Book of Fixed Stars

The Book of Fixed Stars (in Arabic: كتاب الكواكب الثابتة) is an astronomical text composed by Abd al-Rahman al-Sufi (Azophi) around 964. The book was written 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 were 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 the earliest known 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. The first recorded mention of the Large Magellanic Cloud was also given by Abd Al-Rahman Al Sufi in his Book of Fixed Stars.

He probably also cataloged the Omicron Velorum star cluster as a "nebulous star", and an additional "nebulous object" in Vulpecula, a cluster now variously known as Al Sufi's Cluster, the "Coathanger asterism", 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 visible from Southern Arabia, although not from more northern latitudes.

Notes

References

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

External links

• Biography of Al Sufi
• A page about Muslim Astronomers