The line diverges from the South Eastern Main Line at North Kent East junction [1] and runs as far as Charlton junction [2] where it connects with the North Kent Line .
The line in Greenwich represents the historic Prime Meridian of the World - Longitude 0º. The cross-hairs in the eyepiece of the Transit Circle precisely defined Longitude 0° for the world.As the Earth’s crust is moving very slightly all the time the exact position of the Prime Meridian is now moving very slightly too, but the original reference for the prime meridian of the world remains the Airy Transit Circle in the Royal Observatory, even if the exact location of the line may move to either side of Airy’s meridian.Where longitude is the distance east or west of the Prime Meridian line, latitude is measured by the distance north or south of the equator.

The line itself divided the eastern and western hemispheres of the Earth - just as the Equator divides the northern and southern hemispheres. Since 1884, the Prime Meridian has served as the reference point for Greenwich Mean Time (GMT). The prime meridian is a geographical reference line that passes through the Royal Observatory, Greenwich, in London, England. Thus the circle was aligned with the local vertical or plumb line, which is deflected slightly from the normal, or line perpendicular, to the reference ellipsoid used to define geodetic latitude and longitude in the This article is about a historical prime meridian. Greenwich was chosen as the centre for world time. The Royal Observatory at Greenwich was agreed as Zero Degrees Longitude for the whole world at a conference in America in 1884. For the general concept and information on modern prime meridians, see Voting took place on 13 October and the resolutions were adopted on 22 October 1884.Malachy Postlethwayt. Vol. It was first established by Sir George Airy in 1851, and by 1884, over two-thirds of all ships and tonnage used it as the reference meridian on their charts and maps. By the end of the conference, Greenwich had won the prize of Longitude 0º by a vote of 22 to 1 against (San Domingo)Between 1984 and 1988 an entirely new set of coordinate systems were adopted based on satellite data and other measurements and required a prime meridian that defined a plane passing through the centre of the Earth.The true prime meridian of the world, as agreed by every nation on the planet in 1984, is the IERS Reference Meridian, which is also known as the International Reference Meridian or IRM.The IRM is the only meridian that may now be described as the prime meridian of the world, as it defines 0Discover more about the famous Prime Meridian line and its historyMembers visit Cutty Sark and Royal Observatory for free, and will receive...The historic Royal Observatory is the home of Greenwich Mean Time (GMT)....This circle and telescope were originally proposed by the seventh Astronomer...What is the Prime Meridian and why is it in Greenwich? Greenwich Meridian Interactive map of the location of UK Meridian markers. If you stand with one foot on one side and the other on the left, you are perfectly in the middle of east and west, according to the prime meridian line. Greenwich Parent places: England; Old Maps Online. It's a bit harder to get a selfie standing on this spot!The Greenwich Meridian was chosen as the Prime Meridian of the World in 1884.

The line itself divided the eastern and western hemispheres of the Earth - just as the Equator divides the northern and southern hemispheres. The IRM passes 102.5 metres to the east of the historic Prime Meridian of the World at the latitude of the Airy Transit Circle here. Timeline Attributes. The Greenwich Meridian (accuracy 98% guaranteed, but not 100%) 1 "A New and Correct Map of the Coast of Africa". Greenwich meridian, imaginary line used to indicate 0° longitude that passes through Greenwich, a borough of London, and terminates at the North and South poles. The plane of the prime meridian is parallel to the local gravity vector at the Before the establishment of a common meridian, most maritime countries established their own prime meridian, usually passing through the country in question. An international conference held in Washington, D.C., in 1884 designated “the meridian passing through the centre of the transit instrument at the Observatory of Greenwich as the initial meridian for longitude.” The Royal Observatory lies at Longitude 0° by the original definition of Airy's Transit Circle, and at Latitude is 51° 28' 38'' N.The intersection between these two invisble lines is in the middle of the Atlantic Ocean.
& F. Rivington. longitude by international agreement. Every place on Earth was measured in terms of its distance east or west from this line. Drag sliders to specify date range From: To: Fulltext search: Title: Author: Map scale: to.

The transit circle was built by the 7th Astronomer Royal, Sir George Biddell Airy, in 1850. Old maps of Greenwich Discover the past of Greenwich on historical maps Browse the old maps. (4th edition) London: W. Strahan, J. This conference selected the meridian passing throug… 1000-2010 Mercator. There were no national or international conventions which set how time should be measured, or when the day would begin and end, or what length an hour might be.When the railway and communications networks expanded in the 1850s and 1860s, there needed to be an international time standard.