acoreus aglaonike al-andalus almagest anaximander andronicus of cyrrhus antikythera mechanism apollonius of perga aratus aristarchus of samos aristillus aristotle armillary sphere astrolabe astronomy in medieval islam attalus of rhodes autolycus of pitane averroes avicenna babylonian astronomy beatrice portinari bion of abdera book of optics callippic cycle callippus celestial sphere charles v of france cicero circle of latitude cleomedes cleostratus conon of samos cosmos counter-earth dante alighieri de revolutionibus orbium coelestium deferent and epicycle dioptra divine comedy dream of scipio early middle ages egyptian astronomy empyrean equant equatorial ring eratosthenes euctemon eudoxus eudoxus of cnidus firmament geminus geocentric model georg von peuerbach gnomon god greek astronomy heliocentrism heraclides ponticus hicetas hipparchic cycle hipparchus hippocrates of chios hypsicles ibn bajjah indian astronomy inertia jean buridan johannes kepler john philoponus jupiter mars menelaus of alexandria meton of athens metonic cycle moon mural instrument musica universalis narratio prima newton nicolaus copernicus nicolaus reimers nicole oresme octaeteris oenopides paul wittich philip of opus philolaus pierre duhem plato posidonius primum mobile psalms ptolemy pytheas saturn science in medieval western europe scipio africanus seleucus of seleucia solid solstice sosigenes of alexandria sosigenes the peripatetic spherical earth strabo sublunary sphere sun tambourine thales theodosius of bithynia theon of alexandria theon of smyrna thomas aquinas timocharis tycho brahe unmoved mover venus zodiac