Abu al-Hasan ‘Ali ibn ‘Abd al-Rahman ibn Ahmad ibn Yunus al-Sadafi al-Misri;
(Arabic: ابن يونس; c. 950 – 1009) was an important Egyptian Muslim astronomer and mathematician, whose works are noted for being ahead of their time, having been based on meticulous calculations and attention to detail.
Information regarding his early life and education is uncertain. He was born in Egypt between 950 and 952 and came from a respected family in Fustat. His father was a historian, biographer, and scholar of hadith, who wrote two volumes about the history of Egypt—one about the Egyptians and one based on traveller commentary on Egypt. A prolific writer, Ibn Yunus’ father has been described as “Egypt’s most celebrated early historian and first known compiler of a biographical dictionary devoted exclusively to Egyptians”. His great-grandfather had been an associate of the noted legal scholar Imam Shafi.