Greenwich: History, Meridians and the Time

Dear friends, for a long time now, we have been sharing with you our little space filled with stories on the Training Centre Raya London website. We have talked about many things. The time has come to look at a town, now part of London, that plays a major role in military and civilian shipping, not only of the British but of the world as well.

This settlement was marked on a map for the first time in 918 AD under the name Gronwick. It was also mentioned in the Anglo-Saxon Chronicles of 1013, already with a changed name—Grenawick. The name can be translated as “green market town,” and indicates the function of the place in the Middle Ages. At that time, settlements arose naturally around places of trade, growing into cities. It is no coincidence that it was also a place of trade—close to a river port that was a source of overseas goods and a place to send local products on their way to distant lands.

Greenwich is closely connected with British maritime history. Many remarkable buildings can be seen here. The Royal Naval College, which operated as such until 1998 and had a rich past, the National Museum of Naval History, the Queen’s House, which operates today as an art gallery, and the Royal Observatory, associated with astronomical time and navigation around the world, of course.

The Royal Observatory, erected on a hill in the picturesque Greenwich Park, was a defining point of the zero (initial) meridian, setting the geographical longitude that is so important for the coordination of vessels in oceans and seas. All other meridians are measured according to their distance from the zero meridian, passing through Greenwich. Today, the World Geodetic System WSG84 has defined a new prime meridian line, running 102.5 meters east of the previous one.

Greenwich is also the reference point for determining astronomical time on Earth. Greenwich Mean Time (GMT) is a term related to mean solar time and is also related to the determination of the Coordinated Universal Time (UTC). Time zones are also defined relative to the location of Greenwich. They increase eastward from the zero point (from which the calendar date also changes), usually by 1 hour per zone (but sometimes by 30 or 45 minutes), and time is measured as +UTC or -UTC. In other words, by adding or subtracting whole hours or 30, or 45 minutes from the mean time measured in Great Britain, Ireland, Iceland, the Canary Islands, Madeira, the Faeroe Islands, mainland Portugal, and most of West Africa.

Dear friends, there is definitely something worth seeing in Greenwich! Art and history, seafaring, geography, and astronomy—all this is gathered there and gives spirit and radiance to this ancient, but also modern settlement. We would be happy if you could tell us about your journey to Greenwich, which has now become a district of South-East London.

Author: Iveta Radeva