1. History of Astronomy in the Islamic World and the Istanbul Observatory Yavuz Ekşi

2. Observatory in Islam Observatory is a Islamic foundation. Islamic world needs accurate calenders to arrange the worshipping times. This was the basic motivation for building observatories. The produced catalogues of stars called “zic” mostly named after the King who financed the observatory. Yet there was also the more common foundations called “muvakkıthane”.

3. Basic World Model Islamic world believed in the Ptolemaic world model. Actually they translated Ptolemy’s book “matematica syntaxis” with the name “El Majestic” meaning “the greatest”. Then Europe translated it back with the name “Almagest”. Seven spheres of each planet was confirmed (as they thought) in Qouran which in many verses write about the “seven floors of the heavens”.

4. Tusi-Couple A mathematical device in which a small circle rotates inside a larger circle twice the radius of the smaller circle. Rotations of the circles cause a point on the circumference of the smaller circle to oscillate back and forth along a diameter of the larger circle. Tusi's diagram of the Tusi couple (Vatican Arabic ms 319, fol. 28v; 13th. c.)

5. Nasir al-Din TusiNasir al-Din Tusi (1201–1274)12011274 Resolved significant problems in the Ptolemaic system by developing the Tusi- couple as an alternative to the physically problematic equant introduced by Ptolemy.Tusi- coupleequant

6. Astronomy in Ottomans

7. Takiyuddin’s Observatory in Istanbul Takiyuddin (1526-1580) came to Istanbul in 1570 Convinced the Ottoman King (III.Murat) to build an Observatory. By observations Takiyuddin was to prepare a “zic” in the name of the King. With this renewed catalogue whorshipping times would be more accurately determined.

8. Istanbul Observatory (1577)

9. A comet at November 1577 This is the comet that Tycho Brahe observed.

10. Black Death in 1578 Gossip that all this evil arising because they have been observing the legs of the angels in the observatory Şeyhülislam (Ahmed Şemseddin Efendi): Observing the legs of the angels from the ground with pipes is a grand sin.

11. Black Death and the Şeyhülislam continues Şeyhülislam:İhrac-ı Rasad meş'um perde-i esrarı felekiyeye küstahane itlak-ı cür'etin vehamet ve akibeti meczumdur. Hiçbir mülkde mübaşeret olunmadı ki ma'mur iken harap ve bünyan-ı devleti zelzelenak-i inkilab olmaya. Observation brings illomens. The serious danger in attempting to understand the secrets of the celestial spheres should be obvious. In no country where observation is conducted there has ever been a case that the strong state had not been destroyed and the structure of the state was not shaken.

12. The End of the Observatory The king was scared and wanted the observatory to be broken down. This was done by Kılıç Ali Paşa in 1580 just after 3 years that the observatory started working. The second attempt to build a telescope in Ottoman Empire was in 1873 afer about 300 years. This also was broken down by the softas in 31 Mart event in 1909. Kandilli observatory was built in 1911 by Fatin Gökmen.

13. Even after 200 years since Copernic no one defending it in the Ottoman Empire!