Abū ʿAbd Allāh Muḥammad ibn Jābir ibn Sinān al-Raqqī al-Ḥarrānī al-Ṣābiʾ al-Battānī (Latinized as Albategnius, Albategni or Albatenius) (c. 858, Harran – 929, Qasr al-Jiss, near Samarra) was a Muslim astronomer, astrologer, and mathematician. He introduced a number of trigonometric relations, and his Kitāb az-Zīj was frequently quoted by many medieval astronomers, including Copernicus.