Taqi ad-Din Muhammad ibn Ma'ruf ash-Shami al-Asadi (Arabic: تقي الدين محمد بن معروف الشامي; Ottoman Turkish: تقي الدين محمد بن معروف الشامي السعدي; Turkish: Takiyüddin‎ 1526–1585) was an Ottoman polymath active in Cairo and Istanbul.

He was the author of more than ninety books on a wide variety of subjects, including astronomy, clocks, engineering, mathematics, mechanics, optics, and natural philosophy.

Taqi ad-Din constructed instruments such as an armillary sphere and mechanical clocks that he used to observe the Great Comet of 1577.

His major work from the use of his observatory is titled "The tree of ultimate knowledge [in the end of time or the world] in the Kingdom of the Revolving Spheres: The astronomical tables of the King of Kings [Murad III]" (Sidrat al-muntah al-afkar fi malkūt al-falak al-dawār– al-zij al-Shāhinshāhi).

The first 40 pages of the work dealt with calculations, followed by discussions of astronomical clocks, heavenly circles, and information on three eclipses which he observed in Cairo and Istanbul.

As a polymath, Taqi al-Din wrote numerous books on astronomy, mathematics, mechanics, and theology.

His method of finding coordinates of stars were reportedly so precise that he got better measurements than his contemporaries, Tycho Brahe and Nicolas Copernicus.

[4] Taqi ad-Din also wrote a book on optics, in which he determined the light emitted from objects, proved the Law of Reflection observationally, and worked on refraction.

[8][9][10] In his treatise, titled "Rayḥānat al-rūḥ", Taqī al-Dīn himself claimed descent from the Ayyubids[11][12] tracing his lineage back to the Ayyubid prince Nasir al-Din Mankarus ibn Nasih al-Din Khumartekin who ruled Abu Qubays in Syria during the 12th century.

[13] The Encyclopaedia of Islam makes no mention of his ethnicity, simply calling him, "...the most important astronomer of Ottoman Turkey".

Al-Dīn used a new method to calculate solar parameters and to determine the magnitude of the annual movement of the sun's apogee as 63 seconds.

[15] The main purpose behind the observatory was to cater to the needs of the astronomers and provide a library and workshop so they could design and produce instruments.

This was due to the manuscript collecting efforts of Jacob Golius, a Dutch professor of Arabic and mathematics at Leiden University.

He must have succeeded in acquiring it later since Taqī al-Dīn's work on optics would eventually make it to the Bodleian Library as Marsh 119.

[15] According to Salomon Schweigger, the chaplain of Habsburg ambassador Johann Joachim von Sinzendorf, Taqi al-Din was a charlatan who deceived Sultan Murad III and had him spent enormous resources.

[3] The founding of the Constantinople Observatory began when Taqī al-Dīn returned to Istanbul in 1570, after spending 20 years in Egypt developing his astronomy and mathematical knowledge.

[18] During the early years of his position as head astronomer, Taqī al-Dīn worked in both the Galata Tower and a building overlooking Tophane.

These newfound relationships lead to an imperial edict in 1569 from Sultan Murad III, which called for the construction of the Constantinople Observatory.

[19] It was closed in 1579 and, was demolished entirely by the state on 22 January 1580, only 11 short years after the imperial edict which called for its construction.

Due to his father's occupation as a professor at the Damascene College of law Taqī al-Dīn spent much of his life in Syria and Egypt.

Continuing his research on observations of the heavens while in Egypt Taqī al-Dīn used the Galata tower and Sokollu's private residence.

Although Murad III was the one who commanded an observatory to be built it was actually Sokollu who brought the idea to him knowing about his interest in science.

[20] Murad III made sure that there was proof of his accomplishments by having his court historiographer Seyyid Lokman keep very detailed records of the work going on at the observatory.

While working in this observatory, Taqī al-Dīn not only operated many previously created instruments and techniques, but he also developed numerous new ones.

European clockmakers began to create clocks designed to the tastes and needs of the Ottoman people.

The vertical pistons of the final machine are operated by cams and trip-hammers, run by the paddle wheel.