Just as the Ancient Greeks learned from earlier cultures, so did the Arabs and the Persians. They learned from the Greeks, in fact, and also the Hindus who lived further east.
They translated the work of Ptolemy, for example, into Arabic.
They built observatories such as at Samarkand and developed very detailed tables of the motions of objects in the sky. These made it possible for them to make precise predictions about future observations.
Find out about three Islamic astronomers,