Abu Ishaq Al Zaraqali: A Scholar Who Lived for Knowledge

Abu Ishaq Al Zaraqali was a renowned astronomer and inventor in Islamic Spain, a flourishing center of Islamic culture and learning. He was born in AD 1029 (420 AH) in Toledo, Spain. His full name was Abu Ishaq Ibrahim Ibn Yahya Al-Naqqash Al-Zaraqali. The title "Zaraqali" means "blue-eyed." He became famous in the Western world as Arzachel.

He mastered astronomy, engineering, and mechanical design. His innovations influenced both Islamic and European scientists, including Johannes Kepler and Regiomontanus.

Al-Zaraqali came from a family of artisans skilled in mechanical devices. He completed his education in Qurtuba (Córdoba) and then moved to Toledo, where he joined the scientific circle of Sultan Al-Ma'mun. His primary task was constructing instruments for astronomers working on major astronomical projects. His exposure to these endeavors inspired him to contribute groundbreaking inventions.

One of his most notable contributions was the Toledan Tables, a collection of astronomical data that significantly improved the calculation of planetary positions. These tables were developed through collaboration with Judeo-Muslim astronomers. Al-Zaraqali also invented a water clock and a sophisticated astrolabe named Safiha, used to calculate star positions and heights. His explanations of these devices were translated into Hebrew and Latin.

He accurately calculated the speed of the solar apogee as 12.0 seconds per year, remarkably close to today’s measurement of 11.8 seconds. He also corrected Ptolemy’s estimation of the Mediterranean Sea’s length, which Ptolemy had recorded as 62°, while Al Zaraqali accurately measured it as 42°.

Al Zaraqali’s insights predated Copernicus; he proposed that the planets move in elliptical orbits and stated that the sun, not Earth, is the center of the solar system.

His scientific rigor earned him leadership in several research projects. His Water Clock gained widespread recognition and was even praised by the Jewish poet Moses bin Ezra. However, due to political upheaval caused by Alfonso VI’s invasion, Al Zaraqali left Toledo in 1078 and returned to Cordoba, where he continued his work until he died in AD 1100.

His major work, Toledan Tables, covered topics such as proper ascensions, solar and lunar equations, eclipses, parallax, and trigonometric tables. These works were translated by Gerard of Cremona into Latin around AD 1187 and widely circulated in Europe and the Islamic world.

Al-Zaraqali's two public water clocks in Toledo remained in use until 1133, when King Alfonso VII ordered their dismantling, as no one could understand their mechanisms.

In summary, Abu Ishaq Al Zaraqali was an outstanding Muslim scientist whose contributions laid the groundwork for much of modern astronomy and scientific thought.