Arab astronomer. Al-Farghani wrote Kitab fi al-Harakat al-Samawiya wa Jawami Ilm al-Nujum, (Element of Astronomy), the book on celestial motion and thorough science of the stars, which was translated into Latin in the 12th century and exerted great influence upon European astronomy before Regiomontanus. Al-Farghani determined the diameter of the earth to be 6,500 miles, and found the greatest distances and also the diameters of the planets. His work was printed at Amsterdam in 1669 with notes. Al-Farghani whose full name was Abu'l-Abbas Ahmad Ibn Muhammad Ibn Kathir al-Farghani was born in Farghana, Tansoxiana.