Synchronising Widget Dates with Actual Moon Sighting

The Islamic lunar months are 29 or 30 days long. Traditionally, actual moon sighting activities take place after the sunset of 29th lunar date. If verified sighting reports are received then the new month starts from the next day, otherwise, the month is completed as 30 days.

The predicted dates (Imkan Al Ruyat) used in the ICOUK Hijri Calendar Widgets are highly accurate, but on rare occasion, the Widget dates may not match with actual moon sighting decisions. This may happen in borderline cases due to undetermined factors (e.g. Zones of Uncertainty).

Hijri Cal Auto Refresh Check2Therefore, on every 29th lunar date, the Widgets will try to Auto-Refresh the calendar data from the ICOUK Hijri database via the Internet before 12 midnight of the UK local time. If the Widget is unable to contact the web service, it will display a warning message on the bottom of the calendar (“No network connection. Please reconnect and refresh data”) for the user to manually refresh the data (see screenshot on the right). It will also replace ICOUK (✓) with a red question mark (?). See the setting description (13) in the previous section how to manually refresh the calendar data.

It is important to note that the Auto-Refresh function is not valid for those using the Widgets from outside the UK. They must wait until 12-midnight of the UK local time (e.g. after 3 am in Saudi Arabia) before manually refreshing the calendar data and then adjusting the dates for the new month to the local calendar using Adjust Day and Month options (if necessary).

Reasons for changing the Hijri date at Midnight

According to Islamic tradition, the Hijri date is effective from sunset to sunset. However, since the geographical location of the UK is above 48° latitude, which causes sunset to be very late during the summer months (i.e. 9:30 pm - 10 pm), leaving the Hijri date to change at 12-midnight is more prudent as it enables sufficient lead-time to carry out actual moon sighting, verification and decision-making process before updating the results on the ICOUK website database (for remote devices).

Furthermore, the website services are less resource-hungry at midnight than at early evenings, which helps the shared servers provide a more efficient service to many thousands of devices accessing the online database. It is also less confusing for new users to have both the Gregorian and the Hijri dates change at the same time.

Reasons for the start day of the week from Sunday

The names of the week in Arabic are:  Sunday (الأحد), Monday (الإثنين), Tuesday (الثلاثاء), Wednesday (الأربعاء), Thursday (الخميس), Friday (الجمعة) & Saturday (السبت).

The first day of the week being a Sunday (Yawm Al-Ahad, the First day) is also from the Tafsir of the Quran (Tafsir Ibn Kathir, Quran 7:54).

Hence, the Islamic week starts on a Sunday (i.e. not Friday) and ends on a Saturday (the seventh day of the week, as mentioned in above Tafsir). Therefore, the ICOUK Hijri calendar uses Sunday for the start of the week (in both Arabic and English). Note that the day name on the calendar has been abbreviated for space limitation reasons (i.e. to work on small devices).


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