It was believed that the celestial region was made of a fundamentally different kind of matter , who thought it was made of Aether ?
For Aristotle , however , the spheres themselves were made entirely of a special fifth element , " Aether " ( Αἰθήρ ) , the bright , untainted upper atmosphere in which the gods dwell , as distinct from the dense lower atmosphere , " Aer " ( Ἀήρ ) .