a Muslim polymath active in the Ottoman Empire. He was the author of more than ninety books on a wide variety of subjects, including astronomy, clocks, engineering, mathematics, mechanics, optics and natural philosophy. In 1574 the Ottoman Sultan Murad III invited Taqi ad-Din to build the Istanbul observatory. Using his exceptional knowledge in the mechanical arts, Taqi ad-Din constructed instruments like huge armillary and mechanical clocks that he used in his observations of the Great Comet of 1577. He also used European celestial and terrestrial globes that were delivered to Istanbul in gift-exchange.
