The standard geocentric model assumed that the planets were arranged out from the center, the earth, according to the period of revolution. On this assumption, the shorter the period, the closer the planet was to the stationary, central Earth.[1] Claudius Ptolemy ensconced the order in his Syntaxis (commonly know as his Almagest) sometime in the […]
This diagram showing the structure of the cosmos comes from Nicephorus Blemmydes’ “Epitome physica.” At the center is the sphere of elemental earth surrounded by a narrow sphere of water. Then a broad sphere of air surrounds them capped by the sphere of fire. Separating the elements from the heaves is the sphere of the […]
This diagram represents the geocentric cosmos, with the earth (γῆ) at the center, surrounded by spheres of the Moon (σελήν), Mercury (ἐρμῆς), Venus (ἀφροδίτη), the sun, Mars (ἄρης), Jupiter (ζεύς), and Saturn (κρόνος).[1] An incomplete ring for the signs of the zodiac encircles the planetary spheres—only the symbol for Aries was added. Finally, the names […]