SOMETIMES he is referred as Albategni or Albatenius Arabic name: Al-Battani, Abu ‘Abdullah Muhammad Ibn Jabir Ibn Sinan Al-Harrani as-Sabi. An astronomer and mathematician, born in Harran (now in Turkey) around 853 CE. He died in 929 at Qasr Al-Jiss, near Samarra in Iraq. Some of his achievements: u The determination of the solar year as being 365 days, 5 hours, 46 minutes and 24 seconds. u The production of a number of trigonometrical relationships. He also used al-Marwazi's idea of tangents to develop equations for calculating tangents and cotangents, compiling tables of them. u His most important work is his Zij, or set of astronomical tables, known as Al-Zij Al-Sabi with 57 chapters, which by way of Latin translation as De Motu Stellarum by Plato of Tivoli in 1116 (printed 1537 by Melanchthon, annotated by Regiomontanus), had great influence on European astronomy. Copernicus mentioned his indebtedness to Al-Battani and quoted him in the De Revolutionibus (1543).
