Ptolemy's compendium, later known as the Almagest, dominated Western astronomy for 15 centuries. It was also wrong, and it took the fall of an empire to fix it. A basic understanding of the solar ...

In Ptolemy’s great 13 volume work, The Syntaxis, (otherwise known as The Almagest), Ptolemy made observations about the planets that are surprising. Compared with modern astronomical tables ...

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 ...