Al-Zarqali

Abū Isḥāq Ibrāhīm ibn Yaḥyā al-Naqqāsh al-Zarqālī al-Tujibi (Arabic: إبراهيم بن يحيى الزرقالي); also known as Al-Zarkali or Ibn Zarqala (1029–1100), was an Arab maker of astronomical instruments and an astrologer from the western part of the Islamic world.

Although his name is conventionally given as al-Zarqālī, it is probable that the correct form was al-Zarqālluh. In Latin he was referred to as Arzachel or Arsechieles, a modified form of Arzachel, meaning 'the engraver'. He lived in Toledo, Al-Andalus before moving to Córdoba later in his life. His works inspired a generation of Islamic astronomers in Al-Andalus, and later, after being translated, were very influential in Europe. His invention of the Saphaea (a perfected astrolabe) proved very popular and was widely used by navigators until the 16th century.

The crater Arzachel on the Moon is named after him.

Al-Zarqālī, of Arab origin, was born in a village near the outskirts of Toledo, the then capital of the newly established Taifa of Toledo. He started work after 1048 under Said al-Andalusi for the Emir Al-Mamun of Toledo and also under Al-Mu'tamid of the Taifa of Seville. Assuming a leading position under Said, Al-Zarqālī conducted solar observations for 25 years from 1050.

He was trained as a metalsmith and due to his skills he was nicknamed Al-Nekkach "the engraver of metals". His Latinized name, 'Arzachel' is formed from the Arabic al-Zarqali al-Naqqash, meaning 'the engraver'.

He was particularly talented in geometry and astronomy. He is known to have taught and visited Córdoba on various occasions, and his extensive experience and knowledge eventually made him the foremost astronomer of his time. Al-Zarqālī was also an inventor, and his works helped to put Toledo on the intellectual center of Al-Andalus. He is also referred to in the works of Chaucer, as 'Arsechieles'.

In the year 1085, Toledo was taken by the Christian king of Castile Alfonso VI. Al-Zarqālī and his colleagues, such as Al-Waqqashi (1017–1095) had to flee. It is unknown whether the aged Al-Zarqālī fled to Cordoba or died in a Moorish refugee camp.

His works influenced Ibn Bajjah (Avempace), Ibn Tufail (Abubacer), Ibn Rushd (Averroës), Ibn al-Kammad, Ibn al-Haim al-Ishbili and Nur ad-Din al-Betrugi (Alpetragius).