Abu Ja'far al-Khazin

Abu Ja'far Muhammad ibn Husayn Khazin, known as Al-Khazin, was a prominent Iranian Muslim astronomer and mathematician born in the year nine hundred in Khorasan. His contributions to the fields of astronomy and number theory have left a lasting impact on the scientific community.

During his career, Al-Khazin was summoned to the court of Ray, Iran, by the Buyid dynasty ruler, Adhad ad-Dowleh, who reigned from nine hundred forty-nine to nine hundred eighty-three. In the year nine hundred fifty-nine, he was tasked by the vizier of Ray to measure the obliquity of the ecliptic, showcasing his expertise and the trust placed in him by the ruling authorities.

One of his most notable works, Zij al-Safa'ih, also known as the