"...The astronomical calculations and scientific facts should not be taken into consideration because they, and their like, have no evidence, neither from the Book, nor from the Sunnah, thus they cannot be deemed as part of AlBayyinaat, for there is no evidence to indicate that they are an evidence. To act upon such calculations is contradictory to what the Legislator (swt) has established as Sabab for fasting and contradictory to the rule that He (swt) has decreed in order to confirm the Sabab."

Therefore it is not permitted to follow the astronomical calculations in this act of worship and all acts of worship have their own set of rules that must be followed. These rules are found in the Quran and sunnah. It is clear that the sighting of the new moon is the Sabab (cause) to begin fasting, end fasting etc. It is as simple as that.

If the new moon is not sighted on the 29th night then we complete 30 days for the month. Simple.