South Africa.
  12. Jihad, Haji Ibrahim Golightly: A question – answer printed in the Message, the UIA magazine of July – September issue, 1995.
  13. The Religion of Islam, by Maulana Muhammad Ali M.A., LL.B. Published by National Publication and Printing House U.A.R. Based on chapter 5, pp. 545-595.
  14. A pamphlet entitled The Islamic View on the Prohibition of Alcohol, by S.M. Bleher. Published by UK Islamic Mission Dawah Centre, 401-403 Alum Rock Road. Birmingham B8 3DT.
  15. The Islamic Tradition of “Moon Sighting” and its Implications, by M. A. Malek.
  16. A Modern Guide to Astronomical Calculations of Islamic Calendar, Times & Qibla, by Dr. Mohammed Ilyas. Berita Publishing Sdn, Bhd. Kuala Lumpur, Malaysia.
  17. Ibid. p. 10.