Claudius Ptolemy, a Greek-speaking scholar working in Roman Alexandria, gathered the astronomy of his predecessors into a thirteen-book treatise now known by its Arabic-derived name, the Almagest. It presents a model of the cosmos with the Earth at the centre and the planets moving on circles within circles, together with tables for predicting eclipses and planetary positions, and a catalogue of 48 constellations. The work became the standard textbook of astronomy for some 1,400 years in the Islamic world and in Europe. It was only displaced when Copernicus and Kepler proposed that the planets orbit the Sun.
Before and after
- c. 135 CEConstruction of Castel Sant'Angelo
- 142 CEConstruction of Antonine Wall
- 142 CEOrigins of Temple of Antoninus and Faustina
- 150 CEBirth of Nagarjuna
- c. 150sPtolemy writes the Almagest
- 161 CEOrigins of Odeon of Herodes Atticus
- from 165 CE to 180 CEAntonine Plague
- from 166 CE to 180 CEMarcomannic Wars
- 170 CEDeath of Ptolemy
More in Science & technology
- 287 BCEBirth of Archimedes
- c. 270s BCEAristarchus of Samos proposes that the Earth orbits the Sun
- 212 BCEDeath of Archimedes
- c. 131 BCEHipparchus discovers the precession of the equinoxes
- 1 January 45 BCEThe Julian calendar takes effect
- 132 CEZhang Heng builds the first seismoscope
The era
This moment belongs to the Ancient civilizations (3,200 BCE to 500 CE), writing, cities and empires. You can also browse everything in the 2nd century.