Before revision: U.S. Vanguard 1 satellite data from 1958 confirms that the southern equatorial bulge is greater than that of the north, which is corroborated by the South Pole's sea level being lower than that of the north .
After revision: U.S. Vanguard 1 satellite data from 1958 indicates that the North Pole's sea level is raised about with the bulge of the Southern Hemisphere being slightly increased .