Ramadan is expected to start on July 20 and Eid Al Fitr may begin on August 18, the state news agency Wam has reported.
Ibrahim Al Jarwan, astronomer and supervisor at Sharjah Planetarium, said the new moon will occur on July 19 at 8.24am but will not be visible until the evening of the next day.
That would make Saturday, July 21, the first full day of Ramadan.
The new moon must be seen for Ramadan and Eid Al Fitr to begin.
Ramadan is the ninth month of the Islamic calendar, during which Muslims fast from sunrise to sunset. They refrain from eating, drinking, chewing gum, smoking and other forms of temptation.
Non-Muslim residents are asked to show respect by following the same rules in public during daylight hours.
Eid Al Fitr marks the start of the Islamic month of Shawwal and the end of Ramadan.
The Dubai Astronomy Group has planned a moon-sighting trip to mark the occasion.
"I highly encourage people to use astronomy and physically go and observe it," said Hasan Al Hariri, the head of the group. "But I highly discourage people to predict the moon themselves without any background or knowledge.
"We do talks in Ramadan and we try to make people more familiar with real astronomy. Islam says that astronomy is very, very good and we should learn from it."
Mr Al Hariri will pack his telescope and head to the desert with his children and friends.
The Ramadan moon sighting is a tradition he has followed since childhood, when he would go on to Dubai rooftops with his family.
"We used to make it a celebration," he said. "I try to maintain it year after year so my children also love astronomy."
Ramadan can occur on different days in different countries, even within the Gulf.
"The visibility of the moon should be a way to unify us, not to divide us," Mr Al Hariri said.
"If we in the Arabian Peninsula have seen the moon somewhere it's very good for us to take all of it together."
azacharias@thenational.ae
