Claudius Ptolemy was a Greek mathematician, astronomer and geographer who lived in the Egyptian city of Alexandria while under the rule of the Roman Empire. Much of medieval astronomy and ...

Explore the captivating journey of ancient Greek astronomy in which mythological tales and mathematical precision mix together.

Around the second century C.E., the Greek astronomer Claudius Ptolemy listed 48 "official" constellations in his book Almagest. No original copy of Almagest has survived, so we don't know how he ...

In accord with the Greek ideals of symmetry and harmony, geographer and astronomer Claudius Ptolemy declared that a great northern landmass must be balanced by a twin in the Southern Hemisphere.

Ptolemy, the first century Greek astronomer and mathematician, made his observations of the night skies with the naked eye. In 1609, the Italian astronomer Galileo Galilei upended the Earth ...

An Egyptian astronomer called Ptolemy (AD100-168) described one of the earliest ideas for how the Solar System is structured. Ptolemy’s model and many earlier ideas of the Solar System had the ...

Greek astronomer Claudius Ptolemy, who lived in Egypt, built upon Babylonian knowledge in his geocentric model of the universe. This model, which placed the Earth at the center of the universe ...

helped overthrow more than a thousand years of Aristotelian thinking (reinforced by Greek astronomer Claudius Ptolemy) which said that objects only moved if an external force drove that motion.

Ptolemy was not the first classical author to describe Central Europe, and the territory of Bohemia, Moravia and Silesia in particular. The importance of his work is rather concerned with a list of ...