According to
mediaeval European cosmology, the
Earth lay at the
center of the
universe, while the
stars were points of
light on a tremendous
sphere that surrounded the world, to which all the other
planets and
heavenly bodies, including Earth's
moon, were attatched. The sphere
rotated around the Earth, thus producing the movement of the planets and stars. This sphere was called the
Primovant.
This explanation of the workings of the universe was accepted until Galileo Galilei disputed it in the early 1600s. He was jailed as a heretic by the Catholic Church, of course, since the idea that the Earth lay at the center of the universe was the basis for so much Catholic theology.
The Catholic Church admitted that Galileo was correct in 1992, some two hundred and fifty years after everyone else.