Ḥassān ibn Ḥassān
ḤASSĀN IBN ḤASSĀN
ḤASSĀN IBN ḤASSĀN (second half of tenth century), Spanish astronomer, who was called by some Ḥassān ibn Mar Ḥassān and by others Ali ibn Mar Ḥassān It seems that Ḥassān was not his father's personal name but his family name. Ḥassān was a dayyan in Cordoba. That he lived in the tenth century can be inferred from the date 972 c.e., which he used in his calculations. He was an astronomer who followed the system of al-Battānī, writing three works which were in the possession of Jewish astronomers in *Spain and in Eastern countries during the Middle Ages but were later lost.
Ashtor, Korot, 1 (19662), 197, 297.