The Difference Between Astronomical Calculation and Observation via Observatories

Question:
Shaykh, is there a difference between astronomical calculation and observation via observatories?

Answer:
There is a difference. Astronomical calculation is not permissible to rely upon for fasting, because it is a human effort that errs and hits the mark, and because the Prophet (peace and blessings be upon him) did not command us to fast based on astronomical calculation, but rather commanded us to fast based on the sighting of the crescent moon. This is the difference between them. Yes. And the sighting, whether it is by the naked eye or by means of a magnifier, magnifiers, telescopes at observatories, or otherwise, does not change the matter from being a sighting; rather, it becomes a sighting by means of an instrument. There is no harm in using magnifying instruments and observatories to sight the crescent moon, but this is not obligatory. Yes.