Zij al-Sabi is an ancient astronomical text written by the Persian scholar Al-Battani in the 9th century. It is known for its detailed observations of celestial bodies and its contributions to the development of trigonometry. The work was influential in both the Islamic world and later in Europe, where it helped shape the understanding of astronomy. The title "Zij al-Sabi" translates to "The Tables of the Sabians," referring to the Sabians, a group known for their interest in astronomy and astrology. The text includes tables for calculating the positions of the sun, moon, and planets, making it a valuable resource for astronomers of its time.