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
Gardens of the Sun Brazil attempted to return most of the planet to a "natural" state, to the extent that most of Earth's population inhabits a few megacities. The Outers, by contrast, survive by terraforming the moons of Jupiter and the other outer planets and practicing genetic engineering, which caused ideological tension with Greater Brazil, ultimately flaring into a full-scale conflict called the "Quiet War". By the time of "Gardens of the Sun", the war is over. The surviving Outers have been forced to Uranus, Neptune and Pluto as the superpowers of Earth raid the moons of Jupiter and Saturn for Outer knowledge. However,