This year’s Ramadan could end in 28 days as Saudi’s supreme court has asked Muslims across the country to look for the new moon today evening. Sighting the moon later today would mean Muslims could celebrate Eid Ul Fitr on Wednesday which would correct an earlier moon-sighting error.

According to newspapers in Saudi, a statement issued by the court read, “Those who witness the moon should inform the nearest court. If the moon was not sighted on Tuesday, they should look for it on Wednesday evening.”

Previously, Eid-Ul-Fitr was expected to fall on either Thursday or Friday. It is believed an error in the lunar citing to mark the onset of Ramadan has caused the confusion. The odd event has happened only once in 30 years. The last time Ramadan ended in 28 days was in 1984.

Muslims across the world follow the lunar calendar which marks the onset of a new month based on the sighting of the new moon.