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 ...

Astrophotographers use sophisticated imaging technology to take and edit photographs that bring us the cosmos with startling ...

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.

Now researchers have managed to recover the text written by Ptolemy on a parchment that suffered such a previous recovery attempt. Outermost six rings of the meteoroscope, not to scale.

The Danish astronomer Tycho Brahe became famous as the creator of the geoheliocentric model of the Solar System, which combined elements of Copernicus's heliocentrism and Ptolemy's geocentrism.

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 ...

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.