Abū l-Ḥusayn ʿAbd al-Raḥmān b. ʿUmar al-Ṣūfī (291–376/902–86), a famed astronomer known in Europe as Azophi, is renowned for his expertise on the fixed stars and the constellations. Born in Rayy, he appears to have spent his life in Iran, where he had a close relationship with the rulers of the Būyid dynasty and particularly with his patron, ʿAḍud al-Dawla (r. 338–72/949–83), in Shīrāz. In 335/946–7 he visited Dīnawar and in 337/948–9 Isfahan, both in the company of Ibn al-ʿAmīd (d. 360/970), the learned wazīr of ʿAḍud al-Dawla’s father, Rukn al-Dawla (d. 366/976).

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