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(by Eng. Qamar Uddin, ICOUK; dated 10 October 2026) [download pdf] | [Image - Square] | [Image - Portrait]
Understanding the 1 - 2 Day Difference in Moon Sighting
The Islamic month begins with the sighting of the crescent moon (in your country of residence) - not simply because another country has announced a new month.
LOCAL MOON SIGHTING MATTERS
Since 2018, the ICOUK has developed a consistent local moon-sighting system, with Islamic months lasting 29 or 30 days. Depending on the moon's visibility from different locations, the UK may begin a month one day, and occasionally two days, different from Saudi Arabia.
IS A TWO-DAY DIFFERENCE WRONG?
No. A difference of two days does not, by itself, make a local moon-sighting decision contrary to Shariah.
Countries that base their Islamic months on actual crescent visibility may differ from Saudi Arabia's Umm al-Qura calendar. Such differences can arise from geographical location, crescent visibility, and the criteria used to determine the beginning of a month.
India, with over 172 million Muslims (14%) and a long-established tradition of local moon sightings, is another example of a country whose Islamic dates can differ from Saudi Arabia. [1448-04: Hijri Date India | Deoband Hilal | Saudi Umm al-Qura]
WHAT SHOULD GUIDE UK MUSLIMS?
- ✓ Follow reliable moon-sighting evidence and sound Islamic scholarly guidance.
- ✓ Recognise legitimate differences arising from local visibility and accepted sighting criteria.
- ✓ Do not assume that Saudi Arabia's dates must automatically apply to the UK.
- ✓ Judge the validity of a sighting decision by its evidence and Shariah principles, not merely by the number of days' difference.
ONE UMMAH, DIFFERENT HORIZONS 
A difference in dates is not, by itself, proof of a mistake.
Support authentic local moon sightings in the UK.
Related: (1) UK Moon Sighting Fatawa | (2) Hijri Date India on X | (3) Ummul Qura Calendar
Checked by: ICOUK Ulama Panel (10/2026)
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Predictions for Eid ul Fitr 1445-1455
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(by Eng. Qamar Uddin, ICOUK; dated 31 March 2026) [download pdf] | [How do lenses work?] | [FOV Calculator]
1. Introduction
We have received clear guidance (fatwa) on the use of Optical Aids for UK moon sightings, provided they are not “extraordinary”, which could show the moon when it’s invisible to the human eye[1] (e.g., CCD/CMOS imaging). Therefore, we have reviewed the recent moon sighting data from our past reports and concluded that the astronomy binoculars and telescopes listed below are suitable for UK moon sightings. They are given for guidance purposes only.
2. Optical Aids
2.1 The astronomy binoculars below have 15 to 25x magnifications with varying light-gathering capabilities that make the moon bigger and brighter, and hence easier to see with the naked eye at the eyepiece (mounted on a suitable tripod).
 Celestron Skymaster 15x70 |
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2.2 The refractor telescopes (with AZ-GTI mount) below have good-quality optics and can track the moon automatically, if it has been aligned correctly. A 400 - 500 mm FL telescope with a 10 - 25 mm eyepiece will give 20 - 50x magnification.
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Sky-Watcher |
Sky-Watcher |
Sky-Watcher |
3. Rationale
Many existing fatawa allow the use of Optical Aids for moon sightings without any restrictions, but some UK scholars seem to believe that modern Optical Aids are too powerful and could show the moon beyond the visible light range. Therefore, a clear policy on the use of Optical Aids is required, which is suitable for moon sightings but not as powerful as the Hubble or JWST Telescopes (with 500x to 600x magnification), which can show distant galaxies or nebulae! They use REFLECTION (large mirrors)[2], whereas most moon sighting optical aids are relatively low-powered, like binoculars and small telescopes (with 20x to 50x magnification), which use REFRACTION (glass lenses). Furthermore, from our recent ICOUK moon sighting reports, we have found that the minimum threshold for sighting the moon with Optical Aids is 3° altitude (in winter) and 9° elongation approx. (in spring), which are well within the naked eye visibility range.
The reason for stating the minimum lunar parameters and the type of Optical Aids commonly used is to justify them for UK Moon sightings to assist/support the naked eye, as they are not powerful enough to show the invisible moon!
DISCLAIMER: This policy document may be revised in the future without further notice.
[1] “Use of Optical Aids and Cameras for UK Moon Sightings”, Fatwa by Darul Uloom Karachi (2/2025) / [bit.ly/icoukOpticalAids]
[2] Note that Reflection (mirrors) is mainly used for digital sensors, and Refraction (lenses) is mainly used for eyepieces (optical aids).
Related: (1) Use of Optical Aids for UK Moon Sightings / (2) UK Moon Sighting Fatawa
Checked by: Hameed Mamaniat/Mufti Abdul Waheed (3/2026)
4. Fatawa from All 4 Sunni Madhabs
4.1 Malaysian Fatwa (2021)
We have received the Malaysian scholars (JAKIM) fatwa on the use of Optical Aids for moon sighting, approved by all their (Shafi) Fiqh scholars, which may be downloaded from the ICOUK website link below. [bit.ly/MalaysianFatwa2021] Note: When we asked them about their basis for changing from naked eye to Optical Aids, they informed us that there was a difference of opinion between REFLECTION (using mirrors) and REFRACTION (using lenses). Since the Optical Aids use REFRACTION technology, they are considered permissible. You can find the Fiqh references for the above rulings in the PDF document.
4.2 Libyan Fatwa (2010)
We have received a Libyan fatwa on the use of Optical Aids for moon sighting (according to the Maliki Madhab), which may be downloaded from the ICOUK website at the link below. [bit.ly/LibyanFatwa2010] Note: When we asked the HialFrance scholars what their Fiqh ruling was for allowing Optical Aids. They told us they follow the Maliki Madhab, which allows the use of Optical Aids. You can find the Fiqh references for the above rulings in the PDF document.
4.3 Ibn Bazz Fatwa (1990)
Is using a telescope to confirm the crescent moon of Ramadan an innovation (bid'ah)? We have received a Saudi fatwa on the use of Optical Aids for moon sighting (according to the Hanbali Madhab), which may be downloaded from the ICOUK website link below. [IbnBazzFatwa1990x] Note: The fatwa makes it clear that using Optical Aids is permissible, just like using cars, airplanes, telephones, etc., in our lives, and they are not bid'ah (or against the Sunnah) in Islamic law!
4.4 South African Fatwa (2016)
Optical Aid to Sight the New Moon: We have received a South African fatwa on the use of Optical Aids for moon sighting (according to Hanafi Madhab), which may be downloaded from the ICOUK website link below. [bit.ly/HanafiFatwa2016] Note: All the 4 Sunni Madhabs allow Optical Aids for moon sightings in general. The difference between old and new fatawa is based on REFLECTION and REFRACTION. You can find the Fiqh references for the above rulings in the PDF document.
If you have any comments regarding the above article, please email us via our on-line Contact Us form.