Theon of Alexandria

Theon's commentary on the canons manuales (astronomical tables) of Klaudios Ptolemaios in the manuscript Rome, Biblioteca Apostolica Vaticana , Vaticanus graecus 175, fol. 52v

Theon of Alexandria (* probably around 330/335; † probably around 400) was a late antique astronomer and mathematician.

Theon's lifetime is deduced from chronological notes in his surviving works. According to him, he observed the total solar eclipse on June 16, 364 in Alexandria . He treated a constellation of the year 377 as imminent. His daughter, the mathematician, astronomer and philosopher Hypatia , was born around 355. He does not seem to have lived through the public appearance of Hypatia in the 5th century and her violent death in 415/416; therefore he died around the turn of the century.

Theon worked in Alexandria as a teacher of mathematics and astronomy. In his lessons he dealt with the basic works of Euclid and Klaudios Ptolemaios . According to the Suda , a Byzantine encyclopedia, he belonged to the Museion . He is the last scholar to be told this. Whether the Museion actually still existed at the time is doubtful in research.

Theon's most important work was the editorial editing of Euclid's Elements around 364 ; all Euclid translations known up to the 19th century were based on his adaptation. His eleven-volume commentaries on Ptolemy's Almagest are also well known .

The moon crater Theon Junior is named after the ancient astronomer.

literature

• Alain Bernard: The Alexandrian school. Theon of Alexandria and Hypatia. In: Lloyd P. Gerson (Ed.): The Cambridge History of Philosophy in Late Antiquity. Volume 1, Cambridge University Press, Cambridge 2010, ISBN 978-0-521-76440-7 , pp. 417-436, here: 424-429
• Jacqueline Feke: Théon d'Alexandrie. In: Richard Goulet (ed.): Dictionnaire des philosophes antiques. Volume 6, CNRS Éditions, Paris 2016, ISBN 978-2-271-08989-2 , pp. 1008-1016
• Menso Folkerts : Theon of Alexandreia. In: The New Pauly (DNP). Volume 12/1, Metzler, Stuttgart 2002, ISBN 3-476-01482-7 , Sp. 376-378.
• Konrat Ziegler : Theon of Alexandreia. In: Paulys Realencyclopadie der classischen Antiquity Science (RE). Volume VA, 2, Stuttgart 1934, Sp. 2075-2080.

Web links

• John J. O'Connor, Edmund F. Robertson :  Theon of Alexandria. In: MacTutor History of Mathematics archive .
• NASA: Partial solar eclipse of June 16, 364 (observed by Theon of Alexandria)