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Astronomy
Nasir al-Din al-Tusi
Director of Maragha Observatory — 1201–1274 CE
Built at Maragha the largest scientific observatory before modern times (a library and precise instrument models) and led a multinational team. He invented the Tusi couple, the mathematical device correcting lunar motion by combining two circular movements — the same mechanism Copernicus is presumed to have inherited through intermediary sources two centuries later.