The spheres of Ptolemaeus

Circle, Sphere
In the 6th century church of Santa Maria della Croce in Casarano (Puglia - Italy) the cosmic references are obvious. Above the altar there's a dome. In the apex of this dome there's a cross in a starry sky, surrounded by coloured rings. The whole represents the spheres in the astronomic model of Ptolemaeus, as it was decribed later by Dante: from outside to inside you can see the spheres of the Moon, Mercury, Venus, the Sun, Mars, Jupiter, Saturn, the fixed stars and ultimately the skyblue invisible Primum Mobile with the cross in its centre.