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 Protestants were killed in the streets by Catholic mobs. At the end of the century, Henry IV was able to return to Paris as King, and permitted Protestants to open churches outside the city. Urban innovation in Paris during the 16th century included the first street lighting, by candles.The first theater opened in Paris in 1548, and the first ballet performance took place at the French court in 1581. At the beginning of the 16th century Paris was officially the capital of France, but the King, Louis XI, had little trust in the Parisians, and resided in the chateaux of