Why does time start in greenwich england




















Before this, almost every town in the world kept its own local time. 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 s and s, there needed to be an international time standard.

Greenwich was chosen as the centre for world time. Find out more about Greenwich Mean Time. Find out more about Airy's Transit Circle. 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 intersection between these two invisble lines is in the middle of the Atlantic Ocean. It's a bit harder to get a selfie standing on this spot! Between and 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 IRM passes This meant the need for an national time standard became imperative. British railway companies started introducing a single standard time across their networks, designed to make their timetables less confusing. It was mostly Greenwich Mean Time that they used. It officially became 'Railway Time'. There were two main reasons for this. The first was that the USA had already chosen Greenwich as the basis for its own national time zone system.

As the reference for GMT, the Prime Meridian at Greenwich therefore became the centre of world time and the basis for the global system of time zones. Therefore this also became the start of the Universal Day. The meridian line is marked by the cross-hairs in the Airy Transit Circle eyepiece.

Find out more about the Airy Transit Circle. The Shepherd gate clock can be seen at the gates to the Royal Observatory. It was the first clock ever to show Greenwich Mean Time directly to the public. It is a 'slave' clock, connected to the Shepherd master clock which was installed at the Royal Observatory in From that time until , the Shepherd master clock was the heart of Britain's time system.

Its time was sent by telegraph wires to London, Edinburgh, Glasgow, Dublin, Belfast and many other cities. By , time signals were also sent from the clock to Harvard University in Cambridge, Massachusetts via the new transatlantic submarine cable. Donate now. Popular on Time Out [image]. Discover the best of the city, first. We already have this email.

Try another? Latest news. Get us in your inbox Sign up to our newsletter for the latest and greatest from your city and beyond. But this problem was not taken into account until the postal service began.

Early posts were delivered by runners and they were supposed to wait for each other at a certain time at an appointed place. But while it was noon at village A, it was still 11 a.

By the next century when the railways were developed, it was altogether a different story. With the railways connecting distant towns and cities, it became imperative for passengers to know when the train would arrive and also what time they would reach their destination. Sometimes travelers missed their connecting train as various towns stuck to local time calculated according to the sun at noon.

For instance, if the distance between New York and Chicago was to be covered in 18 hours and the train left New York at 10 a.

No doubt it reached at 6 a. New York time, but the Chicago local time was something like 10 p. Britain was the first country to accept that a standard time was necessary and decided to adopt a single consistent time across the country to regulate train timings. The original idea was credited to Dr. William Hyde Wollaston , which was taken up and implemented by Abraham Follett Osler However, the United States was a different story.

It is so vast and as we know today, each state is in a different time zone.



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