History of the center of the Universe Sun at the center of our Solar System. The word comes from the Greek ( "helios" "sun" and "kentron" "center"). The notion that the Earth revolves around the Sun had been proposed as early as the 3rd century BCE by Aristarchus of Samos, but had received no support from most other ancient astronomers. Nicolaus Copernicus' major theory of a heliocentric model was published in "De revolutionibus orbium coelestium" ("On the Revolutions of the Celestial Spheres"), in 1543, the year of his death, though he had formulated the theory several decades earlier. Copernicus' ideas were not immediately accepted, but they did
The Continent Makers and Other Tales of the Viagens mid-21st-century to the mid-twenty-second. Individual stories are set on spaceships traveling between planets and individual planets such as Earth, Krishna, Ganesha and Osiris (it being assumed that Terrans will have carried their penchant for naming planets after gods to other star systems). Features of the postulated future include an Earth governed by a World Federation in which Brazil has become the paramount great power, with Terran space travel monopolized by a Brazilian-dominated agency called the "Viagens Interplanetarias" ("Interplanetary Tours" in Portuguese). Interstellar travel is limited to sub-light speeds, as the author eschews such common science fiction gimmicks as hyperdrives. The