Medieval people imagined the earth to be at the still centre of a dynamic cosmos. It was enclosed within multiple transparent spheres, nested closely within one another like the layers of an onion (a popular analogy of the time).
Water
A quarter of the sphere of earth was thought to be elevated above the sphere of water.
Air
Its qualities are hot and moist and its humour is blood
Fire
Its qualities are hot and dry and its humour is yellow bile
Moon
The Moon completes its circuit in one year. The diameter of the Moon is 1,896 and the diameter of its orbit is 101,261 miles.
Mercury
Mercury completes its circuit in one year. The thickness of its planetary sphere is 370,122 miles and its diameter is 230 miles.
Venus
Venus completes its circuit in one year. The thickness of its sphere is 3,313,545 miles and its diameter is 2,884 miles.
The Sun
The Sun is the largest planet and is in the fourth sphere. The Sun’s sphere is 375,762 miles thick and its diameter is 35,700 miles.
Mars
Mars completes its circuit in two years. The thickness of its sphere is 218,083,446 miles and its diameter is 7,572 miles.
Jupiter
Jupiter completes its circuit in twenty years. Its sphere is 20,192,626 miles thick and the planet itself has a diameter of 29,641 miles.
Saturn
Saturn is the last of the planets and completes its circuit in thirty years. Its planetary sphere is 20,843,044 miles thick and its diameter is 29,209 miles.
The Sphere of Fixed Stars
The Sphere of Fixed Stars is the last of the planets and completes its circuit in thirty years. Its planetary sphere is 20,843,044 miles thick and its diameter is 29,209 miles.
The Angelic Movers
How did the spheres of the medieval cosmos move? Late medieval scholars thought that each sphere received its intelligence (originating with God) from the sphere above, and also had a soul. The actions of both the intelligence and the soul moved the sphere.
2D Model Further Reading
Medieval people imagined the earth to be at the still centre of a dynamic cosmos. It was enclosed within multiple transparent spheres, nested closely within one another like the layers of an onion (a popular analogy of the time).
Medieval Universe quiz
Medieval people imagined the earth to be at the still centre of a dynamic cosmos. It was enclosed within multiple transparent spheres, nested closely within one another like the layers of an onion (a popular analogy of the time).
A quarter of the sphere of earth was thought to be elevated above the sphere of water.
Its qualities are hot and moist and its humour is blood
Its qualities are hot and dry and its humour is yellow bile
The Moon completes its circuit in one year. The diameter of the Moon is 1,896 and the diameter of its orbit is 101,261 miles.
Mercury completes its circuit in one year. The thickness of its planetary sphere is 370,122 miles and its diameter is 230 miles.
Venus completes its circuit in one year. The thickness of its sphere is 3,313,545 miles and its diameter is 2,884 miles.
The Sun is the largest planet and is in the fourth sphere. The Sun’s sphere is 375,762 miles thick and its diameter is 35,700 miles.
Mars completes its circuit in two years. The thickness of its sphere is 218,083,446 miles and its diameter is 7,572 miles.
Jupiter completes its circuit in twenty years. Its sphere is 20,192,626 miles thick and the planet itself has a diameter of 29,641 miles.
Saturn is the last of the planets and completes its circuit in thirty years. Its planetary sphere is 20,843,044 miles thick and its diameter is 29,209 miles.
Celitelat is the last of the planets and completes its circuit in thirty years. Its planetary sphere is 20,843,044 miles thick and its diameter is 29,209 miles.
Acknowledgements
This website was designed by Dr Sophie Page (UCL). Thanks to Rakhe Mahia Abedin and Kathleen Walker Meikle for their help in developing the concepts.