Europe in the Roman age (1st–5th c.)Science and technology

Ptolemy’s Almagest

In Alexandria Claudius Ptolemy completed the Mathematical Syntaxis, later known as the Almagest — a synthesis of Greek astronomy whose geocentric model of the universe remained authoritative for some 1,400 years.

Date: c. 150year known, approximate
Place: Alexandriatoday: Alexandria, Egypt · Middle East and Egypt
Participants: Ptolemy
Threads: Europe in the Roman age (1st–5th c.)
Also known as: Mathematike Syntaxis; Syntaxis mathematica; Математическое собрание

In thirteen books Ptolemy set out a mathematical theory of the motions of the Sun, Moon and planets around a stationary Earth, using eccentric circles, epicycles and the equant, and added a catalogue of 1,022 stars in 48 constellations. The treatise was written in Greek around 150; its usual name comes from the Arabic al-majisṭī, a corruption of the Greek for “the greatest”.

Translated into Arabic in the 9th century and from Arabic into Latin by Gerard of Cremona in 1175, the Almagest dominated astronomy in the Islamic world and in Europe until Copernicus proposed a heliocentric system in 1543.

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