Hüseyin Sen holds a BSc in aeronautical technology and is a historian of science. Currenlty he is a PhD candidate at the department of the History of Mathematics, Mathematical Institute of Utrecht University, specializing in the history of Arabic/Islamic science. He is writing an intellectual biography of Taqi al-Din ibn Ma'ruf (d. 1585), the court astronomer of Ottoman sultan Murad III. Taqi al-Din is one of the most important Ottoman scientists and wrote works on many fields, such as astronomy, mathematics, optics, physics, zoology and pharmacology. For this research project, Sen analyses the astronomical observations made by Taqi al-Din.