What is Claudius Ptolemy best known for?

Claudius Ptolemy is best known for being a 2nd-century Alexandrian astronomer who created a model of the universe with Earth as its centre. Ptolemy's Almagest book became the standard work on astronomy until the 17th century.

What is Claudius Ptolemy's theory?

Claudius Ptolemy's theory of the universe is that Earth is at the centre while the other planets and the Sun move around it. These heavenly bodies move in circles while following another larger orbit that circles the Earth.

Was Claudius Ptolemy's world map accurate?

Claudius Ptolemy's world map was relatively accurate for the Mediterranean region, but because nobody had been there, other parts of the world were in error, notably having the Indian Ocean as an inland sea bordered by a southern continent.

Claudius Ptolemy

Definition

Claudius Ptolemy (c. 100 to c. 170 CE) was an Alexandrian mathematician, astronomer, and geographer. His works survived antiquity and the Middle Ages intact, and his theories, particularly on a geocentric model of the universe with planets following orbits within orbits, were hugely influential until they were replaced by the heliocentric model of the universe proposed by Copernicus and Galileo.

More about: Claudius Ptolemy

Timeline

c. 100 CE - c. 170 CE
Life of the Alexandrian astronomer and geographer Claudius Ptolemy.
c. 150 CE - 1150 CE
Claudius Ptolemy publishes Almagest, which becomes the primary book on astronomy.

Timeline Search

Search through the entire ancient history timeline. Specify between which dates you want to search, and what keywords you are looking for.