Is the sighting of the Ramadan crescent moon in Libya to be relied upon if it is the only country that announced its sighting, and is the legal (Shar'i) sighting or astronomical calculation to be relied upon?

Scholars differ on the issue of establishing the sighting of the crescent moon: Is it a general sighting for all Muslims, or does each country have its own sighting?

The preponderant opinion is that each country has its own sighting, based on the narration of Ibn Abbas with Kuraib and Ibn Abbas’s interpretation of it.

As for what establishes Ramadan (definition), it is the sighting of the crescent moon, even if by one reliable person, or the completion of thirty days of Sha’ban.

Scholars differed regarding the case of cloudy weather on the 30th night of Sha’ban: 1. Imam Ahmad and a small group held that the meaning of "فَاقْدُرُوا لَهُ" (then determine it) is to reduce the number, meaning making Sha’ban twenty-nine days and fasting the next day if clouds prevent the sighting of the crescent. 2. The majority held that the month is established by sighting or by completing the count to thirty days, and that the meaning of "فَاقْدُرُوا لَهُ" is to complete the count to thirty days, and fasting on a cloudy day does not suffice for Ramadan. 3. Some said that its meaning is to determine it by astronomical calculations of lunar mansions.

The preponderant view is that the month is established by sighting the crescent, and if it is obscured, then Sha’ban should be completed to thirty days. This is the opinion of the majority, because the opinion of determining it under clouds contradicts the clear meaning of other narrations, and the opinion of astronomical calculation is refuted by the Prophet’s (peace be upon him) hadith (definition): "Indeed, we are an unlettered nation; we neither write nor calculate." The Islamic Fiqh Council has decided to rely on sighting for establishing the new moons, not astronomical calculations.