Al-Sufi (903-986)

 
Painting of Astronomer/Astrologer, possibly al-Sufi, from 10th century Persia.
 
Picture from the "Book of Fixed Stars", showing M31 just in front of the mouth of the fish.

Abd al-Rahman Al Sufi, known in the West as Azophi, was one of the most outstanding practical astronomers of the Middle Ages. He lived at the court of the Emire Adud ad-Daula in Isfahan (Persia), working on astronomical studies based on Greek work, especially the Almagest of Ptolemy. In 964 Al Sufi published his famous book "Kitab al-Kawatib al-Thabit al-Musawwar" ("Book of Fixed Stars"), a masterpiece on stellar astronomy. It is considered important even now for the study of proper motions and long period variables.

In his descriptions and pictures of Andromeda, he included "A Little Cloud" which is apparently the Andromeda Galaxy M31. He mentions it as lying before the mouth of a Big Fish, an Arabic constellation. This cloud (marked "A" on the picture) was apparently commonly known to the Isfahan astronomers, very probably before 905 AD.

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