'Abd Al-Rahman Al Sufi published his famous Book of Fixed Stars around 964, in Arabic, although the author himself was probably Persian. It was an attempt to create a synthesis of the most popular Classical work of astronomy – Ptolemy’s Almagest – with the indigenous Arabic tradition, or Anwa .

The book was thoroughly illustrated along with observations and descriptions of the stars, their positions, their magnitudes (brightness) and their color. His results set out constellation by constellation. For each constellation, he provided two drawings, one from the outside of a celestial globe, and the other from the inside

He has descriptions and pictures of what he called "A Little Cloud" which is actually the Andromeda Galaxy. He mentions it as lying before the mouth of a Big Fish, an Arabic constellation. This "cloud" was apparently commonly known to the Isfahan astronomers, very probably before 905 AD.

He probably also cataloged the Omicron Velorum star cluster as a "nebulous star", and an additional "nebulous object" in Vulpecula, a cluster now known as Al Sufi's or Brocchi's Cluster, or Collinder 399. Moreover, he mentions the Large Magellanic Cloud as Al Bakr, the White Ox, of the southern Arabs as it is invisible from Northern Arabia because of its southern latitude.

External links

• Biography of Al Sufi
• A page about Muslim Astronomers
• A catalog of medieval manuscripts from around the world.

Books on Muslim astronomy

• The Arabs and the Stars: Texts and Traditions on the Fixed Stars, and Their Influence in Medieval Europe (Variorum Reprint, Cs307) by Paul Kunitzsch