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
Introduction to the mathematics of general relativity the gravitational field outside a spherical mass, on the assumption that the electric charge of the mass, the angular momentum of the mass, and the universal cosmological constant are all zero. The solution is a useful approximation for describing slowly rotating astronomical objects such as many stars and planets, including Earth and the Sun. The solution is named after Karl Schwarzschild, who first published the solution in 1916. According to Birkhoff's theorem, the Schwarzschild metric is the most general spherically symmetric, vacuum solution of the Einstein field equations. A Schwarzschild black hole or static black hole is a black hole