On Sunday evening, the UAE-based International Astronomical Centre (IAC) announced that its calculations showed it will not be possible to sight a new moon by the naked eye after sunset on Thursday 20 April from anywhere in the Arab World, adding that the crescent will only be sighted using a telescope from the western parts of Africa and Europe.

This would mean that Friday 21 April will be the last day of the month of Ramadan - and Saturday 22 April will be the first day of the month of Shawwal – i.e. the first day of Eid El-Fitr.

These calculations by the IAC differed from the ones reached by the the Egypt-based National Research Institute of Astronomy and Geophysics (NRIAG) 11 days ago, urging the NRIAG to issue its same statement again on Sunday.

On 6 April, the NRIAG had announced that its calculations show that a sighting of a new moon after sunset on Thursday 20 April was possible, and, therefore, Muslims can end fasting on Thursday and start celebrating the three-day Eid on Friday.

Already, millions of Egyptians have made plans to travel or to visit with families starting Friday based on the assumption that Thursday would be the last day of the fasting month.

The confusion was evident in a flurry of questions by users on various social media platforms: “When do we stop fasting?” and “Guys, when Eid starts?”

A top trending hashtag on Twitter in Arabic: "Eid_is_on_Saturday added fodder to the confusion.

Many Twitter users urged the IAC to issue a statement explaining its determinations.

In response, the IAC issued a new statement on Sunday night via Twitter to clear the air.

The centre claified that Eid El-Fitr will be observed on Friday in countries that rely on astronomical calculations.

However, the IAC added, Eid El-Fitr is expected to be observed on Saturday in a countries that depend on sighting of the new moon by the naked eye - if no crescent could be sighted on Thursday.

Wait for Dar Al-Ifta

Eid El-Fitr is the three day holiday celebrated by Muslims marking the end of the fasting of Ramadan.

It falls on the first day of the month of Shawwal – the 10th month of the Hijri calendar which is based on the lunar system.

A month in the Hijri calendar may either be 29 or 30 days according to sighting of new moons, which indicate one lunar month ends and a new one begins.

Some countries decide on Eid El-Fitr based on astronomical calculations.

Other countries – like Egypt - decide on Eid based on the sighting the moon with the naked eye or telescopes.

In Egypt, the decision on Eid - when Ramadan ends and Shawwal starts - is in the hands of the country’s Dar Al-Ifta.

As per tradition in Egypt, Dar El-Ifta will make this determination based on a confirmation of a sighting of a new moon after sunset on the 29 of Ramadan which falls on Thursday 20 April this year.

In any case, there is no need for anyone in Egypt to panic or change any Eid plans – WE still have 20 to 25 April a paid holiday for Eid and Sinai Liberation Day.