The Ottoman Empire was founded in 699AH\1299AD, after the death of Ertugrul, that started with his successor Othman, who established the Empire, which lasted more than 600 years until it ended in1341AH\1922. So, during those centuries, Ottomans had contributed to many fields of knowledge, science and astronomy. They were in a great deal of creativity, innovation and scientific production. They paid attention to what other predecessors of the other nations had studied. Also, wrote many unique works that became essential references for all the world. They did not stop there; but built observatories and invented machines. As well as developing the astronomical observatories in their time for noticing the planets, stars and drawing their positions.This study examines the interest of astronomy in the Ottoman period, and the role played by astronomical observatories in that period as a kind of Muslims heritage, also the famous astronomical observatories during that period, especially Helwan Observatory.Furthermore, the present study investigates the importance of Helwan Observatory in discovering many natural phenomena. The current study discussed the location of Helwan Observatory, the architectural design of the historical building, and its museum, as many rare and historical pieces joined to the Tourism and Antiques Ministry.The study applies historical, descriptive and analytical approaches, as it focuses on the history of the observatories during the Ottoman period. As well as the great role of Helwan Observatory in discovering important natural phenomena and the description of the architecture design of the historical building.
Elmallwany et al. (2025) studied this question.