Ramadan in 2019 will begin on May 6 in most Islamic nations, according to the International Astronomical Centre.
The new crescent moon will be impossible to spot with the eye in most Arab nations, across East and South East Asia, and in southern Europe on Sunday, May 5.
Because it will only be possible to see the moon with a telescope that day, the first day of the holy month will fall on Monday, May 6, according to Mohamed Shawkat, the director of the centre.
Eye sighting of the moon will also be difficult in western and southern African countries and most of the United States on May 5, although it should be relatively easy in Central America.
The prediction is in line with many other astronomers, who have predicted Ramadan will begin on May 6.
The job of officially calling the start – as well as the end of Ramadan – will be down to the Moon Sighting Committee.
Why is a moon sighting committee used to announce the start of the holy month?
The Islamic calendar is determined by moon phases, which are either 29 or 30 days long. So the presence of a new moon signals the start of a new month in the Islamic calendar.
The committee will begin searching for the new crescent moon after Maghrib prayers on the 29th day of Sha’ban, the Islamic month preceding Ramadan. If it cannot be seen, or is known using calculations to not be in the sky, it is considered to be the 30th day of the month.
But if the new crescent is spotted, Ramadan begins the following day. The process is repeated again to mark the end of the holy month and the first day of Shawwal, the 10th month. However, searching for the new crescent can be a little tricky, because it is usually faint and is only seen for about 20 minutes.
Read more on the moon sighting here
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