Dunash ibn Tamim
Dunash ibn Tamim was a Jewish tenth century scholar, and a pioneer of scientific study among Arabic-speaking Jews. He was a physician in ordinary at the court of the Fatimid caliphs of Kairouan, and to one of these, Isma'il ibn al-Ḳa'im al-Manṣur, Tamim dedicated an astronomical work, in the second part of which he disclosed the weak points in the principles of astrology.
Another of his astronomical works, prepared for Hasdai ben Isaac ibn Shaprut, the Jewish statesman of Cordova, consisted of three parts: (1) the nature of the spheres; (2) astronomical calculations; (3) the courses of the stars. The Arabian author Ibn Baitar, in his book on simple medicaments, quotes the following interesting remark on the rose, made by Ibn Tamim in one of his medicinal works: "There are yellow roses, and in Iraq, as I am informed, also black ones. The finest rose is the Persian, which is said never to open."