De revolutionibus orbium coelestium Earth's axis rigidly to a Sun-centered sphere. The unfortunate consequence was that the terrestrial rotation axis then maintained the same inclination with respect to the Sun as the sphere turned, eliminating the seasons." To explain the seasons, he had to propose a third motion, "an annual contrary conical sweep of the terrestrial axis". It was not until the Great Comet of 1577, which moved as if there were no spheres to crash through, that the idea was challenged. In 1609, Kepler fixed Copernicus' theory by stating that the planets orbit the sun not in circles, but ellipses. Only after Kepler's
Paris in the 16th century Paris in the 16th century During the 16th century, Paris was the largest city in Europe, with a population of about 350,000 in 1550. The 16th century saw the Renaissance arrive in Paris, expressed in the city's architecture, art and cultural life. The Kings of France returned to Paris from the Loire Valley. Paris. In 1534 Francis I became the first French king to make the Louvre his residence. Under King Francis I, the Renaissance style of architecture, imported from Italy, was widely used in churches and public buildings, replacing the gothic style. Paris landmarks built during the 16th century