İSLÂM TARİHİNDE RASATHANELER.

The aim of this article is to determine the observations established in Islamic history chronologically and to introduce these institutions in terms of their basic features. As it is known, there was no observatory in the periods before Islam. Astronomical observations were usually done with transportable instruments. When the Muslims saw that the Ptolemy astronomy system they initially accepted had made some mistakes, they decided that it was necessary to observe for a long time to correct them and set up an observatory to realize this. Although there is some information that the first observatory in Islamic history was established in Damascus during the Umayyad period, researchers generally accepted that the first observatory was the Semmâseiye Observatory established in Baghdad by Me’mûn. A year later, Me'mun had built a second observatory in Damascus on Mount Kasiyun to make observations. After that, establishing observatories became the tradition of Islamic states, and close to fifty observatories were established in the Islamic world until the end of the Ottomans. [ABSTRACT FROM AUTHOR]