Our question is:
Should we follow the European Fatwa Council even though they use calculations to determine the beginning and end of Ramadaan, or should we continue our efforts to unite the mosques in Our city even though that goes against the view of the Council?.
It is not permissible to use astronomical calculations to establish the beginning and end of Ramadaan. It is obligatory to sight the moon as the Prophet (peace and blessings of Allaah be upon him) said: “Fast when you see it (the moon) and break your fast when you see it.”
Narrated by al-Bukhaari, 1909; Muslim, 1081. See also question no. 1602.
The Muslims are agreed that it is not permissible to follow astronomical calculations instead of sighting the new moon if the sky is clear. However if the sky is cloudy then some of the scholars held an odd view and said that it is permissible to follow astronomical calculations, but this applies only to the person doing the calculations.
Shaykh al-Islam Ibn Taymiyah (may Allaah have mercy on him) said:
It is a basic fact of Islam that we must sight the crescent moon with regard to fasting, Hajj, ‘iddah, eelaa’ (period of four months abstention which is required if a man swears an oath that he will not have marital relations with his wife) and other rulings that are connected to the lunar calendar. There are many texts from the Prophet which indicate that, and the Muslims are unanimously agreed on that. No difference of opinion was known concerning that in the past or in modern times, apart from some fuqaha’ after the third century AH, who claimed that if the new moon is covered by clouds it is permissible for an astronomer to follow calculations himself, so that if his calculations indicate that the moon could have been sighted he may fast, otherwise he should not.
This view, even though it is subject to the condition that there be clouds and it applies only to the astronomer, it is an odd view that is outweighed by the consensus on the opposite view. With regard to following calculations when the sky is clear or applying the results of the calculations to the general public, this is something that no Muslim has ever suggested.
Majmoo’ al-Fataawa, 25/132.
Based on this, it is not permissible to follow the Council mentioned if they depend on astronomical calculations and not on sighting of the crescent.
So you have to sight the moon as is the command of the Prophet (peace and blessings of Allaah be upon him) and as is the consensus of the Muslims.
May Allaah help you to do that which He loves and which pleases Him.
And Allaah knows best.