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The International Date Line, Prime Meridian and Time Zones

Location: 
World
Date: 
February, 2024
Entry By: 
Joe F.

In the 1800s world trade and shipping was at such a pinnacle that timings needed to be agreed upon. The British Royal Observatory in Greenwich, London was accepted as the Prime Meridian or 0 degrees Longitude. The British navy, merchant ships, expeditions and exploration had the navigational skills to enforce their beliefs and power.

 
The Prime Meridian is a North-South imaginary line running from the North Pole to the South Pole. Prior to 1884, Paris, France also claimed to be at 0 degrees Longitude, this meeting in 1884, held In Washington, USA agreed by the 26 nations present that Greenwich, London, UK would be 0 degrees Longitude. This is the astronomical clock, where East meets West.

 

On the Transit Circle, the Observatory shows, that the earth is a sphere of 360 degrees. Going west from Greenwich and travelling to the halfway point of 180 degrees, you arrive at the International Date Line, another imaginary line dividing the East and West hemispheres, in the middle of the Pacific Ocean. This is the demarcation zone separating two calendar dates, if continuing east you substrate a day while going west you add on a day. This is not by any means a straight line, due to some of the island countries that’s on this line, to prevent a time zone, this line is curved around them, taking up its trajectory having cleared the island. The huge landmass between Asia and North America in the Bering Strait, Cape Dezhnev, Russia is always a day ahead of Cape Prince of Wales, in Alaska, even though there’s only 80 kilometres between them.

 

Greenwich Mean Time, is standard time worldwide, in 1992 UTC started to be used, Coordinated Universal Time. In 1876 was the first time zones came into being, Sir Sanford Fleming was a Scottish engineer who helped design the Canadian railway system, his desire was to make the railroad more efficient and avoid complications that would be inevitable resulting from different train stations that were setting the time schedules according to their local astronomical conditions. He proposed a system, a circle of 360 degrees should be divided into 24 time zones. Dividing 360 degrees by 24 hours gives 15, so every 15 degrees one travels that gives you an hour difference, plus or minus depending if one goes east or west. To begin with all clocks would be set at midday depending on the readings of the Sun. The system was adapted and now we have 24-time-zones. Yes there are countries that do not use daytime saving but internationally that’s allowed for. 

 

Sundials, water clocks, and sticks stuck in the ground to measure the shadows of the Sun indicating the length or shortness of the days. In hindsight this worked perfectly well for the areas people lived in. Travelling long distances was not usual and so it wasn’t noticed. Sailors and merchants going overseas realized a drop in temperatures, or the decline in growth and changes in the seasons were different to what they had left at home. Scientists, astronomers, religious scholars, architects, artists and others were becoming aware of a broader universe. Expanding into a different world, times were changing and so were the needs for a more modern understanding of the world.