That Time is it

Greenwich Mean Time (GMT) - and why is it important?

The Greenwich Mean Time is the annual mean (or "average") time at which the Sun traverses the Prime Meridian at the Royal Observatory in Greenwich every single passing day. Mean Time is the time at which the Sun passes through the Prime Meridian at the Royal Observatory in Greenwich. The GMT is Greenwich Mean Time, the Greenwich time. It'?s 10 before Bristol Mean Time and 13 before Cardiff Mean Time.

Basically, the mean time is the time rather than the solare (astronomical) time. Sun time changes throughout the year as the time between the sun exceeding a fixed line of the sun meridians changes. However, each of the days counted by a watch has the same length as the mean length of a sunny one.

It is a way to standardize and regularize time so that we all know exactly what time it is for our (or the) site. GMT was the cosmopolitan norm of the civilian era from 1884 to 1972. What is the origin of Greenwich Mean Time? Only with the invention of the invention of the timepiece in the 1650' it was possible (or useful) to determine the ratio between mean (clock) time and sun time.

He was soon named the first Astronomer Royal and relocated to the new Royal Observatory in Greenwich. He had the best timepieces fitted and adjusted to Greenwich Mean Time, or the mean time at which the sun passed the Greenwich merchidian.

However, at first Greenwich Mean Time was only really important for observers. It was a hundred years later that the fifth astronomer, Royal Nevil Maskelyne, made Greenwich Mean Time available to a broader public. It was a table with "moon distance" dates using Greenwich observation and GMT as the time reference.

Up to the middle of the 19th centuries almost every city kept its own time, which was determined by the sun. The GMT was eventually introduced by the Railway Clearing House throughout Great Britain in December 1847 and thus became the official "Railway Time". In the mid-1850s almost all British government watches were adjusted to Greenwich Mean Time, and in 1880 it eventually became the statutory British reference time.

One was that the US had already selected Greenwich as the foundation for its own domestic time zoning system. For GMT's sake, the Prime Meridian in Greenwich became the center of universal time and the foundation of our GMT's worldwide system of time domains. Today you can see it at the Royal Observatory doors and the watch shown at the top of this page is known as the Schäfertoruhr.

This was the first watch to show Greenwich Mean Time directly to the world. Until 1893, the Shepherd watch was at the core of the British time system. His time was sent by wire to London, Edinburgh, Glasgow, Dublin, Belfast and many other city. Until 1866, time stamps were sent from the watch via the new trans-atlantic U-boat cables to Harvard University in Cambridge, Massachusetts.

Regarding the allocation of the exact time in every day use, it is one of the most important watches that have ever been manufactured. Greenwich Mean Time is home to the historical Royal Observatory. Royal Observatory is open every day from 22-17.