, abu ‘l-Ḥusayn , eminent astronomer, born at Rayy ¶ 14 Muḥarram 291/8 Dec. 903, died 13 Muḥarram 376/25 May 986. In 337/948-9 he was in Iṣfahān, in attendance on the vizier Abu ’l-Faḍl b. al-ʿAmīd, in 349/960-1 at the court of ʿAḍud al-Dawla, no doubt in the same town. He was the court astronomer of this ruler, who boasted of three of his teachers: in grammar al-Fārisī, in the knowledge of astronomical tables Ibn al-Aʿlam, and in the knowledge of the constellations ʿAbd al-Raḥmān al-Ṣūfī (Ibn al-Ḳiftī; cf. also Yāḳūt, Irs̲h̲ād , iii, 10). His best known work is a description of the fixed stars ( Ṣuw…

, Ḵh̲ārid̲j̲ite leader (belonging to the Ibāḍi al-Nukkār [ q.v.]), who by his revolt shook the Fāṭimid realm in North Africa to its foundations. His father, a Zanāta Berber merchant from Taḳyūs (or Tūzar) in the district of Ḳastīliya, bought in Tadmakat a slave girl called Sabīka, who bore him Abū Yazīd about 270/883 (apparently in the Sūdān). Abū Yazīd studied the Ibāḍī mad̲h̲hab and became a schoolmaster in Tāhart. At the time of the victory of Abū ʿAbd Allāh al-S̲h̲īʿī he moved to Taḳyūs and started, in 316/928, his anti-government …