Monday, September 21, 2015
The Ghana MTC is at the Center of the Earth
Lines of latitude and longitude form the grid system used on globes, maps and charts. Latitude is a measure of how far north or south somewhere is from the Equator; longitude is a measure of how far east or west it is from the Prime Meridian. Whilst lines (or parallels) of latitude all run parallel to the Equator, lines (or meridians) of longitude all converge at the Earth’s North and South Poles. The north–south line passing through any particular point on the Earth’s surface is known as the “local meridian”.
Although the Equator is the obvious zero point from which to measure latitude, there is no equivalent point from which to measure longitude. In 1884, an international conference decided that the Greenwich Meridian, as defined by the Airy Transit Circle at the Royal Observatory, Greenwich, should be adopted as the Prime or Zero Meridian for the World. (Nice tidbit, eh?)