One day Jibrā’īl (‘alayhis salām) was sitting with Rasūlullāh (sallallāhu ‘alayhi wa sallam). Meanwhile, Abu Dharr al-Ghifārī (raḍiyallāhu ‘anhu) appeared from far. Jibrā’īl (‘alayhis salām) said: “This coming person is Abū Dharr.” Rasūlullāh (sallallāhu ‘alayhi wa sallam) asked: “Do you know him?” Jibrā’īl (‘alayhis salām) said: “He is much more well known among angels than he is known among people.” Rasūlullāh (sallallāhu ‘alayhi wa sallam) asked: “How did he attain this degree?” Jibrā’īl (alayhis salām) replied: “This is because he struggles against his nafs (lower-self) constantly and recites Sūrah al-Ikhlās a lot.”

MUWAQQIT MUSTAFA BIN ALI

Muwaqqit *Mustafa bin Ali was born in Istanbul in the early 16th century. He became well known by the nickname “Koca Saatçi” (the great timekeeper) and specialised in Mathematics and Astronomy. He served as a muwaqqit in Yavuz Sultan Selim Mosque in Istanbul for many years. When calculating salāh times, he used -19 degree for imsāk and -17 degree for Ishā Salāh as the Sun’s lowering degree on the horizon. After his demise, Taqiyyud-din Rashid, the founder of the first observatory in the Ottoman State, took his post.

The books compiled by Muwaqqit Mustafa bin Ali on making and using astronomical tools are precious. He himself invented a tool named “Rub al-Āfāqī” that was used in observatories. He wrote numerous books on astronomy and calculating salah times some of which were used as reference books in madrassahs (Ottoman schools). Some of his amazing works are as follows:

I’lāmul-Ibād fī Akhbārul-Bilād: He wrote this book in Hijrī 931 (1525 CE) in which he divided the world’s populated areas into seven climates. In this book, night and day times of around one hundred countries from China to Morocco were explained and written in details, and the distances of those countries to Istanbul, the centre of Khilafah (caliphate), were given in miles. Muwaqqit Mustafa bin Ali presented this book to Sultan Sulaymān, the Magnificent.
Tukhfatu’z-Zamān wa Jarīdatu’l-Awān: This is a lengthy book written in Turkish which explains the science of calculating time and seven climates.