SYMBOLIC AND COSMOLOGICAL ASTRONOMY IN THE ART OF ROME

Between sky and stone: the cosmos hidden in the Eternal City

Rome is a city built under the sky — but it is also, in a quite singular way, a city that has built the sky. The Pantheon is a perfect sphere in concrete: the dome is the celestial vault, the floor is the earth, the oculus is the sun. Whoever enters it enters the universe. Sixteen centuries later, Michelangelo designed for St Peter's a dome that would honour it and surpass it in theological density. In between, Rome filled domes, apses, ceilings and squares with mosaic stars, painted planets and floor zodiacs — translating into built form every cosmological system that passed through it: Ptolemaic cosmology, early Christian cosmology, Renaissance cosmology, Baroque cosmology. This itinerary traces that built sky in six stops, from Hadrian's Pantheon to Scipione Borghese's Borghese Gallery. It begins at the Roman star vault in the Museo Nazionale, passes through the early Christian mosaics of Santa Costanza — where the cosmology of Ptolemy is baptised and transformed into a geography of salvation —, climbs to the Sistine Chapel, where Michelangelo paints the creation of the cosmos as an act of the Platonic Demiurge, and arrives at the dome of St Peter's, completed in 1590, the year in which Giordano Bruno published his treatises on the infinite and centreless universe.