Theon of Alexandria observes the eclipses of 364
In Alexandria the mathematician and astronomer Theon observed a solar and a lunar eclipse and reported them in his commentary on Ptolemy’s Almagest — they firmly date his activity. His edition of Euclid’s Elements remained the form in which the Elements were read for more than fourteen centuries.
- Date
- between June and November 364exact date unknown: an interval is given
- Place
- Alexandriatoday: Alexandria, Egypt · Middle East and Egypt
- Participants
- Theon of Alexandria
- Threads
- Middle East and Egypt (1st–5th c.)
- Also known as
- Eclipse of Theon; Theon's eclipse; Затмение Теона
Theon, who lived about 335–405, taught mathematics and astronomy in Alexandria; the Byzantine Suda calls him “a man of the Mouseion”, which probably refers to a prestigious school named after the old Museum rather than to the Hellenistic institution itself. He recorded the solar eclipse of 16 June 364 and a lunar eclipse in late November of the same year (dated 25 or 26 November in different reference works), both seen at Alexandria. His report of the solar eclipse has since been used by astronomers to study the secular acceleration of the Moon and the long-term changes in the rate of the Earth’s rotation.
Theon’s commentaries preserve material from lost works such as those of Pappus and explain how Greek astronomers calculated in the sexagesimal system; a lost treatise on the astrolabe attributed to him may have been the first work on the instrument. His edition of Euclid smoothed and amplified the text for students and was the only version known until François Peyrard found an older manuscript in the Vatican Library in 1808. His daughter Hypatia helped him with the commentary on the Almagest and succeeded him at the head of his school.
Connections
Related events
- Ptolemy’s Almagestc. 150 · Middle East and EgyptTheon wrote a commentary on all thirteen books of the Almagest
- Diophantus’ Arithmeticac. 250 · Middle East and EgyptTheon quotes Diophantus — one of the few fixed points for dating the Arithmetica
Same place
- Hero of Alexandria’s aeolipilebetween 50 and 100 · Middle East and Egypt
- Ptolemy’s Geographyc. 150 · Middle East and Egypt
- Destruction of the Serapeum of Alexandriabetween 391 and 392 · Middle East and Egypt
- Battle of the Nile1–3 August 1798 · Middle East and Egypt
Adjacent events in the thread
- Julian’s Persian expedition and the Peace of 3635 March 363 – July 363 · Middle East and Egypt
Meanwhile in the world
Other regions, within a year of this event
Eastern Europe
- Reign of Ermanaric, king of the Greuthungic. 350 – between 370 and 376
- Chernyakhov culturebetween 200 and 250 – between 400 and 430
- Kyiv culturec. 200 – between 400 and 430
Balkans and Anatolia
- Crete earthquake and tsunami of 36521 July 365
- Wulfila’s Gothic Biblebetween 348 and 383
Africa
- Donatist schismbetween 311 and 312 – 411
Central and Northern Asia
- Hunnic kings of Bactria: the Kidaritesbetween 360 and 370 – 467
- The Kushano-Sasanian kingdom in Bactriabetween 230 and 262 – between 350 and 370
South Asia
- Campaigns of Samudragupta and the Allahabad pillar prashastibetween 330 and 353 – between 370 and 376
- The Buddha’s tooth relic is brought to Sri Lankabetween 309 and 371
East Asia
- Kofun period: the age of keyhole tombsbetween 250 and 300 – 538
Southeast Asia and Oceania
- Gold pendant copying a coin of Antoninus Pius at Óc Eobetween 152 and 600
- Óc Eo, the port of Funanbetween 1 and 100 – between 601 and 700
- The yupa inscriptions of King Mulavarman at Kutaibetween 350 and 450
North America
- Late Basketmaker II erac. 50 – c. 500
- Hopewell traditionbetween 200 and 100 BC – c. 500
Latin America
- Teotihuacan at its height: the largest city of the Americasc. 250 – c. 550
- Nazca culture and the Nazca Linesbetween 200 and 100 BC – between 500 and 800
The same period
Sources
- Wikipedia (English): Theon of Alexandria
- Wikipedia (Russian): Теон Александрийский
- O’Connor J. J., Robertson E. F. Theon of Alexandria — MacTutor History of Mathematics
- Jones A. Theon of Alexandria’s Observation of the Solar Eclipse of A.D. 364 June 16 // Journal for the History of Astronomy. — 2012. — Vol. 43, no. 1. — P. 117–118.
- Toomer G. J. Theon of Alexandria // Dictionary of Scientific Biography. Vol. 13. — New York: Scribner, 1976.