Lupitus of Barcelona, identified with a Christian archdeacon called Sunifred, was an astronomer in late 10th century Barcelona, then part of the Marca Hispanica between Islamic Al-Andalus and Christian France (in 985 changing from Christian back into Muslim hands by the conquest of Al-Mansur). Lupitus was instrumental in the transfer of Arabic mathematics, including the astrolabe and the Hindu–Arabic numeral system to Christian Europe. Gerbert of Aurillac in a letter of 984 asks Lupitus for a translation of an Arabic astronomical treatise, the Sententiae astrolabii. See also Barcelona's astrolabe References Juan Vernet, The pursuit of learning - Moorish rule in Spain - Al-Andalus: where three worlds met, UNESCO Courier, Dec 1991. Medieval Catalan astronomers Medieval Spanish astronomers 10th-century astronomers 10th-century mathematicians 10th-century Catalan people