an Arabic prince of Batan in Mesopotamia, was a celebrated astronomer, about the year of Christ 880, as appears by his observations. He is also called Muhammad ben Geber Albarani, Mahomet the son of Geber, and Mahomed Arbelensis. He made astronomical observations at Antioch, and at Rasch or Aracta, a town of Chaldea, which some authors call a town of Syria or of Mesopotamia. He is highly spoken of by Dr Halley, as an admirable accountant, in admirandis observationibus exercitissimus.

Finding that the tables of Ptolemy were imperfect, he computed new ones, which were long used as the best among the Arabs; these were adapted to the meridian of Aracta or Rasch. Albategni composed in Arabic a work under the title of The Science of the Stars, comprising all parts of astronomy, according to his own observations and those of Ptolemy. This work, translated into Latin by Plato of Tibur, was published at Nuremberg in 1537, with some additions and demonstrations of Regiomontanus; and the same was reprinted at Bologna in 1645, with this author's notes. Dr Halley detected many faults in these editions.—Phil. Trans. for 1693, No. 104.

In this work Albategni gives the motion of the sun's apogee since Ptolemy's time, as well as the motion of the stars, which he makes one degree in 70 years. He made the longitude of the first star of Aries to be 18° 2', and the obliquity of the ecliptic 23° 35'. And upon Albategni's observations were founded the Alphonsine tables of the moon's motions; as is observed by Nic. Muler, in the Tab. Frigida, p. 248.