Kitab suwar al-kawakib al-thabita (Book of the Images of the Fixed Stars) of al-Sufi

This book, based on the Almagest of the Greek astronomer Ptolemy, concerns the forty‑eight constellations known as the Fixed Stars, which, according to the medieval conception of the universe, inhabited the eighth of the nine spheres surrounding the earth. The constellations each appear twice in mirror image, shown as observed from the earth and from the sky.