Equator 84 (World Geodetic System 1984) which is a standard for use in cartography, geodesy, and satellite navigation including GPS, also has an equatorial radius of 6,378.137 kilometres (3,963.191 mi). For both GRS 80 and WGS 84, this results in a length for the Equator of 40,075.0167 km (24,901.4609 mi). The geographical mile is defined as one arc-minute of the Equator, so it has different values depending on which radius is assumed. For example, by WSG-84, the distance is , while by IAU-2000, it is . This is a difference of less than over the total distance (approximately ). The earth
How Many Miles to Babylon? (novel) How Many Miles to Babylon? (novel) How Many Miles to Babylon? is a novel by Irish writer Jennifer Johnston, first published in 1974. The novel explores the relationship of two men, an Anglo-Irish aristocrat, Alexander Moore, and a lower class son of a labourer on his lands, Jerry, as they experience the First World War. The story is the complex tale of a friendship between two boys in Ireland prior to and during World War I. Alec, the son of Anglo-Irish parents grows up lonely and friendless on his parents' estate in Wicklow during the early years of the 20th