Astronomer hispano-Arabic, Azarquiel (Abu Ishäq Ibrahim Ibn Yahyà Al-Zarqalluh) worked in Cordoue and Tolède. He built astronomical instruments.

He invented a sophisticated astrolabe (the azafea): a double projection planes which makes it possible to represent the movement of stars on the sky. The principle of its construction is known since the Greque time; but its current use was widespread only by the astronomers of Islam, starting from the VII ^E century. Of use limited for the astronomical observations, it is useful especially for astrology, the teaching of astronomy, and the calculation of the hour during the night. It was the principal instrument of navigation since the XVI ^E century to the XVIII ^E century, at the moment when the sextant was invented.

Azarquiel also wrote to them “Tablas Toledanas” (Tables tolédanes) and other important works of astronomy as the “Book of seven planets”.

He lived in Tolède until the conquest of Alphonse VI of Castille. He was an important actor of the Moslem culture in the Iberian peninsula.