O. Gingerich's scientific contributions

Citations

... 428-347 BC) that the Earth was the centre of the universe and that all the other astronomical bodies revolved in circular orbits around the Earth – as observed by the naked eye. Aristotle (384-322 BC) (see Stocks, 1922), Plato's student, argued for a crystal sphere carrying each such astronomical body where the gaps between spheres were filled with solid aether, the spheres themselves being concentric. Less predictable movements of nearby planets required an embedded sphere to account for their more erratic observed behaviour. ...