Al-Farghani (äl-färgä´nē) or Alfraganus (ălfrəgā´nəs), d. after 861, Arab astronomer. Al-Farghani was born in Farghana, Transoxania (present-day Fergana, Uzbekistan), and died in Egypt. His most important work, written between 833 and 857, is Elements, a thorough, readable, nonmathematical summary of Ptolemaic astronomy. The book, which circulated in several Latin editions, was widely studied in Europe from the 12th to the 17th cent. Two treatises on astrolabes by Al-Farghani also survive.