Astronomer and mathematician. (B. 1526, Damascus – D. 1585, Istanbul). He was the son of Maruf Efendi who was a teacher at madrasahs in Damascus. He took Arabic and Koran lessons during his primary education. From then on, he began to show interest to astronomy and mathematics. In 1550 he went to Istanbul together with his family. There, he took lessons from the famous scholars of the era; Çivizâde, Ebussuud, Kutbuddin, Saçtı Emir. Having completed his education, he taught at madrasahs in Damascus and Cairo. He was appointed to Istanbul Edirnekapı Madrasah as a lecturer during the era of Grand Vizier Semiz Ali Pasha. Upon Ali Pasha’s assignation to Egypt, he returned to Cairo; he taught at madrasahs and became a kadi (T.N. Islamic judge). After a while, he began to concentrate upon astronomy and mathematics with the promotion of Kutbuddin, his teacher. He benefited from the written works of Ali Kuşçu, Giyaseddin Cemşid Kişi and Kadızâde Rumi. He had observed the sky and he placed his equipment in an observation well he had sunk while he was the kadi of Tinnin. During the era of Sultan Selim II, he went back to Istanbul and was appointed to Müneccimbaşı (the chief court astrologer).
Ever since he was a boy, Takiyüddin had been always interested in astronomy and had done studies on astronomy. He caught attentions of Hoca Saadeddin, the tutor of Sultan Murat III, and Sokullu Mehmed Pasha with his observations in Galata Tower in 1574. After that, in 1579, it was decided that an observatory was going to be built and it was built on Tophane upon the firman of Murad III. His books about astronomy and equipment were brought to that observatory. He built a library himself there and did studies to complete and renovate Zij-i Sultani of Ulugh Beg. The public backlash against the observatory got even worse when the plague epidemic erupted soon after a comet was seen and Murad III ordered demolition of the observatory upon fatwa of Shaykh al-Islam Kadızâde Ahmed Şemseddin Efendi telling: “Observatories bring destruction wherever it is located.” and all equipment were broke into pieces (1580). Takiyüddin went aside after the destruction of his observatory which was considered as the best observatory of the east and the west in historical records and which was the only observatory in the Ottoman Empire and he passed away after a little later.
It is seen in miniatures in manuscripts, “Şehname” and “Şemailname”, in the Istanbul University Library that there were astrolabe, quadrant, mechanical clock, hourglass, celestial spheres, spherical Earths and some drawing tools in the observatory. According to books of Takiyüddin, there were also some immovable tools such as equatorial ring, mural quadrant, parallax tool which was used for calculating how far away a star was and sextant which was used for measuring the positions of stars.
Takiyüddin Raşid who was one of the significant scholars of the Ottoman Empire wrote various books about mathematics, astronomy, physics, optics, mechanics and medicine. As is understood from his books, he was mostly interested in astronomy and he did studies in other fields in order to benefit from them in astronomy. That his finding of irregularities in motions of moon, planet world and other planets was so similar to today’s findings shows how sophisticated he was in astronomy.
Takiyüddin did important studies in mathematics along with astronomy. He demonstrated proofs of some trigonometric terms, provided descriptions of those terms, designed table of tangent and sinus. He established his own number systems in the field of arithmetic and began to use decimal fraction instead of sexagesimal. Besides, he re-evaluated arguments and problems in optical studies done for eight centuries in Islamic world in a casual and mathematical context and reinforced them with new experiments he had conducted.
Sidretü Müntehe'l-efkâr fî melekûti'l-feleki'd-devvâr, Reyhânetü'r-rûh fî resmi'ssâcat calâ müsteve's-sütûh, Cerîdetü'd-dürer ve hande tü'l-fiker, Dekâ'iku ihtilâf i'l-ufkayn, es- Simârü'l-yânica min kutûfi'l-âleti'l-câ- mica, ed-Düstûrü'r-ra- cîh li-kavâ'idi't-tastîh, Âlât-ı Raşadiyye li-Zîci 'ş-şehinşâhiyye, el-Mizveletü'ş-şimâliyye bi-fazli dâ'iri ufuki Kostantîniyye, Fevâ'id fi'stihrâci mıntıkati'l-kürre- ti ve macrifeti'l-ceyb, Risâle fî macrifeti'l-ufki'l-hadîş, Risâle fî evkâti'l-cibâdât, el-Kevâkibü'd-dürriyye fî vaz'i'l-benkâmâ ti'd-devriyye, et-Turuku's-seniyye fi'lâlâti'r-rûhâniyye, Nevru hadîkati'l-ebşâr ve nuru hakîkati'l-enzâr, Buğyetü't-tullâb min cilmi'l-hisâb, Kitâbü'rı-Nise- bi'l-müteşâkile fi'l-cebr ve'l-mukâbele, Risâle ti cameli'l-mîzâni't-tabfî el-lezî yu'lemu bihî mâ fi'l-cismi'l-mürekkeb min ma'deneyn muhtelifeyn, Tercümânü'l-etıbbâ ve lisânü'l-elibbâ, Şerhu'l-ebyâti't-tisc fi'stih- râci't-tevârîtıi'l-meşhûre, el-Meşâ- bihu'l-muzhire fî cilmi'l-bezdere.
REFERENCE: A. Süheyl Ünver / İstanbul Rasathanesi (1969), Sevim Tekeli / İstanbul Rasathanesinin Araçları (1979), Büyük Larousse (c. 18, s. 11172-11173, 1986), Ana Britannica (c. 20, s. 348, 1987), Ekmeleddin İhsanoğlu vd. / Osmanlı Astronomi Literatürü Tarihi (1997) - Osmanlı Matematik Literatürü Tarihi (1999) - Osmanlı Tabii ve Tatbiki Bilimler Literatürü (2006), Remzi Demir / Takiyüddin'de Matematik ve Astronomi (2000), Göğe Bakan Adam: 420. Ölüm Yıldönümünde Takiyüddin Raşid Sempozyumu (C. Şenel, A. Bir, H. G.Topdemir, İ. Fazlıoğlu, M. Kaçar, R. Şeşen, R. Demir; 19 Kasım 2005), Hüseyin Gazi Topdemir / TDV İslam Ansiklopedisi (C. 39, s. 454-456, 2010), İhsan Işık / Ünlü Bilim Adamları (Türkiye Ünlüleri Ansiklopedisi, C. 2, 2013) - Encyclopedia of Turkey’s Famous People (2013).