Zij as-Sindhind
Zīj as-Sindhind is a work of zij brought in the early 770s AD to the court of Caliph al-Mansur in Baghdad from Sindh in present day Pakistan. Al-Mansur requested an Arabic translation of this work from the Sanskrit. The 8th-century astronomer and translator Muḥammad ibn Ibrāhīm al-Fazārī is known to have contributed to this translation. In his book Ṭabaqāt al-ʼUmam "Categories of Nations", Said al-Andalusi informs that others who worked on it include ibn Sa'd and Muhammad ibn Musa al-Khwarizmi. He adds that its meaning is al-dahr al-dahir.
Content
This is the first of many Arabic zijs based on the Indian astronomical methods known as the Sindhind. The work contains tables for the movements of the sun, the moon and the five planets known at the time. It consists of approximately 37 chapters on calendar and astronomical calculations and 116 tables with calendar, astronomical and astrological data, as well as a table of sine values.As described by Said al-Andalusi, as-Sindhind divides time into cyclic periods of creation and destruction which are called kalpas.